1980 evinrude 140 overheating one side

[fishdog4449]

hey guys,
Just finished rebuilding an evinrude 140 crossflow v4. The powerhead on the engine was scored and needed a hone, I had a spare powerhead with good compression. I gave it a light hone and new rings and used all the carbs, fuel pump, and electronics from the original engine. I started it up and after about 2-3 minutes got an overheat alarm. I shut it down and the port head (from behind the engine, looking forward) was very hot to the touch, the stbd was slightly warm. I checked the t-stats they were fine. I also disconnected the water hoses running from the block to the tstat housing and almost the same amount of water was flowing out of each head. Next, checked the plugs. All on the stbd side were fine, the top plug on the port side was clean, like water intrusion. Now for my question, what could be going on? I'm hoping someone says something like the head could be cracked and all I have to do is put a new head on (I have several extras). The engine had all new head. exhaust, and water gaskets.
thanks in advance!

 

[fishdog4449]

Re: 1980 evinrude 140 overheating one side

Forgot to mention that the water coming out of the head on the port (hot) side was hot to the touch while the water on the stbd side was lukewarm.

 

[ezeke]

Re: 1980 evinrude 140 overheating one side

Did you replace the water passage deflectors?

Bleed holes clear in the thermostat valve body?

 

[fishdog4449]

Re: 1980 evinrude 140 overheating one side

I cleaned the bleed holes, replaced water deflectors, cleaned water passages etc. The head gasket is brand new.

I ran the motor again today and the hot head ran much much cooler. I could hold my hand on it for 10-15 seconds at least if not indefinitly. The water exiting the head was ~ 110 degrees. This was on the hose at about 500-600 rpm, in gear, in a bucket. The cooling water on the hose was @ 80 degrees. The other head was lukewarm and cooling water likewise.

Something else that I didn't think could affect heat this much...but the 'hot' side has one new piston and new rings on both pistons. The other side has the original rings. I honed each cylinder just enough to get the cross hatch back. I added some extra oil for the rings to break it it's about 40:1 right now. Could the extra friction be bringing up the cylinder temps?

 

[ezeke]

Re: 1980 evinrude 140 overheating one side

Actually, you should be running 25:1 until you finish the break-in.

If you have a factory service manual follow the break-in instructions for a new engine, usually found in section titled General Information or General Service Information.

 

[kenmyfam]

Re: 1980 evinrude 140 overheating one side

At 110 degrees and 80 degrees neither side is actually overheating.
Are you trying it out on the muffs or in the water ???

 

[fishdog4449]

Re: 1980 evinrude 140 overheating one side

This was on muffs. Thanks for the heads up ezeke the seloc didn't say much about break ins I'll get the factory manual.

 

[itsaboattime]

Re: 1980 evinrude 140 overheating one side

I had the same thing less than a week ago.

http://forums.iboats.com/showthread.php?t=415082

When out on the water ALOT more water runs through the system than on muffs. It will cool off.

 

[kenmyfam]

Re: 1980 evinrude 140 overheating one side

I have had one side hotter than the other on the muffs although not overheating. The lake will give you the real picture.

 

[fishdog4449]

Re: 1980 evinrude 140 overheating one side

it ran perfect at the lake heads were the same temperature warm to the touch not too hot. had a fuel issue that ended up being fuel filter/separator clogged and bad primer bulb.