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Author Topic:   Running hot?
posted August 12, 2003 11:50 PM
I am looking for any way to help keep my temp down... I will try to help with what i have and what i have tried. I have a 16"x22" rad that sits low in the car and the fan is above the top about 2 1/2" there is also a peice of tin at the bottom in front to keep the mud out wich only leaves 12" of rad exposed to incoming air. I have the kse pulleys the cog type with a plastic fan about 15" dia...about 1 1/2 from rad. I have tried about 3 dif types of fans. I have a allum water pump that i have chnged 2 times. I have tried 160,180 t stat and a 5/8 restrictor. I have chnged jets up and down 6 to 9 jets sizes. I also ran water from the back of the intake to the front of the intake. I also have tried timing up and down. Now what else will make a motor heat up...i really think its somthing that i have done i have had 10 diff motors with 3 dif dist and 3 dif water pumps and 5 dif carbs 3 dif cams from 3 dif manufactures... I have about 3 feet of exhaust pipe on each side 3 1/2" with the straight threw mufflers and turn downs...also run super traps with from 9 to 25 disks in them. I also have put tin on both sides of the nose to help direct the air. I see guys all the time running 140 or 160 till they race then only get up to 180 or 190....i can get to 180 in less than 10 min and it keeps going and never seems to cool down? What am i missing here....I have looked at tring to put a shroud but i am not sure how to go about it to make it work right and not be made of cardboard and duct tape....i would use it if it worked. Sorry this is so long but it has really been bothering me for the last 4 years....I mean im the guy that i start drive to the line up ...shut it off till its time to go on the track....i mean i dont start till they wave us on...then hope for not to many yellows. I hope that you guys can give me some ideas or maybe a way to build a shroud with what i have in my shop? Thanks, Craig Moore

jhon hollomon
posted August 13, 2003 12:08 AM
Have you checked your gauge and temp. sending unit?? They might not be reading correctly. Where is your temp sending unit located?? How hot does it get in a feature?? Are you on gas or alcohol?? Also, is your radiator a single or double core?? Are all the cooling fins straight and not bent in restricting airflow?? Just some other things to check.

[This message has been edited by jhon hollomon (edited August 13, 2003).]

posted August 13, 2003 02:06 AM
what size is your water pump pulley compaired to your crank pulley?

what do you set your timing at?

posted August 13, 2003 07:42 AM
Have you tried to run no restrictor in the thermostat? I know we never had one and everyone told us to put one in and we started over heating so it is back to wide open. The thing that I don't like you said the tin blocks incoming air. You need to get that opened up. Get as much air coming in the grill to go through the rad. And I would try some water treatment. A cap full of fabric softner would do wonders. The trick I have seen used in the past. Hold a lit cigaret in front of the grill with the motor running does the fan pull the smoke in? If not then move the fan closer to the rad or build a shroud. We dont have a schroud either but our box in front of rad works well.

Jason Boivin

[This message has been edited by jay116 (edited August 13, 2003).]

posted August 13, 2003 08:07 AM
Are you still running the block that is half full of HardBlock? That'll cut down the ability for the engine to stay cool considerably.
Also, as I've stressed before, a 1:1 pulley setup, NO restrictor, HV water pump and just (maybe) Water Wetter in the system usually helps cure overheating.
Stewart Pumps' website has all the tech info needed on the subject.
Your fan could be less than efficient, but as long as it's placed correctly in relation to the well-built shroud and (as it looks like) your ductwork to the radiator is good, then there should be no problems there.
I'd first try the no restrictor and HV water pump with 1:1 pulleys and if that doesn't help, then my guess would be most of the source of your problems is the limited coolant flow due to your block being half full of cement.

Hope that helps,

[This message has been edited by KPLugnut (edited August 13, 2003).]

posted August 13, 2003 01:32 PM
No this block has nothing in the bottom....The ones i have had filled i didnt have that much problem with.I would guess the pulleys are 50% the top being twice as big as the bottom. I am going to raise the rad so more of it is exposed to the incoming air and to put the fan more in the center....taking the restictor out will be ok? I would think it would pass to quick...the water pumps i have are the speedway allum type. This is a allky motor with 154 jets at sea level and plugs seem to be fine. Would exhaust help or hurt in this matter....and any idea for a shoud ....or do i just need to spend some time with some allum and try and make it work.... BTW i have blown a few motors with this rad but the fins are all straight...i even checked em arter it was hot thinking they were swelling only under presure.... Help i would like to try somthing befor the weekend?? thanks guys..

jhon hollomon
posted August 13, 2003 09:39 PM
You might have it flushed and checked for flow. You could have some junk in the cores.

posted August 13, 2003 10:59 PM
Well i just got in from running it. Last night i did a clean on the rad with some really good stuff by prestone...made the inside like new and the water flows out very fast now when befor it kinda chuged out. The temp seem to stay down and i ran it about 20 min total and was just under 180. I just got done putting mufflers on the car would that make a diff? The car seems to idle better now also. The mufflers i had were the straight threw ones with the luvers on the side and about 3 feet of pipe total, now i have the spiral inserts with 2 1/2 feet of you think it has a factor in it?

posted August 14, 2003 09:21 PM
we are having a bad overheat problem we can't find out why either...not to sound dumb, but what is the "old cigarette trick"??

posted August 14, 2003 09:54 PM
hold a lit smoke in front of the car with it running, the farther out you can get and still have it pull the smoke in, the better. This will give you an idea if you are getting enough airflow through the rad. We had an overheating prob. early this year and tried putting 2 caps full of the wifes fabric sofener in it. Dropped 20 degrees and smeels great.

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