camshaft bearing tight

[tewfiks]

The Eagle racing cam that I purchased from CB performance for my type 4 rebuild is quite snug on the forward most bearing. Is this something that I should be concern with or shall I continue on with the reassembly with the thought it will seat itself with time.

The bearing itself sits in the car without issue, but with the cam installed it binds a bit to the cam. The original camshaft does not have this issue when placed in the case.
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1968 VW Bus
1972 VW Westy

[aeromech]

Is the cam bent?
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VW Type 2 1971 (3 ea.) 1978, 1969
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Capable of leaping tall buildings in a single bound

[Danwvw]

For sure find out why it's doing that before putting the case together. If it were the thrust bearing I would say just tap the cam on the gear end with a hammer to set it. That's what I do on the type 1's not sure about a type 4. They behave a little different with the oil pump in also. One test I do is with the crank in 1/2 the case with the cam and turn the crank so it's lifting the cam up where the two gears meet. The cam should not ride up out of place doing that test. But again my experience doing this is with a Type 1 engine.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[hazetguy]

i am reading this as though the flanges of the cam bearing are pinching in between the machined faces of the cam, a front-to-rear issue, and relatively common issue with aftermarket cams and some bearings.
if that is correct, you can *carefully* sand the face of the bearing for clearance.


gallery images by zac_atac44

[tewfiks]

YES that is the exact issue I am facing.
I will try and tap on it and see if that takes care of the issue.
The cam does ride up when turning as it sits currently.

Thanks
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1968 VW Bus
1972 VW Westy

[Danwvw]

Yes, Tap it a little to see if the thrust bearing will seat better and yes I have had to sand them too. Sometimes it's a bad cam gear or the crank gear does not match the cam gear very well, Is this the original cam and gear or is it a bolted on gear? The Cam gear should not have noticeable runout.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[bigbore]

I have also had the fit the thrust bearing before and heres some more fun facts.
I have been lineboring some type one case's the last few days and I always run my cam bore tool mine is old school it only cuts the center bore it just cleans it and make it round again mostly in the type ones the pounding the cast takes makes the cam bore oblong and when you put all new bearings in the cam gos tight so this is the fix.
now the new cam lingbores do all three bores but for the most part the center is the offender.

Also when putting a bolt on gear cam in a type 4 if you are using the oem style pump check to make sure the cam bolts don't hit the pump studs or nuts.
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where its cold and snowy

[Danwvw]

That is interesting, I did not know that center cam bearing could need so much attention, and I don't know any VW shops around me that can do that! But With the type 4 engine I bet that does not happen.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[SGKent]

This is what I found on my T4

End clearance with reground cam and mahle bearings .006"
End clearance with new webcam and mahle bearings .003"
End clearance with reground cam and Kolbenschmidt bearings .0045"
End clearance with new webcam and Kolbenschmidt bearings .0015"

Guess which combination I went with.
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Canned Water - the new California approved parts cleaner (except in a drought in which case rub it with sand).

George Carlin:
"Most people don't know what they're doing, and a lot of them are really good at it."

Skills@EuroCarsPlus:
"never time to do it right but always time to do it twice"

[Danwvw]

The thing I don't understand about cutting the cam bearing journals is wouldn't they become oversized? Are there oversize bearings?

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[tewfiks]

Brilliant. A little sanding with 1200 grit sandpaper and I now have a happy spinning camshaft.

Thanks a ton.
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1968 VW Bus
1972 VW Westy

[SGKent]

as to sanding Babbitt. Please don't.

Try this experiment - drop a stick of butter into gravel and sand, then rub it on something painted or on a piece of scrap glass. The softer butter picks up the abrasive and scratches things. Babbitt is softer than the sandpaper. It will pick up small particles of sand paper and forever grind on the cam thrust bearing surfaces. Instead use a Babbitt knife, even the flat blade of a barlow knife can be used to scrape the bearing to get clearance. It won't leave grit in the Babbitt like sanding will.
_________________
Canned Water - the new California approved parts cleaner (except in a drought in which case rub it with sand).

George Carlin:
"Most people don't know what they're doing, and a lot of them are really good at it."

Skills@EuroCarsPlus:
"never time to do it right but always time to do it twice"

[Danwvw]

You don't sand the bearing surface. Just the outside thrust flange. But usually they will seat with just the a tap on the end of the camshaft with a hammer one maybe 2 taps. Good tap not too weak but not a blow. But It's a good point about the Butter holding the sand. I would never put butter in sand.
The sand probably gets everywhere on all the bearings.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[bigbore]

[quote="Danwvw"]The thing I don't understand about cutting the cam bearing journals is wouldn't they become oversized? Are there oversize bearings?

The cutter is standard size it just makes the hole round again. the type 4 cases seam to not have this problem.
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where its cold and snowy

[SGKent]

[williamM]

The center cam bearing goes oval a very small amount and the case hammers out a little- so when the case is put back together -empty-it compresses a small amount. Then forms a round stock sized hole when the cutter is used ---that "gap" is pulled up tight when the case is torqued with the cam and bearing in there to original spec.. If really bad it can effect the cylinder seats and require a flycut on the block where the cylinders fit.

X2 kent- that piece is called a bearing scraper. Its a triangle file like tool but hallow ground to a knife edge on each side for clearing the babit away from oversized bearing.
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some days I get up and just sit and think. Some days I just sit.

opinion untempered by fact is ignorance.

Don't step in any!

[SGKent]

[williamM]

[Bulli Klinik]

Prior setting camshaft end-play, polish this surface. Many cams are very rough on the thrust surface. It's it's rough, it will continue to wear the thrust surface.

Once the thrust is polished, set the end play by surfacing the thrust bearing to .001. I use sandpaper, apparently others use babbit scrapers.

If you also de-burr the edge of the lobes, it's easier on the lifters.

Also a good idea to check your oil hole alignment while it's apart.

Good luck!
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PM me about quality metal-work on your vehicle.
Mike K
Bulli Klinik
Colorado Springs

[Hoody]

The last thing you want to do is introduce ANY type of "sanding" material to your aluminum bearings. As stated there are correct ways to clearance them. It's kid of like having sex on the beach.....if one single grain of sand is introduced excessive wear and painfull lessons are imminent.