Engine won't idle on the water

[gallows]

The engine idles OK on earmuffs but as soon as it goes in the water it won?t idle. Warms up for a couple of minutes then dies. It will restart immediately run for about 10 to 15 seconds then die again and will continue to do this. It runs OK at higher speed on the water. On returning home and I put the earmuffs back on it still will not idle, just runs for about 15 seconds then dies. A day or two later it will then run OK on earmuffs but only until it goes back in the water. Looks to me like water is getting into the engine somewhere to be causing this problem. The problem goes away after the boat has been out of the water for a couple of days. It recently had a new thermostat fitted. I very recently purchased the boat and it has always had this problem. 1994 Evinrude 70hp oil injected.

 

[tashasdaddy]

Re: Engine won't idle on the water

it sounds like you have a low speed problem, what are you idle rpms, in the water and in gear? i idle speed stop screw, has to be set and fine tuned in the water and in gear. or you have a low speed carb jet problem. do you have spark on all 3 cylinders, when it is acting up. what is your compression on all 3?

 

[gallows]

Re: Engine won't idle on the water

When I had the engine checked out prior to purchase the engineer said the compression was good on all 3. Idle speed on the water is quite fast, actually faster than I would like for trolling. It just will not idle on the water after about 15 seconds it dies. But will immediately start up and run again for a short time then stop again and keep doing this. When I get home it wont idle on the earmuffs either until about a day or two later. Then it will run fine until I put it one the water again.

 

[tashasdaddy]

Re: Engine won't idle on the water

"When I had the engine checked out prior to purchase the engineer said" that was then, this is now. things change.

 

[gallows]

Re: Engine won't idle on the water

Finally fixed the problem. I took the boat to a marine engineer who suspected a fuel problem and stripped down the carbs, cleaned and rebuilt them. It didn't solve the problem. He then checked the fuel pump pressure. All Ok, but it didn't fix the problem. I then took the boat home and did some investigating myself. I began to think it was electrical and started checking the simple things first. Plugs all OK, but replaced anyway. Then I took a l look at the powerpack. It has three leads each going to the low tension side of each coil. The top and middle ones were fine, but when I removed the bottom rubber cup and pulled off the push on connector it was very badly corroded with a white powdery deposit all over the connector. I cleaned it off and the problem was gone. The engine now runs sweet and performs perfectly at idle. I think at some time previously before I bought the boat, salt water must have got into the engine housing and got into the low tension terminal of the lower coil and caused the very bad corrosion which must have affected the spark on the bottom cylinder at low revs. Learned a good lesson here. Always check the simple things first!

 

[Randyg123]

Re: Engine won't idle on the water

Good job.

Since it was working well with the muffs on, I was going to suggest you just run it in the water with your earmuffs on

 

[gallows]

Re: Engine won't idle on the water

What a great idea, I never thought of that!!

 

[wavrider]

Re: Engine won't idle on the water

I think someone tried that one before. Made for a short trip but no damage.