Symptoms of bad main relay, but i have a carb

[conozo]

I have the symptoms of bad main relay, but i have a carb.
Symptoms

Hard to start when warm, takes two attempts



First attempt will start the engine for a half a second then dies


Second attempt takes longer 1-4 seconds of cranking and foot slightly on gas pedal


First 30 seconds to 2 minutes of car running idle and throttle is not steady and consistent

If bad, hard to accelerate for the first two minutes

Causes of symptoms

Above 70 degrees, sunny, no wind


Car engine is completely warmed up, then turned off



Car must sit there between 10 minutes and 1.5 hours to have problems again


If car sits there for longer, then there are no problems

I believe that when the car sits there after it is off in hot weather, sunny, and no wind, the engine bay heats up to a temperature that is higher than regular driving and operating temperature therefore causing something in the carburetor to malfunction until it cools down with cooler air from having the engine on for a couple minutes. Also could it be that i need to resolder my Fuel pump cut off relay?

[conozo]

bump

[2oodoor]

How hot is it outside when this happens?
Besides checking the usual ign tune up parts, the carb could be flooding due to the charcoal canister not breathing, so the carb bowl venting is not happening, gas could be "boiling" over so to speak. Check the site glass for the bowl too, before you start but after you have failed an attempt.

Of course there are a few other things that could do this, par the the carb ehh
fuel cutoff solenoid could be stuck or have debris in the pintle, reply after you check some things...

[Vanilla Sky]

I had this problem, and it turned out to be my coil. Only happened when it was hot outside. Reasonably hard to start when cold, no start when hot.

[2oodoor]

I had this problem, and it turned out to be my coil. Only happened when it was hot outside. Reasonably hard to start when cold, no start when hot.
definatley a good thing to check before you go chasing gremlinss

[russiankid]

How hot is it outside when this happens?
Besides checking the usual ign tune up parts, the carb could be flooding due to the charcoal canister not breathing, so the carb bowl venting is not happening, gas could be "boiling" over so to speak. Check the site glass for the bowl too, before you start but after you have failed an attempt.
Of course there are a few other things that could do this, par the the carb ehh
fuel cutoff solenoid could be stuck or have debris in the pintle, reply after you check some things...
This is the problem i had. I had a problem with the vent cut off valve, and when hot it would take a few cranks to get it started.

[conozo]

I had this problem, and it turned out to be my coil. Only happened when it was hot outside. Reasonably hard to start when cold, no start when hot.
I checked my coil today and here is what i found.
The shop manual says "resistance will vary with the coil temperature, specifications are at 70 degrees F"
-I ran the test with a cold engine and outside temperatures at 82 degrees F

Test #1
-Shop Manual: Primary winding resistance between A and D: 1,215 - 1,485 ohms
-My results: 190 ohms

Test #2
-Shop Manual: Secondary Winding resistance between A and secondary winding terminal: 11,074 - 11,526 ohms
-My results: 12,000 ohms

Test #3
-Shop manual: Resistance between B and D terminals" 2,200 ohms
-My results: 2,190 ohms

Overall results: I guess my primary winding is pretty bad. So i might upgrade to a MSD coil sometime.

[conozo]

So i finally replaced my ignition coil, put in new spark plug wires, checked my spark plugs, and cleaned out my 1 year old distributor. No difference. Its still hard to start when the engine is pretty warm and warm outside.

[w261w261]

So the carbed cars have no main relay box behind the coin drawer like the f.i. cars do?

[MessyHonda]

So the carbed cars have no main relay box behind the coin drawer like the f.i. cars do?



they have like a fuel cut off chip...i remember i had to replace that on mydx with a junkyard unit and it did not help...i found out that the fuel pump was causing the problems.

[2oodoor]

kinda sound like a loose booster venturi, or other internal carb problem that is letting gas leak out of the bowl while it is sitting. The solenoid on the back of the carb also could let gas go onto engine. Does it seem flooded when it does this , or does it smell kind of ozone when it starts (which would mean opposite)

[conozo]

When its hard to start, the tach will jump up very quickly as if it started then die. It jumps just high enough to disengage the starter so i have to try to start it again. The second time i start i crank for a few seconds while holding the gas pedal down slightly. Then after it starts there is alot of unburnt gas smell for a minute untill the idle returns back to normal. The car has absolutely no symptoms of anything when its warmed up. I also want to note that not very often (about 1 out of 30 starts) I start it, back up, then put it in drive and press the gas pedal to accelerate, but the rpms dip for a second then it goes. Im not sure if this sounds like its flooding.

I checked the booster venturi and it is not loose. I am going to check the fuel cut off relay today.

[2oodoor]

So i finally replaced my ignition coil, put in new spark plug wires, checked my spark plugs, and cleaned out my 1 year old distributor. No difference. Its still hard to start when the engine is pretty warm and warm outside.

this is confusing now

[POS carb]

you need to check your choke lever operation, check for vacuum leaks

since you mention it is temperature specific I would recommend checking the choke to make sure it works. Once your car has sat for a few hours or overnight, remove the air cleaner lid and look down the screen, the choke should be opened. press the accelerator in once and let go, the choke should snap shut. Turn on the engine and make sure the choke is opening after a minute of running. Try to hold it open with a screwdriver and note if it idles better.

once the engine is running use carb cleaner to check for leaks. listen for hissing sounds, spray around the base of the carb and intake manifold, on the thermovalves (rear of the manifold, also one by the thermostat) and if the idle raises you found the leak. If you can get a vacuum gauge you should have 15-22 inHg at idle.

[POS carb]

also there are some air bleeds in the airbox for hot weather, maybe one is broken or stuck open. check them for excessive leak with the carb cleaner. you could also plug the vacuum lines if you are feeling lucky

[conozo]

I just talked to a real mechanic today who knows these carbs well. I forget the part he mentioned, but basically it is flooding causing the hard starts. And he said over time, that extra gas gets into the cylinders and drys out the oil on the piston rings causing it to burn oil. He mentioned a way to tell if the car is flooding is to check for a gasoline smell in the oil. So the fix is to replace the gaskets in the carb. He quoted me at $230 to do that. I will keep everyone posted on what the final solution is.

[POS carb]

buy a brand new weber 32/36 carb for $ 300, have an adapter plate cut and avoid the guesswork

[2oodoor]

buy a brand new weber 32/36 carb for $ 300, have an adapter plate cut and avoid the guesswork

yeah, no kidding, your troubles will be few... and conzo:huh: I think I resent the wording of the remark "I talked to a real mechanic"
I have certifications in engine performance and driveability from ASC, Ford Motor co, and GM.

[conozo]

I think I resent the wording of the remark "I talked to a real mechanic"
I have certifications in engine performance and driveability from ASC, Ford Motor co, and GM.

I say that because i have been trying to find someone in my town that will work on our carbs for several years now and this is the only person who hasnt told me they wont work on it. So to me a real mechanic is someone who will fix my carb and not just tell me to get a new car. The honda dealership here wont even try to fix it.

[2oodoor]

haa haaa... yep I know what you mean, it was hard to find anybody who wanted to spend time to work on Any Mazda, Toyota, Honda, Nissaan, Mitsubodboo ... carbs even when they were relattively new. The problem was TIME, It takes a lot of time to tinker with these and to find a fair price to charge custiomers was difficult, that, and the chances were always high for a return of the problems. So I feel safe in saying the most learned Asian carb were the ones actually owned by mechanics, those were the guys who were able to add that skill to offer to the public. Most shops even in the eightys would sell the weber conversions to paying customers, it simply was the best value for all concerned, and a sure guaruntee the problems would no return.

[lostforawhile]

check out importcarbs.com for what that guy is charging you can get a carb returned to factory new condition with a good warranty, and it's been tested. this is the best deal i've found anywhere,and he's been in the import carb buisness for a long time. right now a completly overhauled carb is 229,thats also been tested on a running engine,and adjusted. plus he says anything over 200 is free shipping.

[2oodoor]

excellant link Lostforawhile!!

It is still a gamble for our cars though because of all the carb controls not on the carb itself which can cause bookoo problems.

[conozo]

Ok, im looking at the 32/38 weber carb. I have two questions, i live in a cold climate (northern indiana) how will the weber effect my warm up times. How will it be different or the same from my stock carb. Secondly, does anyone have any actual HP or torque numbers that show the amount of improvement with this weber.