89 Johnson thermostat

[jakers4777]

89 Johnson thermostat

Thanks to the tips and info I've received here on the forum I have managed to rebuild my carbs, put on all new fuel lines, uninstall the VRO and install a standard fuel ****.<br /> Got one question. I'm not satisfied with the amount of water coming out of the pisser. I put in a water pump kit last year and the flow looked good. I want to back flush and check the thermostat but: the Johnson service manual I have does not show the location of the stat. I'm assuming(and hoping) that it is behind the large nut just above the upper spark plug, right?<br /> Also, what are the opening and closing temps supposed to be? Check it like an auto stat with a thermometer and hot water?

 

[ledgefinder]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

What size motor, jakers?

 

[Walker]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

That's exactly where its at. One on each side.

 

[Walker]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

Oops, maybe only one if its not a V motor. Also, I believe OMC upgraded some thermostats since your motor was built, get new ones, don't mess with testing the old ones.

 

[jakers4777]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

My mistake!!! 89 40 hp Johnson, Thought I had put the year and model in the post heading.<br /> Same question, is the thermostat under the large nut just above the upper spark plug?

 

[ob]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

Jakers, here's a diagram that shows a breakdown of the thermostat assy.<br /> thermostat assy.

 

[Mufasa]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

The overboard indicator should be re-routed to the top of the exhaust cover if not already done. Also if you are testing it on a hose, flushing adapter, it will not look the same.

 

[jakers4777]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

OK, thanks for the help. I think I have it now. The diagram helped. <br /> And yes, I was using a flusher in both cases.<br /> Is there any kind of rubber lube that I can try to get into the impeller? I think I saw a post here that said using Ivory soap during the back flush might help lube and soften the impeller if it had been setting up for a while.<br /> On another subject, looking at my service manual, I see the reference to checking the head temp with melt sticks. Radio shack has an infrared thermometer that is pretty accurate. It should work as well as the sticks as well as getting the temp at several different points on the engine. It's also handy for getting the water surface temp when fishing.

 

[Mufasa]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

Yes the infared temp guns work well. I have not had my digital pyrometer out in quite a while.

 

[Sailormannj]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

What are those infrared temp things called if I go into a store to buy one? Are they temp guages? Really work?

 

[xp150]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

Jakers If I read your post correctly you replaced the VRO with a standard fuel pump.I was told a standard pump would not pump enough fuel. I was told to unhook the oil side of the pump and let it pump the gas (premix 50-1).Hope this helps.

 

[jakers4777]

Re: 89 Johnson thermostat

Re: 89 Johnson thermostat

The infrared thermometer at Radio Shack is part number 22-325. It lists for $49.99 but comes up on sale once in awhile(I paid $39.99).I have a commercial pyrometer that is used to check temps in copier and the 'Shack model will read within one or two degrees of it.<br /> On the fuel pump question, the pump I ordered and installed is supposed to work ok on a 40hp commercial so I can't see why it won't work on my rec. model.<br /> If you can lead me to any documentation on the subject I would surely appreciate it, hate to get on the water and find out.(runs fine on the muff),thats just at idle though.