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-   -   need help asap (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/need-help-asap-795021/)

88 rx7 drh 10-20-08 11:38 AM

need help asap
 
i have an 88 convert and it has 0 compression in like 2 or three. so i went and got a used 13b with a trans and the guy said he kept up on turning it over tell about three monthes ago and i brought it home and i was turning it over and it was going ok and just stoped.:wallbash: the plugs have some rust on em. but i was thinkin i could put it in the car and have my dad pull me around the block and pop the clutch in 2 or third gear i need advice asap. (and i tried backing the main pully up again but the bolt comes loose)


thanks in advance

88 rx7 drh 10-20-08 11:39 AM

and i was turning it over with a breaker bar

87 t-66 10-20-08 11:40 AM

rusty internals is usually caused by blown coolant seals. did you look through the exhaust ports for broken apex seals? it doesnt turn over at all?

88 rx7 drh 10-20-08 11:45 AM

no it was turning over a little i think it got some rain init cause the guy didnt cover it up over the sumer or something

88 rx7 drh 10-20-08 01:11 PM

should i just put it in?

dot_txt 10-20-08 01:16 PM

No. If its rusted and seized its dead. Probably not even worth rebuilding. Rebuild your old engine or buy a known good condition engine.

88 rx7 drh 10-20-08 01:32 PM

this isnt very rusty it ran great when it got pulled out

88 rx7 drh 10-20-08 01:38 PM

how much would a rebuild cost if i did all the work?

dot_txt 10-20-08 02:28 PM

Depending on the condition of the engine.. Anywhere between 950 and 1500+. That all depends on the condition of the rotors, Irons, and housings. A base rebuild kit from Atkins is roughly 900$. Could be more thats just a guess. If the bearings need replacing then your looking at another 150ish. If your rotors, Irons, and housings are in good condition then you should be able to get away with no more than 1200 if your very careful and systematic. Otherwise if you need to replace Rotors, Irons, or the housings then your best bet it to buy them used here off other forum members.

myersprostatus 10-20-08 02:29 PM

uhh. when i purchased a used jdm motor. i could turn it over with a big racthet and a socket with some effort but not to much, i could hear the thud thud sound as well knowing that theres compression. its sounds like yours is seized.

dot_txt 10-20-08 02:35 PM

The engine should turn over with a breaker bar. It should even be able to be turned by hand (if you have the strength to do it). If he can't turn it with a breaker bar then it is seriously seized and needs to be ripped apart. If its rusting then the internals are probably shot. Not even worth tearing it apart unless its to see if there is anything salvageable inside it.

88 rx7 drh 10-20-08 03:01 PM

but the thing is mine was turning over and going thud thud. from compression

S4GXL 10-20-08 03:08 PM

on this note, i could turn mine by hand on either the flywheel or pulley...like really easily. i could feel a little compression but not even close to what a piston motor has. i assume this is normal because alot of a piston engine resistance comes from the valvetrain as well. nevertheless the car runs awesome. no problems at all.

dot_txt 10-20-08 03:08 PM

The engine that has bad compression on 2 faces? Its blown and needs a rebuild. Simple as that. The other engine is seized and should not be used.

gonetomorrow 10-22-08 09:29 PM

This is very close to my exact question, only with a variation. I bought a project car and pulled the motor. It turns smoothly by rotating the flywheel by hand and I hear the intake and exhaust pulse sounds (inner intake manny and exhaust manny still on motor.) Then I thought, "but the plugs are still in" and got worried. At first I was relieved it wasn't frozen but now I don't know what to think.

dot_txt 10-22-08 11:59 PM

If you hear 6 even pulses coming out of the exhaust port then your probably fine. It will sound more like a "Chug" vs a "hiss" though. You should hear 2 pulses per full rotation of the flywheel. You could still have poor compression but the only real way to test that is to get the starter hooked up and turn it over with that using a compression tester. Good luck.


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