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-   -   Hand crank compression?? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/hand-crank-compression-961153/)

Bct907 07-07-11 06:49 PM

Hand crank compression??
 
did some searching on here, found compression test numbers, but none I found specified they were hand cranked numbers....

so, bassically, are hand cranked numbers good or bad at 65 psi? just put a socket on and cranked it by hand 5-6 times, came out 64-65 each time.

I know it is supposed to be higher when in a running car, but again, this is just by hand.

misterstyx69 07-07-11 07:20 PM

needs to be warm and cranked at 250 rpm( starter speed).full open throttle.
If you are just hand cranking,then Just pull a trailing plug and listen for 3 solid wooshes..It won't give you any "numbers" but it will give you an idea that the engine is ok.
but IMO 65 psi on hand cranking sounds good too...

Bct907 07-07-11 09:12 PM

also, it wasnt a rotary compression tester.. I dont think.... Found an engine on cl, guy tested it, gave me 65 psi is what it read after 5 or 6 hand cranks

Bct907 07-07-11 09:24 PM

also, not sure how to ask this guy to crank it while it is warm, the engine is out of the car. and how do you crank it by hand at 250 rpm???

Bct907 07-07-11 10:00 PM

update on the engine. it has been sitting in a car for the last 4 years, then was pulled and put in a garage for the last year. I think that 65 psi after so long is actually impressive, but I called the guy back, told him to oil it up a bit, try it again, see what numbers he pulls. what is everybodys opinion?

jerd_hambone 07-07-11 10:05 PM

If it's cranking by hand, then it's possibly a good core. What are your plans for the engine?

misterstyx69 07-07-11 10:09 PM

If you have the engine out of the car and Trans attached,,then attach the starter Too.. hit the starter with 12 volts.
it will roll the engine over and you get a Compression reading.
Yes,it is that simple!

Bct907 07-07-11 10:11 PM

my plans for the engine are to simply hope to God it is in decent enough shape for me to shove in my car so I can get to work lol. I just happen to drive very aggressively on the freeway... that's all lol.

SpikeDerailed 07-07-11 10:34 PM

65 from hand cranking it good. go check it out, take the exhaust mani off and peek in there.

Bct907 07-07-11 11:26 PM

what would i be looking for with it off?

jerd_hambone 07-07-11 11:32 PM

Negative amount of apex seals haha

Bct907 07-07-11 11:36 PM

weeellll, I think this engine is toast, as he just told me the 65 psi reading came form when it was cranking with a battery... is it possible the numbers are low becuase it has sat for so long? and also he said the battery was about dead when he started cranking it... I really do not mean to be such a pest, but i really only have so much money to work with right now... trying to get the best route to running car... you know?

jerd_hambone 07-07-11 11:51 PM

Whats the price on the engine? And whats your budget?

Bct907 07-08-11 12:25 AM

he is asking 400 for engine fully dressed, wiring harness and transmission. all are from a 92 fc. my budget is.... about 800 bucks....also have about zero tools... so I really need a running engine for very cheap just to stick in the car and get back and forth to work...

Bct907 07-08-11 01:38 AM

is it possible to have low compression numbers due to the fact it has been sitting for 5 years and needs to be tuned up? oiled? something?

Bct907 07-08-11 04:49 AM

........bump

jerd_hambone 07-08-11 09:42 AM

What year is your car? 92 FC, I think they only made verts that year. May be wrong though.

Some Marvel Mystery Oil or any kind of oil will help with compression, but 65 is low.

Have you tried checking here?

Bct907 07-08-11 01:19 PM

yeah, I have searched for engines here, in the west classifieds, as far back as December.....

20Bforme 07-08-11 01:21 PM

you looking to buy an engine?

Bct907 07-08-11 01:43 PM

HELL YES I WANT AN ENGINE! lol. needs to be a solid runner though.

jerd_hambone 07-08-11 01:46 PM

What year is your car?!

Bct907 07-08-11 01:51 PM

NINETEEN NINETY ONE!! lol

jerd_hambone 07-08-11 02:04 PM

Haha okay. Did you try the normal for sale section? Not too many people use the regional sections.

Bct907 07-08-11 02:14 PM

I did some browsing, but I am pretty limited on cash, and I wont be able to pay for shipping if its too far, you know?

jerd_hambone 07-08-11 02:22 PM

Yeah, I know the feeling.


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