The Stovebolt Site Forums The Shop Area Engine Shop Overheating problem 1937 216 used Engine...

Working with a 1937 216 engine that I just installed as a replacement in my truck... Unfortunately, I got with no history with the engine (other than I was told it is good) Got it fired up, BUT I have an overheating problem... Water boils out from the overflow pipe around 190F- 200F.

I have checked the following...

1- Air trapped in the system in the rear (temp gauge boss)
2- Water pump belt tension
3- Radiator cap (R-3)
4- Coolant level

On the other hand, engine starts right up and there is no white smoke...

1- Checked all spark plugs and are clean/normal. Have not done a compression test yet...

Radiator was cleaned out and pressure tested...

Could the water pump impeller spin freely inside the housing? What am I missing? What should be the next thing to double check? Thank you.

NAPA sells a "block test" device that checks for combustion gases in the cooling system. It consists of a rubber squeeze bulb that draws up gases from the radiator through a blue liquid that you pour into a reservoir. If a little exhaust gas is present, the liquid turns yellow. A bad leak turns it green. I use one of these testers frequently, but if you don't want to buy ir fot a one-time use, most good auto shops will have one and they can do the trest dor a small service charge. O'Reilly's sells an identical-looking kit, but for some reason, the NAPA test fluid works better.

You could also isolate the engine from the rest of the cooling system by using two long flexible radiator hoses coupled together and applying air pressure to the cooling system after filling the engine with water. If you put much pressure to the radiator and/or heater core, you'll create leaks. If the air pressure drops, remove the spark plugs and spin the engine with the starter. Coolant will squirt out of whichever cylinder has the leaky head gasket or a crached head.
Jerry

You should be able to take the cap off and see the flow at fast idle. If you have a thermostat installed, I would try removing it to see if that helps. The thermostat does cause a restriction.

Hello Jerry,

I could try the block test liquid I suppose, but before doing that I remembered the bubble test, but also decided to check the new thermostat...

1- The bubble test did not reveal anything at all, so I must have some other type of blockage somewhere in the block or cylinder head?

2- New Stant 160 F thermostat did not open at 160F, but closer to 170F and was very slow. It also would not open evenly until about 180F... An old Delco 180F thermostat opened about 170F and was very quick and opened evenly...

I decided to use the Delco thermostat, this time the same thing occurred, only it took a little longer for the coolant to shoot out of the overflow pipe...

So the question after doing this is, could the cylinder head still be a major problem? or is it an obstruction in the block/head, or the fact that '37 216's do not like thermostats... It did not come with one, so I wonder...

Frequently dirt collects in the lower water jacket, best to open all drain plugs and clean out with a piece of wire that you can wiggle around to clean it out. Probably not the main reason, but contributes. Also contributes to frozen blocks if not open, however, probably not in FL.

Ed

"Bubble test"- - - -how about a few more details on that one? I've seen people disable the water pump and run the engine for a minute or so with the block filled up to the level of the thermostat housing, looking for bubbles from a head gasket or a cracked head, but it's usually inconclusive. I've had a lot more success by locking the crankshaft and applying air pressure to each cylinder rather than running the engine. The block test fluid is still my first choice before doing any disassembly. You're going to receive all sorts of suggestions- - - - -pick whichever one that floats your boat, but most of them are going to be worth what it costs you to read them. Have fun!
Jerry

One thing I haven't seen mentioned is not to fill the radiator to the top. Allow about 1 1/2 inches below the top of the radiator for the coolant to expand. If you fill it to the top, when it gets warm it will burp a bit out.

Hello Ed, by opening all drain plugs do you mean remove all freeze plugs and clean the block? By bubble test I mean remove all spark plugs except for the cylinder you want to check, crank the engine and see if any bubbles form on the cylinder that has compression... Do the remaining 5 the same way.

The last thing I did was to remove the thermostat and not over fill the radiator... I was overfilling the radiator before. Same problem. I even tried to run the engine at a higher rpm to maybe clear it out but nope, same issue... I must have a blockage somewhere!

Philippe, not the freeze plugs, just the two drain plugs, usually only one has a petcock fitting in it, but there is another one at the other end of the block, usually with just a plug in it.

Ed

Hello Ed,

There is only one petcock on the driver's side of the block and another one on the passenger side but on the radiator...

After reviewing the workshop manual I found a section dealing with reverse flushing the cylinder block and decided to give it a go... In my mind there were three things to do before having to do the extreme, which was to pull the cylinder head to clean the water passages:

1- Reverse flush the block, and use a wire to loosen any rust scales and crud from the rear left side of the block.
2- Use compressed air through the same opening to help move the stuff around...
3- Remove the water pump if necessary to clean scales from the block accumulated in that area...

I spent quite a bit of time with that setup that allowed me to do that until I got nothing but crystal clean water from the rear petcock, as well as what was being drained from the lower section of the block up front... I alternated that and blowing compressed air though the rear opening to loosen stuff up. After 3 hrs. of that, I decided to put it all back together and run the engine... To my surprise the engine run about 170F without the thermostat and never reached 180F. Success at last!!

In the next few days I will use my old Delco 180F. thermostat and a 50/50 mix of antifreeze (despite being in Fl.) and finish the job as it should be...

For all you guys who do not believe in antifreeze in warmer climates, do yourselves a favor and save your blocks, heads but mostly water pumps from corroding and forming rust barnicles by using antifreeze... I removed the water pump from the original engine and despite not leaking or having any play, the impeller was ful of calcium and rust deposits from water usage instead of antifreeze...

As all you guys out there know with early 216 engines, single hole water pumps are expensive and imposible to find, so save what you have and use antifreeze instead of water on your engines!...:)

You gotta love a success story. Way to go!

I was actually very surprised that it cleared itself out, since it was so bad before... It would get up to temperature fairly quickly. I already had resigned myself to having to remove the head to clear the water passages. Thank God it worked out... One less thing to do and on to the next challenge...:)

Phillipj Look out for a mouse nest in the block,have seen them move in almost overnight !!