1973 OVER HEATED... What would you do?

[morrocco mole]

I have a 1973 135 HP Evinrude that impeller just fell apart which caused the motor over heat. I had the compression checked and out of the 4 cylinders on the motor 1 cylinder was very low. Should I replace the impeller or should I scrap the one thing? I know the cost of another power head is about $1300.00 bucks. Something that I don't have laying around right now. The mechanic said that the impeller would fix the pump but he was not sure if it would run and if it does. He was sure it wouldn't run for long. Should I give a go or let it go?

 

[rolmops]

Re: 1973 OVER HEATED... What would you do?

Time to hit e-bay.

 

[Sal G]

Re: 1973 OVER HEATED... What would you do?

What is "very low"?<br />Give us the readings.<br />Trouble with buying a used <br />engine is sometimes your buying someone elses<br />headache! Because of your $ situation-<br />I'd give the new impeller thing a shot.<br />That is not really an expensive fix.

 

[Sal G]

Re: 1973 OVER HEATED... What would you do?

On second thought- get a second opinion from a mechanic. I don't believe in throwing good money away, but maybe this engine could last longer<br />than what was projected. Just don't take any <br />"extended" trips if you know what I mean.<br />I do hear of guys running on 3 out of 4 cylinders.<br />The ends should justify the means.<br />Good luck.

 

[DJ]

Re: 1973 OVER HEATED... What would you do?

Low compression can be caused by several things.<br /><br />Pop off both heads and have a look. That will tell you if it's worth fixing. The head gaskets should be replaced anyway after a severe overheat.

 

[morrocco mole]

Re: 1973 OVER HEATED... What would you do?

I will found out what the numbers were and I will try to take the heads off to see what’s going on. I have managed to do one auto rebuild myself and have replaced alternators, starters, valve cover gaskets and things like that before but this is something different right? So should I take the heads off myself or take it somewhere to have them look at it? I feel I can do it but having outboard knowledge is another thing.

 

[morrocco mole]

Re: 1973 OVER HEATED... What would you do?

DO you guys think it is better to just buy the impeller or to buy the kit? I am not sure of just what is in the kit but it costs $84.50. I thought the impeller cost $35.00?

 

[The Marine Doctor]

Re: 1973 OVER HEATED... What would you do?

Generally the wear plate and housing are in need of being changed at the same time the impeller is.<br /><br />On these older engines anyway <br /><br />TMD

 

[morrocco mole]

Re: 1973 OVER HEATED... What would you do?

Okay, then I will pick one of these up today then.

 

[Sal G]

Re: 1973 OVER HEATED... What would you do?

I know that removing my 85 140 VRO heads were a snap! Go for it!

 

[morrocco mole]

Re: 1973 OVER HEATED... What would you do?

I will give it a try. I have the boat back a the mechanic did not put the lower unit back on becuase his there was no need. I have all the hardware to put it back together but I need to find my manual or just have him install the impeller and put it all back together again. Then I can take off the heads and give it a try.

 

[morrocco mole]

Re: 1973 OVER HEATED... What would you do?

I found out after doing a test or two that the cylinders that were giving low compression readings have a blown head gasket. I notice that when I checked the spark plugs that there were signs of water on the plugs. So now it is time to change the Head Gaskets... I sure hope that this will fix the old girl and get her going again?

 

[morrocco mole]

Re: 1973 OVER HEATED... What would you do?

I pulled the heads and the haed gasket was blown so after I replace the gasket, take a compression read, then I will let you guys know how I make out.

 

[morrocco mole]

Re: 1973 OVER HEATED... What would you do?

I took a long look at the cylinder sleeves and I did not see any marks on the walls and the piston heads looked fine as well. I did not notice a play in the pistons either. Everything as far as the pistons seems to me to be tight. I did not have a torque wrench last night but I have one today and I will post the results after I put her back together and turn her on.

 

[morrocco mole]

Re: 1973 OVER HEATED... What would you do?

Well, here it goes…. First I change the head gasket on the side with low compression. Started the motor up and it sound great! Then after about 3 - 4 minutes or so, I check the compression and it was great too! Then I pull the head off the other side and replace that gasket. The compression on this side was fine from the beginning. After another 3 – 4 minutes run I checked the compression and all was fine too. It starts on a dime and I was not sure about the water pump or impeller. So I call the mechanic on Sunday and he looked at the motor and started it up. That’s when he made a comment of “did you rebuild this power head or what!” joking around. He said this is the best he has ever heard this motor run ever, wow! He checked the compression and said that it was closed to perfect. He then said, take it to the river and have some fun with it. So I went to Bowers Beach and gave it a try. It gave me some trouble starting at the ramp for some reason but after many try’s it finally held a good idle. It was like it had some bad gas or something. Anyway we took her out and it ran faster then she ever had before. I gained about 3.5 mph in speed. It also started right up as soon as I hit the key. This it has never done on the water but at home it would. Thanks to all of you guys and GOD for sending you to my rescue. I would say I am pretty luck and very happy right now. I cannot thank all of you enough. Your advice was right on the mark and when I had mentioned a blown head gasket to the mechanic he was surprised that’s all the motor need was the gaskets replaced. Thanks Morrocco Mole!