The Stovebolt Site Forums The Shop Area Engine Shop 216 Water Pump, T-Stat, and Other Cooling system Questions

Water Pump is being sent out for rebuilding with a 3 week turnaround. Radiator will be ready tomorrow.

The T Stat installed was a 160 degree rated one. I intend to replace it with a new 160 since the truck ran perfectly fine with it and reached the normal operating temp in a reasonable amount of time. Manual says 160 or 180 can be used.

1. Since there is no bypass hose on these trucks, should I modify the T Stat with a drilled hole in the flange? If so, what size?

I think JonG mentioned the FailSafe brand T stat. It has some sort of goofy looking mechanism to lock it open or something if it gets too hot or whatever. That's what was in there. I don't think he liked it much.

2. Should I get the FailSafe or just go with the normal kind?

3. I normally use Green ethylene glycol coolant mixed 50/50 with distilled water. Is there any advantage to buying the premixed stuff? Seems like you're just paying$12/gal for water instead of 99 cents for distilled but maybe it has other qualities I'm not aware of?

Someone else on this forum, I think that guy from Germany, said that distilled water shouldn't be used.

4. Do any of the water pump bolts enter the water jacket?

I'm pretty sure all the pump attaching bolts go into the water jacket. If you want something a little better than plain tap water, buy a couple of gallons of "filtered" water at Walmart to mix with the antifreeze. No need to go for the pricey distilled stuff- - - - -you're not filling a steam iron or something else that deliberately evaporates it and leaves residue behind. The "reverse osmosis" filter machines that dispense drinking water should be plenty clean for radiators, and you can bring your own containers if you choose. A 1/8" hole drilled into the thermostat will be plenty to prevent an air lock from forming. Just fill the radiator slowly and wait a few minutes before topping it off. Leaving a couple of inches for expansion in the top tank won't hurt if you don't choose to use a catch can.
Jerry

Thanks Jerry.

When it comes time to re-install the water pump, should I use RTV or anything?

I'm inclined to just use a light coating of wheel bearing grease on each side of the gasket. I'll have to look more closely at the block but I don't think the pump had any sealer on it before. The axle grease seemed to work just fine on the T-Stat housing with my ad-hoc repair a couple weeks ago. It even withstood the 55psi water pressure during my head gasket test.

Do I need to use sealer on the threads of the 4 bolts?

Permatex Super 300 would b my first choice- - - -a thin layer on both sides of the gasket and a drop or two on the bolt threads.
Jerry

Does the block petcock on the engine drain out all of the coolant? Most? Some?

I'd like to drain all the tap water out of the engine before putting everything back together and filling with fresh coolant. Metro Atlanta tap water is fairly soft and has very little mineral content so water heaters last a long time and cooling systems don't corrode like they do with hard water but I'd still like to get as much out as possible.

Yes, most of the block coolant. Park the truck nose high to drain the most possible.

Hi Gang,

The water pump showed back up in the mailbox today from the Flying Dutchman. I'm excited to put everything back together but I have to do some work on my mom's truck tomorrow,

Her key got stuck in the ignition while she was out at a shopping center. Key wouldn't turn, steering wheel wouldn't turn, etc. Not good in 100 degree Ga heat. Anyway, depending on how that goes, I may be able to re-assemble Ol' Roy on Sunday.

He sent it back to me US Mail on Tuesday. Cost $18. UPS charged me $50 to send it out there and it took over a week.

Would you use the Permatex Super 300 on the inner water pump gasket ( impeller cover) as well as the pump to block surface?

I torqued the pump bolts to 27.5 ft/lbs (25-30 per the shop manual). What about the water outlet/T stat housing? I torqued that to 20 ft lbs but there's no mention of it in the manual. Probably ok.

They're 3/8" coarse bolts so standard torque with your favorite 9/16" wrench should do it. Make sure the thermostat and gasket are seated properly so you don't break of one of the ears from the housing top. Also I hope you didn't opt for the "Safety Stat." I've had several of those fail open when the engine heats a little on a long grade. I no longer use them.

No, I used a normal one. However, it was all for nought.

Buttoned everything up and tested it for ~20 miles. No overheating, no leaking. Temp range stayed within acceptable parameters as tested with infrared thermometer at upper hose, T stat, etc.

Drive to 10 mi to Roswell for gas, no overheating, no problems.

Drive 30 miles home - coolant is boiling out of the overflow tank.

I'm pretty dejected now after all the work - rebuilt pump, cleaned out radiator, new t stat and radiator cap. etc.

No water in oil. No apparent leaks , although I'll fill it up with water this weekend and observe it in the driveway. Engine starts right up with no funkiness and drives like normal.

You didn't mention what the temperature was when "the coolant is boiling out of the overflow tank."
I didn't see anywhere where you mentioned anything about the radiator cap. It may be releasing below 4 # of pressure, thus overloading your overflow tank making it appear to be "boiling out'"

212 +. water outlet was 214 or so. It may have been hotter, I don't remember

It was a rolling boil blowing the cap off the reservoir, not just a normal release into the overflow reservoir. I've been driving this truck for over 8000 miles so I'm used to seeing the reservoir rise and fall under normal use when the engine operates at normal temperature.

It was the same behavior that happened when all of this began a few weeks ago.

I filled it with water a little while ago and half the coolant was gone (2 gal)

New 4# radiator cap

Test the cap. FLAPS loan out a test kit which should include a tester to check to see what pressure the cap releases.
You could just buy a new cap to see if it makes a difference, but at this point, you probably like to know it a bad cap is releasing to soon rather than throw parts at the problem. (I feel your pain brother.)
What level have you kept the coolant in the radiator when the engine is cold?
When a radiator cap releases even when the engine is running normal at 180 degrees, what comes out is violent and is enough to scald all of the dogs in the neighborhood.

Whenall this started i borrowed a 22 piece test kit from Advance. Not a single one of the adapters in the kit would fit the radiator or the cap. Just for fun I checked the 1995 Ford. No go. The kits available don't seem to have adapters for the big "normal" radiator caps found on just about everything from 2000 on back.

It's a new cap. What are the odds that a new cap would cause the exact problem as the old cap? Probably pretty slim.

Both caps have poppets for use with coolant recovery tanks. The coolant recovery system has been working perfectly for three years.

2 gallons of coolant boiled out. It wasn't just a normal release into the recovery tank.

I keep the radiator filled to the top with coolant in the recovery tank at the cold line. For three years the gauge has stayed more or less at 180 and the coolant reservoir rises and falls normally without boiling or overflowing.

Otto how long did you run the engine after buttoning all your fixes without the cap on maybe you just had a airlock I have seen some vehicles be very stubborn with getting all the air out before you put the cap back on

Probably about 10 minutes or so. I did drill a 1/8" hole in the Tstat to prevent air pockets.

If it was an air pocket, it seems pretty coincidental that it resulted in the same manner of overheating as started this whole mess.

It’s been a while for me but usually I would run the engine with the cap off until no bubbles are seen and the coolant should be flowing when you look down the rad cap hole ,I don’t know if drilling a hole in the thermostat would prevent a airlock once the cap was put on . But if you may be correct airlock does not occur to often .

Sometimes those lower radiator hoses collapse on the inside from suction. Back in the day the lower suction hose would come with a wire coil support inside to prevent this.

Brand new hoses. The one I took off had a spring. I saved the spring but did not insert it in the new hose. Probably not the issue, though.

Has your timing moved?

Mike B

I don't know how it could have. The truck starts at the first touch of the starter and runs the same as it always has. I'll check the dizzy to see if it could be loose.

I started the truck up and observed with the radiator cap off for about 30 minutes.

I saw no bubbles appear in the radiator. Just as I observed when this problem began, I can't really tell if water is flowing properly through the system. It wasn't like watching a rushing river through the filler neck.

The engine reached about 190-195 while idling. I decided to take it for a short drive and see what happened. Temp immediately started rising when I got on the freeway until the gauge pegged at 212.

When I pulled into the driveway the coolant was not boiling over but it does have a 4 lb cap so that wouldn't occur until 224.

With a infrared thermometer I shot readings at various locations.

Gauge read 212:
Upper hose at radiator - 210
Bottom hose at radiator - 187
Engine inlet - 180,189
T-Stat housing - 193,206
Cap - 200
Temp Sender - 227, 222, 212,213
JB Weld repair near petcock - 213, 216
Petcock - 208

The engine has a crack in the usual area near the petcock on the driver side that someone made a sloppy looking repair with epoxy of some sort. It never leaked or seeped but after the second overheating issue, I now see coolant seepage. I don't believe this is a cause of the overheating problem. Not enough coolant leaks out there but it is something that will have to be addressed.

I suspect that the higher than usual engine temps may have weakened the repair.

Even if the engine doesn't boil over, 220 is 40 higher than the truck normally used to operate.

What can be causing this? I suspect coolant isn't flowing through the system properly due to some sort of blockage. What happened? Clear water flushed out both ways under high hose pressure. The coolant remains perfectly clean after the over heating.

What should be my next step? Do I run it with a stronger acid solution? TSP? Evaporust?

Oil remains perfectly clean and amber colored with no evidence of contamination of any kind.

Otto, Just a thought but have you checked to make sure the exhaust heat flapper hasn't gotten stuck??? That could divert a continuous load of excess hot exhaust on your intake and from what I have read can add to the operating temps. Your temp increase under load is what brought this to mind.

Remind us again: What Radiator service was performed?

I think you said that both radiator tanks were removed, radiator core was completely rodded out, and radiator reassembled and reinstalled.

Yes the exhaust manifold heat valve works freely and smoothly with no sticking or binding. And yes the radiator was in already pretty decent shape and not plugged up before I had it serviced but it was boiled out with whatever chemical process they normally use

And the radiator core was replaced at some time in the past with a modern design rather than the 1941 Harrison design.

I should also mention that this problem did not seem to gradually develop. There were no trips leading up to the major overheating event where I noticed the temperature climbing unusually or getting too hot too fast or anything like that. I drive the truck regularly all the time and it performed as usual up until the day that it didn't.

As Jethro in Va suggested check to see if the lower rad hose is collapsing. Spent a lot of time and money working on a new engine install in my motorhome. Replaced all hoses with new, not wanting any problems. Engine was fine idling but at highway speed overheated. Checked both rad hoses at idle and both were solid and round. Finally broke down and called my 80 year old father to ask for advice. He gave the same advice as Jethro but recommended I check at high RPM. When the engine RPM was increased to highway speed (in the driveway) the lower rad hose sucked together impeding the coolant flow . Installed the spring from my old hose and overheating disappeared.

No, not collapsing. Old one had spring in it but new one doesn't.

Key words: Impeding Coolant Flow.

If the engine timing is correct and it appears to be, the overheating issue is likely centered on inadequate coolant flow. Which would point to sediment and/or blockage in water jackets, radiator and hoses.

Yes, it has to be a blockage somewhere in the water jacket. Hoses and radiator are fine.

What's the best to way to find the blockage and remove it? No sludge or gunk comes out when flushed with water in both directions.

When pump was off, I blasted water from the front of the engine and through the petcock to the front.

Back when these "enclosed tractors" were new, they were rode hard and put up wet. When a radiator sprung a leak, they added some form of stop leak in order to get those last bales into the barn. This likely happened several times over the trucks life. A brass and copper radiator was an expensive item to replace, and the nearest shop which could repair a leaky one correctly was all the way into town, and the guy charged an arm and a leg (like 2 dollars) to fix it. Stopleak was a nickel.
I had to remove an unbelievable amount of hardened black crud glued to the bottom of the water jacket of a 216. I had to completely disassembled the engine to get it clean. There was nothing which would dissolve this stuff.
I used rods of various sizes through coolant passages in the top of the deck of the block and hammered the crud which was in the bottom of the water jacket to break it up enough to fish it out. I also did that type of chiselling via the drain hole, all of the freeze plug holes and the water pump hole.
It was painstaking and barely doable. No way to do this with an assembled engine.

hard to find a place these days to vat even an engine block!!!!!

Otto, it's been a couple of days since your last post. This happened suddenly, if I followed the posts correctly, right after you installed your pump after a rebuild. Why did you send the pump off for repair? Leaking? Bad Bearing? or was the engine overheating then. That wasn't clear to me.

In case you haven't found the problem, here's some things to check: It's clear that there's inadequate water flow based on your temperature readings. Years ago, I ran a thermocouple down to the lower radiator outlet and another one to the t'stat housing -190 top and 140 bottom. I was looking for a way to increase the temperature delta. Why do you have too little flow? not hoses, not radiator, not t'stat, No bubbles from cracked head or gasket. What's left? Pump not pumping enough water. Why? impeller came off shaft or is slipping? Not likely as it's a press fit, likewise the pulley flange. So for some reason the pump isn't turning or not turning fast enough. Belt slipping? I'm sure you checked that. What about the rubber bonded crank pulley? I've seen these begin to slip and not drive the belt. They get oil soaked and deteriorate. When you look at the running engine the fan will be turning but is it turning fast enough? Pulley will turn it and the generator at idle but not at 2500 RPM.

Hi Tommy,

Yes, I was going to start a new thread for this issue to clarify everything but it just sort of took off.

About 3 or 4 weeks prior to the current situation, the truck overheated and boiled out most of the coolant. It was a legitimate rolling boil in the recovery reservoir, not normal expansion and contraction of coolant.

After testing for head gasket leaks turned out negative, I decided to remove the radiator and water pump. Radiator showed signs of ancient leaks and maybe even current ones. Since the pump was off, it made sense to send it out to be rebuilt. Impeller fins on the front side of the pump looked pretty worn but there's differing opinion on that since the pump turns out to be an aftermarket replacement, albeit a very old one.

No undue crud was discovered during the flushing of the block with water. No chunks or sludge ran from the rear petcock or from the two holes for the water pump. At most, the water was slightly tinted brown - probably from surface rust that formed on the cast iron while it sat empty for 3 weeks. Who knows?

When I flushed the system after the initial overheating event, there was a small amout of rusty goop at the thermostat. The inside of the t stat housing was sort of rusty but not flaking off - just normal rusty cast iron.

When everything was re-assembled, I experienced the same symptoms and boil over as had occurred the first time.

Prior to all of this, the dash gauge stayed right at 180 give or take - even on hot days in rush hour traffic.

I will check the harmonic balancer to see if it has slipped on the rubber. Coincidentally this happened on the '66 Mustang last year. It squealed and I thought it was the water pump since I could make the sound when turning the fan by hand. When the belt was removed, the sound went away so I looked at the balancer and found the sheave sliding around the hub.

Another problem that has developed is that a crack on the driver side of the block that had been repaired many years ago by some previous owner has begun seeping pretty noticeably. I wonder if the high heat did something to the epoxy.

OInce I solve the overheating issue, what would be the best method to repair this? Do I have to grind all the old epoxy off? Whoever did it did a sloppy job and really pasted it on thick.

I just tried to turn the engine/balancer pulley by turning the fan by hand but neither the crank nor the pulley wanted to budge. It seems like the balancer is intact but I'll have to remove the belt to check further.

I wish I had looked at it closely when everything was taken apart and out of the way.

As for pulling the engine and removing core plugs, etc to clean the water galleries, that's not really feasible at the moment although I understand that might be the only way to clean out a blockage if one exists.

Unfortunately there is no movement at all between the sheave and hub on the vibration damper.

A Stovebolt harmonic balancer cannot slip. It is simply two round plates with a flat round rubber disk sandwiched between them.The two plates, the rubber disk, the crank snout and pulley are held together by numerous sturdy rivets. Even if you sheared all of those rivets, all that would happen is that the entire assembly would fall off into its many parts leaving you with just the snout left on the crank.

So not made like this one?