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Force Fed 05-20-07 01:15 PM

Starting issue (searched)
 
I have to hold the throttle open a bit to get my TII to start up, when it does it smells a bit rich until it burns off. TPS adjustment didn't change it. I think the compression is a bit low, haven't checked it since but when it flooded out on me and I had the plugs out, it had 75 in the rear and 50 up front, no atf added yet. So I figure it has around 75-80 w/o being washed out w/ fuel :) Will this cause it start like this?

I still need to adjust the BAC and possibly idle hard stop, I had to zip-tie the fast idle lever up to keep it from idling at 2k all the time, the t-wax doesn't work right. I have fiddled with them before and nothing has changed how it starts, if I don't hold the throttle open a bit it won't start on it's own. It'll try a little then just flood out.

Go48 05-20-07 06:53 PM

How did you check the compression? You need to know the compression on all faces of the rotors. If you just used a regular compression tester and let the pressure build up from multiple rotations of the rotors, that won' t tell you much. You can still have a bad apex seal and that technique will not pick that up. Get a good compression test with a compatible rotary-engine compression tester, and make sure the engine is warmed up and the accel pedal depressed all the way when cranking the engine.

Force Fed 05-20-07 08:46 PM


Originally Posted by Go48 (Post 6960208)
How did you check the compression? You need to know the compression on all faces of the rotors. If you just used a regular compression tester and let the pressure build up from multiple rotations of the rotors, that won' t tell you much. You can still have a bad apex seal and that technique will not pick that up. Get a good compression test with a compatible rotary-engine compression tester, and make sure the engine is warmed up and the accel pedal depressed all the way when cranking the engine.

Sorry I should have specified. I checked it w/o the check valve in, got 3 good 75psi bounces in the back, 1 75 psi bounce and 2 50's in the front. The front rotor was flooded worse though it seemed. Also the engine wasn't warmed up either, as it wouldn't crank.

Go48 05-21-07 10:03 AM


Originally Posted by Force Fed (Post 6960541)
Sorry I should have specified. I checked it w/o the check valve in, got 3 good 75psi bounces in the back, 1 75 psi bounce and 2 50's in the front. The front rotor was flooded worse though it seemed. Also the engine wasn't warmed up either, as it wouldn't crank.

Those numbers are below the Mazda recommended minimum compression spec of 85 psi. But, as you said, the housings may have been cleaned of oil needed to support compression (I doubt that, but it could be). Also, keep in mind that the Mazda spec is for an engine cranking speed of 250 rpm and the location at sea level. So, if your cranking speed is very low, the actual compression may be higher than the numbers you got.

Fully charge the battery, de-flood the car, warm it up and have a good compression test done before giving up on the car.

Force Fed 05-21-07 11:16 AM

Aight, I'm gonna try and fool w/ the idle settings some today and see if I can get it to idle decent, then I'll take it for a spin round the block and check it.

BTW I put new intake gaskets on a month ago, pumped a lot of atf through the chambers while I was at it to clean them out good and help the apex seals some, it sat w/ atf in it for 2-3 days. Didn't change how it started up though. Also, it seems to run fine once cranked, other than a low, slightly rough idle.


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