86 MerCruiser runs fine... then heats up, dies, won't start

[baker274]

Ok. Three of the last four times on the water the following has occurred:

She'll run great for a good 30-45 minutes. We'll turn off the engine for 20-45 minutes, and then when I try to restart, it doesn't sound right. If I get it started, it's only for a few minutes. Then it dies, and won't restart. It gets VERY hot as well. Well over 175 degrees. Once we get home and it cools down, it starts again.

Last weekend this same thing happened. However, I noticed that the secondary (clear) fuel line running from the fuel pump to the carborator was clogged with a bunch of thick green goo. I don't understand why this happened, but when I removed the line and tried to turn it over -- it started right up.

Questions:
1. What is the green goo.
2. Did disconnecting this line (and running without one) really make the difference in my engine turning over?
3. Why is my engine getting so hot.

Has anyone seen this line clogged before?

HELP!

 

[twocycle]

Re: 86 MerCruiser runs fine... then heats up, dies, won't start

First of all chances are removing that line really did nothing at all as it is only a way to vent the back side of the diaphram. If and when the diaphram would fail and allow fuel on the back side it would be contained in the hose and the translucent hose is a visual indicator. On our old cars and trucks a mechanical pump would just have a hole there and the fuel would run out, but in a boat we don't want fuel and fumes in the bilge so they use that hose so it can vent that fuel and those fumes back into the carb. That green gunk is very common and is the residue from the vapors that are emmitted from the fuel pump. Those vapors do contain some solids and they form what you see in that hose. If it's that bad it would probably be best to just replace the hose. It tends to get very stiff and hard and is much easier to just replace anyway. Any Mercruiser dealer should have it.
Since you didn't give anymore info regarding which Merc Engine you have I'm gonna take a wild stab at the overheating part - Ninety percent of the time a bad sea water pump in the lower unit is the cause of stern drive engines overheating. Don't start it again until you've had it replaced!

Happy boating!
John
Owner/Operator
UB&M

 

[JB]

Re: 86 MerCruiser runs fine... then heats up, dies, won't start

Hi, Baker.

Welcome to iboats.

Your engine is not an outboard and is not identified.

Go to the Mercruiser Forum, Tell us what engine you have and repost your question.

Good luck.

 

[victorc1]

Re: 86 MerCruiser runs fine... then heats up, dies, won't start

regarding that i dont know what type of motor it is but i have a 96 mercrruser 3.0 and i would say check your impeller and termostat before changing your water pump. since most of these motors are like car motors and they are running in salt water the termostat freeze's.

 

[JB]

Re: 86 MerCruiser runs fine... then heats up, dies, won't start

Three year old thread, Victor. Please check dates before you resurrect dead threads.