Where to put mechanical temp sensor

[LocuMob]

Where can I put my temp sensor THROUGH the firewall in my 66 Polara? The hole that is below and to the side of the master cylinder isn't big enough without enlarging. Is there somewhere else that I might have missed? Is it possible to sneak it around my A/C hose outlets? Or too much of a PITA? Would like to know the temp, the car seems to be running a little hot. Nothing major, just gets a little warmer than I recall, of course I can hear it now with full exhaust this year.

Running a 440 with a .484 purple shaft, aftermarket aluminum water pump, Jeg's aluminum radiator (air does go over and under an inch each side, will be sealing that), electric fan pirated from a Bonneville (it was free after all), just put tti headers and full exhaust this year. Runs fine, slight pinging, the sound an engine makes when hot, not bad. Get it up to speed slowly and it's fine. Been turning on the fan for stopping and accelerating. Will be replacing thermostat just in case.

I run a lower ratio of coolant to water, if I had a cracked block from freezing, would it leak, and wouldn't it get hot very easily? I'm not thinking it's cracked, just wondering. I've had engines run completely out of coolant and that's not the case, plenty of light green stuff in the radiator. I don't beat on the car. Do accelerate briskly and stomp on it for a few seconds, spirited driving if you will. Think I gave all the details

 

[Wildaugust]

If a block was cracked, it may leak on the outside or it could show up as coolant getting into the oil pan. You also would likely notice that the oil level on the dipstick had risen mysteriously. That's what happened to a buddy's SBC anyway. I can't see the advantage to running weak coolant mixes. The antifreeze has rust inhibitors in it and it also is supposed to raise the boiling point of the coolant mixture. I always mix my coolant for -55 F, even if I don't drive the vehicle in winter. There are probably many different opinions on this subject though. I hope your block isn't cracked.

 

[LocuMob]

I talked to a friend who suggested I check my timing. Said it sounds too advanced, causing detonation. Sounds plausible to me. I'll check it after work tomorrow morning.

I run the weaker coolant mix only because I didn't have enough green stuff on hand when I was filling it up this spring, one of my full bottles turned out to be water. I have a temp gun I'm going to use to check the hoses after its warmed up to determine temp vs timing. After initial post I remembered thermostat worked fine when filling it up in March.

 

[Big_John]

I'm probably the only guy here that actually cracked a 440 block. I came home from the drag strip around 2 AM and forgot to drain the block... We had a surprise freeze (high 20's) and the block cracked. Long story short, it split down both sides of the lifter galley... Huge cracks.

So.. What I'm trying to tell you is there is no minor cracking from freezing... It's major.

 

[LocuMob]

I'm thinking it's not damaged. Runs too good.

Back to my original question, is there any holes on the firewall that would be available to put the temp sensor through, or is drilling a hole my only option? Need to drill a hole for my fan switch (on the dash) so I'll have my drill out anyways.

 

[Big_John]

Unless the 66 Polara is different from other Mopars of that vintage.... Look on the drivers side, near the steering column. There will be an oval shaped hole with a plastic plug in it. This is where they would put a clutch rod through if it had a manual. Poke a hole in the plug.

 

[LocuMob]

I'll check that out.

That's the ticket! I just wasn't looking down far enough. Should be an easy install tomorrow.

I did check the temp of the upper radiator hose when I got to work, the temp gun said 160℉ and the car had run for about 15 minutes driving and idling. Playing with timing tomorrow. Thanks guys.

 

[MrMoparCHP]

Unless the 66 Polara is different from other Mopars of that vintage.... Look on the drivers side, near the steering column. There will be an oval shaped hole with a plastic plug in it. This is where they would put a clutch rod through if it had a manual. Poke a hole in the plug.

I had thought about that but it may not be in a good location. I'm looking to put a mechanical oil pressure gauge on my CHP project and it will have a hard line not unlike the mechanical temp gauge. I haven't done it yet but I intend to drill a hole and run the tube through, as discrete as I can. I have use the clutch plug for wires before, just not sure it will work here.


Alan

 

[LocuMob]

It should work fine for me. The gauge is on the bottom of my dash under one of the ashtrays and I have plenty of wire to run it up to and over the engine. I didn't want to drill if I could avoid it.

 

[MrMoparCHP]

It should work fine for me. The gauge is on the bottom of my dash under one of the ashtrays and I have plenty of wire to run it up to and over the engine. I didn't want to drill if I could avoid it.

Good, the last mechanical water temp gauge I installed on a car had a rigid (coat hanger like) wire with a fixed length that might have been difficult to run that way.


Alan