I am new to the forum and have a 35hp Johnson 1977 that overheated today. I was on the lake running top speed and noticed that the engine was losing power and slowing. When I looked back the tell tale or pee stream as I have heard it called was no longer streaming. I Immediately turned the engin off, took off the cowling and sure enough the engine was very hot. In fact I dropped some water on top of the engine and it boiled off immediately. I was towed in and sure the engine was destroyed.
When I got home I could turn the flywheel so I decided to pull the top spark plug. The plug looked good so I put the muffs on with water and the motor starts fine. At first there was no water coming out of tell tale, so I immediately shut it down. I took off the lower unit, looked at the impeller which looks ok (3years old). I used air to blow out the water intake tube and checked the supply hose from the block to outlet and found no blockage. I put the lower unit back on, started the motor and again it did not stream water. I tried it again to show my Dad the problem, but this time it streamed. On idle it is a little slow, but at half throttle in neutral with the muffs it is strong and the top of the engine is cool to the touch.
A little background. I have been trying to buy a new impeller for the last 3 weeks from my local dealer, but we finally determined that I have 77 motor with 78 foot so the impeller needed is different because between 77 and 78 they changed the impeller size/design. Once we figured that out I got the new impeller for a 78, but the slot/key mechanism is different than the one installed. It appears to be a type of slip key disign vs. a full cut slotted design. Anyway I was going to tackle that problem next week.
The engine paint is already gone so I can't tell if discolored. (a mouse built a nest on the engine a few years ago and his urine disolved the paint)
None of the wiring is melted.
The engine starts and sounds fine.
I run 50:1 Johnson/evinrude oil
Question:
Even though it sounds fine on the trailer could I still have damge and if so how would it show itself?
Has anyone ever run into this impeller issue for 77/78 Johnsons?
This boat/engine has much sentimental value to me. My Dad bought it new when I was 4years old and we have many memories of fishing together. I will keep it going as long as I can.
When I got home I could turn the flywheel so I decided to pull the top spark plug. The plug looked good so I put the muffs on with water and the motor starts fine. At first there was no water coming out of tell tale, so I immediately shut it down. I took off the lower unit, looked at the impeller which looks ok (3years old). I used air to blow out the water intake tube and checked the supply hose from the block to outlet and found no blockage. I put the lower unit back on, started the motor and again it did not stream water. I tried it again to show my Dad the problem, but this time it streamed. On idle it is a little slow, but at half throttle in neutral with the muffs it is strong and the top of the engine is cool to the touch.
A little background. I have been trying to buy a new impeller for the last 3 weeks from my local dealer, but we finally determined that I have 77 motor with 78 foot so the impeller needed is different because between 77 and 78 they changed the impeller size/design. Once we figured that out I got the new impeller for a 78, but the slot/key mechanism is different than the one installed. It appears to be a type of slip key disign vs. a full cut slotted design. Anyway I was going to tackle that problem next week.
The engine paint is already gone so I can't tell if discolored. (a mouse built a nest on the engine a few years ago and his urine disolved the paint)
None of the wiring is melted.
The engine starts and sounds fine.
I run 50:1 Johnson/evinrude oil
Question:
Even though it sounds fine on the trailer could I still have damge and if so how would it show itself?
Has anyone ever run into this impeller issue for 77/78 Johnsons?
This boat/engine has much sentimental value to me. My Dad bought it new when I was 4years old and we have many memories of fishing together. I will keep it going as long as I can.