listers

My 1979 SC has a problem starting when it has reached normal operating temp. If I get the temp up, stop for more then a few minutes I cannot start it until it has cooled down (usually a couple of hours) can anyone give me some advice. Russell

Chuck Harmon

This sounds like the famous starter going out symptom. I had a
problem with my 83SC not starting when hot... replaced the starter
never had the problem again.

listers

The starter appears to spin the motor just as quick when it is hot as it does when the motor is cold, I have tried push starting too (stuck late at night in far from home) with no success.

Alan Herod

As Chuck mentioned this is the famous SC heat soak starter problem if the starter does not spin the engine when the key is turned. I had this problem at WG four few years ago and trouble shot it by jumping the solenoid with a short piece of heavy guage wire. The starter motor ran great. I had the starter motor rebuilt with new brushes, bushings and a new solenoid for $75. Another SC had the exact same problem and was easily fixed for $600 (new high torque motor plus labor). Two ways to solve the problem. My youngest son demonstrated to his friends that my rebuilt starter had enough power to nearly drive through the garage door so high torque probably is not needed. No problems since.

The fact that your car will not push start is perplexing, not sure why that is unless something is also wrong with your ignition switch; but, that should have little to do whether the car is hot or cold. Other reasons not to start, fuel pump fuse starting to act up. Dead position on the ignition switch. Coil going bad?

pjc

Depends how 'hot' is 'hot' - if really hot this could be vapour lock where the engine gets so hot the fuel vaporises in the lines and has to cool down before liquid fuel gets through. Typical symptom is that the engine fires and dies over again. This is usually just an odd occurance rather than a regular happening however.

Possibly air/fuel mix, air leak etc?

PJC

Peter Zimmermann

Russell: There are a couple of places to start. In the engine compartment you will find a part called a fuel accumulator (next to the fuel filter), it's kind of Army green in color. I've replaced a number of them to fix a "hot, crank but won't start" problem. The second item to replace is the fuel pump, which has an internal valve that fails (which allows the fuel system to lose pressure during cool down). If your pump is 80K miles or more old replace it before the accumulator. The third item is much more rare, the internal coil inside the ignition distributor can develop a problem with the same symptom, but again, that's really rare. These are good places to start, let us know what happens.
Pete

gregg911

I agree with Peter, the accumulator has been the source of hot start problems for quite a few friends. I'd replace the accumulator, it's relatively cheap and real easy to replace. If thats not the problem, the pump valve may be bad and the pump may have to be replaced (not too difficult just a little dangerous). I did both on my SC and fixed the problem.

gregg911

p.s. DO NOT BUY A REBUILT PUMP!! the price may be attractive but buying another one and installing it twice isn't much fun. Pay the cash, do it once.

Mark Hald

The accumulator was the cause of the hot-start problem with my 77 3.0. Since it's not an inexpensive part, it's relatively easy to test with a hand-held vacuum pump before ordering a replacement.

Mark Wilson

My 79 had the same issue. Turned out to be the check valve in the fuel pump. The replacement check valve is NLA. I added an inline unit that fixed the problem - about $20.
Mark

listers

Thanks for the advice from all of you, this is a spectacular forum! I willl have a go at the accumulator and the fuel pump first. I live in a rural part of Zimbabwe so replacements are not going to be easy to come by. Can the accumulator be fixed?
Thanks
Russell

Mark Hald

The accumulator is a sealed metal unit. Attempting repair would require "extraordinary" effort with little chance of success.

Mine has three ports on it: an inlet, an outlet, and a drain back to the fuel return. With a hand-held vacuum pump, I applied vacuum to the inlet and put my thumb over the outlet. I could not pull any vacuum until I also covered the drain, which was indication that the diaphragm had failed. Similarly, one should be able to pull a vacuum on the drain port without covering the inlet & outlet. Mine wouldn't. I verified my assumptions by testing the new one in the same way.

As suggested by others, the check valve is another high failure item.

listers

thanks for the advice Mark, could this be why fuel pump sounds like it pumps all the time?

Russell

Peter Zimmermann

Russell: The pump running won't be related to the check valve issue. If your pump runs with the key on, but the engine off, something is wrong in your wiring. However, if the pump is really noisy one or both of its mounts may have failed, allowing it to contact the protection plate just below it. If you have to order a pump, and have it shipped, order two new mounts at the same time. They are less than $10 US each. Good luck with it!
Pete

Bill Gregory

If the starter spins, I would first examine the check valve for a fuel-related issue. Heat the engine up, clamp the fuel line coming out of the check valve on the fuel pump, wait 20 minutes, unclamp it, and if the engine starts right up, the check valve is suspect. It's replaceable without replacing the fuel pump. If fuel related, it could also still be the accumulator, as others pointed out.