M880 hot starting problem.

[RichM882]

Hi all.
My Dodge is not as happy with hot starts as she is with cold starting. When she has been running for a while and got up to running temperature if you stop her she takes a fair amount of cranking before she will fire up again. If you leave her to cool for a good period or say overnight then she will start first turn again. Has anyone else on the forum had this problem. She has never failed to start but it would be good to sort it out.

 

[steelandcanvas]

Isolate the ignition coil off the intake manifold...worked for me with some small-block Chevys I built back in the day.

 

[Noman]

So the electrical system on theses things was not the best. It was mostly from the fifties and they just keep adding things on as need. So it cant really handle the loads that are created by the alternator. So your problem could be a few things related to this. First I would just replace the ballast resistor if you have not tried this already. It is the porcelain thing on the drivers side firewall. It job is to reduce the voltage from 12 to 8 volts so the coil wont burn up and is a common failure point. Most people keep a spare in the glove box just in case. The ballast resistor has two path ways a start and a run. During start it will give the coil a full 12 volts for a hotter spark and a run position of 8 volt. So if the start side is failing add a little heat and the resistor will no longer work, but cool it back down and every thing is golden. Plus they are 5 dollars and 5 minuets. Beyond that you should look in to a few wiring updates. Such as the alternator firewall bypass and any place there is a pin connection which are all corroded now trust me. These things could lead to voltage problems, failure of voltage sensitive parts (ballast resistor) and fire(seriously do the alternator wire).

 

[WVCB]

I was having the same problem awhile back with my W200 and it finally just quit going down the road one day. I figured out it was the ignition switch; replaced it and all was good. I don't know why a hot start problem would be caused by a faulty switch. Maybe insufficient voltage? Cured the problem anyway.

 

[Noman]

I was having the same problem awhile back with my W200 and it finally just quit going down the road one day. I figured out it was the ignition switch; replaced it and all was good. I don't know why a hot start problem would be caused by a faulty switch. Maybe insufficient voltage? Cured the problem anyway.

Doesn't matter now, but just so you know. There were no relays in the wiring system, the just ran the hot wire for any key on systems straight through the ignition switch. This set up can generate a lot of heat, add a little age and the switch resistance goes up very quickly. I would guess that was why you had a replace the switch.

RichM882 - If it not your ballast resistor then as WVCB said the ignition switch would be a good thing to look at. It is not a hard job, but you will need some small snap ring pliers and a steering wheel puller. Beyond that all you have left is the ignition module and coil. Or I suppose a bad piece of wire, but that is unlikely and very hard to find. If you don't have a multimeter get one. You don't need a real nice one just some thing that will give you a few numbers. Here in the States $30-$40 get you one that is good enough for this kind of work. I don't image that they will be to different on your side of the world.

Long term it might not be a bad idea to put a relay in the engine compartment to reduce the loading on that switch. That is next on my list but haven’t found the time and that is something you want to plan out a little so the ignition system still works after.

 

[Bob H]

It takes air, fuel & spark to fire. Replacing parts before determining which one is missing isn't very efficient.

for me the hot start issue has been you need to give it a little peddle (fuel) to fire it up.