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Cam Bearing

Marv02

Well-known member
Joined
May 4, 2010
Messages
472
Location
California City Ca
Corvette
1986 C-4 Corvette
I pulled my Old cam out it had 3000 miles on it to put a little hotter cam in it.
I found the front Cam bearing has some Galling of the left upper about 3/4 inch long Ya I know not good.
Can I replace the front cam bearing when the motor still in the car and Do they make a tool for this.
Or is it time to pull the motor Again.
Murphies law I telling you.
The car did not knock or anythng.
 
I was thinking And a 383 Stoker kit only $700.00 On E-Bay Hint Hint.
New bearings crank rods.
But I dont want to buy anouther set of Injectors I like to use my 24s And will my cam I just ordered be to small for a 383 I am also in CA and have to play the smog game.
Lunati 60101 RPM Range 1000 to 5500 Lope sep 112 Lift .484 Ex .496 Duration 213/219@.050 Adertised 256/262.
If so I need to sent back as soon as it gets here.
Oh ya I figuring with flat top pistons and my 62cc heads I should be at 10.5 to 1 Ish you think that will be to much for a street motor on pump gas the heads are aluminum.
 
I called Lunati Cams and asked the cam I have on order and it on it way how will it act in a 383 motor he said it will move my operating range of the cam down 100 RPM's and it should work fine.
I dont race the car but it will be a tourqe monster thats for sure what I want for the street.
so I have a RPM range of 900 to 5400 thats works for me Plus I am going to use 1.6 rocker arms that should help give it some more HP on top.
So it mite still end up beening a 1000 to 5500 cam.
 
Bearing Up date

Pulled the motor pull the pan.
Front main cap bearing Okay but could be better 2nd some marks no big deal 3rd Well, I could see alot of brass Hum the motor only has 3000 miles on it it has worn though the first coating already Not good.
If the motor was a old motor I could understand the worn parts but only 3000 miles I think it ws a time bomb waiting to happen.
It 385 time I not going to change it I dont want to pull the motor again any time soon.
 
What do you guys think run a quick hone my self I hate to pain a machine shop to do a 15 minute job just to scuff up it for the new rings.
Or screw it dont hone just put in as is I know it take longer to seat the rings but I dont want take metal off the cylinder wall if I dont have to
 
What do you guys think run a quick hone my self I hate to pain a machine shop to do a 15 minute job just to scuff up it for the new rings.
Or screw it dont hone just put in as is I know it take longer to seat the rings but I dont want take metal off the cylinder wall if I dont have to


Dammmm Marv !

this thing snake bit or what?


If you can;t find a good reason for this extremely high wear, you got to tear it down and find a reason, otherwise your next box of parts will be wasted too.
Whats wearing? cam bearings and mains? what about small end rods?
Somethin ain't right...is there an oil passage thats blocked and not letting oil flow thru to everything? I've seen drill bits broken off in oil ports, RTV sealant, other junk stuck in the hole where the oil was not flowing. It still made pressure, but the flow was next to nothing to part of the motor. The result was high wear...

You might as well start over. At 3000 miles you should'nt see ANY metal...Hell, I've got some old mains that came out of my original motor that had 150-170,000 miles and the shop wanted to know why I was tearing apart a good motor ! They spec'd closer to new than the allowable. I give ProLong credit for that, but thats another story...

You need to find what the problem is and ID a cause for the wear and correct it once and for all.. That much wear this soon?...your wife is gonna start asking questions pretty soon...! :ugh and then its good bye car parts !
 
More I tear in to it uglyer it getting.
Every main crank Journal on the crank has groves in it so far I have pulled 1 rod cap not bad looking so far semi.
I looks like it has a oiling problem to me.
 
More I tear in to it uglyer it getting.
Every main crank Journal on the crank has groves in it so far I have pulled 1 rod cap not bad looking so far semi.
I looks like it has a oiling problem to me.

Looks like you are getting lucky in lots of ways...this coulda gone on and ended up throwin a bone out the side of the block...seized...no tellin.
Glad you tore it down.
Now go thru it one piece at a time and double check each piece. You'll find a reason, but do not reassemble until you DO find a reason why its eating bearings this quick.

Was the pump pick up screen too far away from the bottom of the new pan? or jambed against the very bottom?
 
I going to a good shop that back up there work have them build a 383 short block tell them and show them what has happen.
The short block now had no warrenty on it now I see why.


Looks like you are getting lucky in lots of ways...this coulda gone on and ended up throwin a bone out the side of the block...seized...no tellin.
Glad you tore it down.
Now go thru it one piece at a time and double check each piece. You'll find a reason, but do not reassemble until you DO find a reason why its eating bearings this quick.

Was the pump pick up screen too far away from the bottom of the new pan? or jambed against the very bottom?
 
Were top and bottom caps worn the same? You didn't have alternating top and bottom wear from one main to the next? Be checking line bore.

One other thing, were you using an AC Delco oil filter. The new filters now have plastic cage on the inside. A friend of mine with a sprint car had some oil pressure problems. He decided it was about time for a tear down . When he took it apart he found bits of plastic in the oil passages. The cage in the oil filter had come apart. If he hadn't tore it down when he did it would have cost him the entire engine. Have heard of others having similar issues.

No more AC filters for me.

Scav
 
I going to a good shop that back up there work have them build a 383 short block tell them and show them what has happen.
The short block now had no warrenty on it now I see why.


Are you anywhere near Ventura?

I know of a great shop there....they did my block, bored, all machine work, balanced the rotating assy and returned it sterlized and better than new. Shrink wrapped for freshness....
 
I about 1 hour drive away I drive there if a good shop.

Are you anywhere near Ventura?

I know of a great shop there....they did my block, bored, all machine work, balanced the rotating assy and returned it sterlized and better than new. Shrink wrapped for freshness....
 
Napa 7099 filters gold filter only.

Were top and bottom caps worn the same? You didn't have alternating top and bottom wear from one main to the next? Be checking line bore.

One other thing, were you using an AC Delco oil filter. The new filters now have plastic cage on the inside. A friend of mine with a sprint car had some oil pressure problems. He decided it was about time for a tear down . When he took it apart he found bits of plastic in the oil passages. The cage in the oil filter had come apart. If he hadn't tore it down when he did it would have cost him the entire engine. Have heard of others having similar issues.

No more AC filters for me.

Scav
 
Down to the bare Block

This what I have found.
Main cap #1/2, scracthes on bearing upper and lowwer liveable but not 100% where I would of liked to see.
Cap #2/3/4, lowwer bearing smouth but worn to brass some scacthes Upper some deep scacthes not pretty.
All main bearing and rod bearing areas on crank scacthes.
Rods bearings everyone scracthed upper an lowwer.
I going to bring the block down to the local engine shop with the main caps in place with the bearings installed so they can take a look at them and telll me whats up.
#6 Cylinder had nick on outboard about 1/4 long from top of deck straight down I think it above the ring land area.
The motor at .040 over bore now I see what the machine shop said on that.
Next How much for the machine work if over $700.00 I order a 383 block already to go.
 
I about 1 hour drive away I drive there if a good shop.


See if you can find FAINS Machine shop/performance shop. Its right off the 101. They do tons of boats with Ventura harbor 3 miles away. Lots of badass boats around there...

Fains machine Shop

Its been a few yrs but they did an excellent job on my block. I almost felt guilty taking the shrink wrap off and getting it dirty...I watched the guy weighing my parts for balancing...they were very precise. At this point it might be best to do an exchange deal...
 
Thanks I just shot them a E-mail asking how much and can I drop it off this comming friday.

I just scrard of he places around here so many bad stories like my transmission shop LOL.

See if you can find FAINS Machine shop/performance shop. Its right off the 101. They do tons of boats with Ventura harbor 3 miles away. Lots of badass boats around there...

Fains machine Shop

Its been a few yrs but they did an excellent job on my block. I almost felt guilty taking the shrink wrap off and getting it dirty...I watched the guy weighing my parts for balancing...they were very precise. At this point it might be best to do an exchange deal...
 
It going to cost about $1200.00 In parts more or less.
Gaskets Ect Included in price.
 
It going to cost about $1200.00 In parts more or less.
Gaskets Ect Included in price.

Thats not far out of line. I paid more but I had other work done too.

Like I said before, its been several years since they did my block but its held up and the work was clean, neat and precise back then. I really can't say whats going on there these days. Thats gonna be up to you to decide.
I hope it works out.
 
Junk everything is junk.

I got up this morning to do some work on the block start cleaning it up before I go to work woirking nights.
The stinking block cracked #3 cylinder from a head bolt hole to the bore it looks like it has been sleeved before But I not going to reuse this block.
I never buy a motor form Blue Print motors again junk.
Now do I buy anouther short block buy just a 383 block and build it I have to start looking now.
 

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