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Missouri Mule

Block heater question

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Tonight I got a block heater mounted on my 756 and it seems to work great except once in a while I hear the check valve rattle. I was trying to mount it along the frame rail and keep it discrete.  So after I installed it I read the directions "typical guy" and noticed it says to mount vertical. Any reason in particular for this? I assume it's to keep air pockets out of the heater? Anyway I have it mounted drawing water from the coolant intake plug where the temp gauge threads in and heated water goes in on the other side of the block in the rear behind fuel filters. It originally had one plumbed in here before me. It seems to work great like I mentioned but I wonder why the check valve rattles once in a while. Also I have it mounted horizontally which I didn't realize I shouldn't. I may need to rethink what I have if there's a major reason to have it mounted vertically. Any input here?  I should add I had it plugged in for a while and it had the hose Going into the block nice and warm like it should. The inlet was cold. My theory is to heat the block lower and let it radiate up in fear the other way would open the thermostat quickly and not do much good. 

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Inside the tank is a check ball made of nylon and should be in stalled in a vertical possition for it to work best.

 

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Heat rises, the outlet must be higher than the inlet. Also the upper hose should be as high on the engine as possible to get the circulation going.

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Hot water rises, that's the principle thermosyphon cooling systems used on tractors in the early days till the 1940's.  Pulling cold coolant from around the thermostat is good, plumbing the heated coolant back into the block as far away from the thermostat as possible is really really good, maybe even great!  

You didn't say how big a block heater you put on. A 500 watt is about the smallest I'd put on, a 1500W about the biggest.  A 750 to 1000w works the best IMHO.  I've had 1500W heaters get too hot and shut off, but my 1000 to 1200w heaters warmed my small block Chevy or 7.3L PSD up to 140 degree water temp at zero degrees if I plugged it in all night. Instant heat and defrosters.  You might want to set the heater up vertical for better flow but if the outlet hose is hot and inlet hose is cold you have enough flow to accomplish what you want.

I've made this comment here before,  Do NOT plumb your block heater return hose into the water temp gauge hole with a pipe tee, unless you don't want your temp gauge to work.  The sensing bulb has to be in hot coolant flow, which there is NO FLOW in a dead end pipe tee. You might as well thread the return hose from the heater into the block or head and leave the sensor hanging. In the spring you can remove the heater and reinstall the gauge sensor.

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2 hours ago, DOCTOR EVIL said:

Hot water rises, that's the principle thermosyphon cooling systems used on tractors in the early days till the 1940's.  Pulling cold coolant from around the thermostat is good, plumbing the heated coolant back into the block as far away from the thermostat as possible is really really good, maybe even great!  

You didn't say how big a block heater you put on. A 500 watt is about the smallest I'd put on, a 1500W about the biggest.  A 750 to 1000w works the best IMHO.  I've had 1500W heaters get too hot and shut off, but my 1000 to 1200w heaters warmed my small block Chevy or 7.3L PSD up to 140 degree water temp at zero degrees if I plugged it in all night. Instant heat and defrosters.  You might want to set the heater up vertical for better flow but if the outlet hose is hot and inlet hose is cold you have enough flow to accomplish what you want.

I've made this comment here before,  Do NOT plumb your block heater return hose into the water temp gauge hole with a pipe tee, unless you don't want your temp gauge to work.  The sensing bulb has to be in hot coolant flow, which there is NO FLOW in a dead end pipe tee. You might as well thread the return hose from the heater into the block or head and leave the sensor hanging. In the spring you can remove the heater and reinstall the gauge sensor.

Dr Evil, thanks it is a 850watt. On the German motor there is a spot on the coolant manifold that had a reducer and elbow already in it from the last block heater. The coolant sensing bulb sets behind it in the manifold. I'll try to get a picture. I'm sure this is how 90% of them probably are. Someone else might know what this threaded place was intended for. 

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3 hours ago, augercreek said:

Inside the tank is a check ball made of nylon and should be in stalled in a vertical possition for it to work best.

 

I suppose they want gravity to do the job of a spring. In my case I don't even need a check valve, so when water rushes by it rattles a little I guess. 

I have it plugged in now. We will see how good it circulates the way it is. For the Midwest if it works decent it will do what I need. It just doesnt get that cold that long here. I don't see a way to mount it vertical that won't be unsightly. Since i dont use one that often if this doesn't work maybe I'll look into a different style such as lower rad hose. 

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Dad's 826 had a lower radiator hose in it for years until it started leaking. I always thought those were a cleaner look and it worked well too. 

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Nice thing about a tank heater is that if it ever goes bad you can pinch off hoses and r&r heater without having to drain coolant, usually goes bad on the coldest day of the year.

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Well today was the test. I have it coming out of coolant manifold down along the frame rail on right side with 850 watt tank heater horizontally hidden behind frame. Then outlet under tractor between oil pan/bell housing and then up slightly to threaded hole in left rear of engine. It was plugged in for 2 hrs in 10* weather and fired right up. The block heater was percolating nicely. By all means I'm sure it should be mounted vertically. I used 90 elbows at the ports and ran 5/8" heater hose (red) and a red heater. It is tucked away nice and neat. I looked it over for a while and just didn't see a way to change it that I would like. I guess if I lived further north where it got colder I wouldn't care as long as it did the job. That's why I normally like freeze plug heaters because they look clean. If I burn the heater up because of installation negligence oh well. I just thought I would let everyone know it worked nicely. Thanks for all your thoughts and ideas. 

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