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-   -   God Its A Nightmare! (https://www.rx7club.com/1st-generation-specific-1979-1985-18/god-its-nightmare-405288/)

-xlr8planet- 03-16-05 09:49 PM

God Its A Nightmare!
 
ok... Im dirty, tired and I smell like gas and oil... again

after realizing my car was trying to start on a 45amp battery I tried another battery tonight

since Im unable to crank start the car, I push started it and let it warm

Then, I proceed to mesure compression.

The thing is this.... it only read 25psi on both rotors

CAN THIS BE???

the car sometimes crank starts, idles and runs fine

The tester was a piston tester...... that might be it?

FB II 03-16-05 09:55 PM

rebuild :p:

rxseven07 03-16-05 10:01 PM

mmo the bitch, do a search, should make it last for a little while longer

RRTEC 03-17-05 12:01 PM

Sell me your non-US spec Front lenses..... To help pay for your rebuild....

cdrad51 03-17-05 02:48 PM


Originally Posted by -xlr8planet-
ok... Im dirty, tired and I smell like gas and oil... again

after realizing my car was trying to start on a 45amp battery I tried another battery tonight

since Im unable to crank start the car, I push started it and let it warm

Then, I proceed to mesure compression.

The thing is this.... it only read 25psi on both rotors

CAN THIS BE???

the car sometimes crank starts, idles and runs fine

The tester was a piston tester...... that might be it?


The only problem with the piston tester is that it won't show all 3 chambers, but only the highest one, which would mean you have 25 psi in your strongest chamber :eek:

mcnannay 03-17-05 06:28 PM

hmmm, i was under the impression that you didn't check compression while the vehicle is running

cdrad51 03-17-05 07:25 PM

He didn't say it was running WHILE checking compression, and I hope he wasn't. I think he warmed up the vehicle, shut it down and then proceeded to check compression.

-xlr8planet- 03-18-05 02:27 AM


Originally Posted by cdrad51
He didn't say it was running WHILE checking compression, and I hope he wasn't. I think he warmed up the vehicle, shut it down and then proceeded to check compression.


exactly.

and no one told me yet if the car would even be able to idle steady (as it does at 750) with only 25psi of compression

mwatson184 03-18-05 10:24 AM

most people go by 120ish compression = new
90ish compression = ok, but start saving for a rebuild

You are at 25, hopefully that number is off. Your motor is probably really flooded which causes a large drop in compression. Try unflooding your motor and giving the compression test another whirl. If that is not the problem then 25psi probably means blown seals.

Marques

RRTEC 03-18-05 10:25 AM

yes it will idle and drive... I had an 83 with 0 psi on the rear (all 3 seals were shorn) it was shovelling oil into the exhaust, (sounded like a fryer at MC-donalds) and only 70 psi on the front, it would idle and I drove it around, it smoked like a chimney and wouldn't go over 40mph but it ran......

cdrad51 03-18-05 12:02 PM

hahaha so true, that's how my car is right now. Front rotor 0 psi, rear rotor 90 psi. But it's not drivable. It backfires so much and has so little power that is basically useless.

smnc 03-18-05 02:20 PM

I stated losing compression on my rear rotor last year...
My front was at 80psi and the rear was at 10psi...
The car stated a little hard, but was probably putting around 25hp to the road, lol....

I had to floor it to crawl up hills...

Now I have a new engine...:D

-xlr8planet- 04-24-05 01:24 PM

Still 25 psi. But the car pulls really strong, no smoke and revs like hell

I think the number its probably off...

nimrodTT 04-24-05 01:38 PM

Your tester might not be reading correctly, look for evenly matched pulses and don't worry about the low numbers if it runs fine.

-xlr8planet- 04-24-05 01:40 PM


Originally Posted by nimrodTT
Your tester might not be reading correctly, look for evenly matched pulses and don't worry about the low numbers if it runs fine.

each pulse looks exactly the same on both rotors even if you move the engine by hand

if you do so, sounds whooosh

if you crank it, goes put put put

Elysian 04-24-05 02:39 PM

when my repu lost all the apex seals on the rear rotor i had to drive it home... that bastard would hold 60 in 4th gear on 1 rotor... couldn't use 5th... but it was a street ported 13B with a holey 600 cfm carb, probly why...


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