Evinrude Mechanic

[Cattail]

Who is the best Evinrude Mechanic in the mid-shore area? I need someone who can sniff out a problem that most can't find.

[Lone Ranger]

Whats the problem?

[Cattail]

2000 model year 200 hp FICHT (530 hours) - port engine high temp alarm activates after reaching cruising speed of 3800 - 4000 rpm's. Usual repairs done - pump , thermostats, impeller, blow-off valve. Also heads removed and water deflectors changed, temp sensor changed, engine flushed and cleaned.

Lower right side cylinder heats up to +/- 200 degrees while all other cylinders running 130 - 145 degrees when alarm sounds. There is some scoring on the lower right cylinder.

Current mechanic suggests replacing engines. No one suggests replacing powerhead. I just want problem diagnosed so I can make an informed decision.

[Screamin Sunbird]

We had a similar problem with a 100hp motor. It would overheat if you got over 4000rpms. It turned out to be a scored cylinder from stuck rings. The carbon had built up behind the rings and they were scoring the cylinder and causing excess heat. If you remove the heads and look at the cylinder you will be able to see scoring on the cylinder walls.

Sounds like you have the same problem and a replacement or rebuild is in your future.

Sorry for the bad news.

Mike

[Cattail]

Thanks for the input. A friend of mine talked to an old-timer who worked on outboards and he said the same thing. Planning on digging deeper into the engine next week. Will keep you posted on what we find.

[Cattail]

Today we checked for a water flow blockage throughout the system. Did find that the hot water drain on the starboard side was partially blocked by plastic from a piece of the thermostat cap. It appears my dealer when replacing the thermostats in 3/04 broke off part of the cap when removing it and pieces fell in the hole. Last year when checking for the overheat problem we noticed pieces of the threaded insert in the thermostat spring.

Anyway we flushed the powerhead while it was off and the flow was perfect. Also checked the lower unit for flow and it was O.K. after removing the plastic. Hope to replace powerhead tomorrow but won't be able to water test until Wednesday. Will let you know the results.

My concern now is how much damage was caused by the overheating and the slightly scored cylinder?

[Cattail]

Hopefuly problem solved. Water tested today and while running at 4000 rpm's for quite some distance the temperatures in all cylinders ran between 125 - 140 degrees. Leak down test showed 8% in the subject cylinder while all others showed 4 - 6%. Compression showed 135 both tops and middle and 130 both bottoms. Scoring in the one cylinder must be minimal.

[Bob H.]

Most auto speed shops carry temp sticks in assorted ranges. Good for quickly locating hot spots. I've got a few sticks ranging from 160F to 250F.