Possible to have a bad bearing, and also good oil pressure?

[padam]

Is it possible to have a bad bearing, and also good oil pressure?

I had some stuff happen that made me think the that I might have a bad bearing.

The motor is a 64 413, .030 over, 10:1 compression, (906 Heads milled .090).

Engine was rebuilt in 1985, and has been raced and driven since, probably not more that 20k miles. but when I raced I ran it pretty hard, usually shifting at 5800 (4 speed).

After a 20 year layoff, I took it to the track a couple of times this year. It wasn't running very good, so I have been fixing a bunch of stuff, and trying to get it back in tune. Again, running it pretty hard.

I did a lot of testing and can't really find anything mechanically wrong YET.

I used to always run Valvoline 20W-50 racing oil, but I couldn't find any so this summer I put in Delvac 15W-40. Oil pressure is normally 70-80 psi and around 50-60 psi at idle.
after a couple of trips to the track, oil pressure at idle was dropping to 30-40 when hot

It seemed like I was getting a LOT of smoke out of the breathers.

I changed the oil to Castrol 20w-50, and my oil pressure cold at 900 rpm is 75 psi, quickly increases to 80. Ambient temperature is 85.
No smoke out of the breathers, but I only ran it briefly.

I plan on tearing down the engine this winter, but would really like to race a couple more times this year if possible.

What do you guys think?

 

[Tony Tee]

In the late 70's the 440 in my charger was slowly increasing it's oil pressure. And found out why after taredown. Rebuilt the engine due to a imbalance. Bad vibration. The timing chain sprocket teeth had a nylon plastic covering that was disintegrating and small pieces were embedded in all the bearings building up the surface . Had great oil pressure. I don't know how the plastic got passed the oil filter? But I used to use Fram oil filters. I'm glad I rebuilt the engine when I did. So maybe you have something coming apart in you engine?

 

[padam]

I cut aprt the filter, and there are some small fragments in there.

 

[68Moparmaniac]

Frag's in the filter means your on borrowed time brother...
If it we're mine, I would open her up and see what's up before you scrap a crank/rods/block.. etc. unless you don't care about it and have another bullet ready to go. A big block grenading in front of you wouldn't be a pretty sight especially when your doing 90 knots down range... seems to piss off the track crew too for some odd reason

 

[padam]

Frag's in the filter means your on borrowed time brother...
If it we're mine, I would open her up and see what's up before you scrap a crank/rods/block.. etc. unless you don't care about it and have another bullet ready to go. IMO

That's what my head is telling me too.
My heart says that summers almost gone, and I REALLY want to go racing.

I would like to build a stroker, so a 413 short block wouldn't do much for me. Not in the budget til next year though.

On the other hand, I could rebuild this engine without it costing me too much and stay at the same performance level, and at least still race it.

 

[dvw]

What was in the filter? If you've ever cut a filter you'll know there's always something in there. Was it shiny brass flakes? Breather smoke would not necessarily indicate bearing failure. Unless it was so far gone it was severely oiling the cylinder. If that was the case, it would be knocking. Pressure is resistance to flow. Thinner oil equals less pressure. 30-40 @idle. My bet is there is no bearing issue.
Doug

 

[Nate S]

Blowby and bad bearings are two entirely different things. No clicks taps or knocks? You're probably ok. Let's hear about those flakes though.

 

[padam]

I haven't cut many filters apart, so not sure what I am supposed to see.
I will take another look later, but just a few silver metal flakes .02x.05. some smaller specs.

 

[padam]

My header gaskets were leaking really bad making a clacking noise. When I was at the track the starter said he thought I had a rod knocking, but I fgured it was just the exhaust leaks.

I replaced them with Taylor cable gaskets, but they are still leaking some, so it is still hard to hear.
Last time I ran it I thought I was hearing a slight knock.
So I pulled the valve covers, checked that all the pushrods were where they wer supposed to be, valve springs all look good.

Compression test, all 150-165 psi.

I went all over the engine with a stethoscope and didn't hear anything like a knock.

 

[padam]

The engine has developed a mis-fire at wide open throttle. Fuel pressure was dropping off, so I thought it was going lean.

Is it possible that it would run so rich that it is washing the oil off the cylinder walls?

I can't remeber if a blown power valve will cause a rich or lean condition.

 

[PRND21]

Engine sitting idle for 20 years can cause rings to loose some tension causing more blow by. Also will cause deterioration of fuel and ignition systems.
Send a sample of your oil out to be analyzed, that will tell you what shape your internals are in.

 

[steve340]

I have seen old bearing shells delaminate (my description). If it has been a good engine why push the point and risk killing it.
My opinion.

 

[747mopar]

Any oil volume that the pump creates beyond what loss you have at the bearings, rockers, etc creates psi so yes it's possible, it just means your pump is still capable of supplying more than enough volume.

 

[WP29440SE]

if it's eating its self up, it will show up in the oil regardless of the filter as a metallic sheen when stirred up. a rod bearing will start to make racket at around 2,000 rpm and may sound like a lifter or header leak before getting worse. your hot idle oil pressure will gradually get lower.

 

[padam]

Well, at least if I do go to the track, I won't have to drive it there. That probably causes more wear than a few 1/8 mile runs.

I bought a brand new used trailer last night.

 

[padam]

I took it out to Magnolia drag strip yesterday.

It seemed to run fine.
I made 4 1/8 mile passes. 8.80 was the best but I was off the gas on that one.
The engine ran fine. No unusual noises. No excessive smoke. The oil pressure held at around 70 psi at idle. 80 off idle.

I upped the fuel pressure from 6 to 7.5, and that seemed to cure the mis-fire.

In conclusion, I may run it a couple more times this year, then tear it down this winter.

 

[RJRENTON]

Many years ago, my brother was stop lite racing (Luxury Car Eliminations) the old man's 1965 Chrysler Imperial LeBaron, against a similar year Lincoln or Cadillac. The Imp was a 413/ 340 hp with a 727B TF and 2.94 rear. During the contest, my brother over revved the 413 to ???? RPMs (no tach just feeling), resulting in spinning # 5 rod bearing. Upon teardown at the local Chrysler dealer revealed the following: the big end of #5 rod was blue due to the heat generated, but still intact, the bearing shells were welded to the crank journal, requiring a chisel to remove them, the crank journal was also heavily scored, the rest of the bearings looked OK. There was NO LOSS of oil pressure or engine overheating noted. My brother drove the car home, approximately 4 miles, then parked it. I heard it run the next day...sounded like WW-3...much knocking and banging but with good oil pressure, on the dash instrument. The car was flat bedded to the dealer. The fix, under Mopar's 5 yr/50,000 mile warranty (labor + materials) was to install a short block assembly at no cost. We had been using a 10W-40 hd oil...Quaker State changed every 3000 miles.
Upon further review, it was decided that because the bearing shell welded itself to the crank, blocking the crank's oil feed hole, was the reason oil pressure was maintained. The bearing shell was rotating, rather than being held stationary, in the big end of the rod, lubricated only by splash, which caused the blue appearance.....we were lucky that rod did not snap off and grenade the engine....somewhat of a testimonial to the ruggedness of the 413 engine......then came the inquisition by the 'Old Man.....WHAT WERE YOU DOING AND HOW DID THIS HAPPEN.....but that's another story for another time.....
Just thought you might like to know.....
BOB RENTON

 

[padam]

Many years ago, my brother was stop lite racing (Luxury Car Eliminations) the old man's 1965 Chrysler Imperial LeBaron, against a similar year Lincoln or Cadillac. The Imp was a 413/ 340 hp with a 727B TF and 2.94 rear. During the contest, my brother over revved the 413 to ???? RPMs (no tach just feeling), resulting in spinning # 5 rod bearing. Upon teardown at the local Chrysler dealer revealed the following: the big end of #5 rod was blue due to the heat generated, but still intact, the bearing shells were welded to the crank journal, requiring a chisel to remove them, the crank journal was also heavily scored, the rest of the bearings looked OK. There was NO LOSS of oil pressure or engine overheating noted. My brother drove the car home, approximately 4 miles, then parked it. I heard it run the next day...sounded like WW-3...much knocking and banging but with good oil pressure, on the dash instrument. The car was flat bedded to the dealer. The fix, under Mopar's 5 yr/50,000 mile warranty (labor + materials) was to install a short block assembly at no cost. We had been using a 10W-40 hd oil...Quaker State changed every 3000 miles.
Upon further review, it was decided that because the bearing shell welded itself to the crank, blocking the crank's oil feed hole, was the reason oil pressure was maintained. The bearing shell was rotating, rather than being held stationary, in the big end of the rod, lubricated only by splash, which caused the blue appearance.....we were lucky that rod did not snap off and grenade the engine....somewhat of a testimonial to the ruggedness of the 413 engine......then came the inquisition by the 'Old Man.....WHAT WERE YOU DOING AND HOW DID THIS HAPPEN.....but that's another story for another time.....
Just thought you might like to know.....
BOB RENTON

That's a good example of how it can happen.
The only other engine l saw for sure with a spun rod bearing was a 318 poly, and it was knocking, overheating, no oil pressure. I don't remember the tear down details, but those were the signs I was looking for.

I'm just going to figure the 413 is tired and needs a rebuild.

Thanks for the reply!

 

[dvw]

I spun a bearing in my 68 Road Runner as a kid. Noticed it dropped about 10-15lbs of oil pressure. Didnt know what happened but it had a noise. Drive it home 40 miles from the track. Pulled it apart. Crank wasnt damaged. Ordered up a new rod from the dealer. Didnt ever think about a used or resized rod. Figured since it was a 6 pac it must be a 6 pac motor. When I received the rod it was thicker. Put it in anyway and drove it for 3 years before rebuilding it and swapping in a normal LY rod. My 1st engine experience back in the day.
Doug

 

[747mopar]

I took it out to Magnolia drag strip yesterday.

It seemed to run fine.
I made 4 1/8 mile passes. 8.80 was the best but I was off the gas on that one.
The engine ran fine. No unusual noises. No excessive smoke. The oil pressure held at around 70 psi at idle. 80 off idle.

I upped the fuel pressure from 6 to 7.5, and that seemed to cure the mis-fire.

In conclusion, I may run it a couple more times this year, then tear it down this winter.

Magnolia, must be close to me if your referring to the Ohio track?