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Radiator problems

  • Thread starter Thread starter steel1212
  • Start date Start date Aug 8, 2005
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steel1212

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Jun 24, 2004
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Frankfort, Ky
Aug 8, 2005
#1
  • Aug 8, 2005
  • #1
Ok, I just put high compression heads on my car, well high for me anyway. They are about 10.2:1 or so. I also put a victor series water pump on as well with a 3 row copper rad. Well now if I fill the rad to just above the first fins it spews out the over flow tube. Also it got maybe 210ish or a little below and the cap popped up and let out steam... I know I don't want to stay at 210 but it was just in traffic for a little while. Is there something I'm missing or do I just need an aluminum rad?
 

krash kendall

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Nov 19, 2004
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Aug 8, 2005
#2
  • Aug 8, 2005
  • #2
How many pounds is your cap? It also may still have air in the system. I just had the top my 3-row copper rad rebuilt and installed it last Thursday and it took several refills with the car running with the cap off to purge all the air.
 
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steel1212

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Aug 8, 2005
#3
  • Aug 8, 2005
  • #3
Crash I'm not really for sure how many pounds the cap is, I'll have to check. I didn't think about there being air in there from when I emptied it to change the heads....I'll look into that, thanks.
 
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ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
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BC Canada
Aug 8, 2005
#4
  • Aug 8, 2005
  • #4
This is normal.

The coolant expands when it gets warm and vents steam/coolant out of the cap. That's one of the reasons the cap is there.

If you do not have an overflow tank, it vents the coolant onto the road.

Get an overflow tank or just don't fill your rad to the top.

210 isn't bad for hot weather in traffic, but if it gets much more than that, it's time to start looking for other options.
 
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steel1212

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Aug 8, 2005
#5
  • Aug 8, 2005
  • #5
I was thinking of an overflow tank. What is the diffrence between the recirculating and just catch cans. I know one brings the fluid back but how?

Also a buddy of mine said that when we put the new heads on that it might not be sealing right and bleeding compression off into the water passage?
 

iskwezm

10 Year Member
May 24, 2005
4,159
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Rowland Heights,California
Aug 8, 2005
#6
  • Aug 8, 2005
  • #6
steel1212 said:
I was thinking of an overflow tank. What is the diffrence between the recirculating and just catch cans. I know one brings the fluid back but how?

Also a buddy of mine said that when we put the new heads on that it might not be sealing right and bleeding compression off into the water passage?
Click to expand...
As the syatem cools it creates a vaccume and sucks the coolant back in.

Get a exhaust gas dye(not proper name), it goes in the coolant and tell you if theres a head gasket problem.
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
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BC Canada
Aug 8, 2005
#7
  • Aug 8, 2005
  • #7
steel1212 said:
I was thinking of an overflow tank. What is the diffrence between the recirculating and just catch cans. I know one brings the fluid back but how?

Also a buddy of mine said that when we put the new heads on that it might not be sealing right and bleeding compression off into the water passage?
Click to expand...

Yes, a leaky headgasket will also blow coolant out of the radiator. But it is also normal for the coolant to expand and blow out of the cap when the radiator is hot and full to the top. The trick is to watch it.. if it doesn't blow out anymore coolant when it's down a couple of inches, then your probably fine. If it keeps blowing out coolant when your rad is 1/2full, then you have problems. A compression test is always good for finding head gasket problems.

As for the overflow tanks. The "catch can" style has the hose go to the top of the overflow tank/can and just fills the can.

The reciculating ones have a hose that connects to the bottom. It brings the coolant back because when the radiator/coolant cools down, it creates suction and "sucks" the coolant back out of the overflow tank into the radiator. Make sence?
 
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steel1212

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#8
  • Aug 8, 2005
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Perfect, thanks. I'm going to do a compression test probably tomorrow to check the heads, if thats ok I'm going to get a cheap recirculating one. Any suggestions on a good cheap one. I was looking at the one from Jegs and it looks like a good deal and matches my march pulleys and pump

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=498788&prmenbr=361
 
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ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
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BC Canada
Aug 9, 2005
#9
  • Aug 9, 2005
  • #9
steel1212 said:
Perfect, thanks. I'm going to do a compression test probably tomorrow to check the heads, if thats ok I'm going to get a cheap recirculating one. Any suggestions on a good cheap one. I was looking at the one from Jegs and it looks like a good deal and matches my march pulleys and pump

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=498788&prmenbr=361
Click to expand...


Something like that one will work great.
 

iskwezm

10 Year Member
May 24, 2005
4,159
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Rowland Heights,California
Aug 9, 2005
#10
  • Aug 9, 2005
  • #10
i got a stainless for less at the swap meet
 
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steel1212

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Jun 24, 2004
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Frankfort, Ky
Aug 9, 2005
#11
  • Aug 9, 2005
  • #11
got an extra lol. I think this one will work for now. Anybody know what a stock rad cap lbs is?

Also I installed the victor water pump at the same time, do you think its putting so much return pressure that its hitting the over flow and comeing out?
 
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grego37

New Member
May 12, 2004
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Fresno CA
Aug 9, 2005
#12
  • Aug 9, 2005
  • #12
stock is 13lbs?
but you SHOULD be able to run a 16lbs without any problems.
It will actually raise the boiling point.
 

krash kendall

Active Member
Nov 19, 2004
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Aldergrove, B.C. Canada
Aug 9, 2005
#13
  • Aug 9, 2005
  • #13
I just put a brand new 13lb. cap my rad after having it rebuilt and it doesn't overflow at all even in this 30*C weather. I previously had a 16lb. cap, but it is apparent now that the rad wasn't cooling properly.
 

Max Power

Active Member
Jul 31, 2003
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St Paul
Aug 9, 2005
#14
  • Aug 9, 2005
  • #14
Don't the recirculating types use a different style cap?
 

krash kendall

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Nov 19, 2004
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Aug 9, 2005
#15
  • Aug 9, 2005
  • #15
The cap has to seal on the sides as well as the bottom. It will work for both systems so long as there is an overflow spout on the neck. I don't know if you can even get a cap that doesn't seal on the sides these days. To make a rad recover the coolant from a catch can you just have to push the overflow hose to the bottom of the can then you rarely have to top up.
 
6

66HertzClone

New Member
Aug 24, 2004
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Central New Jersey
Aug 9, 2005
#16
  • Aug 9, 2005
  • #16
Here are two more things to try. Sounds to me like you have air trapped in the top of the engine. Relying on the upper rad hose to let this out completely rarely works. Remove your thermostat and drill a small (1/8) hole thru the mounting flange, in an area where it would be exposed to coolant. Install the thermostat making sure this hole is at the 12:00 o'clock position, straight up. When you add coolant this hole will let most if not all the air out of the top of the engine. I also recommend that you loosen the temp sensor as you add coolant. Loosen it up a couple of turns, as the system is filling air will escape around the threads. When you start to see coolant, tighten the sensor back properly.

These two things stopped the problem you describe for me on my car, good luck, Jeff
 
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steel1212

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Aug 9, 2005
#17
  • Aug 9, 2005
  • #17
Thanks
 
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steel1212

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Aug 9, 2005
#18
  • Aug 9, 2005
  • #18
Ok, had air in the system and thats why it would send a lot of coolant out the overflow BUT its still getting to hot and the cap is blowing. I'm pretty sure with the high compression heads and the more hp they are making I'm going to need a new rad. It does fine as long as your movine around 180-190 but once sitting still it starts to climb.
 
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grego37

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May 12, 2004
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Fresno CA
Aug 10, 2005
#19
  • Aug 10, 2005
  • #19
You mentioned when you're moving, the temp is ok, but at stand still it heats up.


What fan are you using?
do you have a fan shroud?
where does the fan sit within the shroud?
Did you re-adjust your carb after the head change, maybe running too lean.
 
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steel1212

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Jun 24, 2004
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Frankfort, Ky
Aug 10, 2005
#20
  • Aug 10, 2005
  • #20
I'm useing a flex a lite fan 1300 series 16" fan. I don't have a shroud. I was wondering about getting a pusher fan and putting it on the front of the rad and useing it with a toggle switch? That way I could toggle it on when getting hot and when cooling off at the drag strip. Do you think the addition of that would be enough or do I need an aluminum rad? I can afford one or the other but I would rather not drop 500 on the rad right now.
 
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