Another BRM Cam victim

[Jnitrofish]

TonyJetta, I personally would be interested in knowing how your injector rocker adjustment pins and rollers held up. Like still smooth as a babies bottom or worn. Thanks.

bump ^

...
Those are silver followers sitting beside the failed black followers.
The silver followers are in BETTER shape than the black followers beside them.
...
eddif

Well, the silver followers in that engine are also the cooler intake followers so there is a clear heat factor in the silver followers being in better shape. They don't need as much oil to cool them down. I do agree however that in general the silver followers are more resilient if maintained properly.

Edit: I just looked back at those photos, those intakes are black topped as well eddif, see the black ring around the outer edge of them.

 

[aja8888]

eddif and hid3: Maybe you two should start a separate thread on the camshaft/bearing/oil/ wars?

It wouldn't clog this one up so badly with a lot of old information and photos.

 

[Jnitrofish]

eddif and hid3: Maybe you two should start a separate thread on the camshaft/bearing/oil/ wars?

It wouldn't clog this one up so badly with a lot of old information and photos.

lol its not a war, its preaching the gospel! You don't walk into a church and tell them build a new one cause they are clogging this one up with 2000 year old information!

 

[TonyJetta]

The injector pins and rollers looked fine; no apreciable wear. However, the injector lobes on the cam were scored rather deeply.

I'll take some pics later.

Tony

 

[eddif]

lol its not a war, its preaching the gospel! You don't walk into a church and tell them build a new one cause they are clogging this one up with 2000 year old information!

"Edit: I just looked back at those photos, those intakes are black topped as well eddif, see the black ring around the outer edge of them."

We might better ask Tony Jetta what the folllowers are (if he has enough experience to tell). Sometimes photos are hard to tell what is going on. The SBAtdijetta photos sometimes tend toward copper colors etc. And I was thinking that usually BRMs are a mix. VW might have done something unique. We will see if we can tell.

This is supposed to be a black and silver follower side by side, and you can see what looks like a black ring on it too.

What gospels are there lately:

Black Followers will solve all our problems
It is some little known oil in France that will help us
It is a new camshaft with better ramps
It is the cantilever relief bearings, heavier oil, better oil introduction point etc
It is a radial slot that does the thing
It is 15W-50 oil
UOA tells it all
UOA with teardown and inspection tells some of it
etc.

Some without pictures tests or anything. We have to be careful to not mess up a private truth with evidence though. LOL

eddif

 

[Jnitrofish]

The injector pins and rollers looked fine; no apreciable wear. However, the injector lobes on the cam were scored rather deeply.

I'll take some pics later.

Tony

OK that's awesome to know, I'm digging into my car tomorrow and it gives hope.

And I was thinking that usually BRMs are a mix.

My 12/2005 build date BRM had black topped intake and exhaust followers from the factory, I think later on they decided to go to silver intake and all black exhaust as SBA's car was a 04/2006 build. So since Tony has a black topped exhaust and a black line on the intake I figure his build date is somewhere near my old car. My 06/2005 BRM has all silver followers for the record.

Edit: Measured 1mm of nitriding around the side of the follower.

 

[eddif]

OK that's awesome to know, I'm digging into my car tomorrow and it gives hope.

My 12/2005 build date BRM had black topped intake and exhaust followers from the factory, I think later on they decided to go to silver intake and all black exhaust as SBA's car was a 04/2006 build. So since Tony has a black topped exhaust and a black line on the intake I figure his build date is somewhere near my old car. My 06/2005 BRM has all silver followers for the record.

Edit: Measured 1mm of nitriding around the side of the follower.

Photos?

eddif

 

[Jnitrofish]

Photos?

eddif

Of?

-Jnitrofish

 

[eddif]

I guess #s under bottom of follower will tell.

Tony what #s do the followers have underneath?

eddif

 

[eddif]

Of?

-Jnitrofish

All the followers you were describing. However, I do not have photos of everything and thus the question mark.

eddif

 

[Jnitrofish]

I'll get some photos of the all silver ones tomorrow and see if I can get some good ones of the black topped intake/exhaust with the 1mm of nitride coating on the side. I'll post a link when I have them.

 

[Bob S.]

lol its not a war, its preaching the gospel!

Gospel??? That one should grind away part of their cam bearings? That one should open their VC every "1,000 ; 2,000; 5,000 ; 10,000 miles etc."??? And take the bearing out to show people? Cams walking? Amen, Brother

Certainly not gospel. All the shouting, chanting and hoopla! It resembles a cult. Maybe even a snake handling one. No thanks, I will pass on that kool aid.

Personally, I would much rather see scientific engineering or real failure analysis with some analysis of all factors.

 

[TonyJetta]

Personally, I would much rather see scientific engineering or real failure analysis with some analysis of all factors.

Which is why I've been quiet about a lot of this. All I can do is analyze with respect to my failure and seeing pictures of other people's failures.

My analysis:
1) The apparent low levels of ZDDP in oil and the subsequent impact on flat tappet / solid lifter cams.
2) Going from 5W40 to 5W30 - reducing the oil's ability to maintain film tension
3) Potential impact of a marginal oiling system that may be designed to lubricate bearings AND spray oil onto the camshaft exhaust lobes.

Tony

 

[eddif]

Gospel??? That one should grind away part of their cam bearings? That one should open their VC every "1,000 ; 2,000; 5,000 ; 10,000 miles etc."??? And take the bearing out to show people? Cams walking? Amen, Brother

Certainly not gospel. All the shouting, chanting and hoopla! It resembles a cult. Maybe even a snake handling one. No thanks, I will pass on that kool aid.

Personally, I would much rather see scientific engineering or real failure analysis with some analysis of all factors.

At times I totally agree with you.

If VW had assigned 5 dynos, 5 engineers, and 10 workers to the PD project for two months to find a way to direct oil in the cam bearings I would not be doing any of my dance.

I did not reduce the load bearing area of the bearings. VW engineers did.

I avoid cutting in load bearing areas all that I can. The largest amount of babbitt surface area I cut is in / over the non load bearing areas that VW created. If the areas are not carrying load they are just being used as levers to either bend the bearings or cause cocking.

There is no great mystery. The bearings and oiling are the trouble spot that pushes the narrow lobes over the edge.

UOA is part of the picture. Used parts analysis is more of the rest of the picture / story. To you it seems dumb to look at wear. To an independent research facility testing oils "It is part of the job).

I am doing what VW should have done. I am a jerk from Mississippi and am well aware of that. If it seems a little hyper it is.

Might I ask what this was ?

" Gospel??? That one should grind away part of their cam bearings? That one should open their VC every "1,000 ; 2,000; 5,000 ; 10,000 miles etc."??? And take the bearing out to show people? Cams walking? Amen, Brother

Certainly not gospel. All the shouting, chanting and hoopla! It resembles a cult. Maybe even a snake handling one. No thanks, I will pass on that kool aid."

What are you asking for: Ignorance? No testing? Blind speculation? Waiting on VW to open up the dyno room hire engineers to fix the TDI PD problems (don't hold your breath).

I hear your chant. I hear your hoopla. I choose not to drink your kool aid of death of the PD.

I promote life of the PD. Everyone who presses on and finds something that works I cheer.

eddif

 

[eddif]

Which is why I've been quiet about a lot of this. All I can do is analyze with respect to my failure and seeing pictures of other people's failures.

My analysis:
1) The apparent low levels of ZDDP in oil and the subsequent impact on flat tappet / solid lifter cams.
2) Going from 5W40 to 5W30 - reducing the oil's ability to maintain film tension
3) Potential impact of a marginal oiling system that may be designed to lubricate bearings AND spray oil onto the camshaft exhaust lobes.

Tony

Goodness we just about agree.
1...VW had an oil to start with that was partly a CF oil (enough ZDDP)

2...Totally agree

3...Before the wear gets bad in the cam bearings, the stock set up oils the bearings and the followers. The design just allows that spray to decrease as the miles pile up. The spray exists for many miles then becomes a dribble.

I am looking forward to your photos and comments.

Edit; Here again (sorry) are the oil paths of stock bearings at low miles. The big crescent oil flow spots you want to stop, by doing babbitt cutting. The red arrows (follower flow / spray) you want to keep going, or move some of the flow to the upper oil slots where the flow will never be stopped.

The spray is the tiny red arrows going left or right or both ways. The oil goes between the cam bearing journal and the bearing and is kept narrow (up and down direction) by the direction the cam is rotating. This is the wedge area just before the hydrodynamic film. Described in the link.

eddif

 

[AD5GB]

Might I ask what this was ?

" Gospel??? That one should grind away part of their cam bearings? That one should open their VC every "1,000 ; 2,000; 5,000 ; 10,000 miles etc."??? And take the bearing out to show people? Cams walking? Amen, Brother

Certainly not gospel. All the shouting, chanting and hoopla! It resembles a cult. Maybe even a snake handling one. No thanks, I will pass on that kool aid."

What are you asking for: Ignorance? No testing? Blind speculation? Waiting on VW to open up the dyno room hire engineers to fix the TDI PD problems (don't hold your breath).

You failed to quote his last sentence in that post, which actually spelled out very clearly what he was asking for.

 

[Mach1]

Tony, I believe of alot of what you believe...I think are keys to the prevention of cam failure..I sell the ZDDP here at the shop and i ask every customer if they would like to use some and take a chance and roll the dice...

 

[TonyJetta]

Mach1, thanks for the confirmation.

I'll post pics later regarding the cam lobes.

Tony

 

[mobiledaveb]

Eddif -

Given all of the great work, background and investigation you have done, I'm wondering what type of oil do you recommend? Also any ZDDP additives? I'm having a new cam kit installed tomorrow and want to get off on the right foot...

Thanks!

db

If you yell at a person about to fall over a cliff, you might startle them and cause the fall.

I want to carefully walk up to you and suggest something. Please replace the cam bearings in your car. The copper is coming from the cam bearings IMHO, and experience. You only have about 100 miles to get this done. Soon that copper ring / or possibly rings turn into raw wear. I watched it happen on mine.

You have described what happened to me at 105,000 miles US. I replaced the cam bearings and lightly polished the copper off (it just wipes off with abrasive machinists cloth). The cam has no sign of the copper now 30,000 miles later (except the rollers kept a copper color on them).

If I have you standing away from the cliff edge; could I help talk you through getting new cam bearings in. In 100 more miles the tiny copper streaks were turning into raw wear marks. I parked my car till I could get the bearings in.

eddif

 

[eddif]

Eddif -

Given all of the great work, background and investigation you have done, I'm wondering what type of oil do you recommend? Also any ZDDP additives? I'm having a new cam kit installed tomorrow and want to get off on the right foot...

Thanks!

db

Given all the nice encouraging posts lately toward eddif, you sure are brave to ask me anything. Thanks for asking, and I appologise to Mach1 up front.

The original oil for the PD was a partially rated CF oil. I am just now understanding what that means. The CF oil (and I would have to look up where this statement came from) is for IDIs with copper, brass, bronze (?) (I believe) bushing etc. We have problems with copper so it is possible the oil met those needs. Everything changes and so now the additives are changing.

I support Mobil 1 TDT 5W-40 oil, as a minimum viscosity oil. I also support using Mobil 1 15W-50 mixed with the TDT for hot weather. What ratio is being tested now. I tend to test what I talk about and I have almost straight 15W-50 in the car now.

The testing thing on ZDDP is interesting. If I am going to make a statement I am going to try it. No use to make glorious eddif statements and not give it a whirl. I tried 5000 parts per million of ZDDP to see what would happen (Hot Rod break-in level for flat tappets and high spring levels). I had copper all over everywhere. Streaks were forming on many lobes. I got a sneaky idea that this is related to ZDDP. Railroad engines (some) use under 30 parts per million ZDDP. Not 1200 but below 30. It is my opinion (not worth much sometimes), that due to the copper being forced into contact with the cam journal lobes we can not tolerate much ZDDP. I think ZDDP bonds to the cam journals at high levels. How much ZDDP....I do not know. That is what the CF oil might have helped. I do not know. So I bought 5 bottles of ZDDP that is sitting on a shelf. With thicker oil keeping the cam bearings from wearing, and giving a thicker hydrodynamic film, I may use it later.

I do not know what the reaction of black followers is to ZDDP. Sorry I will not hazard a guess. I did tell the long ZDDP test results.

Good luck. Little idle time then bring RPMs up.

eddif

 

[AD5GB]

Keep in mind all that there's more to elevated idle speeds for flat tapped break in than just supplying lubrication. It is also about encouraging and establishing a wear pattern that promotes lifter rotation (rather than scuffing). It's more easily achieved at elevated break in idle speeds and crucial to long life of a flat tapped (solid or hydraulic) camshaft. Those initial minutes can make or break the difference. But to quote Harv; *** do I know eh?

 

[Dimitri16V]

Don't use more than 1800 ppm of ZDDP. It attacks iron

In my own conclusion , there are few things to blame.

the engine design ( too much stress on cam bearings ) , narrow cam lobes , possible underhardened cams and weak 505.01 oil

The lobes wear out first , then the lifters since they are not rotating anymore.

at the end , even with a properly hardened cam and superb oil , the inevitable cam/lifter wear will show up . It might take 300K but it will happen

 

[Dimitri16V]

Keep in mind all that there's more to elevated idle speeds for flat tapped break in than just supplying lubrication. It is also about encouraging and establishing a wear pattern that promotes lifter rotation (rather than scuffing). It's more easily achieved at elevated break in idle speeds and crucial to long life of a flat tapped (solid or hydraulic) camshaft. Those initial minutes can make or break the difference. But to quote Harv; *** do I know eh?

you are absolutely correct.
There is a GURU here with his own TDI shop that claims elevated rpms are not needed after he replaces PD cams

but as you said , *** do I know , I am no TDI guru ..

 

[AD5GB]

you are absolutely correct.
There is a GURU here with his own TDI shop that claims elevated rpms are not needed after he replaces PD cams

but as you said , *** do I know , I am no TDI guru ..

It's a simple matter of physics, coupled with microscopic analysis; let alone decades of experience of those that have learned the hard way. But then *** do I know eh? (to quote Harv) Did it for too long (almost 20 years) and yet nothing has really changed. I'd say "Later" but then Harv would surely slam me!

Opinions vary greatly. When it comes to camshaft failure opinions abound. A professional cam maker believes to have found a significant defect in the base circle-to-ramp transition on the lobe profile of the BEW/BRM sticks. He's been grinding cams for many many years. Has the technology. Has the capability. Has the theory and mathematics to back up his theory. Nobody listens.....

 

[Dimitri16V]

I am not sure about the ramp profile , my scirocco cams have sharper profile and they have not wear out yet @ 185K
It may sound like anecdotal evidence but I have not any significant wear in my PD and also have inspected another PD with identical mostly highway driving life with even more mileage on it possibly 230K by now.
I have not seen any significant wear on that one either.
High rpms keep those lifters rotating ..

Anyways , I am sure the local gurus or engineers will chime in ...

 

[AD5GB]

I haven't looked closely at the profiles of either the Scirocco sticks nor that of the BRM/BEW motors. I do take heed however in the knowledge and experience of those who grind cams for a living and have done so for 20+ years. Those people have helped me over the years in selecting the appropriate valvetrain components successfully for any application in which I chose to endeavor; and have never failed me. I don't have the equipment that they do to closely analyze the lobe profile of a camshaft and consider the subtle differences as to something like valve bounce and how it differs between a solid vs. hydraulic lifter stick. That said I've not yet looked at my BRM cam but so far have had little reason to. I will B4 T/B change time and if needed will change it out, but now that there's a choice....... { you fill in the blanks }

 

[hid3]

So the break-in after cam replacement should be made by holding high RPMs, right?

 

[TonyJetta]

So the break-in after cam replacement should be made by holding high RPMs, right?

That's what I've always been led to believe for the last 20 years. >2000 rpm generally keeps full flow oil to the cam bearings and lobes.

Tony

 

[hid3]

Tony, thanks. And the last question: does this apply for both, flat tappet sliding follower engines and flat tappet partially rotating follower engines (like the TDI PDs we have)?

 

[TonyJetta]

Tony, thanks. And the last question: does this apply for both, flat tappet sliding follower engines and flat tappet partially rotating follower engines (like the TDI PDs we have)?

AFAIK, since the early pushrod V8's, circa early 1950's, and subsequent 4 and 6 cylinder engines have all been designed with rotating tappets, where possible. The exceptions are flat tappet overhead cam engines, like the 2.0/2.3 pinto/cortina, and roller tappet-cam engines.

Technically, the VW design is referred a direct acting hydraulic tappet camshaft design.

Tony