1986 40hp Johnson buzzer on with water running

ba_50 · Oct 22, 2006

We just got this motor and drove it about 4 miles to the dock including some high speed running. No problem at that point.

Tonight we idled it for 200 yards and the buzzer came on. We went back to the dock and the motor was too hot to touch. The water was coming out of the Phole.

The only thing I can think of is not enough oil, but I always measure it and it was smoking when we started it. I will hook up another tank just in case.

Could there be another reason? I don't see any thermostat on the back in case it got stuck. Thanks.

Walker · Oct 22, 2006

Re: 1986 40hp Johnson buzzer on with water running

My bet is a weak water pump. Just because its pissing doesn't necessarily mean its getting enough water.

rickdb1boat · Oct 22, 2006

Re: 1986 40hp Johnson buzzer on with water running

Yep. If you just got it, change the pump for good measure and check the T-stat too...#12 is the Stat:

freddyray21 · Oct 23, 2006

Re: 1986 40hp Johnson buzzer on with water running

I would think thermostat, but agree change the pump. It's not that difficult to do and good insurance and piece of mind to know when it was last changed.

ba_50 · Oct 23, 2006

Re: 1986 40hp Johnson buzzer on with water running

I got the thermostat apart and it wasn't stuck and not much too it. Just a plug and spring as far as I can tell. No buildup of salt or sand. Guess I'll drop the lower unit next.

JUSTINTIME · Oct 24, 2006

Re: 1986 40hp Johnson buzzer on with water running

test t-stat in hot water to make sure it opens up
check temp sensor also same way but with an ohm meter
could be water pump also, if u do replace it look at the housing, replace if that looks worn out

freddyray21 · Oct 24, 2006

Re: 1986 40hp Johnson buzzer on with water running

check and see if you have't sucked something up in the tubes. Had a motor once had a mud dobbers nest in it. Could be it got sucked in the tubes clogging them

ba_50 · Oct 24, 2006

Re: 1986 40hp Johnson buzzer on with water running

The thermostat was missing. I can't figure out how to get the LU to drop down. All the bolts are out. It looks like it disconnects just back of the carburator. Looks complicated.

Solittle · Oct 24, 2006

Re: 1986 40hp Johnson buzzer on with water running

It is not complicated unless you are not comfortable around the typical tools in a garage. You should buy the OMC shop manual as it gives detailed instructions and pictures for most everything. As fo dropping the lower unit my bet is that you need to disconnect the shift rod which is either at the base of the carb or accessed via a plate on the side of the mid section.

ba_50 · Oct 26, 2006

Re: 1986 40hp Johnson buzzer on with water running

This time I took out the bolt under the carburator and the unit still won't come off. The manuals don't help either. Bummer.

tashasdaddy · Oct 26, 2006

Re: 1986 40hp Johnson buzzer on with water running

on some there is a bolt under the trim fin .

ba_50 · Oct 26, 2006

Re: 1986 40hp Johnson buzzer on with water running

There doesn't appear to be anything holding it as it has dropped down about 2 inches.

ba_50 · Oct 28, 2006

Re: 1986 40hp Johnson buzzer on with water running

There is a small black pin on the side of the bellcrank coupler but ther isn't anything to get a hold of, if that's it.

imported_bboat · Oct 28, 2006

Re: 1986 40hp Johnson buzzer on with water running

I've got a 1985 40hp so it might be similar (maybe exactly the same as yours) and I recently experienced the exact same problem. The first tiem that I got the boat and ran the engine on muffs it ran fine. Then when I took it out on the water, it overheated (buzzer and all)even though it appeared that there was plenty of water coming out of the pee hole.

I dropped the lower unit and replaced the impeller and cleaned the water pump housing up, and now it runs great...I was kind of amazed in the difference of how much more water was coming out with the new impeller...so I'd definitely start there. My local library had a copy of the repair manual, so you can save some money that way too.

There was a total of 6 bolts on the lower unit, four obvious ones around the base and then two by the trim fin (one holding the trim fin on). I also had to disconnect the shift rod, which is just one bolt located in the bottom of the engine pan. If you haven't disconnected the shift rod, then that's prob why you can't get it to drop any farther.

Good luck.

ba_50 · Oct 28, 2006

Re: 1986 40hp Johnson buzzer on with water running

bboat,

That is what I'm trying to figure out, how to disonnect the shift rod. There is one bolt that goes straight in from the front which I believe keeps the shift rod from moving.

I took it all the way out and it wouldn't drop down. I was told a screw should go in from the starter side but there isn't anything but a small pin in the end of the coupling. There doesn't seem to be anyway to unscrew it. It doesn't look like a bolt head broke off either.

I looked at another motor today, but not sure about the year. It had a bolt going into the side.

Thanks for the reply

imported_bboat · Oct 29, 2006

Re: 1986 40hp Johnson buzzer on with water running

First, take a flash light and shine it down into the bottom of the engine pan and have someone put it in-and-out of gear so you can see the last point where the linkage moves. Then, if you shine a light down in the very bottom of the engine pan there on the starter side, you should be able to see a little bit of the shift-rod sticking up and where it attaches. It's held on by one bolt (which is sort of difficult to get to by the way, I found removing the starter really helped) that kind of looks over-sized which may make you think that it couldn't be it.

But yeh taking the starter off will make it a lot easier to see, and once you find where the shift-rod is sticking up through the bottom of the engine pan you should be able to see which bolt needs taken off.

Good luck man.

ba_50 · Oct 31, 2006

Re: 1986 40hp Johnson buzzer on with water running

Does this disconnect bolt go itn to silver clamp with the front bolt going ito it only on the side? It is possible the bolt head broke off but the steel is black, which I would think should be silver.

Walker · Oct 31, 2006

Re: 1986 40hp Johnson buzzer on with water running

Pull the bottom carb off so you can see whats going on down there.
Look on the starboard side shift linkage and see if there is a hitch pin stuck through the linkage right at the motor. If so, pull that pin and push the linkage toward the port side of the motor.

ba_50 · Nov 1, 2006

Re: 1986 40hp Johnson buzzer on with water running

Walker,

That was the right method this time. Seems like they are all different. Right now the impeller is soaking in PB Blaster due to rust. I'm glad a solution. Thanks. Bob

ba_50 · Nov 2, 2006

Re: 1986 40hp Johnson buzzer on with water running

Well, I'm not sure what the trouble is now.

The motor has been sitting for 2 years so the impeller has a small amount of set it but looks almost new.

I can pump water up the tube and out the pee hole.

There was a pressure relief valve but no thermostat. (I will put one in)

The head head gasket isn't torn

The water jacket wasn't leaking that I know of.

Yet the buzzer went off and the motor was hot.

Any ideas?

1986 40hp Johnson buzzer on with water running

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