No heat for me!

wynkoop

Member II
So I have been spending as much time as I can on the boat during the current crisis. Today I did some more run tests on the 1GM10 install looking for unusual vibrations, things moving that should not, and things not moving that should. Checking for chafing of wires or hoses and making adjustments as needed.

After running the engine for some time it got up to almost 140 degrees as measured at the installed temp sensor, but the coolant entering the heat exchanger, as measured at the fitting at the top of the engine shows 86.9 degrees.

When I had the Palmer p60 installed I had a car heater in the cooling loop and it would really warm the boat up when the engine got up to temp.
It seems on my fresh water converted 1gm10 with 44 degree seawater I will never be able to warm up the cabin.

In the photo attached the old analog gauge is connected to the 1gm10 temp probe and the digital probe is attached to the metal fitting where the water exits the engine after cooling.

It is starting to look a lot like I can no longer get enough waste heat to heat the cabin while underway.

It would seem there is enough coolant bypassing the engine that when mixed with the hot coolant out of the engine the temp at the junction of the bypass and engine out is just going to be too low.

Ideas?
 

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Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Not the same engine, but for over a decade we have enjoyed a Heatercraft cabin heater that is series-plumbed into the coolant loop that also goes to our hot water tank coil. Acts just like a "car heater" and once the engine warms up for about 20 minutes it can transfer a lot of heat into the cabin.
The closed cooling system on our three cylinder diesel runs about 165 deg.
IMHO there is a lot of 'waste heat' in these small diesels, altho the smaller the engine the less would be available. Our engine is just under a liter in displacement.
You may want to try putting split-foam pipe insulation over the hoses that go to the heater. I did that for ours. And, at idle, ours puts out less warmth, than it does under load at 2500 rpm. Quite a difference, actually.
 

wynkoop

Member II
I have no idea what Thermostat I have. I have not even located it yet. Heading to the boat in a few minutes, but probably not going to pull the stat out. I muck something up would be hard to replace these days.
 

wynkoop

Member II
Loren that temp reading is at the OUT from the engine. That is as hot as it is going to get. It indicates the amount of bypass water is high enough that the mixed coolant temp is that low.

Might be that my little electric pump is too vigerous.
 

Tin Kicker

Member III
Sounds like the t'stat is stuck open.

Simple test is to put it in a pan of water on the stove with a thermometer and see when it opens. Or just replace it pre-emptively.
 
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supersailor

Sustaining Member
The cooling water is closed off by the thermostat until the engine reaches operating temperature. That will be between 160 and 180 degrees depending on the installed 'stat. The engine is not likely to warm up enough to open the 'stat except under load. You will get no cabin heat until the 'stat opens. Pulling the 'stat would be a big mistake because an engine that runs under temp is one that builds up large amounts of carbon.

Look in the specifications page of your installation manual and it will tell you what thermostat is installed.
 

Christian Williams

E381 - Los Angeles
Moderator
Blogs Author
Check the recommended thermostat for a fresh water cooled engine. They're easy to remove and confirm what you have. Sea water cooled version is 140. FResh is 160-180.
 

wynkoop

Member II
Well this was raw water cooled before, but I fixe that. Engine never had sea water in it.

I suppose it is time to order a stat and a gasket. God knows if/when it will arrive. I do not suppose it is of a size I can get at an auto parts store? I really do not want to pull the old one without a new one and gasket on hand, but I bet if I got the temp to 160-180 I suspect the coolant would go up to 120 or so which would provide heat.

Thanks!
 

debonAir

Member III
tstats are pretty common and generally engine makers use off-the-shelf commodity pieces (and then marinizers quadruple the price after changing the part number for you). You can ebay a 1gm10 tstat for $40. There are youtube videos of water pump replacements and I'd bet the tstat housing is close by the water pump outlet.

You'll want a hotter stat for fresh water cooling like Christian says, or suffer carbon and lower fuel economy. The lower temp stat for seawater cooling is used to avoid salt buildup in the engine and is a compromise against engine health/economy.
 

supersailor

Sustaining Member
I change my thermostat every three years. The lack of daily usage means it is inactive and shut most of the time. It can easily stick over time. I don't want an overheat While running a rapids or a rough area. It did happen to a friend up here. He burned up the engine trying to get out of the grip of the current. For those of us who have Universals, the Kobata dealer can supply the thermostat for 1/4 the price of the Universal dealer. It's the same unit. You also can get parts for Betamarine through Kubota for 1/4 the price. Plus the Beta engine is extremely reliable.
 

wynkoop

Member II
My big issue is with the current worldwide situation I do not want the boat to be unable to get underway if I scronge the gasket while changing the tstat, so I am going to wait on that job for now, but will get a stat & gasket as soon as I figure out which one I need.
 

supersailor

Sustaining Member
I made my own gasket after not finding one. Made a spare also that I put in my parts kit. I used an exacto knife to cut the stock material (available at any auto parts store). Try making a run in the boat and getting the engine up to temperature. You may find you don't have a problem. To me, the engine sounds like it is operating the way it should. Once up to temperature, the 'stat should open and you will get heat.
 

supersailor

Sustaining Member
I made my own gasket after not finding one. Made a spare also that I put in my parts kit. I used an exacto knife to cut the stock material (available at any auto parts store). Try making a run in the boat and getting the engine up to temperature. You may find you don't have a problem. The raw water (salt in most of our cases) runs all of the time and can be checked by simply looking at the exhaust and making sure there is water spitting out with the exhaust. If your heat comes from the fresh water cooling, you won't get heat until the thermostat opens at 160 to 180 degrees. This is exactly the way your car works.
 

wynkoop

Member II
Bob,

I am in no hurry to take out the stat, and it coming out for possible replacement will not happen until the boat has run around NY harbor under power for a while, but I am thinking I will still have far less heat than the raw water cooled Palmer setup provided. With it 140 degree water was coursing through my heater as soon as the engine got up to temp, and of course the water at what ever temp was constantly feeding into the heater.

Based on the differences I am seeing between engine temp and coolant to at the exit junction (where the bypass and engine exit meet) I suspect the max I will see there will be in the order of 110 degrees if I do change the stat to a higher temp one down the line.

110 degrees is probably marginal for heating the cabin, but I will take what I can get. I normally keep the boat in the water all year long and enjoy using it in the dead of winter, thus the engine waste heat for cabin heat.

I am also, now that I have converted to diesel, considering one of those diesel fired heaters. Would love to have one that was hydronic so as to be able to preheat the engine, but that is probably a next fall project. Too many other things to do before then.
 
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