Can’t get this car to run
03-24-18, 06:16 AM
#1
Junior Member
Thread Starter
Can’t get this car to run
Hey guys. This car has been giving me so many headaches but I’m still determined to get her running so I can start restoring her to her former glory. It’s an 85 gs with around 109,000 miles, bought it from a guy on Craigslist who knew nothing about rotary, said the carb needed to be rebuilt and it should run just fine. I rebuilt the first carb and it started up good but wouldn’t idle properly. So after many attempts of taking it off and messing with it I ended up stripping the banjo bolt holes so that carb was pretty much out of commission. Then I found a 79 rx7 on Craigslist a guy was parting out. Bought his carb, even though it was old and rusty, and rebuilt that one as well. Not knowing any better I messed with the floats and it ended up either flooding or running too lean and wouldn’t idle. Tried everything to get that one working good but finally gave up and just bought another carb off the forum. Looked in great shape so I put it directly in without messing with it much and same problem as before, it won’t stay idle. Is there something I’m missing. Everything I look up is guaranteeing that it’s a fuel problem. I’ll try to post pictures later to see if you guys see anything that I don’t. Thanks
03-24-18, 07:50 AM
#2
theres alot it could be, my first question would be
how long did the car sit before you bought it?
If its been awhile, the entire fuel system should've been rebuilt/cleaned before putting a rebuilt carb on it
also, if its been sitting for awhile, theres a possibility that there are stuck apex seals and side seals and its not firing on both rotors, easiest way to find that out is a compression test
you may also have a major vacuum leak, or timing could be off, or just plain bad plugs, or cap and rotor. The old 12a was pretty tough, but like any rotary, one good overheat can kill it
I would start with a compression test, then rent a fuel pressure tester and check your fuel pressure before AND after the fuel filter, then go from there
how long did the car sit before you bought it?
If its been awhile, the entire fuel system should've been rebuilt/cleaned before putting a rebuilt carb on it
also, if its been sitting for awhile, theres a possibility that there are stuck apex seals and side seals and its not firing on both rotors, easiest way to find that out is a compression test
you may also have a major vacuum leak, or timing could be off, or just plain bad plugs, or cap and rotor. The old 12a was pretty tough, but like any rotary, one good overheat can kill it
I would start with a compression test, then rent a fuel pressure tester and check your fuel pressure before AND after the fuel filter, then go from there
03-26-18, 02:43 AM
#4
Yeah you definitely dont wanna mess with the floats. I dropped mine on the ground. On the floats, their levels seemed fine, and I didn't try to adjust the floats or needles seats, I dropped it in the dirt lol. (Got carb cleaner in my eye) Cleaned it all up stuffed it back together runs great. But because i dropped the floats on the ground, I bought the front and rear float from Atkins, and I can get the real mazda needles if i need them, If you might need floats I'd order them now, because Akins only has like 12 front and 3 rear left. My carb still leaks a little bit of fuel from the main body gasket after sitting (will make my own gasket of thicker paper next time) other wise the car runs like a top. The secret to starting the engine first try, as I learned from my dad, is 10 Pumps and then hold the gas a little while cranking. Seems to work everytime, I also like to pour some premix down the carb for each start, because with a high mileage engine I cant over lubricate it.
03-26-18, 10:07 AM
#5
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I had an 85 (IIRC) turbo which ran fine, but couldn't hold idle at a stop sign. Would always stutter and die. Turns out it was a leak in a vacumn hose mount on the intake manifold. The hose was OK, but the mount point had a tiny crack which let in enough air to fool the idle sensor.
Good luck.
Good luck.
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