Overheat adventure on 1985 Universal M12

[jssailem]

Put Teflon tape on the thread I imagine.

No. Most temp sensor’s are electrically grounded by being threaded into the engine block. The Teflon tape will insulate the sensor and you’ll wonder why it is not working.

The threads are NPT and generally produce a sealed attachment.

 

[odaydokay]

Boy oh boy does that ever make sense. Many thanks.

 

[eherlihy]

better source than Depco is Pumpsandpartsonline.com - Cardinal Pump

 

[odaydokay]

Thanks for that info. Do they rebuild as well?

 

[eherlihy]

Thanks for that info. Do they rebuild as well?

I wasn't aware that Depco would rebuild a pump for you. Cardinal pump sells the kits. See Rubber Impeller Pumps

 

[JoeWhite]

I can easily say that I am an expert when it comes to rebuilding the oberdorfer raw water pump.
Visit here

Oberdorfer Seals Replacement | Sail La Vie

mei1970.org

And view both album Images to get an idea of how to rebuild. I used steering wheel puller to remove and reinsert the seals.
Later I discovered identical seals for about $14.00 each that was encased in neoprene. It could be inserted with just a finger. I had my doubts that it would last very long. It has now been 42 hours with no leaks. To rebuild, you only need to replace the 2 seals when they start to leak.
PM me if you need more info.

 

[odaydokay]

Thank you very much, Joe, much appreciate!

 

[Stu Jackson]

I can easily say that I am an expert when it comes to rebuilding the oberdorfer raw water pump.
Visit here

Me, too!

Oberdorfer Pump Rebuild 101 - http://c34.org/bbs/index.php/topic,6766.0.html

 

[odaydokay]

The saga continues. Rebuilt pump installed and new T-stat and sender also. Took a run down the channel and same thing, 200 degrees nearly. should have burped it so that will be next along with checking heat exchanger mung. Both end caps can be removed. Mr. Cool wants $24 just for the UPS of a replacement end cap so wonder if I need that to get a new rubber seal. Awful how some companies mark up their shipping cost.

 

[Stu Jackson]

99% of the time the end caps are just fine. You're right, get or make new seals, less expensive to make 'em out of gasket material.

a replacement end cap so wonder if I need that to get a new rubber seal.

 

[Woodworks1]

I went out last week and it was cooling fine then about 10 to 15 minutes out and it started overheating. So i shut it off and started yanking hoses loose and the one before the impeller was old and soft like the inside had separate from the outer cover.
The water at the seacock seemed to be running slow at first when I pulled the hose off it. Most likely both were the problem low flow making higher negative pressure on the line and collapsing hose under the add vacuum.

 

[odaydokay]

I have now decided that it’s best to wait until the boat comes out of the water before open up both ends of the HX. The risk of damaging something so the engine won’t start such as sharing off an end cap bolt would create real problems in my getting to the yard for hauling. I’m not gaining much for a week or 10 days time and I may as well just wait. Does anybody have any experience about whether these cap bolts tend to share off or not typically?

 

[JoeWhite]

I replaced my 3" endcaps and the gaskets. The end caps were cracked as they were overtightened. They were curved and easily broken due to overtightening. The new ones were flat. The mounting bolts or the threads on the heat exchanger were not damaged. The new caps were bronze at $ 30.00 each. I highly recommend replacing them. But if you think the threads on the heat exchanger is stripped, it is time for a new heat exchanger.
Visit here

Heat Exchanger | Sail La Vie

mei1970.org

 

[Richard19068]

I have the old style small HX on my M18. It only has one endcap but I have had it off a few times over the last 23 years with no problem. I do usually remove the HX from the engine before taking off the endcap because I'm usually cleaning it up and rodding it out anyway. It's a good idea to replace the endcap gasket if you are removing the cap(s).

 

[odaydokay]

Thanks for the input fellas. Much obliged.