Missing heat exchanger end cap bow side

[copierkat]

Hi all. Wanted to make sure no water in heat exchanger on my 83 Celebrity boat with 470 Mercruiser cause I am in Minnesota, and it's starting to get cold out! Went to examine heat exchanger and noticed bolt in bow end of exchanger, but no cap. I just bought this boat last winter, had it on muffs once this spring, (noticed bunch of water inside hull after starting, now I know why). Can I buy just the end cap for bow side of heat exchanger? Where would I look for a part such as this? Why would previous owner leave that off? Took bolt out of stern side of exchanger, but could not get end cap off. Also, drain plug for seawater drain would not budge. Loosened plug on exchanger for antifreeze with no problem. Did not want to snap other one off so left it. Might spray with PB Blaster. Do I need to worry about water freezing inside exchanger? Anything else I should be draining? Thanks for any suggestions. Dave

 

[wrestling coach]

Re: Missing heat exchanger end cap bow side

I would look around the boat a bit for the end cap. Check the bilge perhaps. This may have been the previous owner's way of draining the heat exchanger for the winter and he placed the cap somewhere on the engine or in the boat. Winterizing these motors is pretty simple. Get the fresh water drained out of your HE and you are done. The block side of the cooling system has anti freeze in it. Check it to be sure you are protected well down to below 0*F in your area. End caps and gaskets are available in 3" and 4" depending on which size you have. Probably 3" on an '83. End Caps | Gaskets | Mercruiser | Basic Power

Dennis

 

[stonyloam]

Re: Missing heat exchanger end cap bow side

Probably the po took the end cap off because he could not get the raw water drain plug out. If you can lower the bow of the boat enough so that the front of the exchanger is lower than the back it will drain all of the water. That is all you need to drain. If you ran it for a while with the cap off, there was no water going to the exhaust elbow, so you may have damaged your shutters or engine exhaust bellows, might want to take a look over the winter.

 

[copierkat]

Re: Missing heat exchanger end cap bow side

I would look around the boat a bit for the end cap. Check the bilge perhaps. This may have been the previous owner's way of draining the heat exchanger for the winter and he placed the cap somewhere on the engine or in the boat. Winterizing these motors is pretty simple. Get the fresh water drained out of your HE and you are done. The block side of the cooling system has anti freeze in it. Check it to be sure you are protected well down to below 0*F in your area. End caps and gaskets are available in 3" and 4" depending on which size you have. Probably 3" on an '83. End Caps | Gaskets | Mercruiser | Basic Power

Dennis

Thank you Dennis. I will search the boat good and use your link to purchase a new one if it cannot be found. For some reason, the antifreeze is low, cannot see any in the tank, but some did come out when I loosened the drain plug on HE. I will add 50/50 mixture to top it off. Your help is appreciated!

Probably the po took the end cap off because he could not get the raw water drain plug out. If you can lower the bow of the boat enough so that the front of the exchanger is lower than the back it will drain all of the water. That is all you need to drain. If you ran it for a while with the cap off, there was no water going to the exhaust elbow, so you may have damaged your shutters or engine exhaust bellows, might want to take a look over the winter.

Thank you Terry. I did lower the bow as far as I could thinking the same as you. When I ran it in the spring, it was for 5 seconds max. Don't know if this was long enough to damage shutters or exhaust bellows. I will take a look. Will the damage be obvious? Appreciate your help! Dave

 

[Scott Danforth]

Re: Missing heat exchanger end cap bow side

your heat exchanger was made by Champ Products in Sarastota florida. it is now Alfa Laval. either way, contact them, and you can get a new cap. you may need to take a pic.

I would also get both gaskets as well.

 

[copierkat]

Re: Missing heat exchanger end cap bow side

your heat exchanger was made by Champ Products in Sarastota florida. it is now Alfa Laval. either way, contact them, and you can get a new cap. you may need to take a pic.

I would also get both gaskets as well.

Thanks Scott. I did not realize they were model specific and did not come with gaskets. I will measure it and take pics. Helpful info! Dave