The Stovebolt Site Forums The Shop Area Engine Shop 216 engine variations and overheating

I recently purchased a 1946 truck with a 216 engine. It starts right up but overheats within 5 minutes of driving and could use some help from the experts. The engine looks to be rebuilt and it has a new aluminum radiator. Here is what I have done.
1. Ran with and without thermostat - Still overheats (tested thermostat and opens at 160 degrees)
2. flushed radiator and engine and has good flow no rust- still overheats
3. dialed in the timing - still overheats (Note: It has a new distributor with no vacuum unit)
4. water pump looks to be working fine and both radiator hoses run hot
5. Did an engine block and head test with blue die and no sign of carbon leak in coolant
6. no sign of coolant in oil

I have a extra complete 216 engine from a 1937 truck that I was planning to use for extra parts and I realized that the water pumps are different. I am now wondering if during the rebuild that maybe the guy that did the rebuild might have used something from an older 216 engine that is causing the coolant to not flow properly. When I used a heat gun on the engine the block looked to be cool but the head seemed to run hot. Here are my questions.
1. Could the engine/head have a coolant block in it? Maybe a part from a earlier 216 was used that does not line up the coolant flow?
2. Will a 216 head from a 1937 fit on a 216 from 1946?
3. Any suggestions on where to go from here?

You're on the right track. You could have a blown head gasket or blocked coolant passages. I would remove the head and inspect it carefully. Verify that the coolant passages line up with the corresponding passage on the block. If they do, inspect the gasket carefully and look for breaks. If you don't find any breaks in the gasket, lay it on the block and see if any of the passages are being blocked by the gasket. You could be looking at a very inexpensive fix.

1941 and later 216 heads are scalloped down the drivers side around the head bolts, earlier are straight.
I have seen the earlier head used on a later engine without a heating problem.
When I hear of a heating problem and everything has been checked out, I think about ignition timing. Retarded ignition ignition timing can cause overheating.
I have also seen where the lower radiator hose collapses when warmed up.
Lower radiator hoses should have some sort of wire coil in them to prevent collapse.

Thank you guys for the input. I am still a bit of a novices when it comes to working on engines but hopefully I can figure this one out. My lower radiator hose is a 2 part with metal tube between so I don't think that can collapse. The ignition timing comment is interesting. I adjusted the timing with a timing light. It looks to be good but I don't know what more I could do other than that in regard to ignition timing. I do have an older 1937 distributor off of my 216 parts engine with a vacuum line and adjustable dials that I could put on it. Do you think that might help? It currently has a new aftermarket distributor.

I have not pulled the head off yet but I think checking the coolant passages in the engine and head gasket would be good.

Scott, as you have noticed the early water pumps for the 216 (37-40) are different than the later 216 (41-53). Earlier pumps have one hole and the later two holes that connect with the water passage of the block. Since your engine overheats immediately I am wondering if a mismatch of pump to block may result in no flow at all. Before pulling the head why don't you pull the water pump just to be sure.

I found out about this when I ordered a new pump for my 37 and ended up having the original rebuilt. I confess I am not certain it matters but fairly easy to check before pulling the head.
Kent

While a wrong pump or gasket could be the reason, a distributor without a vacuum can is a tall tale sign.
Personally I would try the dizzy with the can and hook it up on manifold vacuum for starters.
Not enough advance is IMHO the number 1 reason for getting hot while idling or in a traffic jam.

Can you see water flow in the radiator when the cap is off and the stat opens? You should see a current in there.

I put a head gasket on wrong when I was in college on a 351W. It blocked rear passages of the head. Never showed hot, but over 18 months it cooked the rear cylinder. Unless all passages are blocked I can't see it showing hot on the gauge unless gage is reading off rear of the motor.

The gauge does read from the rear of the head and the rear passages are the ones the have the tendency to get plugged. Does the rear engine block drain petcock (located on the drivers side) flow fully?

4. water pump looks to be working fine and both radiator hoses run hot

The lower radiator hose should be noticeably cooler than the upper radiator hose when the engine is running at operating temperature.

The upper one will nearly burn your hand. You should be able to grab the lower one without burning your hand.

Is the crankshaft turning the water pump without slipping? Could the crank pulley be slipping on the harmonic balancer where the two are bonded with rubber? Do the belts match the pulleys, e.g. 1/2 inch belt in 5/8 inch pulley bottoming in the groove? Could you have somehow gotten a reverse-pitch agricultural-equipment fan? Could the gauge be in error?

All of these ideas are very helpful. I am still new to a lot of this. I am out of town for a little while but when I get back I will try these things and give you all an update. Thank you for all for your feedback.

I know you pulled the thermostat to see if there was any improvement, but the t-stat offers flow rate control, they often run hotter without a proper functioning t-stat installed.
have you reamed out the block from the driver side rear block drain using a coat hanger etc?

Overheating with a head gasket issue generally causes pressure build up in radiator. Get a cooling system tester that pressures up the system and see if it holds pressure, leave it on for several hours, and then take the plugs out and see if there is any coolant in that cylinder. If the radiator is clogged, after it overheats, put the palm of your hand on the radiator face, it should be hot if it is overheating with NO cool spots anywhere.



d

Kudabull All that advice applies,somewhere saw one that water pump impellar slipped on the shaft,look at that too . good luck

I took the engine block petcock out and no flow. So the engine was definitely not rebuilt. I put a coat hanger in the hole and I couldn’t get very far. Lots of hard crud it looks like. How deep is that hole? I don’t want to damage anything by forcing something in the hole. Any reconditions on how to remove the crud without pulling the block?

It is difficult to adequately clean out the water jacket with the engine in the truck.
That petcock is at the bottom of the water jacket. Just cleaning the area right behind it will not be enough to solve an overheating problem.
You need to be able to clean out the bottom of the entire block. Most times there is nothing available to dissolve Stop Leak.
I had a real bad one with over a pound of black junk in it. The only way to clean it out was by completely tearing down the engine. Freeze plugs, water pump, head, petcock all needed to be removed in order to break this mess up into small enough to get out.
I used a steel rod down the block holes (which supply the head with coolant) to break up the junk not accessible from the freeze plug holes.
It was a chore to clean that block.
That black junk was likely several doses of stop leak added over a number of years to extend the life of the very expensive (back in the day) radiator.

When I had my engine out, I was still able to drain coolant out of the drain at the rear of the block, but on removing the core plugs found a bunch of crud halfway up the rear core plug (behind the bell housing). This was after filling the block with radiator flush and letting it set for a few days. I used a pressure washer and other implements (coat hanger) to clean it out, but I didn't remove the head as likely most of the crud was in the lower rear portion of the block where there's less flow. I expect mine to be fine, but the OP's may need a more severe treatment.
Don't be afraid to poke around in the block with a coat hanger or other implement. The only thing you might damage is the oil line that runs between cylinders 3 and 4 up to the rocker arm shaft. And you won't be able to reach that from the drain hole. If the cast iron is thin enough that you could damage it with a coat hanger, that engine's a boat anchor at that point.

Update on the overheating issue:
Thanks so much for the input so far. Belt looked tight water pump working good and functioning correctly. I was able to free the crud out of the back drain hole with a small punch and hammer. When the dam broke chucks came out. I then flushed the block with a hose and more chunks and "mud' came out. Took it for a ride and it overheated again but it took a lot longer to get hot. block was reading 170 degrees and the head was reading 235 degrees from my heat gun. At this point I decided to remove the head, freeze plugs and water pump and cleaned all the water passage ways I could with a coat hanger, compressed air and a flashlight. I got out about a dozen or so chucks of pieces that looked like corn flakes and more mud type materials out of the block. But overall I dont think it looked that bad. Head gasket looked ok. From what I could tell all the passageways are now clear.
So I guess I need to put it back together again. I am hesitant on pulling the block because I am nervous that I will be able to put it all back correctly. My skills are about a novice level. When I took the head off I took lots of photos and labeled everything.
Any other recommendations before I put everything back? I am not sure it it matters but the system was converted to 12V recently before I purchased the truck (new started & alternator) I am just mentioning this because it is yet another change that was done to the truck. Also I was thinking about putting the original radiator back in instead of the aluminum upgraded one that was on the engine then I got the truck. I prefer to get the truck back to stock as much as possible. Any input would be helpful.

While you have the head off, it would be a good idea to have a machine shop pressure test it for leaks, and/or do a "magnaflux" inspection, looking for cracks. This would also be a good time to have the machine shop do any valve-related work, such as regrinding or replacing valves, and inspecting the valve guides for wear. Even if you end up rebuilding the lower end of the engine at a later date, the head work will be done already. Good luck!
Jerry

Good call Jerry. I took the head to the machine shop yesterday and will get it back in a week or two hopefully.

Kudabull This may be way off but I recall seeing a coolant distribution "tube"that went in the old blocks right behind the water pump discharge. See if some of the old timers ?? chime in on it. Anyone see that ???

Kudabull While your head is off get a screwdriver that will reach the bottom of the water jacket and with a hammer knock out the build up in there. As someone said watch out for that oil line,outside of that not much to hurt. Can measure the depth front to rear more build up in the downhill rear of the block.

When I restored my '37 with a 216 I had to replace the head because it was cracked across an exhaust valve causing lack of compression in one cylinder. I then went about cleaning out the water jacket with the block on an engine stand. I flushed with water, blew it out with compressed air, fashioned a vacuum attachment with heater hose to stick into freeze plug and water pump holes, dug around using the smaller holes with a long screw driver, ect. There was 3-4 inches of compacted dirt/rust front to back. Finally, I started to feel I had it cleaned pretty good. Today, it does not overheat at all. I looked to see if you were in CA (and you are) because in warm climates they didn't need antifreeze and just ran water for coolant, leading to rust and particulate buildup over the years in the water jacket.
If you are persistent, with the head off, I believe you can clean it adequately without removing the block but it will be awkward to say the least. Follow the great advice to service the head now. You will get this.
Kent

I had a similar overheating problem with the original 216 in my truck back when I restored it in high school. Progressively got worse until I couldn't drive it around the block. Never could figure out why. 19 years later after university and starting a new career and finally having time for the truck again, I pulled the engine to paint it, and found a leaky frost plug. When I pulled it the water jacket was full of crud up to the bottom of the frost plug. I'm not re-installing that engine anymore, but after reading this post, it reaffirms what I thought was the cause.

I ended up having the block hot tanked to clean it out before deciding to go with another engine, so didn't get a good look at the crud, but my grandfather had put more than one jar of bar leaks in there. Interestingly enough, that wasn't his go to for radiator leaks. He swore by a handful of pepper to stop a radiator leak.

Finally got my engine back together. I cleaned out the block the best I could, had the head resurfaced and cleaned. The other thing I did was advance the timing. Maybe 4-8 degrees. That seemed to do the trick. The engine runs good and stays around 165 degrees and does not overheat. It seems to run better when the choke is out. When the choke is in it lags a little bit and seems like it wants to die if I don't back off the accelerator. I am wondering if maybe I have advanced the timing too much. Anyone have any experience with this. Thank you again for everyone's comments. Your knowledge is gold.

Does the RPM change as you adjust the idle/mixture screw at idle speed? If not, you may have a vacuum leak. Engaging the choke will generally improve performance when you have a vacuum leak. That vacuum leak represents too much air and not enough fuel.

I just got my 33 207 running and it wanted to trip all over its self when I’m Gave it throttle. I loosened up the collar under the distributor and loosened the spark advance cable and crept the distributor in the advance direction, now it’s strong when the throttle is used to rev it up, hope this helps.