1978 35 HP Evinrude - Normal Operating Temp?

[chuckp]

Hello Guys,

I purchased a 1978 35 HP long shaft tiller steer manual start Evinrude (model no. 35853R) a few weeks ago - first time I ran it I noticed how hot the water output was. The tell tale had a good output and the exhaust housing outlet had good water output at throttle while underway although some of the water steamed and was too hot to the touch.

I put a water pump kit in it and replaced the thermostat and water jacket gasket (old stat was plugged up and non-functional) after cleaning surface crude (it was not too heavy) out of the water jacket passages. Water coming out of the tell tale is still strong and not too hot while the exhaust water flows well underway but is still too hot to the touch. It does not seem to be steaming as much but still goes up to 160 deg at the top of the crankcase with a infrared temp gauge.

So is 160 deg too hot for the motor? The paint shows discoloration on the top, left hand side of the crankcase and head as pictured below. Should I pull the head and check the passages and water deflectors next or check behind the exhaust covers? I have an OEM manual on order - does anyone know what the torque should be on the head and exhaust cover bolts?

Thanks!

Chuck

 

[jbjennings]

Re: 1978 35 HP Evinrude - Normal Operating Temp?

I think 140-160 degrees is o.k. The only other thing you haven't covered would be the exhaust cover gaskets. They will go bad if the engine is overheated in the past, and can let exhaust gases enter the water jackets. Not saying you have that problem, just thought I'd mention it.
You haven't mentioned where you were located, but I can tell you that if the water temp. is high, that could be causing the water exiting your engine to be hot. If you live in the south, I'll bet that's why it's so hot. If the water temp. is below 70 degrees and it's that hot, I'd suspect bad exhaust cover gaskets.
I'm not sure of the torque specs.
Good luck,
JBJ

 

[Haffiman]

Re: 1978 35 HP Evinrude - Normal Operating Temp?

If still the original head gasket, pull the head and change both gasket AND water deflectors. The deflectors are the ones directing the flow in the cylinder and too often neglected. If they are not sealing and directing properly you will have hot spots in the cylinder. The thermostat is about 150F, and you will burn your hand at that temperature.

 

[chuckp]

Re: 1978 35 HP Evinrude - Normal Operating Temp?

Thanks for the info guys, I was thinking that 160 deg is on the high side of what the temp should be for this motor - I had one of these Evinrude 35 hp motors new in 1979 and do not remember the water being so hot coming out of the exhaust outlet. I don't think the exhaust water on any of the smaller outboards I've owned or been around were this hot. I live in south Alabama so it is pretty hot right now although the river we run the motor in has a cold water spring feeding it.

I'm leaning towards doing the head gasket and deflectors first and then the exhaust covers/gaskets if that does not help - wish I had bought an entire power head gasket kit now instead of getting just the water jacket gasket!

Chuck