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Mercruiser 350 hot starts?

D

dremmick

New member
I have a 91 ski supreme with a 350 260hp mercruiser ingine. My mechanic installed a brand new edelbrock 1409 on my engine. It ran great right away. After about 20 mins of driving i let the boat sit for about 15 min and went to start it again and would not start. I could get it to start in neutral with increased RPM's but after a bit RPM's will start to fall and kill the engine. Once i put it in gear it kills instantly. If i let the engine sits for a few hrs and cool down it starts easy again, but once i drive it for a bit and shut off the engine for a few minutes and restart it, it gives me the same systems. So we performed a fuel pressure test, and compression test which were both good. spark plugs showed no signs of water. Enigne has pertronix ignitor, new distributor cap, rotor, sparkplugs, and sparkplug wires. So what could be going wrong when the engine is hot?​
 
When it will not start, you should have an old spark plug handy and remove a plug wire and use the old plug to test for spark. if there is spark, very carefully prime the motor with some starting ether to see if it is a fuel starvation problem.
 
A bad coil will give you a "Hot no start condition"
The coil will go open when hot and give you a weak spark. When it cools down, it will work again and test as good.
 
How can i test if the coil is bad? Aslo it will start in neutral with throttle foward but rpms start to fall and engine dies. How can i test the coil? Or should i just go buy a new one? Can i just get a eboxy filled coil for a chevy 350 at a local parts store?
 
I don't ever recommend a coil i ask that the person buy the coil that the manufacturer recommends.

You have spark at the plugs at the moment it happens ?

If no then it could be the coil.

Could be the pickup under the dist. cap maybe ?


Say you do have spark then it's another problem.

I'll wait for your reply.
 
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