Overheating Problems

[greenmod]

I'm currently running a double pass radiator, 5/8 restrictor, stock water pump, fan shroud, and a 6 blade 18"fan. 602 crate engine! Car is running 220 to 230 on long runs! Any suggestions?

[JustAddDirt]

fuel mixture good?
check to make sure you do not have any soft spots in the lower hose that may suck shut. (does it have the wire in hose)
I would suggest the 19" GM fan. should never overheat with that.
how old is the radiator?

[greenmod]

Fuel mixture was just done by stealth, but I'll double check and see! Hoses are brand new and it looks to me that somebody has made a single pass into a double pass! So I'm thinking about changing the radiator and fan!

[stock car driver]

If your fp doesn't have enough gph it doesn't matter where they have the carb you bought jetted. The whole system needs to be correct.

I use a chassis dyno to tune my stuff.

[JustAddDirt]

I agree with SCD
unless Stealth ran your motor on a chassis dyno or some sort of tuning, on your motor, it will be almost impossible to build carb, and bolt on a motor, and it be 100% correct.

I would put a single pass radiator in it, and a 19" GM fan.
GM part number 405442
AC Delco #15-80752

same fan, AC Delco is considerably cheaper.

[Matt49]

I would also suggest a single pass. Double pass just makes the pump work harder.

And I agree on the 19" GM fan. Bolt it on and the first time you start the car you will feel the difference if you are standing at the carb.
For two pieces of stamped metal riveted together, GM sure is proud of it, but that fan moves some serious air.

[bob75]

Do you have anything in front of the radiator on the lower half, I did and it ran that temp. Took it off now I'm running 160-170

[twisterf5]

we run 602 i run 15% pulleys run the stock stat and a 18inch single blade with a single pass rad we run 190/205 on race gas. something like chp we run 650 holly ultra hp but we do dyno test that is a must and we have no air holes in the front. that what works for us.

[powerslide]

Stock water pump has got to go. Find a stage 2 or better Stewart see used ones on eBay on occasion then take the restrictor out.

[greenmod]

Thanks for all the help! Going to change to a single pass with the gm fan and try that!

[JustAddDirt]

if you look for the AC Delco part number you can typically find them on Amazon. right around the $80. depending on were you are at, you can get them in 2 days or so.
might also get ahold of Brad Hibberd (SP) on here with race1. I think they sell a 2 blade fan that is made like the 4 blade GM unit. they say it moves more air, at 1/2 the HP loss.

[stock car driver]

18" is 32 pitch

gm is 36

on a chassis dyno there isn't much if any measurable hp difference

[greenmod]

Switched to a single pass radiator, new aluminum water pump, and no restrictor! The whole nose is boxed in on the radiator with a shroud! Fuel mixture was ok! Still running 220 to 225 on long runs! Don't know where to go now!

[stock car driver]

I run a racing stat. timing, jet and fuel pressure effect cooling a lot.

still on the 6 blade fan? cut 3 off it will pull more air.

post pics of your shroud

drain the block and radiator. fill it with distilled water, run it for a few minutes, drain it all again then fill it again and run it.



I wouldn't box the front in front of the nose on a mod, Id leave it open to draw air from every place.

[powerslide]

I agree lets see pics of the shroud, and do you still have 6 blade? If its one of those flex fans its not moving any air. On the 405442 fans you can put a piece of paper or cardboard in front of the radiator and it will suck it up against the radiator because its pulling so hard.

What brand of pulleys and are the belts rubber band tight? 1-1 or reduction pulleys? I think you need 1-1 because the low RPM you run a 602 at.

[stock car driver]

If you cant turn your motor with your fan your belts and or pulleys are too loose and worn and are slipping at rpm..

you MUST be able to at least turn the motor enough to remove the timing chain slop then back the other way or they are slipping

v belt alum pulleys are good for about a season usually

[25drtrkr]

Be sure your fan is centered behind the radiator. We had that issue on a Dirt Works before. Also, you got to have that 4 blade gm fan, cant stress that enough. Your 220-225 temps isn't going to hurt anything with those steel Vortec heads, but you don't want no more temp than that.

[HuckleberryB4]

Without reading all posts, with a double pass you NEED a stage 2 or 3 high volume water pump. The radiator cap should also be rated around 29-32 lbs. Also, completely drain the coolant system. Run all distilled water and a bottle of water wetter. No coolant. The water wetter has enough lubricity properties to protect the system.

[wallbangerII]

tell me more about single blade fans please. are they one blade of a gm fan ? do they crack and break ?

thanks

[stock car driver]

whatever 4 blade you cut two off

[hughesracing9]

^^^ this! i bought one and that is literally all it is...plus a decal on the edge of the blades

[stock car driver]

^^^ this! i bought one and that is literally all it is...plus a decal on the edge of the blades

I beat my head against a wall trying to tell everyone they can cut two off on their own for years. (I started running single blade in 2008 for sure all of 2009).

I finally caved this spring and started buying all star fans and cutting them off and selling them for $60 shipped. It is amazing how many guys do not want to cut their own.

[HuckleberryB4]

How do you benefit from a 2 blade more than a 4? Less Turbulence? Run it with or without a shroud? I have an extra 19" Allstar 4 blade I'm thinking about cutting up now. lol.

[HuckleberryB4]

Found this while researching.

http://store.crateinsider.com/2-blade-18-steel-fan-by-hendren-racing-engines-multiple-colors/

We run around 210* - 215* with a double pass, the GM 19" fan on gas and no shroud in a LM. Wondering if I would benefit from going to this with out the shroud still.

[billetbirdcage]

How do you benefit from a 2 blade more than a 4? Less Turbulence? Run it with or without a shroud? I have an extra 19" Allstar 4 blade I'm thinking about cutting up now. lol.

It's pretty simple really, while a 2 blade or other type fans that don't/won't pull as much air but reduces the power used to turn it. It basically boils down to how much airflow you need for your set up to stay cool. If you have more then enough airflow, then going to a 2 blade or smaller 4 blade fan will free up some power, thus may or may not increase temps depending if you still have the airflow you need.

It's not rocket science. But as a general statement if you running a crate that you are close to wide open all the time, then you may run close to the edge with a 2 blade on gas. E85 makes it a little more tolerable. Obviously it depends on engine load, outside temps and the rest of your cooling system and how efficient it is whether you can run one with no issues or not. (this is more based on a crate LM, I could see a mod getting away with the 2 blade way easier due to smaller tires and probably less load on the engine for a given lap).

[25drtrkr]

Found this while researching.

http://store.crateinsider.com/2-blade-18-steel-fan-by-hendren-racing-engines-multiple-colors/

We run around 210* - 215* with a double pass, the GM 19" fan on gas and no shroud in a LM. Wondering if I would benefit from going to this with out the shroud still.

Those come from Hendren and they are balanced also.

[stock car driver]

It's pretty simple really, while a 2 blade or other type fans that don't/won't pull as much air but reduces the power used to turn it. It basically boils down to how much airflow you need for your set up to stay cool. If you have more then enough airflow, then going to a 2 blade or smaller 4 blade fan will free up some power, thus may or may not increase temps depending if you still have the airflow you need.

It's not rocket science. But as a general statement if you running a crate that you are close to wide open all the time, then you may run close to the edge with a 2 blade on gas. E85 makes it a little more tolerable. Obviously it depends on engine load, outside temps and the rest of your cooling system and how efficient it is whether you can run one with no issues or not. (this is more based on a crate LM, I could see a mod getting away with the 2 blade way easier due to smaller tires and probably less load on the engine for a given lap).

Wrong, I guess it is rocket science...

A 2 blade pulls MORE air than a 4 blade.. think about it a little.

[stock car driver]

Those come from Hendren and they are balanced also.

Balanced? That's a new one..

They are all star fans with 2 cut off.

Even the gm fan which is advertised as balanced is NOT balanced, if you order 10 of them they all have the same weight in the same place riveted on....

[billetbirdcage]

Wrong, I guess it is rocket science...

A 2 blade pulls MORE air than a 4 blade.. think about it a little.


OK, but my test shows different

17% less air flow, now granted my air flow meter didn't go high enough that I could get to full RPM on the fan.

[stock car driver]

OK, but my test shows different

17% less air flow, now granted my air flow meter didn't go high enough that I could get to full RPM on the fan.

B.S your full of it.

[brad hibbard]

all of our 2 blade fans are balanced by us------we check and adjust our 4 blade fans when we put them with an engine package

we remove material from the heavy side rather than adding with a rivet and washer

Brad
www.race-1.com

[25drtrkr]

Balanced? That's a new one..

They are all star fans with 2 cut off.

Even the gm fan which is advertised as balanced is NOT balanced, if you order 10 of them they all have the same weight in the same place riveted on....

Steve posted that in an article awhile back. If they're not, you can take it up with him.

[stock car driver]

I dont care either way.

[hughesracing9]

Its less about pulling MORE air with a two blade compared to a 4 blade, but pulling close if not equal amounts of air with less drag using less blades. But me personally thinks 2 blades pull more. Only "X" amount of air can be pulled by the fan. If you take 2 blades away, thats less air being occupied by the extra blades to allow more air to be available. Im sure there is some science literature with it, but Ive run my car with a gm 4 blade and a 2 blade I got from Race 1. I have trouble getting over 200 ECT using the same motor and cooling system as last year using the 2 blade with a increase, although slight, on a dyno.
I love the 2 blades, but i do feel it is a simple conversion for anyone to do with a GM 4 blader, but thats just me. I already have a 2 blade, that i guess is balanced, and dont think i will need to buy a new one for a while