Won't start when hot

[singing pilgram]

1996 Volvo Penta 4.3 GL SX Cobra Serial # 3868413T0361686 First running runs good, shut off and won't start when the engine is hot. Replaced fuel pump, fuel filter, cap and rotor, module and coil, runs great, but still will not start when it is hot.

 

[Bob1944]

Re: Won't start when hot

I had this problem with another engine and it was just a bad battery. It was really the battery that was getting hot and cells shorted out when it was hot. Might also make sure all the connectors are clean. Might have the starter motor checked too. Sometimes something is causing too much drag on the engine when hot.

 

[351 OMC]

Re: Won't start when hot

I'm having kinda the same problem. My 2000 5.7 merc inboard just started this thing of shutting down after about 30 min. I replaced the coil twice because it was getting so hot you couldn't touch it. The engine would not re-start until I would cool the coil down with ice to try and make it home and then it would run fine for another 30 min and do the same thing. I am trouble shooting now for what is making the coil hot. Maybe we can find the problem. I live 2 hours from where I keep my boat and it has to be in the water to test it. ( I have run it for a hour on the rack and can't duplicate it there). I'll keep tabs on your thread and let you know if I find anything. I'm curious about the battery issue. I run two batts on both on the selector all the time. If one was bad maybe that could cause some problem that I haven't even considered. I am thinking of replacing the distributer next. My thread is called Bad Coil? in case you want to watch that one. Good luck

 

[singing pilgram]

Re: Won't start when hot

Battery and starter are fine, turns over and fires then shuts down. Tried changing the coil to a new coil, and still will not stay running when hot. When cold it is running great, when hot it is running great, it just won't restart, it just fires and dies.

 

[Bob1944]

Re: Won't start when hot

Hmmmm, I was pondering this and it occured to me that when a wire gets hot it is shorted out, or pos an pos are going throught the wire from both ends. something is shorting out the coil. Could it be in the ignition switch or someplace between the ignition switch and the coil?

 

[singing pilgram]

Re: Won't start when hot

This is a tuff one... will run all day perfect, just don't turn the key off... turn that key off when its hot and... cranks, fires up, then dies. I'm gonna try to get it hot and when it wont start check at coil for voltage.

 

[singing pilgram]

Re: Won't start when hot

Checked at coil for power, getting voltage. I have new cap and rotor. Checked coil wire to dist. with ohms looks ok. Does anyone know if there is a momentary kill on controller? I've heard that when you shift into gear you get a moment , short pause, to protect the trans. any coments? Is there such a switch?

 

[singing pilgram]

Re: Won't start when hot

Someone said there is a second oil send switch?? could possibly shut down engine if diffective anyone know?

 

[Don S]

Re: Won't start when hot

cranks, fires up, then dies.

When it does fire up, how long does it run before it quits again.

 

[singing pilgram]

Re: Won't start when hot

Keeps running fine...just when it get real hot won't restart..turns over fires but wont run.

 

[singing pilgram]

Re: Won't start when hot

I'd like to add that yesterday it was cooler outside and when I ran the boat it went fine.. all day started and stoped restarted no problem. Seems to be just when it's real hot out side, like the day I needed Sea
tow ran fine then when I stoped for a hour would not run fired, turned over but would not stay running.

 

[Don S]

Re: Won't start when hot

Sounds like a vapor lock. If it's getting real hot in your engine compartment, you might want to leave the blower on to circulate some aire and cool things off. Engine compartment may need some more air vents.
Do you let it idle and cool down for a couple of minutes before you shut it off (when you have the starting problems)?

 

[singing pilgram]

Re: Won't start when hot

No I don't think we do. But when we got the Seatow we were just coming into the dock so we weren't run fast. But it did have time to heat up.

 

[singing pilgram]

Re: Won't start when hot

OK Just bringing Things up to date. 'Bout 70 degrees today 9AM boat starts right up warm up to temp 150 run at idell 5min. boat is in water. So cooling is fine. We know it's getting gas 89 octane in tank, fresh. Turn off key,let heat build 5mins. Boat will not start. Now we have new fuel pump, gas lines are fine. carb getting gas. When we push throdlle gas is entering carb, We have even dripped gas into carb. So we beleive carb is getting gas into the barrels. On the Electric side we used spark tester to see if spark is stronge. Doesn't seem to be a good strong spark. We have tested to see 12v from key to distributor, from dis. to coil(tryed a new coil, no difference). New module( still no difference) New cap and rotor(as I said previous It needed new cap and rotor) So now again,When It's cool say in the morning This boat runs like never before. Just don't shut it off. Sometimes it will start but more then likely it wont. Yesterday I let it sit after not starting 6hrs. still wouldn't start. But the next morning it started right up. Tryed cooling down the Dist. coil Volvo Penta#3854001 Started twice after doing so ,Third time would not. For $45bucks I'll try a new one. Little work but it may do the trick....Any thoughts?????