Hey guys, so I need some advice. I just got my t bucket back on the road after sitting in storage for 30 years. I pulled the motor out put in a new cam had the heads ported and polished and a new Offenhauser three deuce intake. It has a brand new aluminum radiator with electric fan and a high flow mechanical water pump. Timing is on the money and it runs like a champ but the temperature climbs to over 210° in about 20 minutes whether it’s sitting still or on the road. I just pulled one of the block drain plugs this morning and there was a hard block behind that plug. I busted it open with a small screwdriver and clean fluid ran out. My question is what’s the chances that the rest of the water cooling channels are clogged? And if so, how do I unclog with the engine still in the car.? Your advice is very much appreciated in advance, thank you.
Didn’t you have the heads off in regards to flow? Water pump correct flow? Lower hose collapsing? Electric fan turning the correct direction and blade in correct position for rotation it’s turning?
Yes, heads were off and there were no visible obstructions that I could see. Pump is good, thermostat works, fan works, hoses are not collapsing.
If you bought a new chinese aluminum radiator that came with an electric fan, then the fan is probably way undersized for what you need. I'd put a mechanical fan on it, but without pictures we can only guess. The drain plugs usually get a bunch of crap stuck behind them because it's the lowest place on the block, that doesn't mean the rest of the system is plugged up. 210 is normal operating temperature for new cars, you need to be concerned if it gets over 230 or so. If you have a pressure cap and some antifreeze in it, you'll probably be ok to about 250 degrees before it will boil. Boiling is bad.
Thanks for the advice, the radiator is from Speedway and its the same fan that was on it before the cam swap.
What is the ignition timing at idle and at higher rpm? and does it have vacuum advance? if so, is it full time or ported?
You say it climbs to over 210, how much over? Is the fan running? Does it continue to climb with the fan on? Since you say it does the same going down the road, (continues to climb) it sounds like a capacity problem.
As strange as it may sound, the “high flow water pump” may be your problem. If the coolant doesn’t spend enough time in the radiator, it will not transfer heat to the radiator which would transfer it to the ambient air. Instead, partially cooled coolant would return to the engine without being cooled enough. Cooling issues can be very simple to fix, as in a bad rad cap, they can also be very hard to diagnose. Did you make any other changes?
I doubt it.... My new 327 has been running up to 220 or so, and it's doing ok...but maybe I'm used to that, living in the desert.
Still waiting for pictures. When it boiled over, what did the gauge say? How full was the radiator? Does it have a puke tank? What pressure rating is the cap? Do you have any anti freeze in it?
I replaced a mild cam with an Isky 292 and upgraded to a Pertronix distributor and coil. That’s the only changes other than going from a copper to aluminum radiator.
What is the stat, and have you removed it to check and see if it's opening fully in a pan of hot water? Might be it's a brand new defective stat as a lot of guys are having issues lately with them. Might also consider one of the engine flush chemicals like Blue Devil and let it work well before draining to see what it flushes out.
I always like to start with simple stuff. Check that the fan is blowing, or drawing, air through the rad. If that’s okay, let it cool down, top up system. Start the engine, and make sure the thermostat opens when it should. You should see coolant moving in the rad. If coolant is not moving, thermostat is not opening properly. If it is opening and coolant is moving, something else is going on. If you have access to a pressure tester, test the rad cap. If it’s ok, pressure test the system. If everything seems okay, set the pressure tester and let it sit and cool down, then pump it up and let it cool completely, as in overnight. Pressure may drop off a bit overnight. If it does, pump it back up. If it holds pressure, start the engine and let it come up to temp. Watch and see if the pressure drops off while the engine is coming up to temp. I know that this sounds like a lot, but it is a procedure. If everything checks out okay, then the next step is to let it cool off again, remove the thermostat, fill everything back up and check for bubbles in the coolant. Check when cold and continue watching until engine is up to temp. Bubbles coming up as the engine is running indicates a combustion gas leak into the cooling system. I have seen bubbles come up when the engine is cold, when the engine is hot, or - the sneaky one - as the engine is coming up to temperature, then stopping as it nears full operating temperature. Bubbles may indicate a bad head gasket, cracked head or block. Again, it sounds like a lot, and can be a long process.
First thing,, needs more initial timing , 16-18 degs,,,,maybe more ,,, then you will more likely have to change total ,,,, Why So many use factory specs on modified engine.... A vacuum gauge will tell you what engine Likes Remove out side carbs until you work things out like idle & cruise AFR!!!, Coolant Moving to Fast or to Slow,,, & Most electric fan 2,200 cfm barely enough on there own Pics would help
Thermostat tested good in boiling water. It was not a problem with the old radiator, it always ran 180-190 at the most even sitting still in the summer as long as the electric fan was on. The new aluminum radiator (from speedway, https://www.speedwaymotors.com/1917-1923-T-Bucket-Aluminum-Radiator,1829.html) has a hidden 15lb popoff valve that has not opened yet which leads me to believe it isn't building up pressure. I have the intake off and am debating whether or not I need to remove the heads, no water in oil or intake valley so I don't want to if not necessary.
I'd pressurize. the cooling system with air at the radiator. It may be as simple as a small leak. The lower the pressure the lower the boiling point.
I ALWAYS post the same answer but..............most of the time it NEEDS checking...... Shivel-ley distrib. are EZ to work on (sorta except they are a booger to ge to !) Put some light weight advance springs on it and with a timing light twist that distrib. until it reads 36-38 degrees TOTAL ADVANCE at 2000RPM or so. Let the initial fall where it may !!! Total advance all in by 2000RPM.........re-adjust the carb and lower the curb idle. Your big cam will love ya. Chance are the temp will come down (some). Not enough timing will let un-used fuel pass through and burn in the headers. Over heating will happen. BTW...220 ain't really that hot with the right radiator cap. Just try it.................. 6sally6
Remember that Chevrolet had two pumps that looked alike but were meant to turn in opposite directions. Make sure that you have the correct one. Pete
I saw back in your other post from May. You had said when you turned the fan on it jumped another 20 degrees. You mentioned the fan is working, did you ever verify the air flow like Johnny mentioned. A number of those after market fans come in a push/pull configuration and either have you reverse polarity or flip the fan blade. I usually use Hadens and I don't recall them having a connector so they have to be wired in. If it was out, is there a chance you might have the wires reversed? I'd also look at the fin density between your new radiator and the old, more density could be restricting your air flow and could require more cfm fan. Also noticed the part number for the pressure valve thats sold separately from the radiator mentions for non pressurized caps, Don't know how much of a difference that makes it your running a pressured cap. Valves also one way, might make sure that's in there right.
Thanks for all of the helpful advice, going to button her back up and set total timing to 36-38 degrees without thermostat and see what happens.
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