Spun bearing?

[RI-SHO]

Is there anyway to listen for a spun bearing or diagnose it without dropping the oil pan? Could this cause the car to crank with spark/fuel and still not start? I am also getting a loud popping from the air filter, sounds like it backfiring and ocassionaly there is a big puff of white smoke when it pops from the filter.

Or after all that the car should still start but just idle like crap and have no power?

Mechanic has yet to figure out what it is, he said he will run a compression test today, hope its good news.

 

[Mike Kopstain]

It sounds like your timing belt has jumped... Check the timing with a light.

 

[pete c]

RI,

First off, let's describe "spun". A bearing can be scored and therefore bad but not yet spun. A spun bearing is one that has actually shifted position in the journal. When this happens to a rod bearing you will definitely have a bad knocking sound. But it has nothing to do with fuel/air delivery, timing or compression. In otherwords an engine with a bad bearing should run perfectly until the bearing problem gets so bad that either the engine seizes or you snap a rod. This WOULD have an effect on the all important fuel/air/timing/comp equation. So once you get the other problems worked out and actually get it running you can then determine whether or not you have bearing trouble.

BTW, if your mechanic thinks that he can't get it running because of a spun bearing, but, the engine does infact turnover smoothly (all the pistons are going up and down), I recommend you push, pull or tow that bitch to somebody who has a clue, immediately.

 

[Yamaha V6]

I recommend you push, pull or tow that bitch to somebody who has a clue, immediately

Now THAT'S funny Pete.

 

[RI-SHO]

Lol he wasnt the one tha brought that up, it was Erik so I just wanted to get all of your opinion on this problem. I really have no other choice b/c I had to push the SHO with a bud to his shop about a 1/2mile of uneven road. He was the same mech which diagnosed my 2bad fuel injecotrs last year and faulty ECU which was replaced.

Just now its a PITA trying to figure why it wont start he probaly his ideas but i'm lost considering everything that was replaced check and checked again.

Is the timing able to be checked with the engine not being able to run/idle? And how a timing belt just jump? Is it just a rare occurence?

 

[BeatDaSHO]

the tensioner for the belt might be bad therefore creating just a little slack and boom; jumps a tooth.

Greg

 

[Mike Kopstain]

Oh shit man... I had a blonde moment when I wrote to check the timing! It can't be checked with a light if the engine won't run. You will have to remove the cover's and visually inspect the belt.

 

[pete c]

just cause it ain't running, doesn't mean it ain't firing. I would put the timing light on it anyway and take a look. You should be able to tell if it's atleast close, in which case, it should run.

 

[pete c]

hey RI, looks like you oughta modify your car info, how's this.....

Click to see my modified MTX 93 POSHO 15.3 [email protected] (with a few buddies pushing it). But I did get it down to 1:15.3@ 33mph on the hook behind a '98 ford Powerstroke 1 ton wrecker. thumbs_u

 

[sdpatt]

With the little bit of information provided, you might want to run the EEC KOEO test and look for a CID sensor error code.

Has the engine been run since this happened?

 

[billh]

One way to check for bearing damage would be to remove the oil filter. Very carefully cut the top off of it with a set of tin snips. Remove the paper cartridge from inside and cut the ends off. Next, spread out the paper and look at the outside. Bearing damage will show up as a lot of copper material in the paper. A spun bearing will just about pack the filter full of bearing material. You could use a hack saw to cut the top off of the filter, I never did because the shavings from the blade got into the filter and I never could tell if I was looking at engine damage or hack saw shavings.
We used to do this on a regular basis on our Super Stock engines and managed to find some problems before they cause an engine explosion.
Good Luck
Bill

 

[shojuan]

Hey, that's a great tip Bill! I'm going to try that right now with my truck's oil filter I just replaced. May as well do it with my SHO's old one I haven't thrown away just to get a baseline.

Thanks

Rick

 

[RI-SHO]

sdpatt:
With the little bit of information provided, you might want to run the EEC KOEO test and look for a CID sensor error code.

Has the engine been run since this happened?

I ran the codes paper clip style and put his code scanner with no codes at all. So far plugs, plug wires, coilpack, DIS module, fuel filter, CPS, crank sensor, and tried MAF from another SHO. Still it just cranks and gurgles below 200RPM's with the tach jumping up every few seconds when cranking, I basically gave up b/c I was just draining my battery at this point. Should I tell him to check the altnator also which I believe would cause the car not to start.

Do you guys think now the engine is flooded with fuel if I am getting the loud popping from intake and sometimes the intake manifold itself? Anyways this weekend he will be checking the timing reffering to the big azz book of SHO specs I gave him, hopefully it turns out to be that so I can stop playing mickey mouse games with this damn car and actually be driving it.

 

[GaryH]

now that definately sounds like the teeth on the timing belt got sheared off and jumped time... i would take the timing covers off and crank the car manually to check the teeth. then reline up the marks on the sprockets. good luck

 

[billh]

shojuan:
Hey, that's a great tip Bill! I'm going to try that right now with my truck's oil filter I just replaced. May as well do it with my SHO's old one I haven't thrown away just to get a baseline.

Thanks

Rick

Rick
The only drawback to doing this is it's REAL MESSY! and you have to be careful not to cut yourself on the sharp edges of the filter. I never did figure out a way to hold the damn thing while cutting on it, and with all of the oil leaking out it was easy for the filter to slip. One guy I know used to put the filter in a vise and use one of those chain type tail pipe cutters. Said that worked fine but I never got around to trying it
Good Luck
Bill

 

[pete c]

If you have one, use a dremel with a cutting blade. Makes a nice clean cut through just about anything. Just don't go any deeper than necessary or you will snag/break many cutting discs.