Hot Under-Hood Temps

[Big Red Mach 1]

Then I drained the radiator down some and investigated the T-Stat and checked for the plate. T-Stat was a 180 Degree. I'm replacing with a 192. The plate was there, and in good overall shape so I left it in vs. destroying it getting it out. So the T-Meyer T-Stat will go in, and the factory plate will remain.  

 

[Big Red Mach 1]

Have do do multiple posts to add enough photos. I liked the old site better for adding photos. 

 

[Big Red Mach 1]

Here's the inside of the radiator. I have a 3 row Champion that will be replacing this tomorrow. Question is, is this OEM radiator worth cleaning out and saving? It doesn't really overheat or leak. Just probably doesn't flow the best. 

 

[Kilgon]

If it is not leaking and was holding pressure I would hang onto it.  If you have a local radiator shop close by you could have them clean it out before putting it away.  Someone doing concours may be interested in it. 

 

[Carolina_Mountain_Mustangs]

I run a stock radiator and have not had over heat issue. 351 C bored .050" flat top pistons, cam, headers, <MSD, auto and AC. You can put CLR mixed with water in the radiator and dissolve the crust in there. That build up comes from not using distilled water in radiator. Good you kept the Ford baffle no reason to change. I see more backward head gaskets causing issue the baffle worked and still works. 

 

[Big Red Mach 1]

So first time really driving the car for the first time in a long time. Went up the road 5ish miles to a neighborhood cars and Coffee thing. Even though the gauge never went beyond where it normally goes, it puked a bit of coolant. Did it when I got home too. There was some sludge in the new radiator. When I changed the radiator, and T-Stat I used distilled and new coolant, but I did not flush the block or replace the water pump. Hoping the sludge is just old gunk from the water pump/block, etc. just being broken free. But still it did puke for the first time ever. 

I've had people with Clevelands in hotter climates like Florida, Texas and Arizona, to not ever bother using a T-Stat. That the car will run 15-20 degrees cooler without one, and it will flow a lot better too. I would never do that on a newer computer controlled car, but I guess I can see that logic on an old carbureted car. Anyone else in the hot climates doing that? 

 

[Carolina_Mountain_Mustangs]

Running any engine without a thermostat will make it run hot not cooler. Anyone saying otherwise has never done it. If you have no restriction the water just gushes through the system and does not spend enough time in the radiator to cool. The hotter the thermostat you use in hot weather the less chance you have of over heating. 
I have not read your whole post. From what I see here I would do a exhaust gas in coolant check. Most parts houses will loan if you buy the solution. 
The symptom you have of it blowing out coolant when you stop tells me you have a hot spot somewhere and when you shut off engine that hot spot boils the coolant and blows it out. If you have had the heads off I would be suspect of a backward head gasket. I think you have a Cleveland which does not have core plugs in the end of the head that you can pop out to check. You can look with a mirror. The front bottom corner on the gasket is square with a small radius. The rear has a large radius and then angle. If you do not have the baffle in the block under the thermostat that can be an issue also. I have eight Clevelands and only one that ever had an issue the PO had put one head gasket on backwards. He did not drive it for 25 years and I bought it and found the backwards gasket. Replaced and you can drive in 90 deg. + bumper to bumper traffic with 195 deg. thermostat and no heating issues. It is bored .050" over cam, flat top pistons, automatic and MSD ignition with 2-V heads and 4-V performer intake so not stock. The radiator is stock original Ford. I did put a stand alone transmission cooler on. Here is pic of a cleveland head gasket note the difference from end to end. If on backwards there is not much flow of coolant in head. You turn engine off and the hot spot in head percolates the coolant and blows out. The gasket picture would by like it would be on drivers side see the big hole in the left hand tab that needs to be in front on the passenger side also. Get a mirror and check your gaskets. 

 

[Don C]

+1 on do not run without a thermostat, especially in hot climates. The thermostat provides enough restriction in the water flow so the coolant has time to absorb heat in the block and then transfer the heat to the air in the radiator. 

You may have overfilled the radiator. When you shut the engine off all of that engine heat transfers into the coolant in the block, may even cause some of it to boil, expanding the coolant and causing some to burp out.

 

[Big Red Mach 1]

Took a mirror to the back of the head, driver's side back by the brake booster. I noticed a visible gap between the head and the block that I can only assume is due to the taper of the gasket on that end. So I believe it's on correct. 

That's what I've always known about the t-stats also. That the higher temp T-Stats actually raise the boiling point and are actually beneficial. That's why I asked instead of just taking the 5 minutes to lower the fluid level and pulling it out. I have heard that drilling a tiny pilot hole in the t-stat can help it bleed out any air better. I did go from a 180* to a 192*. I should note that it never puked on the 180* but it did with this 192*. BUT I definitely could have overfilled it. I only had the fluid bout 1" down from the top, and maybe that wasn't quite enough for expansion. 

I'll let her idle up to temp and take some readings in different spots with the laser thermometer. I"ll try to grab temps from the T-Stat housing, water pump at the temp sender, at the exhaust ports of the heads at all 8 cylinders, and around the radiator in different spots. Anywhere else you guys can think of that would be good?

I know my lower hose does NOT have a spring in it. It is new though. 

I'd like to hook up a new gauge to the temp sender, just to see how much it differs from the stock gauge. I'm assuming that just about an aftermarket gauge will work as I don't intend to mount it. 

 

[Carolina_Mountain_Mustangs]

Yes drill a 1/32" dia. hole in thermostat out near where the gasket goes. Just lets the air out of block while filling and not going to affect flow. Some thermostats come with the hole in them.
So sounds like your gaskets are right. On the right hand head you can run a wire from the thermostat opening up into the head to where the big round hole is and double check gasket also. I make a habit to taking pic just before head goes on. 

 

[Stanglover]

I'm just getting back to this post. I re-read through and I know you're a mechanic which I'm far from, but I have to wonder if you don't have air trapped in the block somewhere. I found they are not the best to get air out of, but what I do if to fill without the T stat or the hosing in place. I have in the past, remove the pump belt and turned the pump by hand to help get water moving. Does this do anything, not sure, but can't hurt. Once the water is right up in the T stat hole, then put the stat back in and install the housing and rad hose. Fill the rad and start the motor for a short time, checking the flow, no cap on Rad. Is this correct, I don't know, but I've never had an issue with overheating as you describe. I have a Stant 195* in mine and it runs around 190 on a hot day. The only time I've seen it higher was last summer on the way back from the Mustang show in Dearborn Mi, when I got stuck at the border for a 1/2 hr. Revving the motor, pissing off those around me, got the temp back down below 200. Had to do that a couple of times. Once moving again, back to normal.

As for headers, I don't have them on this car, but the 72 Q I had, the floor got soo hot, it would almost melt your shoes, no, there was no insulation.

 

[Jeff73Mach1]

I'm late to the party, so please forgive me if this has been mentioned.  Have you replaced your Radiator cap?  Radiators rely upon pressure to assist in the cooling process.  If it is older, it may be time for a fresh cap.

Lower hoses shound have springs in them to prevent collapse.  If this is occurring, nothing but a new hose will fix the system.

As to the remaining gunk in your coolant,  I would flush the system repeatedly with clean water until it drains clean then flush with a few gallons of distilled water before refilling it with the proper coolant/mix.  Pure anti freeze doesn't cool as well as a 50-50 mix (unless you are using one of the modern prediluted mixtures.)

I'm running a close to 600 HP 393 stroker bored 30 over with a high volume water pump and a griffin aluminum radiator and I have not experienced the heating issues you have . . . and I have AC on the car.

After filling a cooling system, it should puke once or twice down to the proper level, it is the repeated puking that would worry me.

I've never bothered with the exhaust crossovers on an aftermarket intake-it seems to be unnecessary

 

[Big Red Mach 1]

I'm just getting back to this post. I re-read through and I know you're a mechanic which I'm far from, but I have to wonder if you don't have air trapped in the block somewhere. I found they are not the best to get air out of, but what I do if to fill without the T stat or the hosing in place. I have in the past, remove the pump belt and turned the pump by hand to help get water moving. Does this do anything, not sure, but can't hurt. Once the water is right up in the T stat hole, then put the stat back in and install the housing and rad hose. Fill the rad and start the motor for a short time, checking the flow, no cap on Rad. Is this correct, I don't know, but I've never had an issue with overheating as you describe. I have a Stant 195* in mine and it runs around 190 on a hot day. The only time I've seen it higher was last summer on the way back from the Mustang show in Dearborn Mi, when I got stuck at the border for a 1/2 hr. Revving the motor, pissing off those around me, got the temp back down below 200. Had to do that a couple of times. Once moving again, back to normal.

As for headers, I don't have them on this car, but the 72 Q I had, the floor got soo hot, it would almost melt your shoes, no, there was no insulation.

I thought about vapor lock. It's certainly a possibility. I do like your idea of slowly filling the block up to the t-stat hole, and then installing the T-Stat/Housing/Upper hose and filling the rest of the way. I'll probably do that the next time I have to drain it down. That's for that great idea Geoff.  

 

[Big Red Mach 1]

I'm late to the party, so please forgive me if this has been mentioned.  Have you replaced your Radiator cap?  Radiators rely upon pressure to assist in the cooling process.  If it is older, it may be time for a fresh cap.

Lower hoses shound have springs in them to prevent collapse.  If this is occurring, nothing but a new hose will fix the system.

As to the remaining gunk in your coolant,  I would flush the system repeatedly with clean water until it drains clean then flush with a few gallons of distilled water before refilling it with the proper coolant/mix.  Pure anti freeze doesn't cool as well as a 50-50 mix (unless you are using one of the modern prediluted mixtures.)

I'm running a close to 600 HP 393 stroker bored 30 over with a high volume water pump and a griffin aluminum radiator and I have not experienced the heating issues you have . . . and I have AC on the car.

After filling a cooling system, it should puke once or twice down to the proper level, it is the repeated puking that would worry me.

I've never bothered with the exhaust crossovers on an aftermarket intake-it seems to be unnecessary

So the upper and lower hoses are new (New lower hoses does not have a spring), T-Stat new (went from 180 to 192) new radiator and new cap. I thought about the cap and actually swapped to a different one, even though I have not driven the car again since. But I did wonder about a bad cap. I am hoping it did just as you suggested, puked down once or twice to the proper level. I very well may have had it filled a bit too high. 

 

[Stanglover]

I thought about vapor lock. It's certainly a possibility. I do like your idea of slowly filling the block up to the t-stat hole, and then installing the T-Stat/Housing/Upper hose and filling the rest of the way. I'll probably do that the next time I have to drain it down. That's for that great idea Geoff.  

You might also want to raise the front a little to assist the air moving from the back of the block. I think you'd be safe, once the block is full, to run the engine a short time just to get the water moving, but that could get messy! A PITA for sure.

 

[Big Red Mach 1]

You might also want to raise the front a little to assist the air moving from the back of the block. I think you'd be safe, once the block is full, to run the engine a short time just to get the water moving, but that could get messy! A PITA for sure.

Yeah, I doubt I start it at that point. But I do like the idea of filling it to that point in that manner. 

 

[Stanglover]

Yeah, I doubt I start it at that point. But I do like the idea of filling it to that point in that manner. 

I've had to redo mine about 4 times now that way and not run the motor until it's all back together, but on second thoughts, may not be such a good idea to run the motor, water all over the place.   Possibly just crank it?

 

[Jeff73Mach1]

We put the radiator for a frineds vehicle in the trunk and used exhaust pipe to run the water lines.  You want to try and get air out of a system, that one will give you nightmares.

 

[69 Rustang]

Interesting thread.  The part about checking the timing cover plate was interesting as I have seen them in really bad condition in the past, but wouldn’t that put coolant into the oil (Something I would see)?  

Despite my recent post on overheating, historically I have never had overheating problems with a 351C, in fact they seem to run cool on the cars I have owned.  I haven’t had time to fully figure out what is going on with my ‘69 right now, but I did confirm the thermostat is opening properly.  I bought a new one anyway and drilled a small hole as instructed in this thread.  My next step is to do the combustion gas leak test.  If that goes OK I am going to pull the water pump to see if something is going on there.  If the head gasket is leaking I told my wife I am buying either a stroker motor or I am going to swap in a late model 5.0.   She just grumbled a bit, not enough to deter me.  A true win-win-win scenario other than my checking account balance.

 

[Big Red Mach 1]

Interesting thread.  The part about checking the timing cover plate was interesting as I have seen them in really bad condition in the past, but wouldn’t that put coolant into the oil (Something I would see)?  

Despite my recent post on overheating, historically I have never had overheating problems with a 351C, in fact they seem to run cool on the cars I have owned.  I haven’t had time to fully figure out what is going on with my ‘69 right now, but I did confirm the thermostat is opening properly.  I bought a new one anyway and drilled a small hole as instructed in this thread.  My next step is to do the combustion gas leak test.  If that goes OK I am going to pull the water pump to see if something is going on there.  If the head gasket is leaking I told my wife I am buying either a stroker motor or I am going to swap in a late model 5.0.   She just grumbled a bit, not enough to deter me.  A true win-win-win scenario other than my checking account balance.

I feel like I'm in the same spot. I have the water pump. Have not put it on. I also have the test kit coming to see if I have any combustion gasses in the cooling system. If the test comes back negative, I'll do the water pump and timing cover next.