Like I had said before.. We got the rx7 running, but only for a brief time.. I got to drive it for appx 2000 ft.. I got it back tothe house, went in to get something to drink, came back outside and the car died.. When we tried to restart it , the car would try to turn over. but wouldn't.. We let the car sit for a little bit so it would cool down and get unflooded.. When it came time we tried to start it again and had to feed gas to the carburator to prime it and get it started.. The rpms shot up to appx 4500 and then dropped quick.. When it hit appx 2500 the car died again.. We couldn't get it started again after that.. We went back a week later and tried again when the motor was cold.. It wouldn't hold the rpms.. We are thinking that it is loosing compression somewhere some how.. The motor was sitting appx 11 yrs prior to us getting it started.. Can you guys help us in any way.. We are thinking that we are going to have to have the motor rebuilt or replaced.. Suggestions would be nice.. Or at worst sell it for appx $1500.00 obo...

 

What did you do prior to trying to start it after sitting that long? At a minumum, you should have changed the spark plugs, oil, coolant, fuel filter, drained the fuel tank and added fresh gas. The ignition system, rotor, cap and wires should be checked/replaced also.

If you didn't do these, do them. More than likely the old fuel in carb has dried out and left the internals varnished up. A carb rebuild is probably needed. The same thing happens to the engine seals. The volatiles evaporate out of the carbon buildup, the carbon hardens and the seals stick, which will show as low comprssion. You can soften the carbon by pouring Seafoam or atf down the carb, turn the main pulley 1/2 turn, repeat a total of 6 times. Then let the engine set for a few days, turning the engine over by hand 2 full revolutions twice a day.

When you are ready to start the engine again, pull the plugs and clean them, better yet, install new ones, NGK or Nippon Denso, not Autolites.

 

***You can soften the carbon by pouring Seafoam or atf down the carb, turn the main pulley 1/2 turn, repeat a total of 6 times. Then let the engine set for a few days, turning the engine over by hand 2 full revolutions twice a day.***

Just in case you do not understand "atf" that would be automatic transmission fluid. I pass this bit of information on because I am not new to a rotary motor & I don't have a clue to what Seafoam is. Anyway the atf works well at freeing up the rotary seals. Been there a couple times.

 

Seafoam is used to clean the fuel system and engine internally. It is usually added to the gas tank. It works slower and is not as harsh as atf but may not be up to the task of softening dried out carbon deposits. One of these days I need to test them side by side.

 

Ok.Well i did drop the gas tank,changed the pugs and wires,droped the oil,,new coolent.Th the carb has been rebuilt and the flots are set right. The other thing what about it not holding rmp..

 

Check the compression and look for vacuum leaks.

 

ok will do and will let yal know. Also do u think it would be all the seals in the block could be bad and the wipers on the rotars could be bad

 

^ What are you talking about?

 

Lol

 

Make sure you're getting fuel through the lines as well.

 

I am getting fuel. I know that. i had 2 reset the flots on the carb, b/c it was flooding the motor.so i know its getting gas.The fuel pump is good.the fuel filter is good. my gfs dad tested the compression.The car has compression when it is cold,but when the car gets to running temp.you can kiss the holding rpm and restarting the car. I have pulled the starter and i have had it tested. the starter is good. so on the 3rd when i get paid i will go buy new vacum lines and see what that does. what do yal think

 

You are supposed to do the compression test when the motor is at operating temp.

 

Oki.how do i do the compression test.If i cant get the 2 stay running it will not hold rmp.If i sit on the gas.which then i would have 2 keep the rpm over 2.5 so the motor will stay running.so how do i get the car 2 stay running.like i also said when we have got it 2 running temp the car will not start again.

 

The compression testing procedure can be found by doing a search.
When it will not restart, have you checked to see if it still has spark at both trailing and leading. Have you also checked to see if it is getting fuel when it acts up.

And you don't have to have the motor start to check the compression, it just has to be at operating temp.

The only difference in diagnosis between our cars and a piston car is the compression testing.

 

Testing it cold will give you a general idea of compression, warm is more accurate though. As doc said, it doesn't, and should not be running when tested. Warm up the engine, then disable fuel and spark, testing is supposed to be performed at cranking speed, around 250 rpm.

Testing proceedure is in the FSM, link is in my sig line, but wankle.net has been iffy lately. If you can't log on, there is a link to another site in the 2nd gen section, archives I believe.

 

Since the engine has been sitting that long, I would definitely grab a can of seafoam for it (check with Napa, Autozone, etc.). The apex seals (wipers) can get clogged with carbon and then they won't move in and out of the slots like they should, which will reduce compression. Seafoam will always help your motor run smoother and produce more power.

I would also check the timing if you can get it running long enough. This will often cause "starts cold, but not when hot" issues. Good luck!

 

ok. i got the car started cold.then i let the car get the running temp put the seafoam in as the bottle said "1/3 of 1 pinte of the can". then shut it off for 5 minutes and restart the car. well i had a lil problem. the battery did not have enough charge left. so it all most started but battery fucked that. well i got my wifes trucks and started charging my battery and help with some power 2 get it started. well in doing that the starter ******* went out on me. after about 6 trys on starting the car. one thing i did notice, is that when we had the casr running the nite be4. it was miss firing bad.what got me was the car never back fired.



so i was thinking that i would replace the spark plugs, spark wires and distributor cap. i know i need the timing check but i dont know anyone in this arkansas that will do it. mazda thamself told me "HELL NO". then u have the guy that think they know what they car doing but dont know anything. i have called all the import repair shops. tell told me they dont work on rx7 or rx8. so what to do.