Hello all. My name is Jonathan and while I've been a long-time reader, I'm a first-time poster. I recently picked up '49 land speed Ford Pickup (seems I found Bubba Ignition's old truck) and am trying to get it back on the road. The truck was overheating and exhaust gas was in the coolant (chemical test and spouting on startup) so I took the heads off and had them decked. While off I checked the block for cracks using Cantesco's penetrant kit. No cracks were found. Put them back on and am seeing the same issue. I think I have a cracked block somewhere not on the mating surface, but I am hoping there is some other issue and figured I'd ask to see what you all think. Am I just running on hopium and need to start shopping for a used replacement block? Thank you all. Regardless, I'm glad to be here. Please let me know if I posted this in the wrong place or made any forum fopaux.
I did. The heads checked out. But am going to call the shop again this morning to confirm they did. The truck overheats pretty quick. Faster when the motor is above idle. @squirrel Thank you for the welcome brother.
What method was used for checking the heads ? Both an overall "HOT" water pressure test, and either a dye penetrant or a magnetic test, in each combustion chamber. Same for the block, was "HOT" water used ? Just like the human body...hot will open the iron pores, cold will close up the pores. Also, did you deck, or 'very" carefully check the block deck for being flat ? Mike
I'd read that they tend to not get out of flat and did not check the block deck. But can pull the head (the temperature difference on the passenger side has me thinking that is where the issue is) and check. I can also do my own check of the head for cracks at that time to be sure. Think that is the next step for me?
Welcome from North Carolina. A cool find for sure. Aside from the checking your doing to the motor what is your cooling set up? Is the motor bored oversize or stock bore?
I can't recall the exact specs (wrote them somewhere) but it was bored a bit. Cooling is with an electric fan and a large core radiator (but also don't have the specs on it). When I opened it up, the coolant had crystalized in the aluminum head but I didn't see any in the block. Was going to run Thermocure or Irontite Thoro-Flush, but with the water still spouting from the radiator when revving it, that doesn't seem to make sense right now. And thank you for the welcome!
The heads had manual temp gauges hooked and the lines weren't in the best shape so they were replaced as I wanted to make sure I had good readings. I switched to electric as I wanted to be able to remove and reuse should something like this pop-up again (was hoping it wouldn't be for a while though). I've also been double-checking with a temp gun.
Have you confirmed that you are getting full flow through the radiator? It may be blocked by those "crystals".
I can't be 100% sure but it seems to flow fine. The thought was to get the heads flowing fine, then flush the radiator a few times and test before and after. But with the motor pushing water out the radiator fill when I rev the motor, I think the problem lies elsewhere. There was about a 40+ degree difference in the left and right temp sensor levels when I test-ran it after the heads. I would think it could be a pump issue but then I go back to radiator spitting and think it is something more seal related. I have not yet run another chemical test. In preparation of the worst case, I've called around Denver to find someone who works on flathead. So far, I've managed to find 3 shops that do rebuilds. While not the ideal way to go - knowing that I have resources local to me has been reassuring.
I'm admittedly not a 'flathead guy'. I'm more of an OHV, SBC guy. But what you're experiencing seems to indicate that the water pump is moving the coolant but the radiator is restricting the flow. The flathead radiators and where the pump is in the system are very different animals than I'm used to...... so perhaps someone with more savvy will have a clearer answer.
Pushing coolant out the outlet while revving seems normal to me, pushing it out while idling is not good.
If you are overfilling the radiator it will push coolant until it finds its level. Usually just above the core tubes.
Are you sure it's not just this ^^^^^? The old systems need room in the top of the radiator for the water or coolant to expand. It might also help if you told us what your temp readings are.
It gets up to about 250 rather quickly. I then turn it off. The temperature of the driver's bank is about 190 when the passenger bank is at 250. I have two new water pumps. I am going to run it for a while tomorrow, then do a chem test to see if there is exhaust in the coolant system. If it checks out, I will probably try swapping in the new water pumps to see if that is the issue. The speed at which it goes from 0 to 250 is about what it takes to get to the end of my street and back
If the engine and coolant system is****embled you could do a pressure test to see if holds pressure. Your local auto parts may lend out a tester if you don’t have one. also have you checked for water in the oil, and look for air bubbles in the radiator when idling
No bubbles in the radiator at idle. I haven't done a pressure test but will. I have found that the brand new autometer temp gauges have about a 15° difference which is pretty wild (tested putting both on one side and even swapping then on that one side - one is a quad gauge while the other is a 2-1/8). I've called them for advice and am awaiting a call back. I am going to swap out the water pumps as I have a pair of new pumps. Figure that the worst cas there is that I end up going through a set of gaskets.
You might also switch the sensors from side to side and see if the high temp follows. Maybe one of the pumps is shot?
The left bank on my 8BA runs 10-20 degrees cooler around town and takes much longer during highway driving to come up to 180 degrees, I’v double checked tested my thermostats and swapped them.
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