Running a Little Bit Hot Tonight!

From the pic, I counted 43 rows of tubes vertically. That's the standard GM HE configuration so there should be enough total tubes to cool yours.

 

I am pretty sure it isn't blocked but I'll take the t-stat out and check again with a flex retrieval tool to be sure. Both heads seem to be reasonably equal temp wise. I'll drain some before I swap radiators and check the flow. I used no sealant except across the front and back intake seals and a dab in the corners of the composite and rubber meeting at the head/block angle. None at all on any ports on the intake.

It may be a little heavy on the antifreeze. Certainly not 70/30 but higher than 50/50 since it didn't quite hold 4 gallons when I topped it off with water. I'll only put water back in it this time.

Yes, it is a beefy, light item. I'm hoping swapping it for the old one makes it worse/faster to heat up. It does have a lifetime warranty if it doesn't cool the car.

At least it is no longer my daily driver. Back in the day, I would come home from college on a weekend, swap motors and transmissions and drive it back to college. Then again big block Buicks were a dime a dozen in 1980. Now it has been a month since the engine swap and I'm still ironing out problems but I have the luxury of contemplation time.

 

Just my experience- started break in run, ambient temp at 55, 10 min in 210 and climbing, shut down,cooled, added pusher fan in front of car, took about 15 min to 210. Shut it down and noticed clutch fan spun for what seemed like a minute. Replaced with a new HD clutch assembly(Advance Auto had in stock). Took a couple degrees of advance out on start up (should not have made2 changes). Temp went to 200ish, visible opening of thermostat on temp gauge and just fluctuated right around 180. Big difference in observed air coming through radiator. Now while out on the road, a couple of spirited runs and I'm at 210, but with a steady cruise I'm back at 180. 3 row brass for the record, iron heads,SP1, 4 speed, no shroud, looped heater hose.

 

I don't ever recall fixing an overheating situation or running hot situation by changing the concentration of anti freeze or by monkeying with vacuum advance. I don't use vacuum advance on either of my BBB's and both do just fine on the street temperature wise. If the ignition timing is off considerably, enough to cause an overheat situation, then I would expect to hear an accompanying lack of power complaint.

On a race car, a restrictor in place of a thermostat is the norm. On a mixed-use, a thermostat is just fine. Millions of cars on the road today use a stat w/o issue, and it allows the engine to reach operating temperature sooner, less chance of fouling plugs or putting fuel in the oil etc. Buy a brand-name stat, no Chinese junk.

If it turns out that the radiator is the culprit, I'd suggest a Spectra Premium CU-161 from Amazon. It's about $100 to your door and I have that radiator in both my BBB's as well as 2 other BBB's with absolutely no problems whatsoever. Since brass and copper radiators are getting harder to find for our old Buicks, and their construction inferior to what they were 30 years ago, Napa is now listing the CU-161 (NR-2700) for our BBB's. Yes it has plastic tanks and a little fitting is necessary, but time has proven the aluminum/plastic tank design highly reliable, efficient and economical.

 

Well, glad more than me thinks the vac advance and the timing is probably not the culprit.

Tonight I drained a gallon out. It tested 4 balls -25 on my cheap tester. Didn't float all 5 so definitely less than max strength. I filled it back with tap water (for now, since I'll probably drain it again and again while troubleshooting) to a few inches below the neck. Started it, could see water trickling through the top holes, both sides. Revved it up and water squirts out pretty good from all uncovered holes.

Went ahead and topped it off with water, put the cap on and watched the temp gauge. Still didn't see a noticeable change in the temp when it go to the thermostat temp, climbed to 180 pretty quick. At idle as long as I ran it, 5-10 minutes max, it got to just under 200. Shut if off and watched it creep up to 210.

Did not drive it but while it was first started and fast idling (1,000 w/screwdriver) with the choke wide open, if I tried to close the choke with less than 1/2" at the back of the choke blade to carb body, it would start sputtering. Closing it any did not increase the cold idle. Putting my hand over the front barrels started to choke it out and stumble.

I know, not scientific and not going to tell me what the A/F ratio is but I don't think it is lean, especially if choking at cold idle hurt instead of helped.

The head teacher at the local trade school told me to bring it out some time and he'd put it on the chassis dyno. I'm guessing they have a tail pipe sniffer. May give him a call once I get it cool enough to move a few miles without blistering the paint on the hood.

Here's a video. Almost impossible to get footage of the radiator and rev it while holding a light to get any view inside. About all you can see is idle trickle but it is a pretty good flow for those 2 x 1" tubes.

[video=youtube;I6YBWqYkmjU]https://www.youtube.com/watch?v=I6YBWqYkmjU[/video]

 

Just reading through this thread. How hot is the radiator getting?
Check your inlet and outlet temps with a temp gun. Check the core in multi places. This will tell you if the radiator is cooling the water.
Have you observed the flow of water with the cap off?
These are just some of the things I would start checking.

 

When you rev it, the water should shoot out of those tube and hit the inside wall of the tank..

At the speed that thing was running, it should flow twice what you see there. It's barely trickling out the tubes.. is the T stat still in that thing?

That is the flow I would expect with a T stat partially open.

JW

 

I had already swapped the 160 in the other evening. That was at 180 with the 160 thermostat in it.

I will take it out tonight if I get a chance and repeat. The idle was only about 700 in the parts you could see the water. It squirts out pretty good when it revs up but not all the way across the tank.

If thermostat removal doesn't change it, bad water pump? I'll still probably swap radiators too when I get a few extra moments.

 

Knucklebusted,

What is your reasoning for running without vacuum advance?

-BC

 

It was busted when I got it and was a vacuum leak. At the time I thought I was a drag racer and it wasn't needed. For the last 35 years I've just been to lazy or busy to fool with it.

I bought a small body HEI and MSD6AL off a board member that I'm going to transplant once I get this heat thing lined out.

 

Define "small body HEI".

Are you talking about a points distributor that's been converted to a magnetic pickup and has a four-pin HEI module stuck to it somewhere? Or is this a points-distributor that had a magnetic pickup and no HEI module? Or a points distributor with some aftermarket "points eliminator" kit?

 

Not much pitch on that flexfan?

 

Fan also looks a bit small dia for the shroud

 

It is a factory distributor with a hall cell pickup and an 8-tanged reluctor wheel.

It is this one: http://www.v8buick.com/showthread.php?249025-455-dist-and-msd-6al-box&p=2036543#post2036543

I think it is the angle. It has at least as much pitch as a factory clutch fan. If swapping radiators doesn't change anything, I'll put a clutch fan on it.

How much gap should one have? It is pretty well centered, just inside the shroud and I measure about an inch between the fan blades and the edge of the shroud. Any more and I'd suspect they might tangle if things get too sporty. It looks like a much more substantial fan than my 350 fan.

 

Well, any updates? o No:

 

Yes, after the great ball joint crisis of Aug 8, 2015, it is back on the road. I drove it to return the ball joint press and it got to 210 on the dial.

Oddly enough, after draining 1.5 gallons of coolant and adding back in 1.5 gallons of tap water, it didn't go as high. It only hit 210 instead of 220+.

On top of being slightly cooler on an 85F day, it would heat up driving to 200-210 but cool back down to 180-190 while sitting at a stop light. That smacks of something. Poor air flow?

All my heat searching was interrupted by the need to have wheels attached.

I'm going to start on the carb and swap the radiators this week if I have time. It was very hard to start after shutting it off at the parts store. I had to hold the throttle down like it was flooded and it drops a spark every now and then. It will purr along for a moment then it feels like one spark is missed. Not a dead miss, just every few seconds. I did change coils and it may not be up to snuff. It is of unknown quantity and was laying in the parts bin I have in the corner. It didn't act like this with the old coil.

 

The carb was nasty. Got it apart and ordering parts from Cliff tomorrow. Radiator is drained but haven't swapped it yet as I can't drive it any way until the carb is back together.

 

So, an update:

1) Carb rebuilt, roughly adjusted and bolted on
2) New gas tank, without dents, clear coated and will go in tomorrow
3) New fuel sender, verified full at max float and empty at min float, ready to go in
4) New tank strap bolts and captured nut clips
5) Sound deadening mat for making a tank pad and tank strap isolators
6) Several lengths of 1/4", 3/8" and 7/16" gas line and a new tank vent ready to go
7) Electric fuel pump cleaned up, flushed out (had some gunk in it) ready to mount
8) Fresh gas in a new can ready to go
9) Radiator swapped to 4 core brass and no thermostat (That's two cooling changes but I'm running out of patience and want to have it moving by the weekend)
10) Factory 7 blade clutch fan standing by in the wings
11) Intake checked for blockage while thermostat housing off, clear from head to head

I talked to a buddy that has a Hemi Challenger, also marginal cooling. He was a cooling engineer in a former life and offered some suggestions. First he agreed the thermostat probably wasn't the issue but also suggested going full deionized water and water wetter. He says he saw a solid 20F drop in his Hemi over 50/50 water and antifreeze. He thinks the brass radiator is probably sufficient but the aluminum one should have been better. He suggested flow as the problem. Deionized water is a bit expensive so I'll probably just go distilled water.

If this doesn't solve it I'm going to go whole hog with a new T/A front cover and water pump! Something has to make it work. It just isn't wild enough to run this hot.

 

Did you put it in a container of gasoline to see if the float actually floats?

There's been warnings on other sites I participate on, where the new Chinese float would float in water, but sink in gasoline.