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Thurust bearing taken out on new build. Help

I’m curious

Are you using studs for the mains instead of bolts?
If so was the block align bored with new studs? I heard that is necessary when switching out the bolts for studs.
 
Just did some googling to get outside input.
Possible causes mentioned:

-Too much pressure/resistance in the trans pump. Pressure was checked for this
-bad crank; be careful of using the same crank chewing the thrust again. This guy chewed up three thrust bearings.
-too much end play clearance
-*bad initial start up with lack of oiling and/or with contaminants in the oil. I have witnessed youtube builders disassemble new oil pumps and saw the amount of contaminants inside so they are cleaned and reassembled. Was the oil pump primed before start up? Oil passages may not have been cleaned before initial assembly. Lack of assembly oil?
-*Ballooned converter. This was mentioned in previous posts. There should be clearance between flexplate and converter.
-* Misaligned/out of square block to trans. Dowel pins could have to be changed with offset pins used. I have done this with one of my blocks with 4 speed bellhousing when I suspected input shaft misalignment and/or possible clutch/throw out bearing problems

Trans converters, pump pressure/resistance, bad alignment & bad start up were the most popular causes mentioned. Some felt most times it's the trans and others the engine so I guess it will come down to deducting one thing at a time and checking everything.

Hope this helps. Good luck
 
This is what I do to all my latest builds. But I can’t take credit for it. RAMM clued me in. Just make sure the hole intersects with the oil passage in the block. Of course this works as long as all other specs are in spec. To be clear just drill the rear side as that’s where the thrust is. Kim

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still waiting to hear from engine builder. I will respond with any and all results, findings.
 
Having built my own engines in the past I found that post about drilling a hole through the thrust bearing interesting. Never heard of it.
I did some googling and found these posts about thrust bearing issues and how others have "resolved" it. Some causes they discuss too. There doesn't seem to be one "proven" method agreed upon.

Among them:
-filing bevels/chamfers instead of drilling holes
-purchasing specific thrust bearings that seemed to add oiling
- drilling most of the way .06 and then finishing with a .03 drill...
-once again checking TC pump pressure/resistance
-adding a roller bearing I believe was in the front? of the crank
-discussions about effect on oil pressure and rod bearings when drilling the hole through the thrust bearing

If you care to partake:

Destroying thrust bearings - LS1TECH - Camaro and Firebird Forum Discussion

Thrust Bearing Mod - PY Online Forums - Bringing the Pontiac Hobby Together

thrust bearing oil hole.
 
I have drilled the trust on 10 or so motors. I use a HV oil pump. Right around 70 lbs cold and 45 lbs hot. Thats with 10W30 oil. Kim

What kind of builds are these motors you are modifying oil thrust bearings? What application/power range are we talking about when someone should feel it necessary to do this?

I have read articles about stroker engines but don’t recall anything about extra thrust bearing protection.

Or is this just insurance/piece of mind?

Above 500 hp? 600? Just racing? Supercharged?

For years I have built 450ish to 500 hp motors and never had a thrust bearing failure.
They were mostly manual transmission applications if that makes a difference.
 
still waiting to hear from engine builder. I will respond with any and all results, findings.
Can we find out exactly which bearings they were? Fairly important part of the conversation.
 
What kind of builds are these motors you are modifying oil thrust bearings? What application/power range are we talking about when someone should feel it necessary to do this?

I have read articles about stroker engines but don’t recall anything about extra thrust bearing protection.

Or is this just insurance/piece of mind?

Above 500 hp? 600? Just racing? Supercharged?

For years I have built 450ish to 500 hp motors and never had a thrust bearing failure.
They were mostly manual transmission applications if that makes a difference.
Anything 400 hp and up. Yes it’s piece of mind since I’ve seen a few thrust beating knocked out. Kim
 
My race motor uses unmodified Clevite 2233HG mains. Race converter that is always loaded hard at the starting line. 5 w 25 oil. Never had a thrust issue in 11 years over 1000 passes. Motor makes around 900hp.
Doug
 
Having built my own engines in the past I found that post about drilling a hole through the thrust bearing interesting. Never heard of it.
I did some googling and found these posts about thrust bearing issues and how others have "resolved" it. Some causes they discuss too. There doesn't seem to be one "proven" method agreed upon.

Among them:
-filing bevels/chamfers instead of drilling holes
-purchasing specific thrust bearings that seemed to add oiling
- drilling most of the way .06 and then finishing with a .03 drill...
-once again checking TC pump pressure/resistance
-adding a roller bearing I believe was in the front? of the crank
-discussions about effect on oil pressure and rod bearings when drilling the hole through the thrust bearing

If you care to partake:

Destroying thrust bearings - LS1TECH - Camaro and Firebird Forum Discussion

Thrust Bearing Mod - PY Online Forums - Bringing the Pontiac Hobby Together

thrust bearing oil hole.
Back in 60's/70's Pro Stocker's were losing thrust bearings. The cure was as you file the oil grooves.
 
Back in 60's/70's Pro Stocker's were losing thrust bearings. The cure was as you file the oil grooves.

So we are talking about high output horsepower. I’m not sure what hp a Pro Stocker generates.

I was trying to figure exactly where they did file the groove/chamfer. There seems to be a few different ways. The pictures are a bit vague.

File across top back edge?
Just the top back edge?
So what is the pathway?

Today’s mopar engines have a good amount of choices to get well over 600 horsepower with bolt on kits like TrickFlow. I don’t see any mention of thrust bearing modifications or even the use of saddle girders or high strength rod cap bolts. But then again the first users are the trial run guinea pigs.
 
Where I read that said file the stock grooves deeper starting a little off crank bearing surface down to edge. Wouldn't go crazy where it tapers down on edge. The process of thrust bearing install, I install crank and caps thrush main cap slightly tight but will shift when I take a large screwdriver and jam crank back to square up thrust surface. Leave screwdriver in and tighten thrust main (center main BBs) to torque spec. then torque the rest of mains if you have done already.
My memory is fuzzy on whether to jam crank forward or backward hope someone say the correct direction. Will edit to correct if I'm in error.
 
No need to file slots on the Clevite MS2233HG . They are notched already.
Doug

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I don't recall seeing thrusts that aren't notched. Sealed power 4095M sitting here, check.
 
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