ok i bought a 90 gtu with a jdm tII swap in it. at first we thought maybe the apex springs are gone but when we charge the batt and hooked it up the motor tryd to turn over. no grinding sounds or anything it was trying to start but just couldent. the guy i bought it from said it had no comp. now me and a friend of mine were reading thathe apex seals could be lock in the compressed position ?

 

Do a compression test and report back, it's possibly a blown motor.

 

It's missing the ECU? It won't start without one if that's the case.

 

no the ecu is there full jdm swap, as soon as i get a tester i will get the numbers back 2 you guys asap.

 

Rofl, by having no comp he ment compression not computer

 

ok so heres a lil update on whats going on. so the engine sat for maybe 18 years, give or take, and i cant get it to start, havent gotten the compression tester yet so i dont have any numbers 4 you guys. however what i have read is that if synthetic oil was used on the engine(and probaly was seeing as how it was a turbo) the buring of that oil leaves nasty gunk. so after setting for so long that gunk along with the carbon can cause what we thought was carbon lock. whe i called the guy that own it b4 me he asked could that cause the engine to be stuck in the "ON COMPRESSION" ?? i assume that means stuck in the compression strok of the engine, wich i read can happen. i have sprayed 2 cans of carbon eating liquied into the engine put a can of marvels oil in the gas and oil. after we did that it was trying to start but seemed like it was just not enough. now i called a local performance shop and the guy had rebuilt a 13b 4 years ago and worked on other 13bs, he said that he has had to drag the cars down the road and pop the clutch just to get them to start because they sat for so long it neede extra UMPH to get it going. he also said that i needed to check my injectors that they can become stuck open and just flood the engine all to hell. an last night when i took out my plugs i could smell plenty of gas, but the plugz looked good lol. so thats the updates so far... any ideas ? i know i still need the comp numbers but i probaly wont be able to get those till sat but the previous owner had it test (what the number were idk) he just said it had no comp and the engine never ran.

 

ok i try today to turn the car over with the plugz out so i could hear what was going on with the engine. now what i heard sounded like ireagular compression. But from what i have been reading the apex seal and spring can become stuck as if the apex seal was chipped, or broken. on the vid i watched about unlocking your engine it stated thath e engine needed to be rotated back and forth and the apex seals needed to be pushed in and out to work out all the carbon and gunk build up that comes from synthetic oil, (if used). so now i wonder if thats true? can the apex seal sound broken or chiped if it has carbon lock ? the engine does build oil pressure when i try and start the car, gets up to maybe 25-30 odd but because it doesnt turn over it doesnt build anymore. can anyone help me ? anybody at all had this problem b4 ? also how is a sure way to check for carbon lock ????? and ive search but maybe some you have found a write up about it on other websites any info will help me out thanks

 

A compression stroke is an engine cycle, not an apex seal position. If the engine is turning over, it's not stuck in the compression stroke. Just cause you're smelling fuel does not mean it's making compression. Once you get your compression results, and if they are bad, you should find out if it's stuck apex seal due to carbon buildup. If it is, Check this thread: https://www.rx7club.com/showpost.php...93&postcount=7 Automatic Transmission Fluid is the most used solution for stuck seals, others have had luck with fuel injector cleaner. Either way, you'll have to take the turbo and manifold off to access the exhaust port.

 

Do a compression check. You are probably trying to trouble shoot a blown engine. Or you can take off the turbo and manifold and visually check the apex seals through the exhaust port.

 

im thinking the same thing now, however if it is a blown engine wouldent there be some kind of metalic noise comming from the engine ? either way i plan on taking the turbo off and doing this check 2day.

 

No there would not. a blown seal may also be the cause of the irregular sounding pulses.

 

ahhhh ok i was miss informed about the seals then

 

I had the same problem, I bought a 87 tII and was told by the previous owner it needed new injectors or something so i thought,"great, easy fix!" ...turns out (after 3 weeks of trouble shooting and internet seaching) the motor really had no compression. Just pulled the motor/tranny last week and comensing teardown!