1985 75hp mercury cuts out when shifting in F and R.

[Mercs and such]

my motor will fire up ok but my electric choke broke so i have to manually do it. The motor if i shift it into forward without giving it any gas, just simply engaging it into forward, it will cut out. I have to shift it and floor it so it won't cut out. Same as reverse gear. sometimes actually until last week, it won't even stay idling when the gear shift is directly in neutral. I now have to press the throttle only and rev the motor up in neutral. the weird thing is it hesitates and kind of spurts it will idle then rev up about 300 rpm's and shoot out some blue smoke and it doesn't sound good when it idles. I really want to know why it is doing this and what i can do to repair it. I have not changed gear oil in a long time, the carburators have not been cleaned/ removed in a long time. and the choke solinoid will not engage when i push the key in.


thanks!!
Mercs and Such

 

[Fuzzytbay]

Re: 1985 75hp mercury cuts out when shifting in F and R.

Sounds like you need to do some service work to your motor. I'd start with the fuel system. That means fuel tank, hose's bulb fuel filter, fuel pumps, and carbs. After that, its time to find out why the choke doesn't work. is it the soliniod, or just the switch, or a bad ground, or broken positive lead wire.
Running a motor that needs service is just asking for a major brake down. If you fix the minor problems, with luck you will never have a major one.

 

["G"]

Re: 1985 75hp mercury cuts out when shifting in F and R.

Mercs and such-
You say the engine fires but won't run in gear. You haven't told us much about the last time you had the engine out. At any rate... the #1 item on any repair is the compression check. #2 is lower unit check. No sense in going further if either is shot. Now you need to decide on cost of fix.

The lower unit is not (typically) a cause for the engine not running correctly. If the engine runs well at idle and as you rev it up it sounds good (not missing etc) then we can make assumptions it MAY be OK. You know about assumptions right?

If you put the boat in the water, engine in gear and the motor dies you have put the engine under load. Avoid the load by putting the "muff's" on and running it on the hose. You should be listening for abnormal noise in the gearbox. If the engine quits when put into gear you might have an issue with the lower end. Shift the lower unit when not running and check it at the prop. You are looking for a solid lock up and a ratchet noise in the opposite direction (when in forward).

Dirty oil is not a cause for alarm, but water, a milky look, or even no oil would be cause for alarm. If there is sparkles in the oil you may have worn or broken parts. :

Now you said the engine is having trouble staying running in neutral which sort of tells us a story of where we might start. Most likely you have a fuel issue but it is possible that it is an electrical problem.

Either way your outboard needs some maintenance. Now is the time to "work it over" before you are stranded or in a bad spot on the water. Maintenance is ALWAYS cheaper than the alternatives and repercussions of not having a safe boat to ride in.

Make no assumptions on this safety rule.... there is NEVER any reason NOT to wear your PFD. I didn't need to tell you that because you ALWAYS wear one and require your riders to do the same. Right?