Ruh roh (me too)

[sportsroof69 13]

Well, in the spirit of broken stroker motor threads, I figured I'd share my headaches.

 

As many may know, I swapped the toploader out this winter for a PA Supercomp C4, Neal Chance converter, pro transbrake, and all that good stuff. The day I got it finished up, was the opening day for the local track, so I drove it around a little bit for some shakedown, and then put the slicks on and loaded it up.

 

Off the trailer, it went its fastest pass ever, and that's even after taking some gear out. We made about a 3/4 pass on the nitrous and had a problem, so I let out. Turns out that the distributor has 5 bolts holding the head to the shaft that had came loose, so it rolled about 5* of timing and torched my head gasket. It was just a freak accident I guess. Just some bad luck.

 

 

I got that fixed the next day, and drove the car all week. Everything seemed fine. It was running real well, and with that big stall, it still has great street manners. I had an appointment in Norman, which is about 80 miles from where I live, so I decided to take her out for a little road trip. I did what I had to do, and stopped by a friends house on the way back. I was talking about how the new transmission is leaking, so he said pull it in and lets put it on the lift to see if we can find it. When I pulled in, it was making a noise. I don't know how to describe it really. It was just a squeaking noise.

 

We were looking for the noise, and couldn't figure it out. Finally I noticed that it looked like the flexplate, was against the block plate, so I grabbed a pry bar. When I pried the flexplate back, I had a terrible sinking feeling as it moved probably 1/8". I went up to the balancer and pried it the other direction,and sure enough.........lots of end play. I mean a LOT of end play. My thrust bearings are absolutely gone. The noise was the flexplate actually rubbing the block plate.

 

After tearing the engine down a few days later, I'm convinced that if I would have drove the remaining 60 miles home, the engine wouldn't have made it. The thrust bearings were gone to the point that the crankshaft had actually rubbed the main caps. I can't believe it hadn't self destructed. So, now the engine sits in pieces, because it ruined the crank and I need a new one. I'm tapped after all the money I spent over the winter, and I'm missing racing season. I've already missed two events that I planned on making, and it sucks.

 

 

The day after we found this issue, I called Woody at fordstrokers, since he built it, just to see what he thought. I had always heard that if there's some sort of blockage in transmission lines, or coolers, it would cause the converter to push forward, and kill thrust bearings. Of course, that was Woodys response, so my next call was to PA, since they built the transmission.

 

I was a little confused after I got off the phone with them. The guy I spoke to said there's no way something like that could happen. He said if there were any blockage, it would just blow out the vent, despite what I've always heard from other people. He said the check the line pressure at the valve body, and it should be 160-180psi all the time, because its a constant pressure valve body. Well, this was before I pulled the engine, so I drove back up to my buddies house to check it out anyways.

 

I didn't have a gauge that went that high, so despite what he said about a cooler blockage, I figured I'd check in and out of the cooler, just to see. It turns out that I had 65 psi going it, and 30 coming out, and if we bypassed the cooler, it made 45 psi. I called PA back the next day with these findings to see if that was normal, and he told me in his 17 years of building transmissions that he's never had anyone take pressure readings before and after the cooler. I thought that was odd, because I've always heard people talk about it.

 

So now I decided it was time to talk to some other people. I contacted multiple other transmission builders and asked them. Every single one of them told me that was pure BS, and my cooler readings were completely unacceptable. There should be no more than 10 psi drop, and that's exactly what happened to my engine.

 

And that's where we sit now. I hope that's what caused the failure, because I don't have a better explanation right now. I guess when I get the money gathered up, I'll put it back together, and take those pressure readings again. If they're acceptable, I'll drive it, but you can bet that I'll check the end play daily to see if it starts growing, so that I can catch it before it eats another crank.

 

The summer has started off with some terrible luck.

[TexasEd 194]

bummer

[sportsroof69 13]

What's left of the thrust bearing

 

 

Grooves in the crank, where it rides on the thrust bearing

 

 

My motor :(

 

[SM69Mach 68]

DAMN man. Sorry to hear about your luck. I loved seeing the vids of your car running on the strip, since mainly you dont see that much nowadays. Good luck and I hope you are able to get it back on the road soon.

[buening 63]

Regardless, you bypassed the cooler and got 45psi so what was the guys beef? It clearly has too low of pressure and you will just trash your next thrust bearing in short order. I wouldn't dare go through all the effort to reassemble and reinstall the motor/trans until they replace that transmission or you can get it tested to their "preferred method" since they didn't like where you took your pressure readings. To me its clearly the only logical source for thrust bearing failure. Even a poorly assembled motor wouldn't have that much thrust bearing wear. I wouldn't let the issue die with PA and would be sending that thing back or send it to a local transmission shop for them to test it. The longer you let this slide the less likely they are going to rectify the situation, and you may go past any kind of warranty date assuming it had one.

[sportsroof69 13]

PA has a lifetime warranty on all transmissions. They will even refresh it once a year under warranty, and it's guaranteed to 1000 horsepower. My pressure readings tell me that it's a problem with the cooler, and not the trans, so it wouldn't be PAs problem. I'm going to put a different cooler on it when I put it back together, and I'll check the pressures before I go anywhere. If they're the same, then obviously, I'll look elsewhere.

[buening 63]

Ah I'm following you now, had my head up my rear. The 180 was valve body pressure which you didn't check.

[sportsroof69 13]

Correct. I don't have a liquid gauge that goes that high, so I checked it into, and out of the cooler, since it's all I could do.

[DRASTiK 22]

Bummer bud. Keep us posted. Hope you're able to get it back up and running soon!

[sportsroof69 13]

It may be a while. I need a new crank, new bearings, new cooler, and I'll have to have everything re-balanced. On top of hat, the expense of all new gaskets, and fluids isn't cheap.

[LindenBruce 27]

Is it possible your convertor was "ballooning" causing the premature engine thrust bearing wear? I know this can and has happened, I just don't know if did in your case.

 

Also, how about the flexplate being wrong? To much offset? Bruce

[sportsroof69 13]

The converter is a Neal Chance converter, with a nitrous anti ballooning plate, so it's very unlikely that happened. Just to be sure, I called Chance and got the physical dimensions of the converter and measured it. No ballooning.

 

We checked all the things before it was installed, and there's a little over 1/8" converter gap, which is perfect.

[LindenBruce 27]

Okay, this is a real trip. I agree with PA that a fluid blockage would not force the convertor forward. It rides on slip rings and has no pressure pushing it forward or backward. And since you had torque convertor to flexplate clearance it's not the flexplate out of spec.

 

Have you opened up the trans yet? I wonder if a thrust washer/bearing is missing which could have caused the internals to move forward under power and pushed the convertor forward via the input shaft.

 

Just thinking out loud. Bruce

[sportsroof69 13]

Well, the way every other trans builder explained it to me, was that with a cooler blockage, the fluid comes out of the pump, into the converter, out of the converter, and the directly to the cooler. The vent is actually behind all of that. So, basically, you have a blockage that backs up pressure between the pump, and the cooler, and since the vent is behind that, the pressure has to go somewhere and it pushes the converter forward. The fluid travels from the pump (in the transmission), directly into the converter, so when that pressure builds, it pushes on the inside of the converter.

 

That's the same pressure that would ballon a converter, but since it can't, do to the anti ballooning plate, it attempts to push the converter away from the transmission, on the shaft, pushing on the flexplate/crank.

 

That's my very basic understanding of it. It made sense when they drew me a diagram.

[DRASTiK 22]

That's my very basic understanding of it. It made sense when they drew me a diagram.

 

Yeah, pictures are always good for me too :smile:.