[TnVTX]

Originally Posted by george kujanski

I've been reading this and have a stupid question. Could someone be determining the bearing clearance as the bearing diameter minus the crank diameter, or what I think is the correct way, namely the gap between the bearing and the crank such as measured with Plastigage?

Using the spec number in the first case will be too little clearance. Any possibility in this? I know it's a dumb question, but......

George

I was using plastigauge just as a ballpark indicator... So, those readings were open to interpertation. (I don't have a bore mic to check rods with bearings in it).
The race engine shop set the clearances to the specs that a local, older, long-time Pontiac racer has all his motors setup at (Bob Crawford if anyone might know him). Bob has built several of these Eagle crank'd motors for his drag racing customers, so the machine shop trusts his recommendations. (Bob uses this same machine shop to perform the machining for his motors).

[uneasyrider]

Just a question/thought...

Too loose plus not enough zinc in the oil? I whipped through the past post and in that quick glance I don't see anything said about EOS used in breakin. Was it used? I've been hearing so much about this Zinc thing that I'm a bit nervous about it.

[HWYSTR455]

Couple things to check is:

1) Trans shaft/crank clearance, as well and making sure the converter is fully seated.

2) bellhousing alignment.

These being way out could cause a side load on the crank, and could in theory cause these types of problems.

3) Top rod bearings in the top of the rod, bottom bearings in the bottom. The rod bearings in those kits HAVE to be installed correctly, or the chamfers won't line up correctly. They're marked top & bottom on the boxes, though don't believe the ebaring themselves are marked. If you lay them out during assembly, they can get mixed up. Even an experienced engine builder can make this mistake.

I say on the next go around, just for GP, don't bolt up the converter, do the break-in, and check the filter for bearing material. This kind of damage at 100 miles means it's from startup on, one would think.

It's a little odd that both rod & mains are getting trashed, IMO, which to me would think it's a saddle alignment issue. But if it's been checked, and turns freely during assembly, doesn't seem the case. Maybe get a straight edge and check it to be sure.

On the cam bearings there, my first thought would be alignment there too.

As for measuring clearances, what I did to get rod & main clearances was I assembled the crank in the block with all main beraings in place, torqued to the correct value, then disassembled. Then I torqued the caps on the block, measured the inside, measured the bearings, then measured the crank to get main clearances. I believe you can even reassemble with the bearings in the caps and measure total, since after squish, they should be in the correct location in the cap & block, but I chose not to do it that way. I repeated the process with the rods, assembled, torqued, disassembled.

Here's the curious thing. My new stroker assembly which I did the start up on in Jan did the same thing, waxed a bearing(s). At about the 5 hour mark, on the 3 oil change, I cut a filter open and found bearing material. I haven't taken it apart yet (time constraints), but I suspect during reassembly of the rods after measuring clearances, I may have swapped a top & bottom shell. I can't count how many Pontiac engines I've built & assembled, and am flustered I had issues with this one. The machine work on the parts were dead one, and verified, which is why I think it was an assembly error. Hearing that others are having bearing issues is starting to make me wonder though....

[TnVTX]

Originally Posted by HWYSTR455

Couple things to check is:

1) Trans shaft/crank clearance, as well and making sure the converter is fully seated.

2) bellhousing alignment.

These being way out could cause a side load on the crank, and could in theory cause these types of problems.

3) Top rod bearings in the top of the rod, bottom bearings in the bottom. The rod bearings in those kits HAVE to be installed correctly, or the chamfers won't line up correctly. They're marked top & bottom on the boxes, though don't believe the ebaring themselves are marked. If you lay them out during assembly, they can get mixed up. Even an experienced engine builder can make this mistake.

I say on the next go around, just for GP, don't bolt up the converter, do the break-in, and check the filter for bearing material. This kind of damage at 100 miles means it's from startup on, one would think.

It's a little odd that both rod & mains are getting trashed, IMO, which to me would think it's a saddle alignment issue. But if it's been checked, and turns freely during assembly, doesn't seem the case. Maybe get a straight edge and check it to be sure.

On the cam bearings there, my first thought would be alignment there too.

Here's the curious thing. My new stroker assembly which I did the start up on in Jan did the same thing, waxed a bearing(s). At about the 5 hour mark, on the 3 oil change, I cut a filter open and found bearing material. I haven't taken it apart yet (time constraints), but I suspect during reassembly of the rods after measuring clearances, I may have swapped a top & bottom shell. I can't count how many Pontiac engines I've built & assembled, and am flustered I had issues with this one. The machine work on the parts were dead one, and verified, which is why I think it was an assembly error. Hearing that others are having bearing issues is starting to make me wonder though....

1) Automatic is the same one that came off this 120,000 mile motor. The motor had received a stock 400 rebuild about 40,000 miles ago, and everything looked great when I tore it down.
But, I had changed to a "L-88" converter I had laying around when the first stroker kit was put in. It had plenty of clearance, but, after the first bearing failure, I thought it's possible that conveter might be balooning. So... I bought a TCI conveter with anti-balooning plate, it also has plenty of free play when pulled up to the flywheel. So, the nothing is jamming into the rear of the crank.

2)Since this was the original trans that came with this motor and car, I doubt there could be a bellhousing alignment problem.

3) I had been made aware of these H series bearings with the bevel cut for the crank's radius cut. So, I paid special attention to the installation of the H-beam rods and bearings. The second time, the race shop assembled the short-block. So, on tear down, I made sure they had oriented the bearings correctly (and they were right).

Those bad cam bearings were from another poster, not mine. My cam bearings were perfect.

Be sure to let me know what you find out, backwards bearing, or another mystery bearing eater

[TnVTX]

Originally Posted by uneasyrider

Just a question/thought...

Too loose plus not enough zinc in the oil? I whipped through the past post and in that quick glance I don't see anything said about EOS used in breakin. Was it used? I've been hearing so much about this Zinc thing that I'm a bit nervous about it.

On the first round, I used a zinc additive sold by the race engine shop for cam break-in. I also used the "old" formula of Rotella which also had some zinc in it also.

On the second round, I left out the cam break-in additive since the cam had already been broke in. I did add about a 1/2 bottle of Lucas per recommendation from a Top Fuel engine builder. (It also makes for a good assembly lube as well).

I talked to the Royal Purple tech guy, and, they still put plenty of zinc in their oils. But, I was going to wait until the motor was broke in before putting it on Royal Purple synthetic... But, instead of broke-in, all I can get is just broke!

[guidos]

Just a thought, I wonder how much of the metal from the last motor failure was still in the lifters. Somebody mentioned it to me once and I was wondering what others think. I never really thought of it but I guess if there was metal in the oil the lifter would see some of it.
Thoughts?

[uneasyrider]

Originally Posted by TnVTX

...I talked to the Royal Purple tech guy, and, they still put plenty of zinc in their oils. But, I was going to wait until the motor was broke in before putting it on Royal Purple synthetic... But, instead of broke-in, all I can get is just broke!

Good to know about the Royal!

I'm watching this because a year ago I had the same look to my bearings but under different circumstaces. My engine lasted about 10,000 miles and I was having an oil control issue from what I can tell. I play canyon carver with my TA and I was collapsing my lifters during hard cornering. The engine is ready to go back together and I'm VERY nervous about the breakin. It's terrable what happened to your engine but it's sure nice you posted and the site is here because we can all get a heads up from your experience.

Thanks for posting this,

[TnVTX]

Originally Posted by guidos

Just a thought, I wonder how much of the metal from the last motor failure was still in the lifters. Somebody mentioned it to me once and I was wondering what others think. I never really thought of it but I guess if there was metal in the oil the lifter would see some of it.
Thoughts?

I had the same concern & was about to order the same cam & lifters new again. The engine shop told me that would just be a waste of money, as the lifter's oil hole was so small, only tiny particles could have made it in, and, since I was converting to non-bypass oil filter housing, those particles would get caught in the filter before getting fed to the bearings.

[TnVTX]

Originally Posted by uneasyrider

Good to know about the Royal!

I'm watching this because a year ago I had the same look to my bearings but under different circumstaces. My engine lasted about 10,000 miles and I was having an oil control issue from what I can tell. I play canyon carver with my TA and I was collapsing my lifters during hard cornering. The engine is ready to go back together and I'm VERY nervous about the breakin. It's terrable what happened to your engine but it's sure nice you posted and the site is here because we can all get a heads up from your experience.

Thanks for posting this,

Please be sure to keep us posted on how your engine does with the new rebuild.
For the time being, I've found a 455, and I think I'm going to put my heads & cam in it and just run it for now. I will hopefully someday find the culprit of my stroker's failure, fix it, and get it back up & running again.

[uneasyrider]

Originally Posted by TnVTX

Please be sure to keep us posted on how your engine does with the new rebuild.
For the time being, I've found a 455, and I think I'm going to put my heads & cam in it and just run it for now. I will hopefully someday find the culprit of my stroker's failure, fix it, and get it back up & running again.

I'll let everyone know but I sure hope the only thing I have to say is it went perfect.

To tell you the truth I've been thinking about this thing and I'm a little suspect of the simple fact both engines are stroked. I know there are plenty of people that haven't had problem with strokers but side loading might become an issue on these engines and if all isn't perfect the extra load doesn't help anything that's for sure. I'm thinking of running a stock stroke crank and rods in my engine in the future. I've messed with it on the dyno sim and the torque drops off but the hp doesn't take to big a drop and in some cases goes up but peaks at a higher rpm. Just my thoughts.

[Will]

Provided some of the other problems mentioned here - bearing halves being installed top vs. bottom, and what's up with the cam bearings??? - I'm still thinking it's a bad finish on the crankshaft. The poster from Sealed Power down at the machine shop I'm trying out right now agrees with this assessment.

Has pictures of bearings with various kinds of damage and the causes of that damage. Has a pic of bearings that look just like yours - all shiny and looking like they've been polished with a well used scotchbrite pad. The cause listed is "poor crankshaft finish."

Good luck!

[Jack Gifford]

Originally Posted by TnVTX

... those particles would get caught in the filter before getting fed to the bearings.

Not all of them. Say you use a 25 micron filter element- probably all particles smaller than 25 microns will pass through- and, by definition, the filter will only trap a certain percentage of those larger than 25 microns. I don't remember typical percentages- maybe 90%? That's still 10% of the debris from all sixteen lifters could be pumped through the engine. Why not just start 'clean'- any lifters can be disassembled and thoroughly cleaned and reassembled.
Incidentally, there are no "tiny" oil holes in lifters- the smallest oil passage in a lifter is many times the size of typical bearing clearances.

Edit: My bad for saying "any lifters can be disassembled..."- I forgot about roller lifters with permanent tie-bar attachments.

[TnVTX]

I'm wondering is it possible for the Eagle cast crank to have poor metalurgy, and is allowing the crank to flex around when under a hard load, and this in turn beat the bearings out?

[uneasyrider]

Just breaking it down,

1. No blueing on the bearing so plenty of oil?
2. Water temp was normal during the run so not a cooling system issue?
3. No detination?
4. No over rev?
5. No lugging the engine down?

If all the above didn't happen it must be a clearance issue of one kind or another. I would think if it was too tight it would have heated the bearings and too loose might have caused what happend. It could be the rods, crank or mains were "egg shaped" but I would think it would show hot spots?

I don't know but it seems like it was too loose to me.

[TnVTX]

Originally Posted by uneasyrider

Just breaking it down,

1. No blueing on the bearing so plenty of oil?
2. Water temp was normal during the run so not a cooling system issue?
3. No detination?
4. No over rev?
5. No lugging the engine down?

If all the above didn't happen it must be a clearance issue of one kind or another. I would think if it was too tight it would have heated the bearings and too loose might have caused what happend. It could be the rods, crank or mains were "egg shaped" but I would think it would show hot spots?

I don't know but it seems like it was too loose to me.

For these H series bearings in a high perf motor, the standard clearance is
.001" per inch of journal size. I found the build sheet from the engine shop where the rods were set at .0025 & mains @ .003.
With this crank having big block chevy long rods in it, the crank has 2.2" rod journals, and 3" mains. So, the clearances they put it at are on the money for this setup. (I used plasti-gauge upon tear down, that would probably explain the false tight readings from me compressing the plastigauge especially on the rods, where they were moving around during tighening of the bolts & loosening them back...
For these bearings to have wiped out this severely in just 100 miles, I don't think just a couple of thousands clearances could have caused this jmuch damage. Especially since I didn't "stomp it" until the 90 mile mark, which I shifted at 5,200 rpm...

I'm still wondering about the crank's integerity...

[johnta1]

Who polished the crank the first time?

Who ground the crank the second time?

Might try reading the PDF at this link.

Bearing Failures

[Will]

Thank you johnta1!

Sometimes it's like being a voice in the wilderness around here.

[TnVTX]

Originally Posted by johnta1

Who polished the crank the first time?

Who ground the crank the second time?

Might try reading the PDF at this link.

Bearing Failures

Top Gun Racing Engines is the shop who did the polishing of the crank. He told me he polished it the same way he does all his race engines, paying attention to direction of rotation. He swears up & down it was polished correctly, both times. (He builds alot of round track engines, IHRA & NHRA engines). He also knew this was a street car, so longivity was of most importance to me.
Now, how good of a job he did for me will have to be proven or dissproven...
{I've got find a way to measure the RA}
I asked him . who he used to grind the crank for the second time up, and he said he didn't remember which crank shop he used, as he trusts (2) different shops depending on their backlog.
I agree that the first time the motor wipedout the bearing shells, there didn't appear to be much heat, however, I didn't take the time to really get detailed pics before I took it back to him.
This time, I took my time taking pics during dissassembly, and there is some evidence of heat present, the rod crank journals are darkened, & a few of the bearing shell's backside are darkened as well.

I'm taking this mess to an older, area Pontiac racer/builder (Bod Crawford), and let him try to find the cause of the failure. He, like the most of the rest of us, is suspecting the crank is at fault.
(But, I want proof, not speculation of the true cause).
He doesn't "trust" any of the crank grinders close to us, he takes all his cranks to Red Cornett Racing, along with his personal mics, for any crank (or block) work.

Thanks for the link!

[Cliff R]

"I'm wondering is it possible for the Eagle cast crank to have poor metalurgy, and is allowing the crank to flex around when under a hard load, and this in turn beat the bearings out?"

I've seen this happen to two customers of mine, using Butler "stroker" 400 engine kits. One of the engines was built by Butler. They were fixed by replacing them with cut down factory "N" cranks.

FWIW, I would scrap the cast steel crank, and obtain one of the new forgings or a factory "N" crank.........Cliff

[uneasyrider]

Originally Posted by Cliff R

"I'm wondering is it possible for the Eagle cast crank to have poor metalurgy, and is allowing the crank to flex around when under a hard load, and this in turn beat the bearings out?"

I've seen this happen to two customers of mine, using Butler "stroker" 400 engine kits. One of the engines was built by Butler. They were fixed by replacing them with cut down factory "N" cranks.

FWIW, I would scrap the cast steel crank, and obtain one of the new forgings or a factory "N" crank.........Cliff

I sure hope that ISN'T the case or when my engine gets back on the road I might be looking at the same thing. I didn't get a chance to go look at my bearings after they pulled it apart but it sounded like it was the same as above. The thing is my engine lasted about 10,000 miles AND I had a bad enough oil control problem that the lifters lost oil under hard cornering and it sounded like a sewing machine under the hood. I am fairly sure that that was THE issue but this and a couple other posts have me a little nervous. I can say one thing I WILL use diesel formulated oil in it next go round AND some EOS.