FE Thermostat

[KevinW]

Pretty sure my thermostat is either permanently open, or opens too quick. Not an issue in the summer, but I would like it to stay shut while the engine heats up for winter driving.

Any suggestions for a good quality replacement?
Even better if its easily available internationally - don't really want to pay international freight charges on such a tiny item.

[patrickt]

Did you test in a pot of water on the stove or are you just guessing?

[1985 CCX]

Just std unit, not sure its a HP part.

[Grubby]

I am pretty sure the 428 thermostats are unique to Ford and Chrysler big blocks, and would not be easily available in Europe.

Also, beware there are two diameters of Ford big block thermostats.

John

[Sawdust]

Originally Posted by KevinW

Pretty sure my thermostat is either permanently open, or opens too quick. Not an issue in the summer, but I would like it to stay shut while the engine heats up for winter driving.

Any suggestions for a good quality replacement?
Even better if its easily available internationally - don't really want to pay international freight charges on such a tiny item.

Cobra Valley, Performance Unlimited Automotive Center - West Bend, Wisconsin - USA Main Lobby

[sunman]

Stant Superstat Premium Stainless Steel about $20-30.
Good stuff. Amazon, Pepboys, Ebay, you might have to shop around Summit is backordered.

[undy]

Originally Posted by Grubby

I am pretty sure the 428 thermostats are unique to Ford and Chrysler big blocks, and would not be easily available in Europe.

Also, beware there are two diameters of Ford big block thermostats.

John

Yes, I think up to 1965 it was the large diameter thermostat and later years used the smaller diameter. I could be one off or so on the transition year. The OP needs to pull it and measure the diameter then determine large or small diameter before he orders one. It's actually determined by the intake age or the age that the reproduction intake mimicked (like mine).

This was a bit of a headache for me when installing my KC 482" Pond side-oiler. I was running a Dove "leak-o-matic" Tunnel Wedge intake and it took the large diameter stat.

[Grubby]

Undy,

I had the same problem on my Lykins FE build.

John

[55312]

This is where I get mine.

Cobra Valley's Balanced Thermostats

Tim

[RockBit]

I started off with a Stant thermostat, which crapped out pretty quickly. I installed another Stant and it did not work well. I the went to a Flowkooler Robertshaw type and it has worked well.

[MaSnaka]

I use what NAPA has for the FE390. I believe its a Stant. 190 degree F. which is the stock T-stat. I drill a 1/8" hole on the flange and orient the hole to the top to help purge any air that might get trapped. I do live in southern California where driving days are 40-50*F at the low.

John

[Dominik]

Perhaps try https://cobracorner.de in Germany. Try whatsapp text. While his parts also came from the US, he orders often enough to have reasonable markups. A FE specialists since 30+ winters. Possibly the quickest (RAM) Cobra around. Someone placed his Cobra on Wikipedia.

[patrickt]

It's probably not even a Thermostat issue. Until you pop it out and put it on the stove in a pot of water and a candy thermometer you're really just guessing. And apparently KevinW hasn't touched base on his posting to let us know....

[KevinW]

Yes, you're right, I got a little distracted with the day job. But thank you all for your posts! I'll be looking into those suggestions.
My FE uses an Edelbrock dual plane Performer(I think) intake manifold, so I think its the large size thermostat?

I did try out the thermostat in hot water and it did seem to work OK prior to installation a few years a go. I then read an article telling me this was exactly the wrong thing to do, so this put some doubts in my mind.

My reason for thinking it may be faulty:

1. Top hose on my FE gets pretty hot pretty quickly;
2. Winter driving yesterday (air temps 32-39F): engine temperature only seems to get up to 70C/158F, frequently down to 65C/149F when cruising at 60mph+ in top gear (around 2.5-3k revs).

On the last point, I thought the stat should only open when the engine coolant temperature is up to normal operating point, which I have assumed is 85C/185F (well that's where it was in the summer, maybe a little more when weather reached 100F in the sun), and then should start to close if the coolant temperature fell. Happy to be corrected if my understanding is wrong.

Retracing my thoughts aloud, I guess I need to first (a) put some kind of insulated shield around the manifold temp sensor to see if cool air is effecting it, and see how warm the rad gets - wasn't enough to switch on the fans yesterday.

[patrickt]

Originally Posted by KevinW

Happy to be corrected if my understanding is wrong.

Do this: When your new thermostat comes, take your old thermostat out of the car and test them both at the same time in the same pot of water. That will give you a nice definitive answer as to opening points on your old and new part and it will also tell you whether your old thermostat was misbehaving. Then, assuming the new thermostat behaves differently in the pot than your old, you can decide which one you want to put back in the car. But, since you have to take the old part out to put the new part in, it would be kind of stupid not to take the opportunity to test them both.

[KevinW]

Originally Posted by patrickt

Do this: When your new thermostat comes, take your old thermostat out of the car and test them both at the same time in the same pot of water. That will give you a nice definitive answer as to opening points on your old and new part and it will also tell you whether your old thermostat was misbehaving. Then, assuming the new thermostat behaves differently in the pot than your old, you can decide which one you want to put back in the car. But, since you have to take the old part out to put the new part in, it would be kind of stupid not to take the opportunity to test them both.

Thanks Patrick, good idea.

[davids2toys]

Originally Posted by 55312

This is where I get mine.

Cobra Valley's Balanced Thermostats

Tim

This looks like a pretty wild thermostat and quite an upgrade, but is it beneficial in a regular street 428? I would do it if the answer is yes and why. I am getting ready to do a gasket update on the front of my motor because of oil leaks and slight water pump gasket leak. Also need to install ta new balancer. Also new valve covers and oil pan. I dont know what T-stat in presently installed but I have no issues. i figure I'm in there anyway, so change the coolant and t-stat. I replaced my old Cobra T-stat with a Stant Superstat 532030 and had no issues up until I sold the car (7 years).

[eschaider]

At nearly $40 it's not only wild looking, the pricing is rather impressive also.

[davids2toys]

Agreed, but would do it if provided good reason and advantages. I do see some advantages in their advertisement on the site, but I rather here it from the experts/customers in this forum

[Michael C Henry]

What I saw and did. My car came with a jerry rigged thermostat. It was a GM thermostat with a large valve glued in a Ford FE outer ring that fit the FE thermostat socket. I found a Chrysler thermostat that had a large valve in a large diameter body that fits the large FE thermostat socket. I'm sure that you can find them in all temps and will fail in open position.