351C Running Hot - Page 2

Chifo Jr · #21 (**permalink**) 07-21-2003, 01:58 PM

Yes its in there but I am considering using the plug and replacing the t-stat with a conventional style.

rdorman · #22 (**permalink**) 07-21-2003, 02:25 PM

Sorry, redundant question.

I find it very interesting that you able to go through break in with out overheating. Also find it interesting that at 220 degrees it is puking into the recovery tank.

I know water boils at 212, 50/50 anti-freeze raises that to about 223 and with a fifteen pound cap that raises it to about 270 or so (even over about 240 with a 7 pound cap). So if the 220 is accurate, why is it puking? That does lend to the head gasket theory(hot spots) but then why did it not happen when you broke the motor in?

Have you tested the cap and its seat as mentioned earlier? If the gauge is correct and the system pressurized then it should not boil over at 220. I would pressure test the system and the cap as well as verify that the cap is seated properly before I went to all the trouble of pulling the heads.

Do you have an infrared thermometer (or something suitable) or have access to one and can measure the heads at various locations to see if they are being evenly cooled? I would think the head gasket problem would show itself this way. Any one checked in this fashion?

Rick

Chifo Jr · #23 (**permalink**) 07-21-2003, 02:38 PM

Redundancy is good! I am going to take it in to a radiator specialist in hopes that he can find a definative problem. The motor does only have a few hours on it.

niles · #24 (**permalink**) 07-21-2003, 05:47 PM

CHI:

Reread Rdor and niles.

Chifo Jr · #25 (**permalink**) 07-21-2003, 05:51 PM

Were you overheating as well? I am getting up to 230 to 240 on the gauge for a very breif period!

niles · #26 (**permalink**) 07-21-2003, 06:13 PM

.It depends where your sender is located. Mine is in the water pump housing; thus my guage never showed a high reading.
The boiling occurs in the head/thermostat area and the water expands and a large bubble occurs in that area, you can hear gurgling and boiling sounds in that area.

Check you pressure cap!!! If working right you shouldnt be boiling and punking unless something is serioulsy amiss. You need a pressurized system and a good purging of all air; if you have air trapped anywhere you get those symtoms

gn

Chifo Jr · #27 (**permalink**) 07-21-2003, 06:33 PM

Niles, How did ou purge your system? What is your design for filling? My sender is in the block..

pnkrugby · #28 (**permalink**) 07-21-2003, 06:51 PM

i have a 4v cleveland and am considering building a cobra for it. sounds funny doesn't it? would you recommend this? i've heard they like to run hot and cobras aren't the best breathers.

rdorman · #29 (**permalink**) 07-22-2003, 06:51 AM

Do you have a closed system Chifo? My system does a pretty darn good job of purging air all by itself. In the warmer months I run nothing but distilled water and water wetter.

The car did run hot on occasion last summer at DVSFII. I flushed the system (ran super flush in it for days), drained the system, filled with water wetter and distilled water. With the fill cap off and engine running I continued to fill the system until the thermostat opened (I also measured the water temperature at that point to see that the thermostat was opening at the correct temperature. Even if it says 180, it may not open at that temperature. This is certainly easier than removing it to test. My system fill point is just inches downstream from the thermostat), replaced the cap and shut it down. I then completely filled the recovery tank and checked the level occasionally over the next several days. I could see that the system pulled in a little more water each time I drove it, then the level stabilized. I am not saying this will help you, but it was all I needed to do.

Oh, I also set the fan temp at the same time I was checking the thermostat and filling the system. Before I started it I turned the adjustment to the higher temperature. I verified that the thermostat opened at 180, let the temperature rise to above 190 and then adjusted the fan to kick in at that temperature.

I would still pressure check the system, ensure the cap is sealing well, test the cap, thermostat opening temperature, fan start up temperature and polarity. If all that is good, measure the head temperature at various location, writing it down, to check for even cooling. Realize of course that the temperature will vary at different locations but look for consistancy. If the head temp near the exhaust port is the same across the board, great, if not....... . While you are checking temperatures, you might check the header temp of each pipe, especially as the problem occurs, to see if you might have a fuel issue.

Running lean at cruise may fit your issue. As would timing.

If not, head pulling time!

I am eager to hear how you resolve the issue so please keep us informed!

Rick

Chifo Jr · #30 (**permalink**) 07-22-2003, 10:22 AM

I really appreciate your help in resolving this problem. I am under the gun so to speak with registration of my car and the DMV has given me only a 30 day extension so time is precious. My system is a closed type system in that the upper line runs from the t-stat housing about 8 inches to a t style fill cap. Then it runs to the top of the radiator and back to the water pump inlet. I have an overflow tank which is plumber to the bypass hose fitting on the t filler. I have a short "u" shaped tube that runs from the water pump fitting into the pressed fitting back into the block. Is this correct? My next step will be to have the cap checked. One note is that when I ran the car with the cap off, the coolant seemed to be pressurized and was flowing out of the top of the filler neck. I did place a thermometer in the coolant and verified that the temp was above 195. I did also check the t-stat in a pan of water and it did open at 180. I'll keep you informed. And thanks again.

LimoDave · #31 (**permalink**) 06-10-2020, 03:58 PM

Hello Fellow Cobra Lovers. I just registered myself to this Forum. I'm s new owner of a Replica of a 1968 Shelby Cobra. I've read many posts and replies about the motor overheat issues. I currently have the same, I followed the suggestions that were listed. My motor does have the brass blocking plate in the block but the thermostat was not for the Cleveland motor. No idea if it in fact was a Windsor thermostat or not. Nonetheless, after I bought the car, I trailered it home from South Carolina. I drove it with little overheating during the drive. That's when I read some posts to get the idea of the thermostat. I believe I got the right thermostat and tried driving it to check my problem of overheat. Yes in fact it did overheat. More than it did the first time I drove it. I then began to go through the coolant components and I'm no mechanic but I do know something about cars and the basics. Brakes, tuneups, coolant flush, etc. Nothing serious though. So I've found components I have no idea why it is installed on my car or what it is expected to do except taking up fender wall space on the passenger side in the motor compartment. Does anyone have any idea what the components are for a Ford 351C? Please help.

krausewich · #32 (**permalink**) 06-10-2020, 10:47 PM

Hi Limo Dave,
Start a new post about your car with specific items/pics when you can... Make, year, and info may help.

I too purchased a Cleveland car that was known for having overheating issues. It does seem to have the Windsor thermostat, and parts places that I've looked up and purchased from seem to offer the same Windsor style thermostat as a replacement on the Cleveland!! Did every Cleveland overheat? I can't imagine of the hundreds of thousands of engines produced, that there wasn't a reliable solution. There are a few different thermostat and restrictor washer combinations out there. Not sure which if any are the end-all solution, but the stub on the thermostat should be large enough to plug the hole in the restrictor when at temp. When I get it right, I will be sure to share!!