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1983 50 HP 4 cylinder Mercury, a few questions

JasRam

Contributing Member
I just picked up a 1983 50 hp 4 cyl Mercury. I bought it knowing that it didn't run, I checked compression and got 105 in each cylinder, which I thought was decent. He said that he let it sit for two years and that his local marina said that the carbs were probably gummed up from sitting, he didn't want to pay the 120.00 per hour to find the problem or have the carbs cleaned.. I just got it tonight so I havent done anything else at this point. I'm wondering what I should do first? it seems lik cleaning the carbs is the obvious thing, but is there anything else i should check?

Also, it has power tilt and trim- when I was looking at it to buy, we coundn't get the trim to go up, it would only go down after we used the "trailer" button to go up. I got it home and lowered it all the way down with the trim/tilt, I was then able to raise it until it sort of came to a soft stop and appeared to be somewhat level. This is my first oat with tilt/trim so I have no idea how this is supposed to work. Does it not need to tilt up much?
 
Everything in the fuel system needs to be checked and cleaned or repaired/replaced, fuel hoses can come apart on the inside also. Would replace the water pump impeller also, they get stiff with age.
I'm going to have to ask for some more detail on which tilt switches work and how high the engine comes up. The engine obviously needs to come up far enough to not drag the boat ramp and the highway when trailering the boat. You have probably seen pictures of boats with the engine tilted to get some idea, similar to manual tilt without the effort. If the tilt pump works but the engine doesn't rise far then check the tilt fluid level.
 
Everything in the fuel system needs to be checked and cleaned or repaired/replaced, fuel hoses can come apart on the inside also. Would replace the water pump impeller also, they get stiff with age.
I'm going to have to ask for some more detail on which tilt switches work and how high the engine comes up. The engine obviously needs to come up far enough to not drag the boat ramp and the highway when trailering the boat. You have probably seen pictures of boats with the engine tilted to get some idea, similar to manual tilt without the effort. If the tilt pump works but the engine doesn't rise far then check the tilt fluid level.

Thanks for the response. I dug into the carbs today and put new gaskets in each one as well as in each fuel pump. They didn't look too bad other than a bit of debris on one of the fuel pump filters. I found that the wires coming from the rectifier are completely corroded, they are actually dust inside of a plastic wiring jacket... I'm thinking this could be one of the reasons for it not starting? I'm wondering if I can just replace the wires if the rectifier is good? These are the only wires on the motor that look like this.

One other question, the corroded wires are the two that go up to a place under the flywheel (i think it's a flywheel.. it has notches and timing marks. I can't tell waht it goes into but I feel like if I could get to that, I'd be able to add new wires. I'll check on tilt/ trim issue tomorrow.
 
Thanks for the response. I dug into the carbs today and put new gaskets in each one as well as in each fuel pump. They didn't look too bad other than a bit of debris on one of the fuel pump filters. I found that the wires coming from the rectifier are completely corroded, they are actually dust inside of a plastic wiring jacket... I'm thinking this could be one of the reasons for it not starting? I'm wondering if I can just replace the wires if the rectifier is good? These are the only wires on the motor that look like this.

One other question, the corroded wires are the two that go up to a place under the flywheel (i think it's a flywheel.. it has notches and timing marks. I can't tell waht it goes into but I feel like if I could get to that, I'd be able to add new wires. I'll check on tilt/ trim issue tomorrow.

I took the flywheel off to beter see the wires on the trigger, one is corroded all the way into the base of the trigger.I was hoping I could splice into some good wire but it's impossible. Just ordered a new stator and trigger.
 
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