1975 mercury 650 3 cylinder

jakestevens

Seaman
Joined
Feb 11, 2008
Messages
55
I wanted to share a story with everyone about my weekend the my 1975 Mercury. The original problem was no spark, back in march of 2008. I sent the trigger assembly off for re-manufacturing. Upon arrival I installed the trigger and had good spark. I still couldn't get the engine to start. I pulled the #1 spark plug and sprayed some fuel into the cylinder and re-installed the spark plug. The engine finally fired, but was very rough and wouldn't idle at all. Since I had the timing belt off, I went through the timing and synchronization procedure listed in the SELOC manual. I'm not very impressed with the SELOC manual, now that I realize what the timing and synchronization procedure is for.
After the T and S procedure the engine still ran rough and wouldn't idle. At this point I'm thinking there is something wrong with the fuel system. I checked the filter and it was ok. I disconnected the fuel line from the filter assembly to the carbs and pumped the bulb into a container. Then i noticed a leak at the bayonet, fuel connection from the fuel tank at the front of the engine. I drove to West marine and bought new connectors, it still leaked.
This time I bypassed the connector and connected the fuel tank straight to the fuel pump. The engine fired and ran great, it will idle now. I still have some carb tweaking to do but at least it will run long enough to do the adjustments.

So if your outboard is running rough, check for fuel leaks 1st!!

Thanks to all of you for helping with this repair, I retrieved lots of useful info. from this forum to get me through the repair.
 

dnappster

Recruit
Joined
May 24, 2012
Messages
1
Re: 1975 mercury 650 3 cylinder will my 1966 merc controls on this newer motor

Re: 1975 mercury 650 3 cylinder will my 1966 merc controls on this newer motor

been reading alot on this site and its been very helpful! Anyways i am now a member i have a 1966 Merc 650 and a 1975 merc 650> all the controls ignition everything is mounted on my boat for the 1966... My question is... can i use the controls, ignition for the 1975 merc 650?? the plugs are different but i can just cut and splice wires to match right??
 
Top