62 with 5.7 runnihg hot

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kbill45

kbill45

Joined
Jul 27, 2005
Threads
286
Messages
1,214
Location
Sedro Woolley, Wa.
Did a 5.7 - 700R4 conversion in my 89 to pull trailer carring the 75 FJ40. Had the radiator reworked at the only shop in town but it still runs at 190 with the ac off.. It jumps up to 230 with the ac on. The radiator and block were drained and a flush was used - new coolant added but it still runs too hot. One shop suggested that the radiator was too small and ask what size(cubic inchs) it was. Ido havea transmission cooler in front but the double electric fan seems to pull plenty of air through.

What is the size? cubic inches?

Feed back please.
 
One of the cheif causes of engines running hot is over-advanced ignition timing. You would do better with a mechanical fan; the engine will pull more air than the electric fans ever dreamed of. You might consider using the fans as pusher fans in conjunction with a mechanical. There are some higher-capacity radiators out there, aluminum ones. What thermostat are you running? Is the radiator cap the highest point in the cooling system (other than the funky heater inlet)? Large air pockets that can form in the outlet hose if it is higher than the cap (for example) can make the temps go way up.
 
I'm in AZ as well and everyone I know that ran electric fans here in a 60 over heated and switched. Mechanical fans pull so much more air thru the entire engine bay. I run the stock rad 5.7 4l60e A/c and it will run at 190-205 even in 117. Got the same answer from the radiator shops down here. I did add a small 10" pusher to the front that engages with the a/c as it makes the a/c extra cold.
If your dead set on electric fans you could go with the Ron Davis Man-a-fre sells and it might help. When I was talking with Ron Davis though they told me even with that rad not to run electric fans here as well. You could try a one of the less expense aluminum radiators as well. Really what it comes down to is the stock rad cools just fine just not with electric fans. My friend with a big block actually got a BB radiator from a 70s 3500 to fit. You could try something extreme like that.
 
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What fan are yah running?
How is it wire on regards to the AC ?
Mine runs at 10% at iddle at 50% when above 200F and at 100% when the AC is turned on regardless of the engine temp.
I see 230 temps when Im going over passes pulling my lil trailer but it goes right back down as soon as I reach the passes...

I would also do some reading on regards to Alum rads before you switch over to one.
Mine is been repaired 3 times due to electrolysis... and will be going back to a copper/brass rad.
I take it you are using the stock rad.. it should work just fine....

No argument on a mech fan they pull waaaaaay more air...
My electric set up works great but it will suck when it decides to fail in the middle of no where...
So, Im looking at a mechanical fan set up in the near future....

Any body has part numbers for a 5.3 set up ???????
 
I run factory rad(custom shroud) on mine with mech fan pulling a 18' boat with AC with no heating issues. Also have an oil cooler in place from the oil filter mount, didn't do the conversion, but sure that oil cooler is GM factory.
 
Are you sure the thermostat is working correctly? You could pull it and take a run and see if there's any difference. Are you sure there are not air pockets in the system. Pressurize with hose to make sure there is only liquid in the system.
 
Post up some pictures and let us know full details of engine setup...carb / fuel injection , fans, radiator type....

Yes I'm sure the truck is going to run around 190 given present ambient temps....but most likely should run around 210 with A/c.

more details... I switched to mechanical GM fan and fan clutch...FYI
 
Elbert said:
Post up some pictures and let us know full details of engine setup...carb / fuel injection , fans, radiator type....

Yes I'm sure the truck is going to run around 190 given present ambient temps....but most likely should run around 210 with A/c.

more details... I switched to mechanical GM fan and fan clutch...FYI
Click to expand...

I am going back to GM clutch fan. Used georg's engine mount brackets. Now lookijng for a shrowd.

Nothing fancy about the swap. Bought a wrecked 94 2500chevy with 134k. installed a new rear main seal and put it in. Before the install I cleaned up the engine compartment and repainted it. Looks really nice but not sureI remember how to post pictures
 
fan & clutch

here is what I run...its the matching fan and fan clutch from a 99 GM pickup or SUV with 5.7. Plus home brewed shroud. This is the fan clutch with the large single threaded nut...I think the 94 year model trucks ran this or the metal blade fan. Your engine vortec?..
DSC00485.webp
 
Elbert said:
here is what I run...its the matching fan and fan clutch from a 99 GM pickup or SUV with 5.7. Plus home brewed shroud. This is the fan clutch with the large single threaded nut...I think the 94 year model trucks ran this or the metal blade fan. Your engine vortec?..
Click to expand...

I have that setup that goes with a 6.0 that will be annotherproject. It is a screw on and I need a bolt on.
 
that's the magic question... I don't know...my friend made mine. I can tell you that a reproduction fan shroud from a jeep CJ5 with V-8 would be a very close fit. SOme of the guys have made shrouds from fiberglass.

I don't think anyone makes a bolt on shroud because of the unknown depth and fitting issues...I know some people have modified their stock shroud to work.

I don't know about a source for a V-8 fan shroud.
 
FYI flex-a-lite makes a good 6 blade fan clutch fan that would be a good swap for your TBI engine. I used one on my 92 pickup with TBI. I went with new stock GM fan clutch and used teh steel flex a lite 6 blade replacement fan, worked well on my pickup. I would avoid flex fans or other non clutch style fans.

not sure this is the right model fan but check this out..

http://www.flex-a-lite.com/auto/html/clutch-fans.html
 
I made a shroud both ways. fiberglass and steel. In the end the steel worked pretty well. They both took about 4 hours to make. The steel is nice though because I built it like a modern chevy shroud. Two pieces so it makes working on things very easy. What I did was take a square piece of sheet metal and bend it like a cereal box. I but a double bend on each end though so it would have a surface for mounting holes. I then took the radiator measurements cut the hole and built a shroud around it. I may have some pictures.

There is a shop in phoenix that will make them, I'd have to dig the number up but your looking at about 250-350$ at least if you have someone custom make one.
 
Kurtis said:
I made a shroud both ways. fiberglass and steel. In the end the steel worked pretty well. They both took about 4 hours to make. The steel is nice though because I built it like a modern chevy shroud. Two pieces so it makes working on things very easy. What I did was take a square piece of sheet metal and bend it like a cereal box. I but a double bend on each end though so it would have a surface for mounting holes. I then took the radiator measurements cut the hole and built a shroud around it. I may have some pictures.
Click to expand...

If you have pics, please post because i think I'm going to go the steel route too.
 
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