i couldn't think of a better title, but here is the problem.

when i first got the atkins motor in, i filled the coolant up incorrectly and wasn't aware that the block was still empty. well, started the motor up and ran ok i guess but the temp rose fast. then started to smoke out the exhaust and around the turbo. i shut it off. didn't know what the hell was going on so i let it cool and did it again, only this time i took it around the block to see if getting air to the radiator would help. well, it didn't and by the time i got the car back in the neighbor hood, the temp guage was pegged so i shut if off and coasted home. well, figured out what was wrong and then coolant temps were fine.

ok here's the thing, my compression never really got any higher than 100psi throughout the 8k miles i put on it and now the compression is less than 60psi and runs rough. i was wondering if overheating the motor that long ago was the end cause of the failure. it's hard to believe that the apex seals are gone after 8k miles.

if any moderators think this thread is totally retarded, just lock it. i'll understand.

thanks for all your help

 

oh, and will evidence still exist that the motor has been overheated? if someone takes the motor apart, will they know that the motor had been overheated?

 

dp

 

Its possible that you will see discoloration on the crank shaft, stationary gears, or other machine finished surfaces. You can measure the plates for step wear. Check out the FSM or haynes manual.

 

well, the thing is, if there are existing marks of overheating, then i won't even bother sending my motor back and just rebuild it myself. it most likely won't be covered under warranty if it has been overheated.

looked in the exhaust ports when i got the motor out, everything seems to look fine. no broken apex seals that i can tell, and for the most part, the side and rotor housings have a mirror finish. however, at the very edges of the rotor housings, there is some disscoloration possibly from where the corner seals touch. it's on both sides of both rotor housings. i poken my finger inside the exhaust ports to see if i could feel any ridges on the edges oh the housing face, but seemed smooth. i've never taken a motor apart before so i don't know if that disscoloration is normal. other than that, everything appears to be in check...without taking the motor apart.

 

Overheating will deff grenade an engine. Well it will a piston engine (trust me) and I am sure a rotary is the same.

 

well, i overheated it and then drove around for 8k miles. i'm just curious if the overheating did anything, and if there is still visual evidence that it had been overheated?

 

well ive overheated the **** outta my engine twice now because of a cracked radiator. car runs fine, 3000 on rebuild, im somewhat worried but confident that it didnt do any damage. The only real way to tell is tear the engine apart and look to see whats going on inside.

 

If overheating didn't cause water o-ring failure, then there should have been some water left in the bottom of the block. If there was, the engine probably didn't get hot enough to do any damage (but don't rule it out).

Visual evidence of dry-block (no water) overheating is easily seen on the combustion-half of the side irons. When they get hot, they'll change to a dark blue color on the inside of the engine. This means the metal has gotten hot, hardened, and shrunk. It's impossable to get rid of, and it also means you've most likely (but no absolutely!) got some serious distortion on those housings. Even if you have them lapped, they'll wear unevenly. The only sure way to tell is to tear it down and look for yourself.

 

the motor is still under warranty, unless they can tell that it has been overheated. i told them that i lost compression and they said, "ship it to us and we'll look at it". well, if they look at it and can see that it has been overheated, then they won't fix it for free and i'll have to pay for the shipping both ways, even if the overheating didn't cause the compression loss. and if i tear it apart myself, they certainly won't warranty it. i wouldn't be so worried about it if it didn't cost so damn much to ship the engine, otherwise, i'd ship it and cut my losses if they don't warranty it.