Cam bearing Reengineering for PD motors

Franko6

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Spoon Miller,

That is impressive work with a Dremel tool to cut bearings. Only one problem. I would not advise removing any of the bearing material from the bottom bearing. The reason is that there is already reduced support for the lower bearing. You've decreased to total support even more.

The cam follower bore cuts substantially into the support of the bottom cam shell. The point of greatest load on the bearing is almost exactly at the point of least support. Why would you want to cut even more from that bearing surface? The wider the bearing surface at the load area, the longer the bearing is going to last.
 

Franko6

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Waiting for the 'after' pics! Be sure to take pics of each cam lobe if you decide to take it out. Also the lifters :)
Henrick,

I feel you waiting in the wings for our cam failures.

We can now have some big mile reports of success. We've been doing this a while now, and some drivers who have done my bearing and cam mods are way down the road, with glowing success in areas that normally are prone to heat related failures.

Henrick, I know you are a strong supporter of VW parts, and also, not tinkering with VW engineering. However, we heard several cam engineers that after looking at PD cams make comments like, "What were they thinking?", or "I've always admired German engineering, but I don't understand this..". We have addressed several engineering problems with the PD to improve the engine's longevity and performance.

We found last week a Scandinavian company that agrees with us. They too, have created a longer valve guide with a larger diameter than the stock guides. So, we are not the only ones who have not only seen, but created solutions for these engineering problems.
 

Franko6

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zanzabar, why did you use the TTY torque or Frank's bolts? They would be horribly over-torqued and probably damaged if you did.
Zanzabar,

We developed the cam kit over time. We did not get all our fixes in at once. At the time we were working with you, Zanzabar, we had not finished our engineering tests for the bolts. We now use non-stretch bolts and use a straight-torque value. The cam cap bolts are torqued in stages (60 in lbs., 120 in. lbs., 144 in lbs.) and the rocker bolts are torqued to 25 ft lbs. (22 ft lbs. for the #1 and #8 bolt).
 

Franko6

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I am in the process of looking at my followers at this very moment. Once the center of a new black follower wears through you must replace it as the metal beneath is soft and picks up on the lobe. Just replace the followers that show metal and add 1.5 ounces of Zddplus to your oil and check it in 35000 km. Also remove any metal from the lobe that may have picked up. I thought it was a gouge at first but it is metal transferred from the scored black follower.
Edit I now see you had addressed this to Frank. He does need to reply to another post here as well.
James & Son,
This is not true about the nitrided lifters. It's also not a good idea to replace lifters without replacing the cam.
The nitride coating is a sacrificial element. Although it is very hard, I will give you something to think about. The Cummins 6.9l engine's lifters are almost exactly the same size as a VW PD engine and the total horse power for the Cummins is at least three times as much. Cummins doesn't use nitrided lifters... Why not? Is this only about engine speed?
The main reason for the nitride is a wear coating. It is intended to wear. The chrome/ moly caps under the nitride are also very hard. But as an additional advantage for breaking the cam in properly, the nitriding is an improvement. We have seen late year model BEW's (which have all the lifters nitrided), with the nitriding completely worn off. the cam followers are smooth and in perfect condition. And you think they should be changed out??
Most people don't know this, but the original cam followers installed into the U.S. BEW were NOT NITRIDED. Even so, several early BEW engines far out-lasted their BRM counterparts. After about 1 year, they started installing all nitrided lifters on all the BEW's. The BRM series had only the EXHAUST cam followers nitrided. The intakes were non-nitrided and apparently the same as an ALH lifter. Most people never noticed this because you don't take apart a perfectly good running engine. By the time the owner does see the lifters, they are so damaged, they all look much the same. Look at the edges of the lifters.. that will tell the story.
Our contention is that the cam followers were wearing out because: 1) the cam followers are under-oiled. That is the reason for our cam bearing modification and 2) because the cam profile is a solid lifter profile design that slaps the lifters open. We have designed our profile to overcome that issue.
We haven't tried it yet, but we are going to experiment with non-nitrided lifters in an engine that we are building as the wife's new ride. When we have enough documentation to show the cam wear issue is abated in cam and oiling design, we will offer our commentary about the use of non-nitrided lifters in a PD engine.
 
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zanzabar

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Is it possible that the torque on the caps and rocker shafts is partly to blame here and I can alleviate this somewhat by re-torquing properly to relieve the cocking on the #1 cam cap?
Hi Frank, thanks for the response but this is the question I'm really looking for an answer to at the moment. I realize that tty bolts are not really conducive to re-torquing, but could I perhaps replace one or two of the bolts and make the situation better?
 

Franko6

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Zanzabar,

If you like, I'll send you a set of bolts to replace the tty bolts. No problem..

These are the torque specs:

Cam Cap Bolts Three Stage Torque:
1) First Stage, 60 in. lbs. Use a plastic mallet and strike cam caps. Check free movement of camshaft.
2) Second Stage, repeat using 120 in. lbs.
3) Third Stage, finish torque to 144 in. lbs.

Rocker Shaft Bolts Torque Spec:

1) Mark each rocker shaft and return the shaft to it's original location
2) Pull rocker bolts down until seated
3) Torque #1 and #8 bolts (end bolts) to 22 ft. lbs.
4) Torque remaining pairs of 6 bolts to 25 ft. lbs.

Finish installation by checking the rocker ball screw clearance.
1) Rotate cam until each rocker in turn, is fully depressed.
2) Loosen ball screw lock nuts and turn ball screw against spring pressure until screw 'bottoms out' injector.
3) Turn the ball screw in the reverse direction 180 degrees (1/2 turn)
4) Tighten ball screw lock nut to 24 ft. lbs.
 
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James & Son

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James & Son,
This is not true about the nitrided lifters. It's also not a good idea to replace lifters without replacing the cam.
The nitride coating is a sacrificial element. Although it is very hard, I will give you something to think about. The Cummins 6.9l engine's lifters are almost exactly the same size as a VW PD engine and the total horse power for the Cummins is at least three times as much. Cummins doesn't use nitrided lifters... Why not? Is this only about engine speed?
The main reason for the nitride is a wear coating. It is intended to wear. The chrome/ moly caps under the nitride are also very hard. But as an additional advantage for breaking the cam in properly, the nitriding is an improvement. We have seen late year model BEW's (which have all the lifters nitrided), with the nitriding completely worn off. the cam followers are smooth and in perfect condition. And you think they should be changed out??
Most people don't know this, but the original cam followers installed into the U.S. BEW were NOT NITRIDED. Even so, several early BEW engines far out-lasted their BRM counterparts. After about 1 year, they started installing all nitrided lifters on all the BEW's. The BRM series had only the EXHAUST cam followers nitrided. The intakes were non-nitrided and apparently the same as an ALH lifter. Most people never noticed this because you don't take apart a perfectly good running engine. By the time the owner does see the lifters, they are so damaged, they all look much the same. Look at the edges of the lifters.. that will tell the story.
Our contention is that the cam followers were wearing out because: 1) the cam followers are under-oiled. That is the reason for our cam bearing modification and 2) because the cam profile is a solid lifter profile design that slaps the lifters open. We have designed our profile to overcome that issue.
We haven't tried it yet, but we are going to experiment with non-nitrided lifters in an engine that we are building as the wife's new ride. When we have enough documentation to show the cam wear issue is abated in cam and oiling design, we will offer our commentary about the use of non-nitrided lifters in a PD engine.
I have a PD 2006 BRM can I use the ALH non-nitide hydraulic lifter in my engine.

I know this is still at start stage but under what circumstances do you theorize that the non-nitride lifter is better than the nitride black lifter.

I am going to have to go on your gut feel. Should they be more compatible with your cam profile than the nitride?
 

James & Son

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ALH Followers in BRM?

James & Son,
This is not true about the nitrided lifters. It's also not a good idea to replace lifters without replacing the cam.
The nitride coating is a sacrificial element. Although it is very hard, I will give you something to think about. The Cummins 6.9l engine's lifters are almost exactly the same size as a VW PD engine and the total horse power for the Cummins is at least three times as much. Cummins doesn't use nitrided lifters... Why not? Is this only about engine speed?
The main reason for the nitride is a wear coating. It is intended to wear. The chrome/ moly caps under the nitride are also very hard. But as an additional advantage for breaking the cam in properly, the nitriding is an improvement. We have seen late year model BEW's (which have all the lifters nitrided), with the nitriding completely worn off. the cam followers are smooth and in perfect condition. And you think they should be changed out??
Most people don't know this, but the original cam followers installed into the U.S. BEW were NOT NITRIDED. Even so, several early BEW engines far out-lasted their BRM counterparts. After about 1 year, they started installing all nitrided lifters on all the BEW's. The BRM series had only the EXHAUST cam followers nitrided. The intakes were non-nitrided and apparently the same as an ALH lifter. Most people never noticed this because you don't take apart a perfectly good running engine. By the time the owner does see the lifters, they are so damaged, they all look much the same. Look at the edges of the lifters.. that will tell the story.
Our contention is that the cam followers were wearing out because: 1) the cam followers are under-oiled. That is the reason for our cam bearing modification and 2) because the cam profile is a solid lifter profile design that slaps the lifters open. We have designed our profile to overcome that issue.
We haven't tried it yet, but we are going to experiment with non-nitrided lifters in an engine that we are building as the wife's new ride. When we have enough documentation to show the cam wear issue is abated in cam and oiling design, we will offer our commentary about the use of non-nitrided lifters in a PD engine.
Let me start again. First of all thank you giving me some insight into the possibility of using a ALH follower. I am not convinced the nitrided lifters with the DLC coating are any better than the regular nitrided followers.
Please look at this link.
http://www.hauzertechnocoating.com/en/coating-application/tribological-applications/

It is great for break in as its characteristics allow an unmated cam lobe to aggressively break in and not damage the cam lobe.

If INA has perfected the combination of nitride substrate with the DLC coating then maybe they will be as good as the original uncoated versions.

My first set of black coated followers did fine until the coating showed the bare steel and then they scored at 44000 km (see my album). These were a cam and dealer warrantee replacement of Sept. 2009. I replaced these with a new set. If as you say the substrate is nitride and has a hardness to an increased depth than the previous set then I think I might be ok as they did breakin but the coating in the center was worn more so than i would have wanted although not showing bare steel yet.

My concern in general is the center of the black follower will wear faster than the rest of the follower creating the CharlieT wave for example. I think INA had not perfected the coating and substrate hardness and depth even as late as 2009. I think I might have got an experimental cam as well as the entire circumference had 9 equal spaced raised grooves which could only be there intentionally by the manufacture.

I think your idea to experiment with an uncoated follower on your cam profile is very prudent. Can I put ALH cam followers in my BRM with an OEM profile or do you grind the cam to suit the ALH follower depth between the valve stem and cam dwell. Let me know.
 

oldpoopie

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Zanzabar,

If you like, I'll send you a set of bolts to replace the tty bolts. No problem..

These are the torque specs:

Cam Cap Bolts Three Stage Torque:
1) First Stage, 60 in. lbs. Use a plastic mallet and strike cam caps. Check free movement of camshaft.
2) Second Stage, repeat using 120 in. lbs.
3) Third Stage, finish torque to 144 in. lbs.

Rocker Shaft Bolts Torque Spec:

1) Mark each rocker shaft and return the shaft to it's original location
2) Pull rocker bolts down until seated
3) Torque #1 and #8 bolts (end bolts) to 22 ft. lbs.
4) Torque remaining pairs of 6 bolts to 25 ft. lbs.

Finish installation by checking the rocker ball screw clearance.
1) Rotate cam until each rocker in turn, is fully depressed.
2) Loosen ball screw lock nuts and turn ball screw against spring pressure until screw 'bottoms out' injector.
3) Turn the ball screw in the reverse direction 180 degrees (1/2 turn)
4) Tighten ball screw lock nut to 24 ft. lbs.

Frank, the OEM bolts have a wider area on them which i assume helps to locate the rockers in the correct spot. When reinstalling the rockers, i generally spin the OEM bolts back in snug, then remove and replace them one at a time with the non stretch ones snugged, THEN torque to spec.

Any thoughts on those wider sections of the OEM bolts?
 

nic_a_bod

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2005.5 Jetta
Surprised it took you this long frank to get the wife a PD. You were showing my Jetta off with all the amenities to her the couple years ago I was down there, I'd thought you'd had a PD shortly after that.
 

Pitzury

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Rocker arm shaft plugs

Here are some pix from the 10k km oil change. It looks about the same as before.Time to button up and run. Comments?
I cannot believe that nobody told him that the little aluminum plug he found loose and he took picture of is one of the 4 plugs in the rocker arm shafts. They often come loose and cause oil pressure loss which lead to cam/lifter wear and turbocharger failures. Black Knight actually lost his turbo later on. In my opinion the wear all around the bearings is from insufficient oil.
 
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Pitzury

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I'm trying to understand why use the rocker arms oil supply for the bearings. Why don't we just connect the cam oil supply hole to the cap bolt hole and then just follow the bolt hole line up to the top shell, right in the middle?All machining would be done on the cap and head journal surface not on the back of the bearing.
Also why not use both bearing slots to supply as much oil as possible to the bearings? It doesn't seem like the lower slot would disrupt oil wedge since oil is under pressure in that area.
 

Pitzury

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I would like to modify the rocker arms shafts to squirt oil onto the cams. Question is how small do the squirt holes need to be to avoid failures like the ones caused by the end plugs loosening. One thing I would like to do is tap the end holes and use screw-in plugs that will not fail.Also, if we start drilling the shafts for cams oil squirters, we will need the oil galleys opened up to clean them from the chips caused.
Until we figure out about these squirt holes we can turn all retaining clips with the opening facing down towards the cams and lifters to direct the oil escaping the rocker arms to where is needed.
 

James & Son

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Maryhill, Ontario, Canada
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2006 Jetta
I would like to modify the rocker arms shafts to squirt oil onto the cams. Question is how small do the squirt holes need to be to avoid failures like the ones caused by the end plugs loosening. One thing I would like to do is tap the end holes and use screw-in plugs that will not fail.Also, if we start drilling the shafts for cams oil squirters, we will need the oil galleys opened up to clean them from the chips caused.
Until we figure out about these squirt holes we can turn all retaining clips with the opening facing down towards the cams and lifters to direct the oil escaping the rocker arms to where is needed.
If you remove the valve cover when your car is at or below room temperature and put cardboard along the pulley and flywheel and back sides( some paper towels pushed in behind as well). Have someone start the car and you should see substantial oil flowing, not splashing but flowing from rockers, cam bearings and follower bores. This will start to happen in 4 to 5 sec. i would say in another 2 to 3 seconds the followers will suddenly be totally encased in a thick coating of oil. Each time the lobe rotates a slug of oil is thrown up on the back cardboard but at no time at idle is the follower visible because it is continually covered with oil. I am not sure what will be happening at high rpms.

I can say this though, extra pissers will make little difference unless your able to direct it consistantly and directly on the cam lobe and follower interface and I am only saying this as I do not have a clue of the availablity of oil at high rpms or its consistancy. But after being involved with the cam wear problems for the last 2 years I tend to believe more than oil flow modifications are necessary. Lastly only the brm has the extra oil volume available to add the extra volume you are talking about. Frank found the BRM has a different sprocket that increases the pump volume by 30% and yet it is the brm that has the most cam wear issues.

Lastly, this is Franks thread about his cam bearing modifications. He wants pros and cons on his bearings which are modified to do exactly what you are talking about. Look up all the posts by Frank( do a search) and modify your bearings the same and then discuss the pros and cons in this thread.
 

Henrick

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James & Son: you you're trying to say we have a dry-start situatiion for about 4-5 seconds each time? That's crazy! No surprise these cams are wearing out that fast...
 

2footbraker

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It starts oiling as soon as the crank starts rotating. When I check cam wear, I unplug the injector harness and blip the starter to rotate the cam a few degrees at a time. Each blip results in the follower tops being covered in oil. This would be roughly a half a crank revolution to oil the follower tops completely.
 

James & Son

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James & Son: you you're trying to say we have a dry-start situatiion for about 4-5 seconds each time? That's crazy! No surprise these cams are wearing out that fast...
Yes exactly like I said but every motor is like this. There is residual oil on the cam followers that cover the first few seconds and this is what every motor relies on until oil flow is established. The oil gallerys have drain back and they must fill and then the oil has to pass through the bearing cleanances. Then run down the bearing mounts but the bearings are not the only source or it would take longer. The motor is tilted back about 5 degrees so not all the oil from the bearing is getting to the follower. It takes the oil from all 3 sources as I stated and then suddenly the follower is engulfed and not visable.

The actual oil require to lubricate is a few drops as the actual oil film thickness is less than .001 inch or .025 mm. and low rpm should not have a oil problem from what I can see. But like I said when I do this test the lobe throws the oil onto the cardboard. At high rpm that oil must be present at the front of the follower for the lobe to pick it up. Stock oiling is not a problem by it self and if your going to increase oiling then you need to know where it is going at high rpm. Since I don't run high rpms all the time and I am still having a wear dot problem I think there is potentially a greater problem and that is cam stability.

I think the cam must be completely stable in the bearings at all times and injection events and spring forces must at all times not affect this stable running position. Otherwise the bearings will no longer be the bearings but the followers will act as the bearings and at injection events the hydraulic followers( valves are locked close do to compression) may be taking a load in excess of 600 or more pounds instead of the bearing.

Thats what I am working on and will find if I am right in the coming months.

2Foot

Join Date: Sep 2005
Location: Saskatchewan, Canada
TDI(s): 06 Jetta, 01 Golf





It starts oiling as soon as the crank starts rotating. When I check cam wear, I unplug the injector harness and blip the starter to rotate the cam a few degrees at a time. Each blip results in the follower tops being covered in oil. This would be roughly a half a crank revolution to oil the follower tops completely.
__________________
Thats exactly what I am trying to say here, oil a low rpms is not the problem the oil pressure to the follower it self may generates enough oil, it self, at low and high rpms as it is the oil reaching the front half of the follower that counts.

I do not want to contunue this discussion on Franks thread as it should mostly pertain to his modifications and suggestions and directed to him.
 
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longo

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The stinging reality is,this cam design leaves a lot to be desired and we'll never be able to overcome the shortcomings of the design nor cope with the loads imposed on the cam by the injectors.

"Driving a VW TDI every day keeps the doctor away."

You are right about the affect of VW ownership and affordable health care!

My 06' Jetta just ate up $1100 to replace a 50 cent bushing on the EGR Cooler that was leaking stinking exhaust fumes into the car. (the new one will wear out just the same) A $300 bill for the alternator pulley that self destructed, flew off and bounced down the road behind me, $900 in 3 DSG fluid changes, a cam shaft that showed worn and scarred lobes to the tune of $1895, not to mention all my black push button radio and window switches that have lost the coating and look like Hell, or the dual control digital readout of the heater temperature that has gone blank.

I don't need a Doctor, I need therapy to cure my VWness.
 
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shuswap

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snipped.... d
I don't need a Doctor, I need therapy to cure my VWness.
Yup, but then I just completed a drive from Vancouver to Edmonton, and back, 1,500 miles, and enjoyed almost every minute of the drive in our 05 Golf.

Watcha gonna do?
 

Franko6

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PD Precision Cam Bore Alignment

Frank, the OEM bolts have a wider area on them which i assume helps to locate the rockers in the correct spot. When reinstalling the rockers, i generally spin the OEM bolts back in snug, then remove and replace them one at a time with the non stretch ones snugged, THEN torque to spec.
Any thoughts on those wider sections of the OEM bolts?
Justin,

The OEM TTY cam and rocker bolts are not as accurate as some might hope. The barrel on the TTY bolts is supposed to center the cam cap on the head, but in many caps, we find the OEM cam bolt is loose in the cam cap's bore as much as .005". Our intention when aligning the cam bearings is to have the cam caps indexing closer to .0005", or ten times as close.

With those close tolerances, we often found the cam was binding in the cam journals. Obviously, additional steps were necessary in order to align the bearings in their caps, even if using the OEM bolts. We use a plastic mallet to strike the cam caps and jar the cam bearings into position and a three-stage torque method. The OEM bolts did little to align the bearings. We haven't used the TTY bolts for the cam or injector shaft for years. We got the engineering worked out, but the methods require some finesse and determination.

More recently, we have worked out two fixes for the cam bore alignment.

First, we have found a roll pin that will accurately index the cam caps to the cylinder head. The pin is pushed into the cylinder head and the cam cap fits on top of it. The repeatability of the hole alignment between the cam cap and the cylinder head is excellent.

Second, we found a cure for the unusual wear pattern in the #1 and #5 cam bearings. It is due to the torque load from the injector rocker shaft.

The PD cylinder heads were machined, initially, with the cam caps separated from the main casting. Then, the cam caps were attached and the cam was align bored. Unfortunately, there are two faults with the method.

1. The indexing is comparatively inaccurate (which we have already addressed...)
2. The injector rocker shaft's torque load was not considered.

The real force holding the cam caps in place is provided by the injector rocker bolts. But the clamping force is unequal for the #1 and the #5 caps, as there is only one offset bolt in the #1 and #5 cam caps. The #2, #3 and #4 rocker bolts are paired and provide equal force for both sides of the cam cap. But even then, there is some amount of squish which was not calculated in the manufacture of the head. The force of the rocker shaft bolts is pushing the cam bearings out-of-round AND out-of-square.

Our correction method is to install the injector rocker shaft in the same manner of a torque plate. Just as boring a performance block,
the purpose is to intentionally apply the the loads that warp the cylinder head and machine the head in that condition. We feel that this correction has cured several issues with cam bearing wear and alignment.

Initial evaluation is excellent. The material removed is precisely where the interference wear is occurring.

We will be using this method of cam align bore correction for each PD cylinder head we see in our shop. As for fixing align bores while the head is still attached to the engine, it is not feasible at this time.
 
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James & Son

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Frank, I always appreciate you updating what you have learned as well as others in the field. I am happy to here you have your new equipement in place now.

But there is definitely an advantage to what Ol' poopie says. Maybe not for you since you say you use a roll pin, but for DIY it definitely is an improvement. Especially in locating the caps in the longitudinal direction.

I also found if you leave the cam bearing shell up .005 on the lower and down .005 opposite side on the upper the combination with the shouldered bolts or doing it as oldpoopie suggests locks the cap in place( not entirely sure if this slight shell offset rotation is necessary but works for me).

You can check the repeatability of this method with a dial gauge. I found once you reach the point you are applying crush it locates the same every time. Of course you need to make sure the cap is very even at this point by slightly bottoming the cap and backing off evenly and then very fine increments until it is seated on the head.

#1469 by Airbeast.
 

oldpoopie

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Justin,

The OEM TTY cam and rocker bolts are not as accurate as some might hope. The barrel on the TTY bolts is supposed to center the cam cap on the head, but in many caps, we find the OEM cam bolt is loose in the cam cap's bore as much as .005". Our intention when aligning the cam bearings is to have the cam caps indexing closer to .0005", or ten times as close.

With those close tolerances, we often found the cam was binding in the cam journals. Obviously, additional steps were necessary in order to align the bearings in their caps, even if using the OEM bolts. We use a plastic mallet to strike the cam caps and jar the cam bearings into position and a three-stage torque method. The OEM bolts did little to align the bearings. We haven't used the TTY bolts for the cam or injector shaft for years. We got the engineering worked out, but the methods require some finesse and determination.

More recently, we have worked out two fixes for the cam bore alignment.

First, we have found a roll pin that will accurately index the cam caps to the cylinder head. The pin is pushed into the cylinder head and the cam cap fits on top of it. The repeatability of the hole alignment between the cam cap and the cylinder head is excellent.

Second, we found a cure for the unusual wear pattern in the #1 and #5 cam bearings. It is due to the torque load from the injector rocker shaft.

The PD cylinder heads were machined, initially, with the cam caps separated from the main casting. Then, the cam caps were attached and the cam was align bored. Unfortunately, there are two faults with the method.

1. The indexing is comparatively inaccurate (which we have already addressed...)
2. The injector rocker shaft's torque load was not considered.

The real force holding the cam caps in place is provided by the injector rocker bolts. But the clamping force is unequal for the #1 and the #5 caps, as there is only one offset bolt in the #1 and #5 cam caps. The #2, #3 and #4 rocker bolts are paired and provide equal force for both sides of the cam cap. But even then, there is some amount of squish which was not calculated in the manufacture of the head. The force of the rocker shaft bolts is pushing the cam bearings out-of-round AND out-of-square.

Our correction method is to install the injector rocker shaft in the same manner of a torque plate. Just as boring a performance block,
the purpose is to intentionally apply the the loads that warp the cylinder head and machine the head in that condition. We feel that this correction has cured several issues with cam bearing wear and alignment.

Initial evaluation is excellent. The material removed is precisely where the interference wear is occurring.

We will be using this method of cam align bore correction for each PD cylinder head we see in our shop. As for fixing align bores while the head is still attached to the engine, it is not feasible at this time.
Frank, that all makes sense, especially align boring with the rockers in place. When I had my new motor built, I had them bore and hone the block with a transmission bell housing bolted to it so any forces on the cylinder would be the same. When machining at extreme precision, you always want to do final machining with the material at as close to the same loads and stresses it will see in use as possible.
 

GoremanX

Veteran Member
Joined
Mar 17, 2013
Location
Vermont
TDI
2001 Audi A4 Avant quattro w/BHW TDI & 01E 6-speed
Any chance the photos in the OP can be restored? Bora Parts links to this thread for "installation instructions" of products they sell, but that OP is frustrating to understand without photos.

edit: thank you
 
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James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
Any chance the photos in the OP can be restored? Bora Parts links to this thread for "installation instructions" of products they sell, but that OP is frustrating to understand without photos.

edit: thank you
Go to photos at the top of this web page and use the index to find Franko6 photo album. You may have to log in again to access the photos. Here I did it for you.
Home » Member » Franko6 » Pump Duese Bearings

 
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GoremanX

Veteran Member
Joined
Mar 17, 2013
Location
Vermont
TDI
2001 Audi A4 Avant quattro w/BHW TDI & 01E 6-speed
Thanks! Useful to know for the future. Luckily, the OP has now been fixed.
 

turbovan+tdi

Top Post Dawg
Joined
Mar 23, 2014
Location
Abbotsford, BC.
TDI
2003 TDI 2.0L ALH, auto, silver wagon, lowered, Colt stage 2 cam, ported head,205 injectors, 1756 turbo, Malone 2.0, 3" exhaust, 18" BBS RC GLI rims. 2004 blue GSW TDI, 5 speed, lowered, GLI BBS wheels painted black, Malone stage 2, Aerotur
We haven't tried it yet, but we are going to experiment with non-nitrided lifters in an engine that we are building as the wife's new ride. When we have enough documentation to show the cam wear issue is abated in cam and oiling design, we will offer our commentary about the use of non-nitrided lifters in a PD engine.
Any update?


Finish installation by checking the rocker ball screw clearance.
1) Rotate cam until each rocker in turn, is fully depressed.
2) Loosen ball screw lock nuts and turn ball screw against spring pressure until screw 'bottoms out' injector.
3) Turn the ball screw in the reverse direction 180 degrees (1/2 turn)
4) Tighten ball screw lock nut to 24 ft. lbs.
You have another way with the cam lobe facing up, which one is better or do they both do the same job?

BTW, check out this video on the black lifters regarding what you said about solid cam profile.

https://www.youtube.com/watch?v=ty-sdftGx40&feature=youtu.be
 

05_new_jetta

Veteran Member
Joined
Aug 28, 2005
Location
Van Wert, OH
TDI
MKV Jetta TDI
While I like the thought behind making something better I have to wonder if it's really necessary. I got 200k out of my replacement stock vw cam, lifters and bearings. 300k total on the car and the oil analysis always cam back better the average tdi according to Blackstone. Not bashing anyone, but with good maintenance the stock stuff lasts just fine above stock power (150whp) .
 

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
05newjetta,

We have had some cams, particularly from the 'Frozen North' that have gotten fantastic wear, well over 400 kilometers, some 500 kilometers.

Then, we have those who weren't able to get 20,000 out of an aftermarket cam. I don't think it's luck. I certainly know there are better and worse cams built out there, but the obvious conclusion, it is not that thousands of PD owners do lousy maintenance, but the POTENTIAL for cam failure is high because the cam design is poor.

So, if you got 200,000 miles from your aftermarket cam and then have to rebuild it again, would it not be better to have a cam/ lifter set that is still going strong? We have a lot of engines with 250,000 miles who have told us, "It looks like it's still breaking in."

Our record-keeper is an ADDITIONAL 450,000 miles. So, there are always exceptions to the case.

There are questions.
1. What oil are you using?
2. What change interval?
3. What is your driving style?
4. Where is most of your driving done? City/ Highway?
5. What distances do you average drive?
6. Is your vehicle automatic or standard?

So, besides the average high temperature, there are several factors which can increase
or decrease life-expectancy of a cam. Our effort is to make a cam that can take abuse better and still survive.

I think we have accomplished that.
 

Kriesel

Veteran Member
Joined
Feb 22, 2009
Location
Afton, MN
TDI
2006 Jetta TDI
There are questions.
1. What oil are you using?
2. What change interval?
3. What is your driving style?
4. Where is most of your driving done? City/ Highway?
5. What distances do you average drive?
6. Is your vehicle automatic or standard?
I'll give my personal input for whatever its worth (currently at 225k miles on original cam). The last oil sample I had done, they said the wear metals are getting lower with more miles, aka, getting better with age:

1. What oil are you using? Mobil 1 Turbo Diesel Truck
2. What change interval? 10k miles
3. What is your driving style? Drive it like it's stolen
4. Where is most of your driving done? City/ Highway? 75% highway
5. What distances do you average drive? Commute has varied throughout the ownership of the car, but anywhere from 1-mile commute to current 20-mile commute
6. Is your vehicle automatic or standard? Manual trans
 
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