WallyP

Have you checked the end play on the crank? At this point, that would be something that I would do...

Garth S

That would be two votes for checking the crank .....

geekapalooza

Just to clarify, I'm using the Kempf Tool.

Also should I consider the tensioner arm itself?? It did take a little prying to get it removed originally.

Wally, Gretch, Jim, Garth, Bill, Dave, Anybody...... How should I go about checking the crankshaft items being referred to?

Sounds like we may be starting down the right track (fingers crossed again).

Garth S

Read this thread first ... http://members.rennlist.com/v1uhoh/cranksha.htm ....

Hopefully, you have done all of this, and this is NOT an issue - but is why ease of turning the crank when the moaning starts was mentioned: No doubt, Wally is thinking the same thing: There is a current thread on this page re 'level flex plate' by bgrabner .....

As far as the tensioner arm bushings, if you can move it back and forth by hand, it is fine. ( I had some bushings machined from Nylatron for one car this summer - to a tighter tolerance than oem bushings: they are working fine, although somewhat tighter to 'rock' than OEM ones).

Quote: "Sounds like we may be starting down the right track (fingers crossed again)." - ah, ... no. - keep your fingers crossed that this is not the right path - unless it is very early in the game.

geekapalooza

Just thinking out loud here, but why would this pop up the same time as a TB job? Could the car parked on ramps (front tires) be the differentiating factor???

And no, I have never made this check, but it just happened to be the next item on the list for the car.

If this is the culprit, would 10 minutes of idling be over the limit, since the noise just started?

geekapalooza

Ok - you guys have succeeded in scaring the cr@p outta me at this point

Another question:
Since we know for a fact the T-Belt is getting too hot, how would the thrust bearing (God forbid) issue correlate with the T-Belt heating up? Curious minds want to know.

goliver

I feel for you Rob. Not sure where Garth and Wally are headed but since all else has turned up nothing it can't hurt. Just can't in my feable brain see how they could be connected. If it was fine before the belt change what is different now? Hope it all turns out okay. You have some moral support at least.

Regards,

Gretch

If the timing belt is off, measure the end play of the crank while pushing it in and pulling it out of the block. There should be "some" (check the Nichols site for the specs) end play, like 20/thousandths..... If there is none, then you have a "rhut rho" moment. In that case go to the "check flex plate tension" section of the nichols site.

What I read WallyP as saying is, the heat that is melting your belt is coming from somewhere......if you have eliminated everything else it touches, except the crank, then look for malfunction symptoms that would cause the crank to get over heated.

Personally I think it is a long shot, because the TBearing is in the middle of the block, and the friction needed to ruin it would prolly not translate to enough heat at the end of the crank such that the belt would be cooked.......But you never know, and checking this out will take only a few minutes.......

Has the car ever had transmission, torque tube or torque converter work done to it?

Bill51sdr

Um, I may be wrong here, but I seem to recall the 'hot spot' causing the problem was the WP pulley. Do you still think you have a heat problem? Also, please, if you can, describe the moaning sound you are hearing. As I said in an earlier post, you may be concerned with a noise that is perfectly normal after a new TB installation.

geekapalooza

I did notice the RPM's drop a tad as the moaning sets in. Sounds like a possible thrust bearing related symptom . Garth mentioned engines have been known to completely stall from the Thrust Bearing Issue.

Bill S. - The moaning is way too noticeable / loud to be a normal rubber belt breaking in. And what are the odds of 2 bad WP's - back to back? I did also notice the moaning sounding louder when laying under the engine, than from atop.

The tranny was apparently dropped in 1995 (no receipt for this, but a date of 07/1995 is inscribed on the pan). That and the combination of the flexplate never apparently having been adjusted, and almost 50k miles, makes it sound like a strong possibility.

Let's play it safe - I'll plan on dropping the belhousing tomorrow night, if time allows. Then subsequent to that, plan on using the laser thermometer on the TB pulleys, and checking crank end-play on the front side too this weekend.

Ok - I have to ask - If there was rubbing by the crank on the block for a whole 10 minutes of idling, I'm wondering if the engine is toast - or saveable after the pinch collar is adjusted? Any historical data to glean from others with experience / info in this area?

Garth S

Quote: "Ok - I have to ask - If there was rubbing by the crank on the block for a whole 10 minutes of idling, I'm wondering if the engine is toast - or saveable after the pinch collar is adjusted? Any historical data to glean from others with experience / info in this area?"

With fingers crossed, all you are doing at this point is good preventative maintenance. Measure the distance from the ring edge of the machined taper on the shaft to the edge of the collar clamped to the splines. Release the 8mm hex pinch bolt, and if the flexplate moves rearward, remeasure.( my S4, with only 50KKm/30K miles, released 3.15mm - which caught my attention. Fortunately, crank end play was ~ o.006-7") Before reclamping the collar, you now slide the crank each way to allow a measure of end float. Capt'n Earls notes ( and others) have the specs, but IIRC, 0.006" - 0.016" is a good range. If float is 30 - 40 thou, measure twice ....
If for no better reason, due to the confounding complexity of the moaning & 'melting' TBs, this is another variable to check - and hopefully eliminate.

Old & New

Rob,

It is unlikely that you have a TBearing issue; what Gretch said.

You should be able to find the source of the heat pretty quickly with the IR thermometer... did you get anywhere with it?

Did you double check the belt path tho make sure no foreign objects were lodged in there, nothing is out of place, rubbing the belt, etc?

geekapalooza

Old and New Wrote:
Hope you're right. I have been meaning to do this check anyway, and definitely want to rule this out.

I'll also use the Laser Thermometer this weekend on all the T-Belt pulleys. The belt tracks straight and true after the bad WP was replaced, yet the belt is still getting too hot. I now have a neat new collection of barely used T-Belts!

Old and New Wrote:
Definitely. No rubbing, chafing of belt on the sides, etc. Just the Heating of the belt. I guess 2 bad WP's in a row are possible, but the odds boggle the mind.

Bill51sdr

Rob,

You did not have this noise prior to the TB/WP change, true?? I seriously doubt you have a thrust bearing issue. The noise is related to the work you have done. An overtensioned belt WILL make a lot of noise, and is more prevalent near idle, but I do know you mentioned you have been careful about that. I would just concentrate your work on what you have done and not go off on tangents for now. Good luck!

geekapalooza

Ok - I’m going to throw out a really far-fetched hypothetical here… Please try to refrain from laughing out too loudly.

First off – a disclaimer. I’m 99.99 % sure I DID NOT do this. But you know, have you ever walked out of your home, and wondered “did I lock the door”, or “did I turn off the coffee maker”, or “did I hit the button and close the garage door”.

That’s where I’m going here…

Let’s just say, a certain DIY 928 guy were to ACCIDENTALLY leave paper towels in the 3 coolant passages that open-up behind where the water pump mounts to the block. That is, he would plug up the holes while the old WP was off the car for a day or two, then when he went back and installed the new WP, he would forget to remove the paper towels.

Also, lets just say that certain 928 DIY guy dropped one of those paper towels (Brawny) in a bucket of coolant to see if it would fall apart like toilet paper. Tests revealed the paper towel stayed intact.

Ok – I know what you’re thinking, but like I said, I’m 99.99% sure even I didn’t do such a braindead thing. Mistakes happen, but I cannot imagine it in my wildest imagination that this occurred. If I did, I’ll wear a dunce hat at Sharktoberfest, or buy a round of beverages for all, or something to redeem myself (sense of humor still intact at least).

If paper towel sections were in there, would they cause undue pressure on the water pump, causing failure and heating up of WP pulley? When I replaced the new – bad 1st WP, I checked the drained coolant, WP impeller, and block passages (visible parts) for any signs of paper. NONE whatsoever. Also the temp gauge shows normal readings.

Guess I’m grasping at straws here.

Let the flames / laughs / jokes / whatever begin…