Cam bearing Reengineering for PD motors

hid3 said:

x2.

I asked that already two times but got response that 'it just works'. Isn't there any enthusiast who would like to try this out and share the results with us?

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Not sure I'd qualify as an 'enthusiast', but I believe this is what Frank just completed for the BRM head from my car. (Frank?) I believe we also decided to run with a BEW cam to reduce some of the forces and gain longevity. (I'm feeling as though my car has somewhat become a large science experiment, albeit an expensive one.) As the car is just a daily driver, I'm not looking for the highest levels of performance. To that end, the loss of torque is not my highest priority.

With any luck, Troy will have the car back on the road by year's end, and it will start accruing mileage. I'm not sure of the difficulties in removing the bearings for photographs, but I will be happy to do what's necessary to contribute to the body of knowledge that is this board. This assumes that the level of effort does not exceed the knowledge gained.

It might be a while before we get a clear picture of benefit of the mods, and the fact that we changed cams may overstate the impact. So, it will be a while before I can contribute the impacts on my particular car, but know that the results will eventually come out.

-jp

I plan to pull the valve cover this spring and look things over and get some pictures. I don't plan on doing this any sooner as I will do this during the next oil change.

my bearings have 130k on them.. I flipped them when I did the cam because of obvious reasons seen here but I didnt wanna put my car down for a week to get new bearings so I just did that and they still work.. I might roll some new bearings in soon to see how the lowers have worn in 30k. dont really wanna pull my cam again to drill these holes unless I have to.. maybe I'll do it at 200k

Franko6 said:

Using the non-synthetics is what I recommend... better then that, use racing oil for break-in. The initial break-in is, in my opinion, critical.

After installing new cam and lifters, I recommend running the motor 1/2 hr with a 40wt. racing motor oil like Reline, Brad Penn, Joe Gibb or equivalent, varying the engine speed between 2000-2500 rpm. Dump the oil and filter. Refill with racing oil and run for 500 miles. Again at 2500.

If you like, resume the synthetic oils at that time. I prefer 5-40 over 5-30. Motul, Pentosin, Elf, or Lubro Moly are good synthetic choices. I'm not against the Mobil 1. I personally use Lubro Moly in everything up to the 2009's. School's still out on that, so far as I am concerned.

The reason for the track oil is that lubricity. Regardless of API, the 'off-road' oils are only concerned with what makes it work in a performance situation.

You probably make a case for continuing with such hi-grade oil. It is more expensive and not particularly a grade for diesels, which is made to hold a lot of soot in suspension. I still think I'd move to a diesel grade synthetic after break-in.

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I use a 4:1 mix of Liqui Moly Diesel Synthoil 5w40, arguably for diesels, and MoS2 Leichtlauf 10w40. The latter looks like spent oil, very dark brown with slightly iridescent areas and apparent indiscernible specks floating on surface tension. Looks cool, if you ask me.

6500 mile OCI. Thinking of using their boron nitride additive come next OC.

At this rate, I don't think there's anything on God's green Earth that can do my engine in, and it's got roller rockers and no PD. Maybe such treatment would prove prophylactic to TDI PDs.

hid3 said:

x2.

I asked that already two times but got response that 'it just works'. Isn't there any enthusiast who would like to try this out and share the results with us?

Click to expand...

x3...found a lot of magnetic particles on my magnetic drain plug last night. I fear my time is short.

Just replaced the cam in my BHW, and used Franko6 mods...LINK
I should have some ~3000 mile data/pics in early January

We need a Trusted Mechanic List that includes whether Franko6 Moder. I just checked, Franko6 is 1300 miles but right off I40 headed from AZ to NY. Hmm.

ssamalin said:

We need a Trusted Mechanic List that includes whether Franko6 Moder. I just checked, Franko6 is 1300 miles but right off I40 headed from AZ to NY. Hmm.

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That's just a shade over 2 tanks of fuel away....

ssamalin said:

We need a Trusted Mechanic List that includes whether Franko6 Moder. I just checked, Franko6 is 1300 miles but right off I40 headed from AZ to NY. Hmm.

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The upper caps drilling is a DIY. You just order the bolts & bearings directly from Frank, do your own drilling and ask a trusted mechanic to replace the cam & related things at timing belt time...

How can do my own drilling? You mean the galley drilling in the engine? A TM has do that right? That's what I'm asking, which TMs drill the galleys (and install the Franko6 bearings and bolts.)

hid3 said:

The upper caps drilling is a DIY. You just order the bolts & bearings directly from Frank, do your own drilling and ask a trusted mechanic to replace the cam & related things at timing belt time...

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I mean, it's not too difficult to do the drilling yourself and just give the TM Frank's updated parts so he will install them in already drilled head.



Frank, is shipping of your parts (bearings and bolts) possible to Europe?

The drilling of the caps is fairly straight forward, and is done OFF the head. Franko6 explains it well in Post #1.
The drilling of the hole in the head itself above #1 is harder, I decided not to do it simply because I don't feel the wear around #1 bearing is that bad, and the risk of getting aluminum debris in the oil galley was too high (in my opinion). Frank suggests pushing air through an oil galley hole as you drill, good idea.. but his skill set is much higher than mine... so I chickened out !

My current concern is looking at the bearing shell mods. It was only once I got it apart on Sunday that I saw a possible flaw in the current solution.
Somehow everyone keeps saying on here that the factory oiling port is just AFTER the point of max load ? but it is not... it is just BEFORE ?!!? And so the new oiling port is just earlier... but still has to get past the factory slot.
I think this comes from a misunderstanding about cam rotation direction. It is CLOCKWISE when looking from the belt end (front on a BHW).
I think we have missed a detail here ??? or am I nuts ?!

Just set my cruise, take a nap, and walla I'm there.

Rod Bearing said:

That's just a shade over 2 tanks of fuel away....

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I'm waiting for someone who speaks Martian to answer the Charlie post so I can attempt to decide whether the cam was caused by the Martians or the Jupiterainians.

If you mean drilling the galley holes into the engine block, I can't do that. What do mean upper caps? I thought the upper bearing holes were in the Franko6 kit?

hid3 said:

The upper caps drilling is a DIY. You just order the bolts & bearings directly from Frank, do your own drilling and ask a trusted mechanic to replace the cam & related things at timing belt time...

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I really like the bearing mods Frank has done. I don't know if I'd drill the head, probably not.

The spring pressure from the injector is the root of all evil in this design. Hot shutdown leaves the cam under a static load and that load forces oil out from between the cam and bearing. Cold startup is when the wear hits the bearing.

I have an injector out of my test mule Jetta right now to see if anything can be done about changing to a different spring.

What's this about an error Franko6 said? Is his his kit being redesigned due to it? Please keep us civilians informed.

Rod Bearing said:

I really like the bearing mods Frank has done. I don't know if I'd drill the head, probably not.

The spring pressure from the injector is the root of all evil in this design. Hot shutdown leaves the cam under a static load and that load forces oil out from between the cam and bearing. Cold startup is when the wear hits the bearing.

I have an injector out of my test mule Jetta right now to see if anything can be done about changing to a different spring.

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I'll let Frank explain his observations of a mistake here. But the bearing mod he is using on the upper shell is a good one imo.

I won't be for or against any of the ideas here until I am able to get my mind around a way to reduce the injector spring pressure significantly, as I personally believe the lower bearing wear issue is found there and there alone due to static loading at hot shutdown and then a resulting lack of oil between the cam and the bearing at the next cold startup, and on and on...over and over.

I'm all for adding some oil flow to the cam bearings when the engine is running. Franks approach is a good one because if successful, his idea will yield the simplest and least expensive fix.

I just had a cam job at 80k. I'm going to do the Franko6 as soon as I can figure out how to get it. Even if I ride 10 or 20k on my cams I still will want the Franko6 done. I figure once I get the galleys drilled and the reusable bolts, I can do my next cam job at 80k or whatever and will just need Franko6 bearings too. For now I'm glad my car is riding well again. It's a lot better, no hesitation, smoke, limp mode, isn't burning oil, smoother. It was quite a shock reading here about the cam issue, but I'm still in the middle of my car payments and couldn't trade in the car if I wanted to, which I really don't. The 2006 is still the car I want. Ps I got rid of the 505.01 piss and switched to Delvac 5/40 ESP too.

would this cause my lifters to wear a hole

I'm just wondering if this oiling problem would cause a wear problem on the lifters?

Bearing Reversal

ssamalin said:

What's this about an error Franko6 said? Is his his kit being redesigned due to it? Please keep us civilians informed.

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I changed my mind on the value of turning the lower cam bearing around.
At first, I didn't see the advantage, but that was due to my reversed thinking.

I have another thread showing what I'm talking about.

Basically, turning the lower shell around moves the original oiling slot past the point of greatest pressure. The bearing mod I have created oils the top bearing.

As the oil is forced around to the lower bearing, the oil will wedge into the decreasing space between the cam bearing and cam journal. The wedging of the oil increases the oil pressure into the hundreds of pounds. If the lower bearing shell is not turned around, the pressure that has been built going onto the lower shell is lost by being funneled into the OEM oil path of the existing galley hole. That loss of pressure will reduce any advantage of the top bearing modification.

Instead, if the bearing shell is reversed, there is an uninterrupted pressurization of the oil as it crosses into the peak pressure point. In order to carry a film of oil, that pressure rise is paramount. Anything that takes away from that pressure rise is an issue that needs to be dealt with.

Another post shows attempts to hammer in a new tang on the reversed bearing. I see more problems with doing that than advantages. The tang's only purpose is to locate the shell laterally in the saddle. If marked and carefully placed, the crush built into the bearings will maintain the bearing position.

So the Franko6 bearing mod kit is unchanged, but when installing it there are instructions on reversing the lower bearings, which are (in or not in?) the kit? These lower bearings are stock which are simply installed reversed.

Franko6 said:

I changed my mind on the value of turning the lower cam bearing around.
At first, I didn't see the advantage, but that was due to my reversed thinking.

I have another thread showing what I'm talking about.

Basically, turning the lower shell around moves the original oiling slot past the point of greatest pressure. The bearing mod I have created oils the top bearing.

As the oil is forced around to the lower bearing, the oil will wedge into the decreasing space between the cam bearing and cam journal. The wedging of the oil increases the oil pressure into the hundreds of pounds. If the lower bearing shell is not turned around, the pressure that has been built going onto the lower shell is lost by being funneled into the OEM oil path of the existing galley hole. That loss of pressure will reduce any advantage of the top bearing modification.

Instead, if the bearing shell is reversed, there is an uninterrupted pressurization of the oil as it crosses into the peak pressure point. In order to carry a film of oil, that pressure rise is paramount. Anything that takes away from that pressure rise is an issue that needs to be dealt with.

Another post shows attempts to hammer in a new tang on the reversed bearing. I see more problems with doing that than advantages. The tang's only purpose is to locate the shell laterally in the saddle. If marked and carefully placed, the crush built into the bearings will maintain the bearing position.

Click to expand...

ssamalin said:

So the Franko6 bearing mod kit is unchanged, but when installing it there are instructions on reversing the lower bearings, which are (in or not in?) the kit? These lower bearings are stock which are simply installed reversed.

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No, you have to grind/file the tangs off the top and bottom bearings.

The top shell tangs are not impacted. They are put in normally.

Only the bottom shell is reversed, so only its tang is ground off.

I'm concerned about the tendency when starting for the bearing wanting to spin with the oil being squeezed out and having a dry start. It's one less thing holding it in place.

What about getting the bearings from a supplier with out the slot instead so it still has the tang?

nic_a_bod said:

I'm concerned about the tendency when starting for the bearing wanting to spin with the oil being squeezed out and having a dry start. It's one less thing holding it in place.

What about getting the bearings from a supplier with out the slot instead so it still has the tang?

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Well, that is a potential issue. One tang (the upper shell) and the bearing crush is still holding it. So there is less holding force available.

Note that even with two tangs, at least one person has reported a bearing movement equal to half the slots height.

I stlll plan to reverse the lower bearing, with no tang. Eventually this will give us one data point.

If you can find a manufacturer who will work with you on leaving the slot out for a decent price, let us know.

Dan,

The tang is not intended to be a stop shoe for bearings spinning. Let's face it. If that happens you got bigger fish to fry...

The bearing tang is a location tab.

If anyone prefers, I will provide bearing sets with the tang ground off. My only worry is that someone will either not grind the tang off completely or they will not locate the bearing correctly. What I do is use a magic marker on the saddles. Reinstall the bearing and scribe a line. Where you are able, scribe both sides.

So you know, the crush is what holds bearings in place. Reference your BEW/ BRM/ BHW rods. They have no tangs in cracked rods.

Frank is correct and knows what he saying the tang is just there to make sure the shell is in the correct position.

The bearing shells are larger then the hole in the bearing support, so when you assemble it all together the saddle crushes the bearing shells in the bore, its called an interference fit. This fit can be changed by either filling the bearing shell ends, or by filing the bearing support cap. This crush/interference is what 'seats' the bearing shells and 'holds' them in position, not the tang.

Hope this helps.

Mach1 said:

Frank is correct and knows what he saying the tang is just there to make sure the shell is in the correct position.

The bearing shells are larger then the hole in the bearing support, so when you assemble it all together the saddle crushes the bearing shells in the bore, its called an interference fit. This fit can be changed by either filling the bearing shell ends, or by filing the bearing support cap. This crush/interference is what 'seats' the bearing shells and 'holds' them in position, not the tang.

Hope this helps.

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I don't get the slight wear on the backside of the bearings then that I've seen pictures of.

nic_a_bod said:

I don't get the slight wear on the backside of the bearings then that I've seen pictures of.

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The wear could come from the reduced area on the head side trying to carry all the injection loading.

eddif