FB II

ok, so i got another carb off a running car. i put it on mine today and man, i'm having troubles. just as a few others are with their rebuilt carbs. the ONLY way i can get it cranked is to pour gas down the carb! then when it runs, it won't idle for **** and pops alot. BUT when i take it out for a drive, it DRIVES great! WTF! my friend says it may be the timing. is this possible? please help me guys, i've gone thru 2 carbs and alot of **** for this car. i don't want to have to sell it and my tII motor won't be done for a long while and this is my daily driver for now. thanks guys

wwilliam54

i hope you figure it out

im haveing the same prob

12abridgeport

I think that is exactly what you said, the timing. After i put a holley on my 12a, the timing got off quit a bit. Also make sure your idle screws are set right. If it's a holley it should be about one full turn out on each side.

Rx7carl

Are you sure you got it all clean inside when you rebuilt it? All the parts back in correctly? Whats the fuel level like in the windows?

wwilliam54

fuel levels are good here

and i set the timing right

no dice

Rx7carl

Really stupid question. Is your intake manifold gasket good? I mean leak free? Also whats your idle mixture screw set at?

wwilliam54

well i got a napa gasket
and my idel mixture is set a bit rich, just in case i have a vac leak

guess ill take the gasket out and try make another
(the holes are too small)
gotta put some 20mm freeze plugs in anyways

FB II

hey, you know those itty bitty holes that are on the plastic spacer of the manifold and on the bottom part of the carb? when i put the gasket on i didnt punch those holes out or anything so they were covered up. i just now thought of this, do those have a purpose? hahahha . there's like 4 or 5 of them on the passenger side of the carb i think. what do those do?

wwilliam54

up

FB II

up twice please, someone's gotta know.

"hey, you know those itty bitty holes that are on the plastic spacer of the manifold and on the bottom part of the carb? when i put the gasket on i didnt punch those holes out or anything so they were covered up. i just now thought of this, do those have a purpose? hahahha . there's like 4 or 5 of them on the passenger side of the carb i think. what do those do?"

if i can't figure this out soon, i will be forced to sell the car and go out and buy a new mobile unit with a warranty. the woman is getting pissed. :'( i have been trying to get ahold of rotorsports here but the guy doesn't call me back. i don't want to lose my REX!!! NOOOOOO!

Rx7carl

The kit shoulda come with new gaskets with the holes in it. Pull the carb off and remove the gaskets, your old ones should still be on the spacer. Try it and get back to us.

FB II

well, my gaskets didn't come with the holes in them and when i pulled my original carb off it had no gaskets at all. ODD I KNOW!!! that may have been my problem! AHHHHHHH, i didnt get to work on the car today, forkin crazy storms! hopefully tomorrow. i'm off work all day. i'll let you guys know, hope and pray for me!

wam

hey...if youd like bring that car to me and i mite be able to get it fixed for ya, you know i have plenty of parts to fix it!

AdrenalifeRX7

I still think your timing is off a bit

ioTus

iTrader: (5)

Things to check:

1) Timing
2) Idle screw adjust
3) Air/Fuel mixture (rich or lean, i forget which way is which)
4) Vacumn leak.

#4 can be a biggie, and if you still have the rats nest in there, good luck locating it!!! I suggest buying one of the colored silicone hose kits from JC Whitney Sport Compact for $30, plus 6 or so extra ft of 4mm tubing. this will ensure you have no vac leaks.

When checking for vac leaks, check the T junctions, as they are often the first things to physically deteriorate and corrode away.

vipernicus42

iTrader: (4)

I'm having pretty much the same problem. Mine can't idle worth crap, but if it's at high RPMs it runs just fine.

The spacer on mine didn't have a gasket on either the carb or the intake side... is it supposed to? I thought the "gasket" people were referring to *was* the plastic spacer.

I don't think it's the timing... at least I *hope* it's not.. I'll have to get a friend with a timing light to check it, but the problem is that I can't check timing at 3000rpm can I?

I wanna get mine running too, but it's not as urgent... This weekend I'm gonna reinstall the carb again, but if anyone has any suggestions, I'd love to hear 'em.

For everyone else having the problem: LOOK EVERYWHERE FOR VACUUM LEAKS.... I'm even replacing all my vacuum hoses while I'm in there, and doing a very particular job of it, just to MAKE SURE that it isn't a leak. I've been told vacuum leaks can cause these problems. I doubt it's timing in any case.

Damn this sucks. Wish me luck. Tomorrow is my day off and we have to hope for no storms... I'm going to install my new shutter valve, replace the hoses, put the carb back on, and use some zip ties and that non-drying silicon sealant on every damn vacuum connection and on the carb-to-spacer-to-manifold connection, since I don't have a gasket there, and I wanna be able to remove it at some point! I hope it was just that set of mating surfaces that was causing the vacuum leak, becuase other than that, I'm stumped!

Jon

ioTus

iTrader: (5)

Vipernicus42, i'm guessing you will fix your problem w/ those vacmun leaks.

A symptom of vacumn leaks: Car wont idle, but runs JUST FINE at higher RPM's.

MosesX605

The gaskets are basically integrated to the spacer, so if the new gaskets that came with the rebuild kit don't match up, don't use them, as you need to have all those vaccum ports clear for good running. Just bolt the carb to the spacer without the new gaskets. It'll work just fine AFAIK. I just did my carb, and I just tossed the gaskets that came with my kit, as they didn't match up at all to the spacer.

Your idle quality is dependent on a couple of things. Like everyone else has mentioned, vaccuum leaks will kill your idle quality. Make sure there aren't any leaks by spraying carb cleaner at various spots around the carb. If the engine speed decreases, you've found your leak.

If there aren't any leaks, turn your attention to the idle compensator. If the compensator is bad, or the hose is able to draw vaccuum, (see what I mean about vaccuum!) the car will not idle properly, or at all. Try plugging the hose to see if the idle gets better. If it does, you have found your culprit. The hose is the smaller of the two hoses found towards the rear of the aircleaner on the drivers side. There is a bi-metal spring on the inside of the aircleaner where the hose attaches.

If both of these check out, turn your attention to the idle speed and mixture screws. Your idle may be poor because of lean or rich conditions. The FSM has the procedure for setting the idle speed and mixture. The very generous Kevin Wright hosts an online copy of the '85 FSM at this address:

http://www.wankel.net/~krwright/files/1985_RX-7_FSM/

Anything I, or the more knowledgeable posters above haven't mentioned should be covered in the manual. Good luck.

Rx7carl

Matt is correct. The gaskets are integrated into the spacer.

FB II

well HOLY MOTHER OF GOD! i took the gaskets off and BAM! she cranks right up now. every time! WOOHOOOOOOOO!!!!!! it still won't idle right though, so i'm replacing every vaccum cap and line. i don't have much since i've removed the rats nest and all emissions. where's a common place that will leak? i've already replaced my Anti-After Burn hose, or can i cap that off too???

FB II

ok ok, i can not find this vaccum leak! BLAAAARRRRG!!! any special place to look?????

ioTus

iTrader: (5)

Everywhere. Take every hose off and replace it is my reccomendation..