348 engine problem need the 348 guru's

There's so much to address here!

First, did you see a drop in the oil pressure gauge reading, or get an oil pressure warning light when the initial problem occured? If it really "spun a bearing" you should have seen something, and heard "knockknockknockknock". I wouldn't think the engine could starve for oil if it really had 8 quarts in it, and the fact that no oil was showing on the dipstick is immaterial if it wasn't checked with the proper procedure (engine warm, just shut off). Starvation from going through a turn??? On a dry sump engine?

Did you see the old bearing (the one that "spun")?

They replaced all of the crank bearings? Oversize? Standard?

They didn't pull the cams to check the cam journals?

Did you have normal oil pressure readings before your latest problem?

Based on what you have described, this sounds kinda funky.

 

It all sounds wrong. I haven't even heard of someone doing a bottom-end rebuild without at least checking the top end!



It's generally cheaper to part out and/or sell whole your broken 348 motor (and simply buy a working one already intact) than to pay to have someone rebuild her.


But that being said, you need proper diagnosis first.

 

Was the chain driving the oil pump ever replaced in the car? Some of the cars had a problem with this-I think it was a warranty repair. I have a motor if you need one.

 

Well,

You could ship the whole car to Plugzit or me and the three stooges will put Bruce's rebuilt motor in and test it then ship it back or you come to Cali to drive it back. It really isn't that hard but you may need to pay bruce for the motor, leave the core, plus a bit for Bruce's labor and to feed the Stooges which could cost more than Bruce's labor. Other than that we work for free. How's that for a deal?

 

That sounds like a great idea FBB! I wish I was there to wrench with you guys!!

 

I will volunteer my labor for a "breakfast at Joes" !!

Yeah.............. Pap you should be hanging with the bro's !!!

 

Hey pap you are always welcome to join us. The more guys we have the quicker the job gets done. How about a So Cal vacation? Anyway, I don't think you can find a better bunch of 348 mechanics than the stooges. How could anyone go wrong? I'll voluteer my garage, lift and tools. I bet we can have the engine in and out in a weekend easy. Shoot...I'm so confident that if CTM stays at the seasprite motel right on the beach he can come help too and drive the car home on Sunday!

 

Sh*t yeah man! Many hands make light work. You bet your ass you guys could get the job done in a weekend!! I am coming over to LA in September and I will catch up with you stooges for a beer or 10!!

 

I'd drive mine down for the weekend and contribute free labor. Would like to meet the stooges one of these days.

 

OK guys, what's your opinion? Is there ANY possibility that you could spin a rod bearing without hearing it knock? Is there ANY possibility that you could spin a rod bearing without a major, significant drop in the oil pressure reading?

I am confused by your wording, CTM. I asked if you saw the old bearing - you responded that "it was shown to me along with the journal. It was burnt and the journal was broken". The journal is the polished part of the crankshaft that the bearing rides upon. By the journal, do you mean the cap for the connecting rod? If the bearing spun, it almost certainly wasted the connecting rod and its cap. You MIGHT be able to polish a light score off the journal (very, very edgy), but there ain't no way you're going to replace a connecting rod from below - it's attached to the piston. Impossible.

I'm still confused as well by your description of "a little skip" and "a loss of power". These aren't really symptoms of a problem with a bottom end bearing. Something fishy about this deal.

 

Great idea. I wish my trip to the meet the stooges was as short as yours!

 

Hard to say man. Usually big ends knock LOUD, but you never know in this case. Maybe he couldnt hear it?? Anything is possible I suppose.

 

There you got it CTM Free labor from the brotherhood! PAP CTM has waited a year September would be just fine by me. Matertech you are welcome too. How could CTM pass up this deal?

Anyway CTM does not sound to engine savy but he would need to start at basic diagnostics like leakdown, pull valve covers for minimal topend inspection and maybe drop the sump pan. If he could do that he could change the motor himself. So unless a brother could go over and see him to get more info I think the problem sounds like it stmes from the original problem as in never being really fixed. We need more details:

1) does it start?
2)does it idle? idle quality
3) does it rev? rev quality
4) does it drive? Where is power loss, offline, mid range, hi rpm?
5) strange noises under any of these conditions?
6) do all guages read normal? oil pressure specifically

Well thats a start.

 

Sounds like a plan FBB!!

 

Well, that tells me that they replaced the big end bearings and cleaned the oil tank and cooler as best they possibly could. They could not remove scor mark from crank and recommended crank machine ect.....ect......
They obviously didnt find the cause of this spun bearing and it has happenend again mate. It could have a partially blocked oil gallery to those rod bearings, causing this failure. If you put new bearings in it again, it will probably do the same thing. I think its time to remove engine and pull apart to find out whats going in there man.

 

Forget the friggin' engine. This is a great movie script. Does John Cusack look like you?

 

Hmm, I wonder if you broke a valve spring or threw a shim or two. The crack you hear and the spun bearing might have resulted from valve impact on piston (or more). It sounds as though there may be an oiling issue, as if there's a circulation problem occuring intermittantly. I had a Vette do this once. It ran fine then didn't. It clunked, but it was upper end not lower. It was hard to tell where the noice came from, however.

Now, I wonder what you are not telling us. When did you or someone else over-rev the motor? Was it an errant downshift? P

I'm in for the cross country diagnotic and repair BTW. Let me know guys and I'll bring beer. FBB's house is better due to his unbelievable equipment.

 

If the car makes it to LA for rehab I'll lend a hand as well. Gotta do something with my time.... I might even learn something!

 

There are several things here that don't make sense to me. But for now...

I wonder if there could be a restriction in the oil flow to the pressure pump in the sump. In a case like that, perhaps you could have good PRESSURE (at least off and on) but low VOLUME.

Has anyone looked at the condition of the flexible oil hose from the sump tank to the engine? I wonder if it's possible that this hose is kinked, or has an internal breakdown that keeps the pump from drawing the oil back into the engine at full flow rate.

I simply don't understand how, if the engine had TWO faulty rod bearings on the front crankpin, it could still be reported that the engine had good oil pressure readings.

 

Thats why you gotta love the 348 Brotherhood!!
Count me in too, if this happens when Im there.