Coolant Block Drain Location

[KZW]

I'm trying to find the block drain location for the coolant on my M-25 XPB. The PO used Prestone, but Practical Sailor recommends a diesel coolant used in commercial rigs. I'm not sure the chemistry will mix so I want to drain all of it.

Would one of you C-310 owners let me know if the pictures show the drain? The first picture is the front/port side of the engine. The second is a zoomed in shot of what I think is the drain, located on the port side about an inch below and three inches back of the forward port engine mount. The third is a picture from the manual

If that is the drain, how do you drain it without getting it down into the bilge? There is very little room to work on the port side of the engine and there is no hope of getting a pan under the drain. mUniversal Marine Engine Manual, pub 200550, Feb 10, page 14, shows the coolant drain above and aft of the oil filter, located on the port side of the engine. The drawing in the manual doesn't quite match what is seen in the pictures I've posted.

I really don't want to put a wrench on it and open up the wrong thing.

 

[Tom J]

I believe what your arrow is pointing to is a cap at the junction of the oil pressure sending unit. I removed it at one point and hooked up an oil pressure gauge temporarily.

 

[KZW]

Thanks. It is really hard to get down there on the port side and look around. I will try it again tomorrow. Maybe I will see something that matches the diagram!

Your response is very much appreciated!!!

Cheers, Craig

 

[Tom J]

Thanks. It is really hard to get down there on the port side and look around. I will try it again tomorrow. Maybe I will see something that matches the diagram!

Your response is very much appreciated!!!

Cheers, Craig

I'm jealous. You get to work on your boat in the winter!

 

[JK_Boston_Catalina310]

The way I found the drain was to remove the stairs so I could lie down next to the engine. Then I found the teardrop snapped piece of metal. The drain is in the bottom, see the page from the manual you posted.

Curious about the coolant you are going to use. Most diesel guys I know use very cheap stuff. Not because it's better but cheaper and they can get it by the drum. What is wrong with the standard Prestone stuff?

 

[JK_Boston_Catalina310]

I'm jealous. You get to work on your boat in the winter!

Haha. Isn't that because you are Hawaii or something while your boat is back here in the cold northeast?

 

[KZW]

I'm jealous. You get to work on your boat in the winter!

Northwest Florida, some say lower Alabama, really is a great place to live. The cost of living is low, the tide only moves +/- a foot, the bay is large, and the pass to the Gulf is only 12 nm away. Winds are moderate, usually below 15 knots. The water temperature hits 80 degrees by 1 June and dips below 80 on 1 November. I don't put a toe in it outside of those dates. The heat and humidity in July and August can be oppressive, but on the bay the air moves and it is very nice.

The boat is in the water, and sailed, year-round. I do put in a heater and dehumidifier to keep condensation down.

The only problem with living here in paradise is that you must understand that eventually, your house and everything in it, and your boat, are going to go away. It may be next summer, the summer after, or 50 years hence, but it will happen. My rule is that if the wind is forecast to be over 100 mph at my home, I anchor out the boat, put up the shutters, pack important documents, and leave. I've evacuated three times in 25 years. The insurance company will handle the result.

 

[KZW]

The way I found the drain was to remove the stairs so I could lie down next to the engine. Then I found the teardrop snapped piece of metal. The drain is in the bottom, see the page from the manual you posted.

Curious about the coolant you are going to use. Most diesel guys I know use very cheap stuff. Not because it's better but cheaper and they can get it by the drum. What is wrong with the standard Prestone stuff?

I'm not casting stones at Prestone. I understand many folks use it and that is what the PO on my boat put in.

Practical Sailor, Oct 14, ran an article on coolants. They recommended that Diesel-engine owners use heavy duty engine coolants. They recommend Detroit Diesel Cool Plus, pre-diluted at $12 per gallon. However, I cannot find a place to buy it. They also like Peak Final Charge NOAT. Again, I could not find any locally. They said that either of these should last well over 5 years in the engine. Finally, they indicated Zerex G-05 is a reasonable heavy duty coolant, but not as good as the first two. I can buy Zerex and thought I'd give it a try. Undiluted, a gallon was $17 plus tax.

I am no expert, I'm repeating what PS said.

 

[Tom J]

Haha. Isn't that because you are Hawaii or something while your boat is back here in the cold northeast?

Exactly, Jesse. Being on Maui is great, of course, but I sure do miss Andante. We do have kayaks here, and it is fun to go out and play with the whales. Gets us through the winter.

 

[Tom J]

Northwest Florida, some say lower Alabama, really is a great place to live. The cost of living is low, the tide only moves +/- a foot, the bay is large, and the pass to the Gulf is only 12 nm away. Winds are moderate, usually below 15 knots. The water temperature hits 80 degrees by 1 June and dips below 80 on 1 November. I don't put a toe in it outside of those dates. The heat and humidity in July and August can be oppressive, but on the bay the air moves and it is very nice.

The boat is in the water, and sailed, year-round. I do put in a heater and dehumidifier to keep condensation down.

The only problem with living here in paradise is that you must understand that eventually, your house and everything in it, and your boat, are going to go away. It may be next summer, the summer after, or 50 years hence, but it will happen. My rule is that if the wind is forecast to be over 100 mph at my home, I anchor out the boat, put up the shutters, pack important documents, and leave. I've evacuated three times in 25 years. The insurance company will handle the result.

I know what you mean. I used to live in Englewood, FL, and hurricane Charley missed our house by a couple of miles. The sailing out of Stump Pass and Charlotte Harbor was great, though.
We had to evacuate two years in a row because of tsunamis, so, like you said, living in paradise has it's price.

 

[Tom J]

I should have said we had to evacuate the condo in Maui!

 

[KZW]

Tom J,

Found the drain. How do you keep from dropping coolant under the engine and into the bilge????

I can't fit any kind of pan under there.

Cheers, Craig

 

[KZW]

OK,

How does one drain the coolant that goes to the heat exchanger in the hot water tank????

 

[Tom J]

Tom J,

Found the drain. How do you keep from dropping coolant under the engine and into the bilge????

I can't fit any kind of pan under there.

Cheers, Craig

I'm not sure, Craig. I did pull my heat exchanger out last spring and changed the hoses, but I didn't drain the engine. Mainly because I had the same issue you do. What coolant did drain went into the engine bilge and I used paper towels and sponges to mop it up.

 

[JK_Boston_Catalina310]

OK, How does one drain the coolant that goes to the heat exchanger in the hot water tank????

The engine bilge is separate. I let it leak into that bilge and cleaned it with a shop vac. Same for the heat exchanger.

For the water heater I disconnected both sides of the bypass hose at the thermostat housing. Then I used a drill pump to flush with water before changing antifreeze.

Good luck,

Jesse

 

[KZW]

"For the water heater I disconnected both sides of the bypass hose at the thermostat housing. Then I used a drill pump to flush with water before changing antifreeze."


Excellant idea. I will give it a shot. Thanks!

 

[peter_ms]

Very timely; thanks, I was looking for it too
I am pulling the transmission so replacement Heat Exchanger mounting brackets etc is all part of the work.
I use a shop vac for almost everything including winterizing the fresh water system
Peter