new build and it walked

[jeremy19984g63]

ok just finished up a rebuild last night. Done everything by the book, and definitely not my first build. I used the trick of installing the engine into the car and used the clutch pressure to set my thrust bearings, and then torqued the mains. Ran great, had great oil pressure. Well guess what it crankwalked today. Just got done pulling it out, and pulled the main caps. The bearings look great. No sign of dirt contamination at all, but the thrust surface looks horrible. I checked all oil clearances during build. i dont see how this could have happened? also the crank was new. So any ideas guys?

 

[4g64fiero]

Did you replace the oil squirters?

 

[jeremy19984g63]

no i did not

 

[Artago]

The bearings look great. No sign of dirt contamination at all, but the thrust surface looks horrible.

Can you post some pics?

 

[jeremy19984g63]

Will do that in the morning

 

[4g64fiero]

I will say this, thrust bearing failure is accelerated dramatically by lack of localized oil pressure. This can happen if that squirter is sticking open due to it relying on the same oil galley as the main bearing attached to the thrust bearing. The thrust bearing doesnt get alot of oil to start with. Thats the only reason I mention it.

 

[Artago]

I will say this, thrust bearing failure is accelerated dramatically by lack of localized oil pressure. This can happen if that squirter is sticking open due to it relying on the same oil galley as the main bearing attached to the thrust bearing. The thrust bearing doesnt get alot of oil to start with. Thats the only reason I mention it.

I have heard this too.... and I'm sure the ACT2600 PP is helping to make the situation worse. I've just switched to the ACT2100 PP (but it's not installed yet).


jeremy19984g63.... i'm assuming you are going to rebuild.... might wanna think about replacing the oil squirters.

Tom

 

[jeremy19984g63]

This block that i just built was a 1995. i will not be rebuilding it again. Im going to build the engine that came in my car, because it is a 1998 year block and has thrust washers.

First pic is front side of thrust. Second is of the flywheel side of thrust. less than 100 miles!!!

 

[Artago]

How does the crank look? Do you have pics of that?

 

[jeremy19984g63]

Yes the thrust surface of the crank is just as bad, no I don't have a picture right now.

Just went and took some pics.

 

[Strm Trpr]

I'd have the crank polished and inspected.
Have the width of main #3 measured.
Then measure across the flats on a new thrust bearing.
If the difference is .007" or less, then you're good to go to reuse that crank.

I've read that some people like to deburr their thrust bearing flanges right at the parting line on the planar faces.
They use a piece of wet/dry sand paper around a 1500-2000 grit I believe and place the sand paper on a piece of glass or a very flat surface.
Next they hand dress a nice little chamfer on those edges of about .1" long by 15-20* or so.

You should always knock out the old oil jets.
Especially if the block is at the shop getting machined.
Once the block is all cleaned and ready for reassembly then new oil jets should be installed.

How old is the oil pump?
Was it inspected and within tolerances?
The Haynes Manual covers the inspection process.

Also, you didn't happen to stud the mains did you?

I've never heard of using the clutch to put pressure on the thrust surface while torquing the main bolts....
Not too sure I'd advocate that method.

 

[jeremy19984g63]

No this crank is shot. It does not look to bad in the pic, but the scarring is deep!

 

[GSTTOBEAT]

You should go ahead and just put a 6 bolt block in while it is apart. Keep away from those heavy duty pressure plates. I had the same problem just after a rebuild in my 95. Then I went and bought an EVO3 engine and at 400hp and 4 years later I did not have 1 problem with the thrust bearing.

 

[MidShipCivic]

Thing is you say you've done everything by the book... yeah that says a lot but that doesn't say
anything about the assembler.

Did you know about that thrust surface BEFORE?

The bearing is softer than the crankshaft surface and now that you put a new bearing surface to wear upon it accelerated the process.

6 bolts don't matter cut the biblical mess, point in case if the thrust surface on the crank is bad the engine will walk in about 4 days.

Bad crankshaft.
Oilcase side (6 bolt) I raced on this engine and and this side was perfect yet the other side was not.

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Flywheel side (6 bolt)

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[jeremy19984g63]

hey MidShipCivic

Like i stated IT WAS A NEW CRANKSHAFT!!

and dont butt in with useless info. please

 

[MidShipCivic]

hey MidShipCivic

Like i stated IT WAS A NEW CRANKSHAFT!!

That doesn't mean a thing.

hey MidShipCivic


and dont butt in with useless info. please

Excuse you? That's why you're on here with a walked engine huh ?

I posted the most relevant info that I've experienced you should follow your own mouth and not post useless comments.

For fun I have 7 bolt bearings out of a perfect engine I just put together with out doing any actions of of installing it in the car that are stellar.

By ''New'' crankshaft what is new about it? New to you; Reconditioned, remanufactured or MD-Fill-In-the-blank.

1. If it was an oil pressure problem that bearing wouldn't be spotless

I hope that you'll re-evaluate your actions and talk to me in a troubleshooting matter.

 

[jeremy19984g63]

Thing is you say you've done everything by the book... yeah that says a lot but that doesn't say anything about the assembler.

6 bolts don't matter cut the biblical mess,

This is what i was talking about. This kind of talk was not intended to help me nor anyone else.

As for oil pressure, I know i had good pressure, but like someone stated before if the oil squirter was stuck open then that would decrease pressure to the thrust surface. After reading the article from the guys at magnus, this is most likely what has happened.

As for the crank, new core from topline.

 

[MidShipCivic]

This is what i was talking about. This kind of talk was not intended to help me nor anyone else.

As for oil pressure, I know i had good pressure,

IF you READ the post above mine saying ''just a get a six bolt''.

As for the crank, new core from topline.

Ah real good company, after all I've had 3 oil pumps go from their machining qualities.

but like someone stated before if the oil squirter was stuck open then that would decrease pressure to the thrust surface. After reading the article from the guys at magnus, this is most likely what has happened.

Magnus article did not conclude that the squirters were a problem if he gave you
numbers with 1g squirters opening at different pressures what would you say then?

But.

You concluded it to oil squirters ? Magnus article shows you that the galley is no different with the exception of ball spring type squirters, secondly oil comes out of your bearing with mechanical force squeezing oil on to the thrust bearings if the pressure was bled out of that squirter your bearing would show that and your bearing IS SPOTLESS.

 

[jeremy19984g63]

i dont know. took apart my scm6152 and it had shavings in it. i have had this car since it was new so am starting to think its time to just give up. i hate the color i painted it anyway. part it out maybe!

 

[MidShipCivic]

Don't give up !

Just pick up a nice unharmed OEM 7 bolt crank new bearings clean that block nice, recheck end play moly lube the place up and you'll be fine!

 

[jeremy19984g63]

well i fried my built engine. this was going to be my low budget build, so you can see why im so frustrated with the whole damn thing

 

[red_devil]

You should go ahead and just put a 6 bolt block in while it is apart. Keep away from those heavy duty pressure plates. I had the same problem just after a rebuild in my 95. Then I went and bought an EVO3 engine and at 400hp and 4 years later I did not have 1 problem with the thrust bearing.

EVO3 is a 7 bolt there bud

 

[4g64fiero]

secondly oil comes out of your bearing with mechanical force squeezing oil on to the thrust bearings if the pressure was bled out of that squirter your bearing would show that and your bearing IS SPOTLESS.

Yeah there was no oil starvation having looked at that bearing. I would definitely count out the oil squirter at this point.


So what was your endplay when assembled?

 

[jeremy19984g63]

endplay was right at .004

 

[Doubleot]

Don't give up man. You could always just find a 6 bolt from someone parting their car out and rebuild that on a budget. But if your sick of car" I know I have been" Then good luck with the part out.