cooling system

[aussie merc]

check out previous posts and only wound up confused so here we go 1 what is the flow rate from a standard waterpump 2 flow rate from bob drake hi flow waterpump 3 factory thermostat setting and valve dia the drama is evey time i take it over 2000/2500 rpm it starts to overheat 190 deg + and climbing back off and it returns to normal dosent matter if its a 2nd gear pull or just flat cruising 1 current radiator is brass and copper repo of factory split 4 core has been tested and given clean bill of health 2 current thermostats are 175 deg hiflow valve dia 11/2" 3 current waterpumps bob drakes hi flows [originals started to weep oil into coolant] 4 coolant has been tested and no signs of combustion [headgaskets] leaks 5 fitted with twin 97s twin exhaust with fenton headers running 3.54 rear gears on 600 16s 6 cooling system has been flushed ,flushed and reflushed cleaning out god knows how much mud 7 have fitted air dam to top front of radiator and refitted bottom factory under tray so all air entering the grill must go thru the radiator 8 normal suburban driving and stop start all fine stays at 175 with electric fan cutting in at 185 and out at 180 as required Problem only exists on open road what am i missing or is this just life with a flathead

[Tinker]

Spaced these questions out a little.


check out previous posts and only wound up confused, so here we go.


1) what is the flow rate from a standard waterpump

1A) flow rate from bob drake hi flow waterpump?

2) factory thermostat setting and valve dia the drama is every time i take it over 2000/2500 rpm it starts to overheat 190 deg + and climbing back off and it returns to normal. Dosent matter if its a 2nd gear pull or just flat cruising.

*1 current radiator is brass and copper repo of factory split 4 core has been tested and given clean bill of health.

* 2 current thermostats are 175 deg hiflow valve dia 11/2"


3) current waterpumps bob drakes hi flows [originals started to weep oil into coolant].


4) coolant has been tested and no signs of combustion [headgaskets] leaks.


5) fitted with twin 97s twin exhaust with fenton headers. Running 3.54 rear gears on 600 16s


6) cooling system has been flushed ,flushed and reflushed cleaning out god knows how much mud


7) have fitted air dam to top front of radiator and refitted bottom factory under tray so all air entering the grill must go thru the radiator

8) normal suburban driving and stop start all fine. Stays at 175 with electric fan cutting in at 185 and out at 180 as required.


Problem only exists on open road.

What am i missing or is this just life with a flathead?

[uncle max]

Bump the timing a degree or two.

[aussie merc]

first of all thanks to tinker for seperating the questions [tried but failed again] and to uncle max i expect that by bump you mean advance currently runnining 4 deg btc also running on 91 octane [ethanol free]

[Lawrie]

I,m sure it is not usual with a flathead .Our 33 with a 99a engine,Drake pumps,normal t/stats welded to a short length of stainless tube and slipped into the top hoses,stock 33 radiator,that has the tank taken off and all the tubes cleaned,block cleaned when building the engine,single 97 carb, cast iron heads
Will tow the caravan all day, last avalon air show towed in the hills from Nimbin on the way down to Griffith at 44C, lots in 2nd gear,NO overheat other than the pasengers.at griffith ran around town for 3 days 47 C ,cool as .
the other month or so back, out to Ayers rock ,no drama.
Lawrie

[aussie merc]

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exactly my delema what am i missing dosent make sense as ive seen blown flatheads with stock cooling systems that dont overheat and a blower will stress a cooling system like nothing else

[37 Cab]

Initial timing may be 4 degrees but your total timing needs to be looked at. How much advance are you getting? Also could be lean mixture. My 37 will run 3000 rpm all day with no heating concerns. Also you might remove thermostats to eliminate those as a concern.

[Lawrie]

I dont want to scare you BUT,the 33 had a slight o/heating problem a few years back.woul;d loose water on a trip ,sometime 6 litres at the servo on fill up sometimes 2 .
turned out to be a cracked cast iron head,
BUT you must take off the tanks on the rad and clean out the tubes,that was the main thing that got the 33 to run cool,
I use 91 fuel
Lawrie

[Talkwrench]

AS Lawrie said the tanks need to come off and be rodded out .. But be prepared if its an original as they start springing leaks, expensive fix but you have a new radiator . Also dont forget how much crap can build up inside the block .. And timing is another thing.

[flatjack9]

What distributor do you have?

[aussie merc]

dizzy is mallory unilite was already on vehicle when purchased but back to my 1st 3 questions what was the factory thermostat temp setting what size was the valve and how much did the factory pump actually pump as of yet no answers and read the post the radiator has already been looked at

[Kurt in NJ]

I had 2 radiators "checked over", told good flow, but when the tank was removed more than 25% of the tubes were clogged,

[Flathead Fever]

My vote is for a plugged radiator too. I'm not sure how someone would check the flow and declare it good. Even if it appeared to flow good running a hose through it, that just means enough tubes are open to handle the flow but that does not mean enough tubes are open to transfer the all that heat to the cooling fins. Usually if an engine cools okay at lower speeds but overheats under a load or higher rpms the radiator cannot get rid of the heat fast enough. You could start off with a clean radiator and have the junk in the block plug it up pretty quick.

Feel the tubes with your hands or measure the temp with an infrared thermometer and see if the feels like coolant is circulating through them. Feel what the tube temperatures are like from top to bottom or side to side on your daily driver so you can get an idea of what a good radiator should feels like.

I went to look for a video on radiator checking with an infrared thermometer and found this radiator thermal imaging camera video. One of these tools would be even better.


https://www.youtube.com/watch?v=KqOodFvHYDM


Infrared thermometer test. I would have performed this test with the radiator still installed in the vehicle so there is constant supply of heat flowing through the radiator. But this will give you an idea of what your looking for. A lot of times you can feel these cold spots with your bare hand and you don't need an infrared thermometer. Its a neat tool to own.

https://www.youtube.com/watch?v=rKkYqnFULy8

[leon bee]

Originally Posted by aussie merc

dizzy is mallory unilite was already on vehicle when purchased but back to my 1st 3 questions what was the factory thermostat temp setting what size was the valve and how much did the factory pump actually pump as of yet no answers and read the post the radiator has already been looked at

Not that I would have any great helpful info, but your posts are very hard to read. I've wondered if this is a stylistic issue, posting with an awkward electronic device, or what?

[aussie merc]

well we aussies speak and spell English not your american dialect BUT I STILL CANT BELIEVE that 3 simple questions are beyond the great collective mind and wealth of knowledge that is this forum

[Talkwrench]

Pretty sure we speak English maaate..?
Cant help on flow rates etc , GM or Skip would be the only ones that might know. Cant see anything wrong with what you've done. I have similar my temp will go up when pushing it on the freeway on a hot day wouldn't boil tho'.. The only thing I put it down to is that I dont have vacuum advance, maybe its in your timing and the block can still hold heaps of crud. My thermostats are just commodore 180 ones. Perhaps try without? I can understand it being frustrating..

[aussie merc]

luck would have it went to swapmeet found a set of NOS thermostats that actualy work as a pair temp setting 180 deg valve size 1 inch so that answers 2 of my questions will fit and test keep you posted thanks to all for their inputs

[Kurt in NJ]

What engine do you have in the car ???---not mentioned in any posts other than carb, dist, is it 60hp---- is it stock, have stock cam? has advance rate been checked on dist,

I had a non stock muffler cause overheating on that bank on hard pulls, high speed

without knowing what engine can only guess on stock pump output
60hp ---20 gal min at 3000 engine rpm --each pump
37-48 pump for 85-100 hp ---45 gal min @3000 rpm --each pump

drain the coolant down some so top tank is empty, look in and look at tops of tubes, any that still have coolant are blocked, any covered over are blocked, the radiator core will flow more than water necks will flow, a radiator flow test won't be able to prove all tubes are clear, also the fins need to be bonded to the tubes so heat can transfer, I have seen the tubes fit to fin loose

The thermostats I had in the 46 were NOS, came from ford boxes, not made like modern thermostats, opening much larger than 1", it was a flapper door much like a throttle in carb, open was like full throttle, almost the diameter of the head outlet --they were 160 degree
the 60hp thermostats have larger than 1" opening

[aussie merc]

Update just had it out for a 6 hour run all GOOD sat at 180 slight rise in traffic to thermos cut in and back to 180 no problems looks like the 1 inch valve did the trick those high volume pumps must really move some water

[Talkwrench]

Great ..So it was a smaller opening?