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Motor install problem....whats this noise

888 Views 8 Replies 6 Participants Last post by  Blue Thunder
Ok, I bought a 89 baja sunsport with a 4.3liter mercruiser in it. Guy thought the motor was blown so I pulled the motor out of it. Fired it up and decided I thought it was a freeze plug. Motor sounded good and ran solid it was just pumping water out the back like crazy. So I pulled the motor and sure enough one of the 3 freeze plugs was popped behind the flywheel. Got that fixed and put it all back together and noticed knocking noise which isnt constant. After turning the crank by hand we noticed its like every 1.5 turns. I think it is one of the following things.

1) I forgot to torque one of the bolts on the triangle peice that the input shaft fits into? (not sure the technical name for the peice)

2)The motor is not sitting completely straight. We tried to get it and straight as possible by measuring in from the sides off a marked off point but it could be to far forward or back. The shaft is in fine and seems to be no problems there.

I am pulling the motor again tomorrow night and would appreciate any input on the situation as this is my first boat motor pull (car mechanic!). If there is a trick to aligning these or knowing how to set it with the input shaft please share. I dont think the noise had anything to do with the shaft because I was running it in neutral when it made the noise. It almost has to be something flywheel related.
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You do have an alignment tool right? From reading Point 2 I dont think so :eek:
Use an alignment tool as said above. Probably first and easiest thing to check at this point. Gimble could be making noise due to mis-alignment.
your removing the drive again anyway so fire it up without the drive on. this will eliminate gimble ,ujoint and upper drive and you will know if the motor needs to come out again.

have someone hold the garden hose in the intake line to get water to the motor. or, i used to have a 12-18 inch piece of hose and stick it up in the intake. watch it doesnt blow out while running
No I sure dont! ha.....I measure up from the rear and made a mark and measured into the motor for side to side alignments and did the same on the rear.....Does anyone have a picture or knows who makes these things? Appreciate the help!
I got ahold of our local boat shop....I never even dropped the outdrive off of the boat. we just slid it forward onto the shaft and it fit....I hear I need to drop the outdrive to align this but Im kinda curious how this works....The motor is slotted on the mounts so when you are aligning the gimble does it require aligning the motor or are you aligning the outdrive? Local boat shop said if I drop the outdrive they can align it for $70.
lilemmick said:
Local boat shop said if I drop the outdrive they can align it for $70.
Sounds like a well spent $70 :D
It will cost you that much for the tool.
I bought my bar off of a member on the boards who makes them. "Bajacleveland" Very nice tool. I think I paid 50 or so bucks. + you have it forever then!
The triangular piece is called a coupler. You shouldn't run the engine again with the outdrive still on until it is properly aligned. You will ruin the coupler. I would definately remove the drive and run the engine without it but as said earlier make sure you have water pressure going into the engine (about 25psi max)because you will be running without the pump in the outdrive.
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