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My 1949 23rd series, 288 cubic inch engine is running hot when idling. I have had the radiator re-cored, installed a new water pump, had the water distribution tube removed and during removal had the center of the block power washed until clear water ran from the thermostat channel.

A lot of gunk came out during the power wash.

We let some of it come out of the front of the engine and some come out through the thermostat housing area.

But then the water ran clean.

Still the engine runs hot when idling in mildly warm weather (85 degrees ambient)

At this point, is it worth pulling the head? Are there any ports in the flat head that may be restricted and not be allowing good flow of cooling liquid?

I am not sure of the return path of the liquid once it runs through the water distribution tube and I am thinking that the flat head may have some restrictions.

I would appreciate any comments.

Well, first things first, are you sure about running hot, might sound like a dumb question, but how accurate is your reading.
Next when was the last time you checked your timing?
Since you flushed the system, did you check the Thermostat?
Try this first, okay.
Wes

Honestly, in my experience a tendency of overheat or at least run hotter especially at idle in traffic has become a common occurance of the 22nd and 23rd series Eights and Super Eights (but not the Custom 8s) as they have become older. I doubt they did it new except in really strenuous conditions but cooling systems degrade slowly and rather constantly over time and I'd guess these models had less excess margin of cooling capacity than other postwar models. First thing I'd do is get a correlation between the position of the temperature gauge needle with respect to the true temperature by using a good quality thermometer in the top of the radiator tank with the engine running. If you are really running more than 15-20 degrees above the thermostat setting I'd start looking at all the normal but sometimes small things that can contribute before I tackled the major things like radiators and water pumps, system cleanliness, etc., - things like ignition timing, undersize or restricted exhaust systems, incorrectly sized or tensioned fan belts, fan blade to radiator core clearance, excessively thick paint on the radiator core, lean fuel mixture (e.g. from a vacuum leak), and more.

Thank you. Yes, I checked the engine with infrared gun to make sure about the temperature and the thermostat is new

I also checked the timing and it is good.

I guess my main question is, since there was so much gunk that came out when we washed out the chamber with the water distribution tube, are there additional channels or chambers that might also be clogged that we could not get to from the flush in the center of the block. Could I get to other areas by removing the head?

I cannot figure out how the water flows after it leaves the water distribution tube. I realize that it flows around the cylinders but if those channels are clogged, will removing the head allow us to see other areas that might be preventing the flow of cool liquid? Does liquid flow through any ports in the head?

I don't know if this would matter, but did you do a back flush. I would try anything before removing the head, also what type on coolant are you using? Also see this from Mr. Kanterhttps://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?topic_id=16042&forum=4&post_id=160961#forumpost160961
Wes

There are numerous water pathways involving holes and slots in the block which mate with corresponding areas in the head. After leaving the dist tube whose primary function is to ensure cooled water is directed first onto the valve seat areas it is disbursed in several directions thruout the engine -- back across the cylinder walls for one and up into the head for another. Once in the head it again goes across and travels the length until it reaches the exit point where the thermostat resides and then into the top of the radiator.

It is conceivable there is more crud in the engine and also in the head. Without removing the core plugs and prodding any scale on the drivers side of the engine it is hard to estimate how much might still be remaining in the block. The head has no cleanout areas other than the holes and slots which mate to the block so possibly some scale has deposited there. I don't believe any of the holes are larger than maybe 3/4" so if any scale has built up around the holes it could restrict flow.

Does liquid flow through any ports in the head?

No doubt you've noticed the thermostat housing (water outlet) is on the cylinder head so yes, the head is a honeycomb of water passages. But as Wesley suggests, I'd hesitate to remove it until you've tried the usual chemical cleaning treatment (oxalic acid, followed by a neutralizer) and perhaps a power flush of the system. Try to borrow a flushing gun like this one and use it on the engine block and head assembly, flushing in reverse direction of the coolant flow. Then perhaps repeat the oxalic acid treatment until the coolant drains colorless.

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Good afternoon...Dolores and I have a 1949 2362-288 'Miss Prudence' and when we first purchased her, she ran hot...above 220 which really concerned me. The radiator was really ugly, so we had a new one made here in Phoenix, and added a more efficient fan while the radiator was out. We even went to a 141 degree thermostat from NAPA(Part-18-3551-Line-SME) as discussed in an old service memo that we found on this site or the Packard Club site. Our Muffler and tail pipe were incorrect, too small, so we replaced them. We also rebuilt the water pump at this time. If your block was clogged, then I would expect that your Radiator is also clogged and needs to be at least flushed and flow tested. We found that our distributor was not working properly, the bearings were sloppy and the vacuum advance did not work. We purchased a rebuilt distributor and vacuum advance and it helped. We also removed the head and found that the gasket had failed and that there was leakage between the four center cylinders. We also found that our head was not flat and we had it decked before we put it back on the engine. More junk was removed from the head and engine when the head was off. Cooling improved. We also found a product called '40 Below' which is a racing coolant that you can order from Speedway for about $25.00. It also helped. It helps to run the correct spark plugs, gapped properly. Deluxe Canuck, who has the same machine as 'Miss Prudence, added a radiator shroud of his own design and reported that it also helped. I just fabricated a shroud somewhat based on his design, and finished installing it two days ago. I have not had time to really test it, but there is definitely more air moving over the engine now. 'Miss Prudence' now runs like a Packard should!

Once your 'old girl' has had benefit of lots of love, she will run fine and give you lots of fun. These old girls are somewhat like going back to high school or college and visiting an old girlfriend!

Ernie

These are all great inputs. Thank you all!