DonMicheletti

Pressurizing the system does not prevent overheating, all it does is raise the boiling point of the coolant. I'd describe overheating as any time the temperature of the running engine gets over the set temperature of the thermostat, regardless of operation. Temperature rise can occur after an engine is shut down. I can't comment on the effectiveness of an IR thermometer. There is so much iron mass in a block that I doubt that it would be able effectively indicate exact temperatures at the inside of the water jacket and the cylinder surfaces - where the heat transfer actually occurs. By the way - I have never had a Buick reach 200° All bets are off on modified engines.

I have had old Buicks since 1960. 1910, 1918, 1931, 1932, 1936 (2) and 1965. I drove them in all kinds of weather and terrain. The only time I ever had heating problems, dirt in the cooling system was the culprit. I never resorted to modifying the cooling systems. Our weather around here doesnt get as hot as Los Vegas - but my cars have seen heats of over 100° with no issues - and on long hills. You make a point about changes in design - but most have no affect on cooling. One of the major problems of an "open" cooling system is that the heat does evaporate some water, leaving dirt behind. Refilling does add some dirt. That cycle repeated for years will leave considerable crud in the water jacket. Getting the water jacket clean is of paramount importance and it often isnt done. I have experienced that crud buildup in all of the old Buicks.

You can be assured that when these cars were built, they didnt run hot when driven at reasonable speeds (whatever that might be) in any temperature environment. Buick would not have built that same engine from '36 to '53 if it had a problem with running hot - they would have been out of business.

In spite of the fact that yours is a low mileage car, there is no guarantee that there isnt a bunch of crud in the block. It is over 70 years old. As often as not on these engines, dirt and scale in the block is the cause of the engines running hot. If that is the case, nothing else you do will cure a running hot problem. As big a job as it is, knocking out the core (freeze) plugs and mechanically scraping the water passages out would be the only cure.

Menlo Park is midway between San Francisco and San Jose, California

As always, I suggest going through the old Torque Tube magazines. There were several performance enhancement tricks noted. Taking 1/8" off the head is a quick and easy way to get the compression a touch up to take advantage of todays better gasoline (no bitching about ethanol please). Remember, you are driving an old car and it wont match your new Toyota no matter what. My stock (I believe) '38 Roadmaster gets 11.3 mpg on the road, but performs and accelerates well and I am satisfied with that. I'm old enough to remember the Centurys at the drag strips dusting flat head Fords - both of which were cheating like heck! There is lots you can do to a big Buick engine to make it a real performer, but the stock manifolding is a real negative

Dont forget to check the switch to to be sure voltage is getting to that. Also that switch is over 75 years old too and subject to contact oxidation. It can be disassembled to clean up. Diagnosis is everything. Another thing, there is a plug behind the dash that connects the front end wiring to the rear wiring. There may be oxidation of the contacts there too. Since yours is a low mileage car, that is no guarantee there can't be electrical gremlins just due to age and unuse. Good luck, it can be a PITA.

It has been many years, but my '31-67 had no such fuel pump. It was a single stage pump and the car was only 29 years old when I got it.

That is why they used to make "winter fronts". A sheet to block part of the radiator.

Often bad grounds are a problem with the dome light. If you look closely at the left photo, you can see a screw head just to the right of the light socket for the ground wire. Even on that part there is significant corrosion. I forget what the ground wire attaches to on the body. Also, the positive terminal for the bulb in the socket is actually a screw that pinches the feed wire via a special nut the wire goes through. That screw can come loose and loose contact. The upper assembly is held in place via 4 wood screws and can easily be removed to check things out and see if you are actually getting voltage to the bulb.

Here i8s a photo of the 46S dome light assembly

I have a '38 46S. It just pries down. The lens is round. There are 4 "tabs" on the top part that hold it up. I'd believe the sedan is the same

Well, A bigger engine will make it go better - but that stock braking system makes it a death trap!!

I have had '38 Buicks for over 30 years. They do not have a rear main seal and oil leakage has not been a problem. However if an engine is really shot ant there is a lot of blowby, then there may be a problem of oil leakage. It worked before, it will work again.

I had a '32 - 56 that ran hot when I bought it. In place flushing it didnt help. I removed the radiator, turned it upside down and flushed it that way. The amount of crud that came out was incredible. The car ran to cold after that until I got the radiator shutters working properly.

The old Torque Tube Magazine had lots of information on rebuilding these engines. Look around here. http://www.1937and1938buicks.com/The-Torque-Tube/Torque%20Tube%20Technical%20Index%20By%20Frank%20Freda.pdf And here http://www.1937and1938buicks.com/The-Torque-Tube/The-Torque-Tube.htm It is possible to adapt a modern full flow oil filtration system without making it to obvious, but it is a major job. A partial flow oil filter is simple. With the stock restrictive manifolding, both intake and exhaust, I'd think twice about raising the CR ratio to much.

Fixing the heater motor is not a big deal. Take the motor apart. That will allow you to check the condition of the shaft bearing area and also check the condition of the brushes and commutator. It will also allow you to oil the bearing that is in the blind end of the motor. I believe these are oilite, so just oiling the bronze bearings isnt going to last forever. I have been lucky on mine. The brushes were good, so I just cleaned up the commutator, oiled the bearings and it turned out OK. I did my '38 Roadmaster about 30 years ago and it is just now starting to make noise again - I'm OK with that. Don

Pull the valve cover and check for stuck valves. Not an uncommon problem.

Bottom line... if the heat doesn't get out of the block into the water, all the front end work (radiator, fans & etc) is money down the drain!! Remember, Buick built cars that did work many years ago. While traffic is different today, thermodynamics has not changed.

The '38 Roadmaster has a similar center idler arm I believe. Slop in that idler arm is a steering problem. I rebuilt mine many years ago (30+) and I remember it being a real pain to repair. If I remember correctly, the pin has to come up and the engine is in the way. At the time, the engine was out of my car so that was no problem. I don't know if you can lift the engine enough to get that pin out. Once I got it apart, the bearings resembled a bicycle wheel bearing and everything was toast. I ended up machining the arm to take 2 light series sealed ball bearings that were the same size bore as the pin (which was in OK condition).. If the pin is chewed up too, you might have to machine a new one. Over 25 years later,it is still working well. The best of luck. I wish the US had mechanical inspections like the Europeans do to insure cars are mechanically safe. All they seem to care about here is if the pollution is in spec! (I did live in Europe once) Don

Just 90 wt, hypoid oil you can get at any parts store is OK

There is no need to "adjust" or grind anything - the engine has hydraulic valve lifters. The parts are machined so the lifters do all the adjustment.

If the rivets are not loose you can do what is called " caulking". That is where you get a round nose punch and pein, using the punch and hammer, the area of the leak. It is surprisingly effective. It will also work at the joint where the axle tubes meet the center housing. You would pein the edge of the head rivet where it meets the holding surface. This method is commonly used on riveted steam boilers to seal small leaks.

You just need a propane torch to get the copper to red hot. (you can even di it with a cigarette lighter) You do not need to worry if the ring gets distorted. Since it becomes dead soft, the process of tightening will flatten it out. The idea behind the annealing is to make it very soft so it will conform to any irregularities on the sealing surfaces. However, the smoother the better. You do not have to worry about the copper getting to soft and blowing out. It still has plenty of strength

First, the sealing surfaces must be smooth. Then you have to fully anneal the copper seal ring. You anneal the ring by heating it until it is fully red hot and then quench it in water. Taught to me by an old pipe fitter. Some say that you do not have to quench it, but I always do and it always works