Running hot!

[71se3834v]

Jul 27, 2021 8:42:33 GMT -5 hanks73340 said:

By chance, did the 71's have heat risers on them? Had similar issues that you're having Jeff on my 71 Chrysler 300 a couple of years ago and it turned out that the heat riser was stuck because the spring broke on it.

Heat riser valve was eliminated and a block off valley pan was installed when the engine was rebuilt.

[71se3834v]

Jul 27, 2021 2:43:01 GMT -5 Nacho-RT74 said:

Jul 26, 2021 21:54:22 GMT -5 71se3834v said:

Well I'm guessing you know the 71 didn't have one. Ha! I was looking at that tonight to see how difficult it would be to install one.

Fan clutch... well, supposelly it should move more less freely when cold and dragging when hot. That's all what I know

You are on to something. I've read that the fan shouldn't turn more than 3 times when you shut off a hot engine. When I spun it (hot engine) it seemed to spin easy. Tonight on a cold engine I spun it and the first try it rotated a couple times then the next few times I tried it wouldn't even rotate a full turn. It shouldn't be engaged at cold temps. Seems inconsistent.
Bad clutch seems to be likely since it was heating up once at slow speeds. Will drive it to work tomorrow and see if the fan seems engaged when hot.

[Nacho-RT74]

Need to clarify, when cold IS NOT completelly free, but you can move it way easier than when is hot. On both stages will drag, but difference is noticeable betwen both.

[71se3834v]

You are correct. Hayden states clutch should rotate 20-30% of shaft speed at cold temp and 60-70% of shaft speed at hot temps.

[71se3834v]

Drove to work this morning. Temp low '70's. Within a mile temp was at 195* then I watched it drop to 180*. Seems like that means the thermostat is working. Five miles at 45 mph then highway 65-70 for 6 miles. AC not on, temp ran 195 then peaked at a tick over 200* on the highway.
On the way home outside temp at 86* and 51% humidity. Highway driving at first where temp peaked at 205 then hit 210* when I got off the highway and came to a stop. Upon driving the rest of the way at 45-50 mph it dropped and stayed at 205*. Once home I watched the fan when shutting off and it seemed to continue to spin 2-3 times before coming to a stop. When spinning by hand it would rotate a couple times then the more I spun it the stiffer it became.
I think I'll be replacing the fan clutch and while I'm at it I always wanted to install a fail safe thermostat to protect the numbers matching engine. Ugh! More work to do.

[71se3834v]

Fan clutch was bad. The shaft coming out the front that the thermo coil is attached to was loose and oil leaking out of it. That was one of the symptoms that Hayden listed. I could feel it loose when it was still on the car. Once it was off I could see oil leaking out the back also. Now I know where the splatters I seen on the fan were from. Installed a new fail safe thermostat also. Not what I was expecting as I thought the fail safes "fail" in a way that they stayed open. I've had one fail and stay closed so that was what I was looking for. Info states that if overheating occurs it will "lock" open so maximum circulation happens.
Haven't driven the car yet but I'm confident this problem is solved. Now just have to solve my problem with the exhaust shop.

[71se3834v]

Forgot to add installed a new set of Mopar belts from my stash of stuff. All the belts, that were bought in 2011, were cracked.
Sometimes things are blessings in disguise. I have been feeling pretty run down with all the repairs this year along with being overwhelmed at work. But the bright side is these things could have reared their ugly head on the up coming trip this Sept. Engine overheating, power steering hose leaking or belts breaking are NOT needed on a road trip.

[DynoDave]

Good point. If we get hot weather for Frankenmuth, and you are stuck idling in line waiting to get in, you don't need overheating or belts issues.

[71se3834v]

Ran it up to the exhaust shop. Wasn't paying attention to it but when I picked it up today and ran it the 4 miles home with air on and outside temp at 82* it barely got over 160*. Let it idle a bit and final temp was 165. Fan stopped spinning the moment I shut it off. Hand spun it and it doesn't spin even a half turn. At least now the fan should be spinning properly. Strange though the temp was so low. Maybe the old thermostat was opening too soon? Same temp rating 180*. Got to run it longer but there's more work to be done and no time for driving. A/C didn't seem to be blowing as cold.

[Admin]

Aug 12, 2021 21:03:09 GMT -5 71se3834v said:

A/C didn't seem to be blowing as cold.

That's curious. With the viscous fan now working better / pulling more air, you would think the a/c would work a little better, at leats at idle and low speeds where the fan has the biggest effect.