1964 Evinrude 75HP overheating help please

[seedpws]

I have a 1964 evinrude 75hp v4 motor on my 17 foot boat. I was on the lake and the boat was not plaining out. I had alot of weight on the boat so I thought it might just be taking awhile to plain. The all of a sudden the motor shut down like someone hit a kill switch. I felt the motor and it was very hot. (Even the cover was too hot to touch for 2 seconds.) The boat starts and idles well. I have replaced the impeller even though the old one looked fine trying to fix the overheating. I took it on the lake again and it did the same thing.

On the v4 75hp this is two tubes coming from the head to a housing that contains a single vernatherm control. I removed the two hoses coming from the head to see how much water flow was coming out. Looking from the back of the motor where the spark plugs are the left side has a full stream of water shooting out and only water. On the right side there is some water and it looks like alot of exhaust. It is the white smoke that is normal coming from the exhaust but should it be coming from this water outlet also? From running it in a trash can with the tubes off it feels like the side with the exhaust coming out of it too is alot hotter than the other side.

Is it normal for exhaust to be coming out with the water on only the one side and not the other? What could be causing this to happen? Please give me ideas on how to fix it. The impeller was installed correctly and so was the water pipes as one is short than the other and it’s impossible to mix them up. Thanks for any help you can provide.
Steve

 

[R.Johnson]

Re: 1964 Evinrude 75HP overheating help please

On an engine that age, you need a complete water pump. Impellor, plate , housing. You will need to check the head, and exhaust cover gaskets' also. You have an exhaust leak into the cooling passage's

 

[xtraham]

Re: 1964 Evinrude 75HP overheating help please

I think you have 2 thermostats in that motor it might be possible that 1 is not opening, after getting as hot as you described I would suggest checking the compression, do not sweat, the pro's here will get you up and running. good luck

 

[Silvertip]

Re: 1964 Evinrude 75HP overheating help please

Start with a compression check. Serious overheat often results in a blown head gasket. If a gasket is blown, might as well replace both sides. That will give you a chance to check cylinder walls for scoring. If all appears ok, replace the heads and try running without the thermostats TEMPORARILY. If the engine stays cool, replace the stats. Go boating.

 

[seedpws]

Re: 1964 Evinrude 75HP overheating help please

There is just the one vernatherm in this motor right? And could a blown head gasket cause the overheating because the impeller was fine. I replaced it just incase and the motor can find the first 5 times out this year but when we had 5 people on the boat it did it and also after the water pump was replaced I went out by myself and it also did it.

right side getting hotter and not much water coming out.

right side getting hotter and not much water coming out.

Three movies showing what it looks like from the back running. One move also shows how the left side water flows out even after its shut off but the right side doesn't. Let me know what to do from here. Thanks (quicktime movie format)
http://seedpws.zftp.com/DSCN1783.MOV
http://seedpws.zftp.com/DSCN1785.MOV
http://seedpws.zftp.com/DSCN1781.MOV

 

[seedpws]

Re: 1964 Evinrude 75HP overheating help please

I just compession tested all 4 cylenders and all are right around 100 besides the #1 on the right side (the side that is over heating) The #1 is at 60psi. Also when I took the spark plug it looked wet and none of the others where wet. What should I do next?

 

[xtraham]

Re: 1964 Evinrude 75HP overheating help please

pull the head inspect the cyl head gasket and internal parts for damage, if your lucky you just blew the gasket. good luck.A motor run's on an alternative sorce of power, an engine makes it's own.

 

[seedpws]

Re: 1964 Evinrude 75HP overheating help please

the metal in the last two pics was in where that water goes around the head. Not sure where it came from or if it has anything to do with anything.

 

[seedpws]

Re: 1964 Evinrude 75HP overheating help please

I am not sure what I am looking for. I see that the top cylinder is blacker than the bottom. The top is 60psi and the rest are 100psi or so. From these pics can you see anything wrong?

 

[seedpws]

Re: 1964 Evinrude 75HP overheating help please

Here is the top part of the head. The gasket was cracked next to where the spark plug hole is. Also it was very dirty with sand like stuff. Here are pics.

 

[xtraham]

Re: 1964 Evinrude 75HP overheating help please

looks to me as if the top cyl had been leaking combustion, but looks like the bottom cyl is getting water, where the pieces of gasket or missing was that stuck to the block or just gone? i cant tell the condition of the cyl walls from the pic's are the walls smooth? or do they have scratches cut in them?

 

[seedpws]

Re: 1964 Evinrude 75HP overheating help please

The cyl of the walls are smooth. The top one with the less compression has more oil on the walls than the lower one. The head gasket was all in one piece and doesn't look bad as in cracked or any holes in it. It does have some wear on the upper one as you can see in the pic.

 

[seedpws]

Re: 1964 Evinrude 75HP overheating help please

shows the water hole with damage where water could prob enter.

 

[xtraham]

Re: 1964 Evinrude 75HP overheating help please

yes, thats the part of the gasket i was asking was it stuck to the head? or was it just gone? if the rest of it is not present on the head thats the problem...

 

[seedpws]

Re: 1964 Evinrude 75HP overheating help please

Yes there was nothing stuck to the head. Is that maybe why the compression is so low on the one? If I replace just the head gasket and the other gasket on top do you think it will fix the compression and the overheating?

 

[xtraham]

Re: 1964 Evinrude 75HP overheating help please

thats is without a doubt a problem, personaly seeing the condition of the outter plate salt/sand i would recommend replacing both head gaskets, clean and back flush everything, check heads to see if they need to be milled. (machine shop)

 

[jimmbo]

Re: 1964 Evinrude 75HP overheating help please

Try a new gasket, if the numbers improve, that was the problem. If not the the rings might be sticking, in which a good de-carboning is in order. As for the thermostat, that engine only has one. It also has a pressure valve in the stat housing.
If there is less than normal water flow and pressure, exhaust can backflow into the cooling syatem

 

[Evinrude Boater]

Re: 1964 Evinrude 75HP overheating help please

Steve,
Do you have the overheating light hooked up in your boat? I noticed the overheat sensor in your photos but I sense you were unaware of the overheating situation until the engine spoke up. Looks like someone doesn't like lifting the motor in shallow water and it's been sucking in lots of sediment. That's rough on a water pump too. That's why you should buy the water pump rebuild kit instead of just a new impeller. The plate can get quite worn down pumping sand. It looks nice and smooth because its been wet sanded but it looses suction after a while. I have a '64 Evinrude 75hp too. Mine is a Speedifour, is your's a Selectric?

 

[seedpws]

Re: 1964 Evinrude 75HP overheating help please

Ok I found the parts needed I believe. I wanted to replace the vernatherm just in case. I can't seem to find the part number to it. On the bottom of it it has 04 01 143. Anyone know where to look it up?
18-2873 V-4 Cylinder Cover Starboard 18-2873 3.99 3.99
18-2872 V-4 Cylinder Cover port 18-2872 3.10 3.10
18-2959 Head Gasket 18-2959
I anyone know the part number for the water pump kit or plate and everything needed besides the impeller? I would buy that too and do itall to HOPE my boat runs and lets me get on the lake for the best walleye and perch session yet! Thanks for all the help everyone so far.
Oh and the boat has a heat "ball" type thing that says hot but don't think it works. I need to look into what I have to do to put a light or something like that on the boat instead.

 

[xtraham]

Re: 1964 Evinrude 75HP overheating help please

try here....http://www.iboats.com/bbboard/bbBoard.cgi?a=redirect;url=http://www.marineengine.com