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Hello, my name is***** will assist you today.
Is the motor out of the water currently?
OK, With the motor OFF, spin the prop while you watch the center of the prop shaft, it is bent?
When was the last time the gear oil was changed?
So it was good, no water?
Ia this a two stroke?
Alright, do you have the tools to do compression and spark on it?
This engine will start and run on 1 cyl. Hard to tell that it is not. But it will be lacking power on top end.
Sounds good. You can normally rent one from an auto pats store. A spark checker as well.
Make sure that you have the throttle opened as far is it will go with the engine in neutral before starting the test.
Ok, How does the engine oil look?
Does it vibrate even in Neutral or just in gear?
Will it also vibrate if you run it on the hose?
Well you could put it on a flusher, you just need a special one and remove the prop.
Did you check that gear oil recently? Like in the last few days or just the last time you changed it?
The compression spec is no more than 55 LBS at cranking due to the compression release.
We are trying to see if the vibration is just the prop or something else.
While you have it in the water, use a good insulated pliers and remove one plug wire at a time to see if both cylinders are firing the same.
Have you recently hit bottom of had the engine stop very suddenly?
Replace a timing belt?
If the motor was not out of time, that would do it. Was the belt changed, or has it been off?
Has it ever run hot or run with out oil?
Do you idle the engine allot?
Are the spark plug tips really black?
Ok, did you buy or rent that compression gauge. I misquoted the spec.
Ok,I need for you to do it again. Make sure that the throttle is as open as you can get it in Neutral. Crank the engine over until the gauge maxes out.
Sounds good. It should be around over 150.
Would you please poist the serial number on the engine?
Thanks. Been looking around, but I cant find anything either. I will grab the manual tomorrow from the shop. It has the spec in it and I will let you know what it is.
I have the manual here with me. the compression should be 60 MAX. This is due to the compression release on the cam. When doing a leakdown test, the result will be off, unless the valve cover is removed the the compression release deactivated.
Also, when you did the test, did you use the hose from your compression tester?
Before you did the leakdown test. Did you remove the valve from the hose?
Did you also use a ratchet to roll the engine over to the compression stroke of the cylinder being tested?
Ok, that is a compression test. How did you do the leakdown test?
Now I understand. What you actually tested was the holding of the valve in the end of the hose of your compression gauge. A leakdown test requires that you put compressed air to a special gauge set, then put that pressure into the cylinder, roll the engine over using the flywheel nut to TDC of the cylinder being tested. The percentage of leakdown is shown on your test tool. This article describes how to do it.
The test was to see if each cylinder was functioning correctly.
With the running without the gear case, that has eliminated it. Remove the pull starter, see if you can wiggle the flywheel at all. Also try and lift it up. This will check the bearings around the crank.
Then remove the plugs, slowly turn the flywheel by hand. Insert a screwdriver into the cylinder and turn the flywheel until the piston is at the top of the stroke. UIsing the screw driver, press in on the piston, there should be no movement at all.