RoFLCoPTeR

Ok i have a 1988 GX with a 13b that was converted to Carburated (runs a 600 cfm Holley carb with mechanical secondarys, Custom intake and a RB header, and MSD ignition, Street port) from Fuel injection. the other night i was driving, everything was fine then with no sudden signs of anything wrong the car idled funny then just died. at this point i tried to restart the engine and it seemed as if the car had instantly flooded itself.

So i called up my buddy to help me tow it home as we had just finished adjusting springs and installing a new wiper switch. we decided as we were towing it home to pull start the car when it was close to my place. so we got close to my home and about a block away i dropped it into second going about 40km an hour and bam started up no problems like nothing happened. after this i was like ok its a flooding issue.

Next day. im heading off to work ( i work at a Mazda dealership) and i went to start the RX7 and it started just fine but then after about 3 seconds of idling it wants to die on me. When the car idles it sounds like im not getting a full burn and i get the typical burbling noise in the exhaust like its a very small backfire but nothing causing a large burst or anything. For a note my car had been running rich at this point and i forgot to re tune the carb.

So with the help of my buddy i babied the car to work nor putting to much stress on the engine and we get it into the bay at work.

We check the spark plugs, completly normal, little bit of carbon due to running rich but nothing was fouled or out of the ordinary.

We check the Coil's and my MSD ignition to check if it is actually firing, once again everything checks out OK, everything is firing.

next i check my fuel pump and regulator, im getting fuel ( at the time i did not have a fuel pressure tester, this will be done on monday) and the pump and regulator seem to be work just fine.

finally we check compression, it was around 65 front chamber and 70-75 rear chamber. last time it was checked i was sitting at a solid 90-100 psi.

now up until this day, as i said earlier the car was running a little rich, but it was running at full power with nothing wrong.

Me and the guys at work have come to the conclusion that it is either fuel delivery, or i have a carbon build up and one of my Apex seal/springs is sticking and not making full contact with the housing causing the low compression.

Im looking for any advice in how to go about restoring the compression. idea ive heard so far is running ATF through the chambers and lube things up a bit then let the car go through a can of SeaFoam and really clean everything out really well.

if anyone has ideas or suggestions please let me know so i can go in to work on monday with an open mind and some ideas on how to tackle the problems. Thanks ahead of time to everyone who replies.

84stock

iTrader: (5)

If it is running too rich it will drop compression due to the fuel washing away the lubrication. I would check ignition, perhaps you have a weak or bad coil. What fuel pressure are you running?

RoFLCoPTeR

i assume my fuel pressure is running at 6-7 psi, im checking on monday, also the carb has been running a little richer then normal so ill have to check that out.

84stock

iTrader: (5)

You need a fpr with a guage as well.

misterstyx69

iTrader: (142)

I'd check the Needle and seat in the carb.If it is Stuck open because of Crud,then it will flood out the engine..it doesn't take much Crap to get the Needle to not Close up after the Float is at the Appropriate level.

RoFLCoPTeR

would the engine still idle at a running temperature with the Needle and seat stuck? also can that cause me to have the low compression due to the dumping of fuel?

polito Racing

iTrader: (1)

+1