69 BB cooling issue with reverse pump
Burning Brakes
Joined: Jul 2008
Posts: 923
Likes: 37
From: Green Bay Wisconsin
I was always under the impression that running with no thermostat causes the fluid to pass too quicky through the radiator preventing proper heat transfer. Even without a thermostat there is supposed to be a restrictor plate, a thermostat with no guts, sitting in the housing.
And after the first fill it's normal to have some antifreeze spill out, it will release what it doesn't need and then it will be fine (keep the cats/dogs away) they like the sweet taste of antifreeze.
On a very hot day the car will run hotter without a thermostat to slow down the water flow. When water moves too quickly it can't pickup and carry the heat away.
My old big block runs 200 all day, sometimes a little hotter in stop/go traffic.
I like your reverse flow water pump, the LT1s made amazing power with those.
Douglas in Green Bay
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
And if I stand outside at -20 in summer clothes, I won't feel colder when the wind picks up speed?
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
I have the same front runner on my brand new 509 merlin and as a matter of fact i just had it running last night in the chassis along with a dewitts sp035 27" radiator with twin spall fans. I did not have the fans hooked up yet as I was too impatient and wanted to hear the motor run. (get that done tonight) So I put a commercial fan in front of the rad and the temp held at about 185. If you put in a thermostat the stewarts reverse rotation pump requires a thermostat with 3 3/16ths holes drilled in it as the stewarts pump has no internal bypass. Also make sure you are not too advanced and that your carb is not too lean or you will get hot fast. I have a friend with a 65 small block that after a body off an carb rebuild etc the engine started overheating. He had changed so much he wasnt sure what was wrong. Changed head gaskets etc only to find that his carb had been rebuilt wrong and was way too lean.
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
I just thought of another thing. Where is your temp sender? If its in the head it will show higher temps than if you have it in the intake by the water neck. I was told that the temps in the head are about 10% higher registering on a gauge than by the water neck. The temp sensor for my system is in the radiator right under the upper hose connector and is set to call the fans at 195 and go off at 175.
Thread Starter
Instructor
Joined: Jul 2006
Posts: 208
Likes: 0
From: Hamden CT
St. Jude Donor '12
Until winter, changing to something like this might help.
http://www.summitracing.com/parts/DER-17618/
Its still a flex fan, but I bet it pulls a bit more air than the one you are using now.
http://www.summitracing.com/parts/DER-17618/
Its still a flex fan, but I bet it pulls a bit more air than the one you are using now.
Thread Starter
Instructor
Joined: Jul 2006
Posts: 208
Likes: 0
From: Hamden CT
St. Jude Donor '12
Thread Starter
Instructor
Joined: Jul 2006
Posts: 208
Likes: 0
From: Hamden CT
St. Jude Donor '12
I have the same front runner on my brand new 509 merlin and as a matter of fact i just had it running last night in the chassis along with a dewitts sp035 27" radiator with twin spall fans. I did not have the fans hooked up yet as I was too impatient and wanted to hear the motor run. (get that done tonight) So I put a commercial fan in front of the rad and the temp held at about 185. If you put in a thermostat the stewarts reverse rotation pump requires a thermostat with 3 3/16ths holes drilled in it as the stewarts pump has no internal bypass. Also make sure you are not too advanced and that your carb is not too lean or you will get hot fast. I have a friend with a 65 small block that after a body off an carb rebuild etc the engine started overheating. He had changed so much he wasnt sure what was wrong. Changed head gaskets etc only to find that his carb had been rebuilt wrong and was way too lean.
My temp sender is in the intake by the water neck. The timing and carb are right on. It doesn't get hot quick but it gradually keeps creeping up.
Im thinking the only way to solve this is going to be the dual spal setup. Did it fit in with modification? There's not alot of room between the rad and the AC compressor. If you could post a pic or two I would really appreciate it.
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
I dont have the body on the chassis yet but the radiator support is mounted to the front crossmember so it is in the correct position. I can tell you that without the mech fan and the fan shroud their is allot of room now between the radiator and the front runner. The twin fan module from dewitts is very thin. One of the really cool things about the shroud that mounts the fans is that it has rubber damper doors all over it so at speed the dampers open up and allow full flow through of ambient air at speed. Someone put a 73 radiator support in the car with the 27" rad so I had to order the 27" core rad so my rad is really wide and the core is as thick as the side tanks. Ill try to snap you a few pic's tonight. Have you hooked up your compressor lines yet? They wind up very close to the control arm so I may have to have vintage make up a line kit with a 90 degree bend in it by the head to get it up higher?
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Thread Starter
Instructor
Joined: Jul 2006
Posts: 208
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From: Hamden CT
St. Jude Donor '12
I dont have the body on the chassis yet but the radiator support is mounted to the front crossmember so it is in the correct position. I can tell you that without the mech fan and the fan shroud their is allot of room now between the radiator and the front runner. The twin fan module from dewitts is very thin. One of the really cool things about the shroud that mounts the fans is that it has rubber damper doors all over it so at speed the dampers open up and allow full flow through of ambient air at speed. Someone put a 73 radiator support in the car with the 27" rad so I had to order the 27" core rad so my rad is really wide and the core is as thick as the side tanks. Ill try to snap you a few pic's tonight. Have you hooked up your compressor lines yet? They wind up very close to the control arm so I may have to have vintage make up a line kit with a 90 degree bend in it by the head to get it up higher?
How much room did you end up with between the spal fan lip and the compressor? I have not hooked up my compressor lines, not quite ready for that nightmare just yet. Another over the winter project that's on my list.
Drifting
Joined: Jul 2008
Posts: 1,873
Likes: 27
From: Sonora CA
I tried that coolant additive, made absolutely no difference at all!! If you read the entire label, it actually tells you that that it MAY lower the water temp, only 3 to 4 degrees and then only if you have a 50% or less solution of anti-freeze.
Last edited by imariver; Aug 19, 2009 at 08:39 PM. Reason: mis-spell
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
Ok I got my spall wiring harness temporarily hooked up and working last night. These fans kick but. I had the engine idling at 1000rpm in the garage for almost 45mins the ambient temp in the garage was 105 with the engine running (I'm in New Jersey) and we've been having a heat wave. The engine ran for about 5-10 minutes before getting up to 195 when the fans came on. In less than a minute the fans took off 10-20 degrees and shutdown. They then cycled like that on and off about every 3-5 minutes. This is a brand new Iron headed 509 dyno'd at 590hp only 9.5.1 compression for the street. McJacks headers and 2 1/2 allens stainless chambered exhaust front to back so no restrictions at all (the chambered sections are 3 inches wide). Ive got some pictures to show the fan clearance but cant figure out how to put them in here.
