fbatman

ok so Ive just amassed a few questions posted one thread, so here they are:

so the car takes some coaxing to get it to start, its an 85 GS, its got a Mikuni, RB headers, exhaust through a high flo cat, no accessories, battery is good, alt is good, starter seems fine (?), it just takes a few cranks to get it going(see description of starting below, but omit the part where it doesnt catch),

once it does start it drives fine if its floored or under 3K, starts stumbling at partial throttle right around 3k, but if i floor it it goes away (what could that be? it cant be the idle circuit transitioning if it goes away when floored could it?)

Heres the kicker: after the car has been driven and been running at OT(180F) and i cut it, if i happen to come back in under a half an hour or so it wont start- its like it has to cool down (under 140F)in order to start again...any ideas? While starting, the starter will wind the motor up *almost* until it catches but it just wont, even if i blip the throttle...imaginations please- tro tro tro tru tru tru tritritririririri...repeat.

as always, thanks in advance...
zach

ps- Doc, flushed refilled, new thermo, and overheating issues are gone, Thanks!!

Rx-7Doctor

iTrader: (13)

Good to here you got the overheating issue resolved. I worry more about that then the regular driveability issues.

Need to know when the symptons started. Has the Mikuni been on for awhile or just put on? Also what else besides cooling system work was recently done?

fbatman

likewise, that was big hurdle number one, the mikuni was just put on, but it didnt do this before- i drove it up to tennessee from atlanta about two hours solid with no hiccupps, although starting was still questionable. but the mikuni is the only carb thats been on the car since its been driven, (bought it not running, wrestled with a 525 road demon jr 4bbl...no deal...) i just recently serviced the oil pedestal, thats the only thing thats been done to the motor really other than the cooling system...

Rx-7Doctor

iTrader: (13)

I would check for vacuum leaks at the intake manifold and where the carb bolts to the manifold.

Also check the float level and inspect for debris in the jets. Might have some sediment buildup.

It's easy enough to take the cover off of the jet housing and pull the jet block assembly to inspect the jets. Also you will be able to see if there is any foreign material floating around.

fbatman

Awesome!! will give it a look-see tomorrow morning and report back, thanks!! actually thinking about it, i did just put some pantyhose as a temporary filter til the real one gets here...not sure if that would affect anything, but that is one thing that changed in between? ill run it tomorrow w/o those on it and see if it still does the same.

Rx-7Doctor

iTrader: (13)

That pantyhose can cause all of your symptons, you are better off without a filter than having it on there. Use the pantyhose for an emergency fan belt.

fbatman

sorry, got distracted. some crazy college boys done raided ma house. but really? hm...will def try it now w/o it on there, going to pick up the sp in t minus 7 hours!!!nap time...

fbatman

ok, without the panty hose im back to smooth acceleration, which is oh so nice! but the starting is still questionable, it still does the same kind of wind up deal, im getting better at getting it to catch, but what could be causing this? could it just be my starter is old and doesnt like me? ok in all seriousness...if it was going out wouldnt it get progressively slower instead of winding up and not catching?

Rx-7Doctor

iTrader: (13)

If you are stating that the starter is spinning but not engaging the flywheel to turn it then the bendix drive or over running portion of the starter is bad. Time to replace the starter. Also inspect the teeth on the flywheel for any damage.

fbatman

ill take a look at the flywheel but its not like its not engaging, its engaging and spinning, but it just takes forever for it to crank...i'm probably going to replace the starter when I swap the motors out anyway just because its probably the original starter, i was just curious if it could be something else not starter related.

Rx-7Doctor

iTrader: (13)

This is why you threw me. The portion of winding up and not catching. It should be stated that the engine cranks but takes awhile to "Fire" or "Start".

Excessive cranking without starting could be attributed to vacuum leaks, improper Air/Fuel mixture.

Worn plugs (partially fouled). Failing ignitor, etc.............
You need to check for fire to both leading and trailing sides when you are having this problem to eliminate the possibility of a bad ignitor.