Hello,

I have a 12a in my offroad car. I have been trying to start it for two days,but i can't get it to fire. I have fuel & spark but still not firing.. I did a compression test with a standerd spark plug tester and got 55 pounds out of all four plugs. I also put my hand over the carb when I try to start it and the front rotor is sucking more air then the back. Does anyone have any pointers???

any background on what happened to it before it decided not to start? ie: been sitting for years.,, drove the **** outta it and now it won't start,.etc ?

I got it from a friend and he said it was running in his car. It has been sitting about four years. I'm going to take it to mazdatrix this week. I hope they can get it started because we are going out to the desert on new years. I did a compression test with the standard spark plug test and got 55 pounds. Do you know if thats good??Please give me some pointer's..



Thanks Shad

Quotes are from "Lightning in World of Thunder" web site.

http://www.scuderiaciriani.com/rx7/c...sion_test.html



"Warm up engine to normal operating temperature, then stop it.

Allow 10 minutes for the exhaust manifold to cool.

Remove the front and rear trailing side spark plugs."



The schrader valve is the needle valve at the bottom of the compression tester.

"Remove the schrader valve from a standard tester to test compression yourself. Readings come very fast so you must have a quick eye. "

"Fully depress the accelerator pedal and crank the engine for 5 to 10 seconds. Note readings. "

55 is definitely not good.



With my 13BT the factory floor is 85 psi and my c/r is 8.5:1. You should have a c/r of 9.4:1 for sake of a reference point. They will run with much less but in my mind 65 is the absolute limit. You get bad hot-start flooding with #s this low.



This graph is a 87 13bt of unknown mileage tested at sea level.