Ok, here is the question.. replace the crank only with bearing and thrust washer, rebuild the whole thing or Ls swap.. here is the problem. Few months ago my yj with blue print and balanced motor with a mild hot cam with the three speed automatic transmission. The transmission burned up on me. So a bought a AX15 and decided to swap to a manual. Told it was a working transmission, but after installing I found it had no reverse and hard going into 5th. So I rebuilt it. Went to install it and while mating it to the motor. I noticed the flywheel moved and I mean a lot. Put my dial indicator on it and I had almost 3/8 of an inch…. Ouch. So I dropped the pan and pulled the number 3 bearing cap to check the thrust bearing. Of courses it’s shot, but not as bad as the crank. The crank is worn bad enough to not be repaired. So… everything else seems ok, but the timing chain. It has ton of slack in it. Engine was running fine, but this isn’t good. So what would you jeepers do? Crank was only worn on one side, looks to me that it was being pushed against. Any ideas what caused it also. I got about 23k in this set up. Thanks everyone, Matt
Crankshaft end play
- Thread starter matthewcamp1978
- Start date
Flyer58
YJ Enthusiast
Before making any decision I would dig deeper into why that wear happened to the bearing in the first place.
Did the AX15 input shaft bottom out in the fly wheel and push the crank forward?
I'm just guessing but I'd hate to rebuild the engine only to have it happen again.
Did the AX15 input shaft bottom out in the fly wheel and push the crank forward?
I'm just guessing but I'd hate to rebuild the engine only to have it happen again.
I only had the AX15 in for maybe a few minutes with the engine running before finding out I was bad. I pulled it out and rebuilt it. After I rebuilt it and went to put it back in is when I noticed the amount of end play. It had the atomic 999 in it before. Think maybe the shop that rebuilt the automatic transmission maybe gave me the wrong torque converter. But I didn’t notice a clearance issue installing it, or when I pulled it after I burned it up. I did get about 23k miles with it in there. And on the motor.
I would guess tq converter pushing on it base on this.
If the transmission cooler lines have been pinched or crimped, excess pump pressure can cause the converter to act like a hydraulic ram, continuously jamming the crank forward. If the vehicle in question has undergone an engine replacement, make a point to closely examine the transmission cooler lines for any signs of kinking, collapse or other problems.
When beginning to diagnose a thrust bearing failure, instead of suspecting improper engine assembly, first consider the transmission-related issues that can introduce undue forward loading against the crankshaft. Check to see if any external changes were made, such as replacement of or installation of an additional cooler. Ask the customer if any performance modifications were made to the transmission. Verify that the correct flexplate and flexplate bolts were installed, and that the transmission was installed with proper alignment to the engine block (dowel pins in place). If transmission-to-cooler pressure is too high, and the return line pressure is lower, inspect for restricted cooler and cooler plumbing.
If the transmission cooler lines have been pinched or crimped, excess pump pressure can cause the converter to act like a hydraulic ram, continuously jamming the crank forward. If the vehicle in question has undergone an engine replacement, make a point to closely examine the transmission cooler lines for any signs of kinking, collapse or other problems.
When beginning to diagnose a thrust bearing failure, instead of suspecting improper engine assembly, first consider the transmission-related issues that can introduce undue forward loading against the crankshaft. Check to see if any external changes were made, such as replacement of or installation of an additional cooler. Ask the customer if any performance modifications were made to the transmission. Verify that the correct flexplate and flexplate bolts were installed, and that the transmission was installed with proper alignment to the engine block (dowel pins in place). If transmission-to-cooler pressure is too high, and the return line pressure is lower, inspect for restricted cooler and cooler plumbing.
Thank you, I’m thinking it was the torque converter. I built the motor and I had it blueprinted and balanced. All my tolerances were spot on. I’ve built a few motors before. When I built the motor I decided to rebuild the transmission also. First time doing so. It only last two days before it burnt all the clutches. So I had a transmission shop rebuild it. I swear they used the same torque converter and just painted it. Anyways, I asked what I did wrong, and he couldn’t tell me. Said everything looked good besides the clutches being smoked. So I assumed that my cooler was to blame. So I blew it out and threw the new rebuilt transmission in. That was about 20k miles ago. But the transmission never felt right. And would make a weird tick sound on step grades. Then it finally went belly up. Got supper hot and lost all power. I limped home and decided to go with a manual. So I have all the part and ax15 ready. But now I discovered the end play issue. Just wondering now if I should just check all the connecting rods, pistons, cam, ext… if they all are is spec and good. Then just replace the crank and crank bearings, thrust bearing. And oil pump while I’m in there. What’s your take on that? Thank you everyone for your replies.