over heat idle summer 69 427 installed in 56 chev 2 dr,edlebrock alum heads alum. cross flow rad. 2 12 inch puller fans on temp contrl

Dick
4 months ago

I want to install a bigger rad. a tru 3400 cfm single 2 speed fan but am told by a reputable performance shop I could put to big of a rad. for cooling. I'm on my 3ard set up. What do you think?

Mickey
4 months ago

Sounds like a timing issue. Too little timing will create a hot idle. Could go to a 5.5 inch water pump pulley to pick up the speed at idle.

Mike S.
4 months ago

What do you call overheat? My big block will idle at 210 on a hot day. That's not a problem. Are you sure your temp gauge is accurate. check it with an infrared gun to be sure.

dick
4 months ago

Being honest I rely on my urgent care providers,(mecha­nics)and 3 different ones have said my timing is correct. I have been enlightened by one mechanic about a formula to determine water pump effiency at idle, my march serpatine belt assembly has the correct ratio to provide more water at idle. New guages infrared checked spot on. 200 + or – is what i don't like, i still haven't installed my condenser for air conditioning. I'm told by some i need 24 quarts for cooling capacity and i believe all the air i can get can't hurt. Suggestions or experience appreciated. Thank you all!

Mickey
4 months ago

Correct timing at idle is a matter of distributor curve. I would advance timing in 2 degree increments and see if there is an improvement. If there is, the total timing stop in the distributor can be adjusted to keep the timing at higher RPM to the correct 36–38 total. You need to seek out a high performance mechanic. I'm in the Chicago area. I do this all the time on performance cars.

dick
4 months ago

hey mick wish you were here. thanks will try

Dick
3 months ago

now looking for front schroud from radiator support down to top grill support. 1956 chev.Want to force all air thru radiator. Location to purchase would be perfect. Thanka Dick

Mr Bowtie
3 months ago

Dick,

Mickey is correct on timing and water pump pulley sizes.

Couple more suggestions. My apology for taking so long for answers.

Be cool radiators, which CARS INC carries, specifically makes a aluminum radiator for a 1956 Chevy with a 555 big block Chevy motor, bolt in radiator, for a Customer's car. Runs 180 all day in bumper to bumper traffic on the Woodward Dream cruise in Detroit, through 19 cities with zero cooling problems. All steel, heavy car. Feel free to call us or Fred at Be Cool if you need assistance.

CARS INC carries a fan shroud for 1955–7 Chevrolet's. It is part number 7610 is $99.00 and in stock.

Be Cool can make you a Custom shroud if you wish.

Another commonly overlooked cooling problem, related to ignition timing is ground straps. So many forget to put them back on, especially after a engine removal. Grounds complete the circuit, specifically the ignition wiring circuit. If Ignition circuit wiring ground isn't complete your timing could be off.

1956 Chevrolet had many engine compartment ground straps for this reason. Ground from frame to engine, another from body to engine, and one more.

CARS INC carries the 1955–7 ground strap kit, part number 6652, $17.95 a set, three copper grounds.

Another simple overlook is radiator cap pressure rating. With your big block use a 19 psi radiator cap or higher, 21psi. The old, original 1956 Chevrolet radiator cap is a 7 psi cap, not good for your big block.

Hope these suggestions help.

Dick
3 months ago

thank you very very much! will make contac with cars inc. AGAIN thank you very much!

Dick
2 months ago

reinstalled freshly finished hood hinges with same springs cant get hood to reinstall per before. Any one got a suggestion by the step to correct my reinstll of hood

*
Comment *
Your Name *

Post a New Topic

Ask Mr. Bowtie Forum
CARS Inc. is happy to provide as a free public service a Question and Answer forum for Classic Chevy lovers to ask questions, and then discuss with each other topics relating to all things having to do with restoring classic Chevrolets.

The forum is set up to allow any car lover an opportunity to have a dialogue with your fellow car lovers. The more that Classic Chevy owners interact with each other, the better.