Radiator Experts Please Step In

[SierraMtns]

I am looking for some help with my cooling system on my 67 stepper. I replaced the 160* thermostat with a 180* one a couple days ago. With the 160* one the temp gauge wound not come off cold. It would move a hair but stay in the cold area. Now with the 180* thermostat the temp gauge comes off cold maybe 1/8" in to the normal range area. The whole system only has 350 miles on it.

But now I am getting water coming out of the overflow tube. I don't have an overflow reservoir to catch the antifreeze. The cap is rated at 13 lbs. Here are my questions.

1. Should I change to a cap that is rated at 15 lbs?

2. What kind of overflow reservoir should I get? I would like to make the system a closed system.

3. How should I set my dual fans? Once it gets to normal temp, let the 2nd fan kick on? The driver side fan runs as soon as the truck is started. The passenger one has a nob to adjust when it kicks on.

Pictures.









Thanks for the help.

[trac209]

Your going to need a catch can inless you like topping up the system regularly. Increasing the cap pressure won't stop excess pressure from pushing past the cap. A reservoir with a vent is needed for proper operation.

[haysonj]

You need some kind of control on the first fan. My duel fans have a temp probe in the radiator fins. The first fan does not come on until 195 degrees and the second comes on at 210. The second one also runs when the AC is turned on. I have a 195 thermostat and my truck never goes over 210 and that is towing in 100 degree heat

[SierraMtns]

Originally Posted by haysonj

You need some kind of control on the first fan. My duel fans have a temp probe in the radiator fins. The first fan does not come on until 195 degrees and the second comes on at 210. The second one also runs when the AC is turned on. I have a 195 thermostat and my truck never goes over 210 and that is towing in 100 degree heat

Yeah have looked all over the fans to see if I can adjust the 1st fan to not come on until the truck warms up. Cant seem to find anything. Any idea where to look guys?

Also can someone recommend a overflow reservoir to make it a closed system.

[cdowns]

if you fill it to the top when cold it is normaal for you to lose some out the overflow when it gets to normal operating temp// solutin isd do=nt fill to the top

did you take a known good thermometer and take the temp to see how far that 40year old gauge is off

[SierraMtns]

Originally Posted by haysonj

You need some kind of control on the first fan. My duel fans have a temp probe in the radiator fins. The first fan does not come on until 195 degrees and the second comes on at 210. The second one also runs when the AC is turned on. I have a 195 thermostat and my truck never goes over 210 and that is towing in 100 degree heat

Originally Posted by cdowns

if you fill it to the top when cold it is normaal for you to lose some out the overflow when it gets to normal operating temp// solutin isd do=nt fill to the top

did you take a known good thermometer and take the temp to see how far that 40year old gauge is off

No I didn't check the meter because I was told they where all new meters.

[engineer_gregh]

I'm running a Griffin aluminum radiator with dual electric fans. My first suggestion would be to call Jegs or Summit and order a relay kit with temp sensor that controls when the fans come on and off. If your fans are moving a lot of air it makes it difficult for the engine to come to temp. Mine kicks on at 185 and off at 170. Second look at LMC for the overflow bottle. Here are a couple of examples. Hope this helps.

http://www.jegs.com/i/JEGS-Performan...ductId=1557724
http://www.lmctruck.com/icatalog/cb/full.aspx?Page=63

[SierraMtns]

Originally Posted by engineer_gregh

I'm running a Griffin aluminum radiator with dual electric fans. My first suggestion would be to call Jegs or Summit and order a relay kit with temp sensor that controls when the fans come on and off. If your fans are moving a lot of air it makes it difficult for the engine to come to temp. Mine kicks on at 185 and off at 170. Second look at LMC for the overflow bottle. Here are a couple of examples. Hope this helps.

http://www.jegs.com/i/JEGS-Performan...ductId=1557724
http://www.lmctruck.com/icatalog/cb/full.aspx?Page=63

WOW...those relay kits are not cheap.

What is wrong with letting the 1st fan to run all the time? Didn't the OEM manual fan run all the time? I do like the idea of the relay set-up since these fans are so loud. My wife says it sounds like a jet boat. lol

[engineer_gregh]

I've attached a couple of pictures of mine with the overflow bottle. One problem with the electric fan(s) running all the time is the amount of current they pull from the electrical system. I upgraded the alternator to 100 amp as the stock one couldn't keep up. I found myself stranded needing a jump start; a/c, dual electric fans, and amp for stereo was just too much. No problems since upgrading the charging system. Another problem is operating the engine at really cool temps, i.e. <160 degrees; poor idle and worse than normal gas mileage. Just my .02 cents. I would shop the relays on ebay and such, as I think you can find them much cheaper than Summit or Jegs.

[SierraMtns]

Originally Posted by engineer_gregh

I'm running a Griffin aluminum radiator with dual electric fans. My first suggestion would be to call Jegs or Summit and order a relay kit with temp sensor that controls when the fans come on and off. If your fans are moving a lot of air it makes it difficult for the engine to come to temp. Mine kicks on at 185 and off at 170. Second look at LMC for the overflow bottle. Here are a couple of examples. Hope this helps.

http://www.jegs.com/i/JEGS-Performan...ductId=1557724
http://www.lmctruck.com/icatalog/cb/full.aspx?Page=63

Originally Posted by engineer_gregh

I've attached a couple of pictures of mine with the overflow bottle. One problem with the electric fan(s) running all the time is the amount of current they pull from the electrical system. I upgraded the alternator to 100 amp as the stock one couldn't keep up. I found myself stranded needing a jump start; a/c, dual electric fans, and amp for stereo was just too much. No problems since upgrading the charging system. Another problem is operating the engine at really cool temps, i.e. <160 degrees; poor idle and worse than normal gas mileage. Just my .02 cents. I would shop the relays on ebay and such, as I think you can find them much cheaper than Summit or Jegs.

Cool thank you sir for the help.

Where did you get the overflow tank from?

[engineer_gregh]

LMC, the link was in a previous reply.

[davepl]

Originally Posted by trac209

Your going to need a catch can inless you like topping up the system regularly. Increasing the cap pressure won't stop excess pressure from pushing past the cap. A reservoir with a vent is needed for proper operation.

The factory didn't seem to think so, did they? Not that a catch can is a bad idea (also mandatory at the track, if it matters). They should not puke coolant when operating properly.

Also, increasing the pressure rating of the cap most certainly can stop "excess" pressure forcing liquid out - but only if that excess pressure is below the cap's regulator spring. If you had 14psi of pressure in the system a 13psi cap will leak and a 15psi will not (that's the general theory, it's likely not precise to within 1psi in real life).

I've come to quite appreciate the Stant pressure tester I bought. It tests caps and rads and I've found a ton of leaks and one defective cap in the last year, so it's paid for itself.

On the fans, I would recommend getting two different sensors. One can go in each head if you don't have enough open ports on the intake.

If you have a 180F thermostat I'd have the first fan kick in at 180F and the other kick in at 200F. So you'd buy 180 and 200 sensors (Summit has them, BeCool also lists them).

If you only wanted one sensor and were OK with the fan running for no reason all the time, you could just get one that kicked in at 200. But you'll have less electrical load and noise with both sensors.

[davepl]

Also, if you wanted to get really fancy you could also probably buy a PWM (pulse width modulation) controller that runs the fans at a speed relative to the temperature. You'd have to check that your fan motor is ok with PWM. That operates by turning the fan off and on multiple times a second (like 100) so it runs at the desired speed.