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-   -   New Engine Won't Start (https://www.nopistons.com/3rd-generation-specific-18/new-engine-wont-start-29792/)

Rotorfreak 12-05-2003 03:26 PM

Just had the new block installed... I tried starting it but it did not.. so i had the mechanic do a compression test... it came to around 350 somthing he said normally it should be 1200 ... then we took the same gauge and checked another car (Honda) the guage showed 1200....



Can it be that the new engine has bad compression?? or what else could it be... its a rebuild street ported engine...



Need help Urgent

sidewinderx7 12-05-2003 03:52 PM

1200? lol.. i think you need a new mechanic :-p



compression should be 90psi in both rotors. Thats average compression. No less than 80 .. thats bad

treceb 12-05-2003 03:53 PM

put a lil MMO or ATF to build compression. thats what i did to get mines started.

im assuming all other aspects have been gone over at least twice, fuel, timing, spark...and make sure u got a very good battery.

treceb 12-05-2003 03:54 PM

that all depends on what measuring system hes using. the comp test on my FD varied from 9.3 to 9.8...

turbovr6 12-05-2003 03:54 PM

compression on a rotary is different then a piston engine. to do an accurate test there is a special tool for the rotary, you can use a standard one if you know how to convert the #'s

Rotorfreak 12-05-2003 03:57 PM

i think in psi it was less then 60psi.... but the mechanic told me that i might need something to free the engine a little...



i don't know what ATF or MMO is??

treceb 12-05-2003 04:00 PM

Automatic Transmission Fluid



Marvel Mistery Oil



do not pour loads of that stuff in neither.

Rotorfreak 12-06-2003 03:57 AM


1200? lol.. i think you need a new mechanic :-p



compression should be 90psi in both rotors. Thats average compression. No less than 80 .. thats bad


It was less than 50 psi.... but ppl are telling me that i need to crank the motor a little and then compression will build up... Is this correct? Also the manual i got from the tuner in japan says that my front rotor had 7 compression and the rear rotor had 9 when they tested it in japan at 200/250 rpms but over here it is much less... Can it be that they have lied? or does the engine need some lubrication time??



i am very confused cuz i have paid alot for it... I told the guy who bought and imported the engine for me immediately of the problem...



Need Help

Racer X 12-06-2003 04:45 AM

Did you try a pull start on the motor?Alot of rebuilt motors need to be pull(bomb) started the first few times till the compression builds up.If you have less than 50 psi right now tho your motor doesn't sound to healthy.Get it running and test it again tho just to be safe.

TyresmokinRx7 12-06-2003 04:56 AM


Originally Posted by sidewinderx7' date='Dec 5 2003, 01:52 PM
1200? lol.. i think you need a new mechanic :-p



compression should be 90psi in both rotors. Thats average compression. No less than 80 .. thats bad

I'm thinking that the gauge is reading in KPA, that's why the numbers are so high.


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