140 evinrude overheating on one side

[dick reaves]

My 1977 140hp evinrude is overheating (buzzer actvated). I felt the discharge hoses and found that the left side, looking from the rear, was hot while the other hose was still cool. Also, is there a set of after market gages for this engine?

 

[Solittle]

Re: 140 evinrude overheating on one side

Your symptoms point to a sticking or stuck thermostat. I am replacing mine on my 87 110 for the same reason. The temp on one side was 200 degrees and 140 on the other read by temp gun.

 

[clint]

140 evinrude overheating on one side

I agree with the Vice Admiral with your thermostat is sticking. Replace them both and cruise with a clear head. Same thing happened to my 140 Rude. One side of engine hot and other cool. I change the thermostats and water pump at the same time. On the thermostats it is a little tricky with putting the housing back on and installing the thermostats. When was the last time you did a water pump?
Clint 8)

 

[emdsapmgr]

Re: 140 evinrude overheating on one side

In addition to checking the thermostat, have a look at the valve body in the thermostat housing. There should be two pinholes in it. Both holes are very small and can plug up. If the hole(s) plugs up, it will overheat on that side-even with a new thermostat. The hole permits hot water to get to the backside of the thermostat so that it will open.

 

[dick reaves]

Re: 140 evinrude overheating on one side

Thanks for the suggestions. Looking at the BRP parts catolog it seems to have only one thermostat. Is that correct? Why only one side overheating? Still seems like the easyest place to start. I assume I'll need all the gaskits that are shown.

 

[emdsapmgr]

Re: 140 evinrude overheating on one side

The 77 engine was the first year for two thermostats. The 76 and earlier V4 engines used only 1.

 

[Theoutdoorsman]

Re: 140 evinrude overheating on one side

Hey **** reaves............. maybe someone could come up with the Sierra part number on a kit for you. It's very possible you can locate the whole Thermostat Kit on ebay. I spent about $25 for mine I think. Yours might be the same. Might be worth a look-see!!!! Thought I'd mention it. Good luck to ya.................ALAN

 

[ezeke]

Re: 140 evinrude overheating on one side

While the diagram only shows one vernatherm, the parts list calls for two of each part.

 

[clint]

140 evinrude overheating on one side

The 140 hp has 2 thermostats, I replaced mine 2 weeks ago and it is a little bit of a task. You have to take the exhaust housing cover off to be able to easily access the bottom of motor where the thermostat housing is and buy a gasket replacement for housing. I think it was 8 bolts to remove. The thermostat Kit cost me around $25.00 for thec2 thermostats and gasket. It will run alot better with even temperture. Good Luck!
Clint 8)

 

[dick reaves]

Re: 140 evinrude overheating on one side

I was considering leaving the exhaust housing on and working around it (mighty tight). Has any one tried that? Replacing the water pump looks like more of a job than I ready for. Maybe after my repair manual comes in I'll try it. I really appreciate all the extra info everyone includes on thier posts. I have learned more from this site, including which manual to buy, than I'll probable learn from the manual.
Thanks

 

[clint]

140 evinrude overheating on one side

I tried for a long time on my 140 evinrude with housing cover on and I couldnt do it. It is not a big deal to remove and install the housing cover, you just have to purchase a $4.00 gasket. Believe me, it will be so much easier to reinstall the new thermostats. It is very very tricky because The 2 thermostats have to be lined up and the white tabs aligned with the springs and then holding it all together getting the bolts started. You need alot of room and alot of patience. I used a long screw driver to push against center of thermostat housing to keep it in a still position and started my bolts. Make sure to use gasket sealer. Good Luck!
Clint 8)

 

[ezeke]

Re: 140 evinrude overheating on one side

Uninvited minority opinion in case you might want to consider it.

A while back I got a little bored with the disassembly process described above. I drilled two one inch holes in the lower cowl using a Forstner machine bit and then connected the holes horizontally, top and bottom, with my Dremel. That has turned the process of changing thermostats into a 15 minute routine. I use a piece of fiberglass and a little two-part resin to cover the hole until the next time.

 

[Walker]

Re: 140 evinrude overheating on one side

To maybe improve on ezeke's method you can get rubber/plastic plugs to fill the holes. I don't know the proper name for them but older cars had them in the doors and sometimes in the firewalls.

 

[dick reaves]

Re: 140 evinrude overheating on one side

I got lucky, so far. I pulled the thermostat housing with everything in place. Yeah I know putting it back together is the charm. one of the t-stats is obviously broken. Also noted that the cork gaskets were between the t-stat and the exhaust housing adaptor, instead of between the valve body and the t-stat. Were they installed wrong? The parts blow up seems to show the gasket between the t-stat and the valve . ments welcome!
****

 

[dick reaves]

Re: 140 evinrude overheating on one side

I got lucky, so far. I pulled the thermostat housing with everything in place. Yeah I know putting it back together is the charm. one of the t-stats is obviously broken. Also noted that the cork gaskets were between the t-stat and the exhaust housing adaptor, instead of between the valve body and the t-stat. Were they installed wrong? The parts blow up seems to show the gasket between the t-stat and the valve . ments welcome!
****

 

[Solittle]

Re: 140 evinrude overheating on one side

On my 1987's you can get a tad more room by loosening the lower engine cover (the pan at the base of the engine). Rubber bands or tie wraps are helpful for holding the stuff together during assembly. I use sealer 1000 or equivalent sparingly for the gaskets.

 

[dick reaves]

Re: 140 evinrude overheating on one side

I took the rear exhaust cover off and still can't properly line up the t-stat for installation due to the lower motor cover. If I can't loosen the lower cover easily I may whack out a piece of it then glue it back in place after I'm finished as per Ezeke's post. Trama time to take a saw to my engine. For ease of future removal I'm considering anti-seize compound on the bolts and no gasket compound, or maybe just a little grease, on the gaskets. any comments welcome?