HELP OVERHEATING 322ci 1938 La Salle Engine!

[Martin Michaels]

Jos1270,you asked at the start of your thread if you can tell if you have a head gasket leak or a cracked block. yes they have a device that can detect gasses in your antifreeze should you have this problem.

[Brad Ipsen CLC #737]

Find Gano filters with an internet search.  The company comes right up

[joeceretti]

These two unpainted pieces encircled in yellow circle, lead air over the front end to engine. These are thin metal and usually rusts away, and results in escaping cooled air downwards away from engine.

I suspect that these are not in fact air scoops but are shields to block road debris and mud from getting into the engine compartment. What effect they would have on cooling I am not sure.

[joeceretti]

The modern logic surrounding time in rad to allow dissipation of heat over a given time does not really apply to the 38 Cadillac flathead. At the engineer spec'd idle the pump just barely pumps the water fast enough to keep it from over heating when everything is at or very near brand new condition. At highway speeds in the hot summer the engine runs just about at a perfect temp. When slowing to a stop after a long run where the entire engine bay has now soaked up tons of heat the temp likes to spike, this is where with these motors you NEED your manual throttle control OR without it you need to keep your idle a bit higher than spec. Slightly above the specified idle, either by adjusting your carb that way or by using the manual control and the engine will not over heat. This is with no inline thermostat.

The temperature control? The rad shutters. These are needed for one purpose and one purpose only. When you drive these cars in cold weather the engine never gets to proper operating temperature. That, and the fact that the passengers freeze to death because the heater just puts out cold air.

A thermostat is not needed in these motors. Restricting the flow of water in any way whatsoever is going to upset the apple cart and cause the engine to overheat. There is not much tolerance for out of spec anything. Too small a rad. Water flow restrictions caused by dirty rad, collapsing hose at the bottom of the rad, people thinking they should put washers or some other restriction in the line because they have been mislead into thinking that the design of a modern or even slightly more modern than 1938 applies. It does not here.

Other things that cause problems are of course, worn impeller, wrong pressure rating on the cap,  too short of a stem on the cap.

[Steve Passmore]

Well, guys, I must be stubborn , or just old school.
For the last 50 years I believe that running without a thermostat will cause over heating.
Sorry, but that's my opinion.

Read item 6 in this link.

http://www.thebriton.com/cool.htm

Na, Rubbish Roy. Wheres the practical proof?   I challenge you to remove your thermostat and tell me what she runs like. I garantee you will get nothing but cold air from your heater and if it were true how would you account for the glaring fact here that Cadillac never even had thermostats as you know it in the water system until 42?    They were there but just to open the shutters and do not restrict coolant flow which they would have to do to apply to your theory.   All 4 of my flatheads have the thermostat disconnected (because they no longer work)and after 100s of miles they struggle to put anything other than luke warm air from the heaters.

[las39]

I suspect that these are not in fact air scoops but are shields to block road debris and mud from getting into the engine compartment. What effect they would have on cooling I am not sure.

Could be. I imagine cooled air is forced to go around engine before exiting around the clutch housing. Anyway, I don't have cooling problem as I live in a cold country. Maybe someone know what their real purpose are.

[joeceretti]

They are for modern design engines to adjust flow to keep the internal temps within acceptable operating range. Adjusting water flow and cooling up and down to keep it right.

Oh, the scoops. Cadillac call them mud pans.

[Brad Ipsen CLC #737]

Talking restrictions in water flow in flat heads whatever you do, do not enlarge the outlet hole on the right head which is smaller than the hole on the left.  This restriction is necessary to balance the water flow between the left and right banks.  Since the water pump is only on the right side most of the flow would stay on the right side if it did not have the restriction to flow on that side.  This is one of the pitfalls of using the military heads.  The water outlets were at the back of the engine so when these heads are flipped around for a car the right side does not have the smaller hole at the outlet.

[jos1270]

Hello guys. I ordered the 1937 1938 Cadillac and LaSalle shop manual and just got it. I was looking through it to see what size core  my LaSalle had to have and it says the the thickness of the core has to be 3". This is  suppose to be for 38-50 & 60 series and as far as I know mine is a series 50. So what I am thinking is that I am going to have to get inside the engine and clean it as best as possible.

On that note, I have been reading other forums on how to get rust out from inside the engine. And I came across with a weird way of get rust out. Have you guys every heard of rust removal with molasses? This is suppose to be an animal feed and it can be purchased at any agricultural supplier. There is different mix ratios that I have seen. But the one I see the most is one part molasses and nine parts water. Depending on how rusty the parts you are trying to get the rust off, you may have to leave it for 2, 3 weeks. Some forums even say a month or month and a half. Now this stuff is suppose to be really safe. It has no acids or crazy stuff to harm you the environment or the engine. The only thing this does is get rust off. You guys can look it up on youtube.com.

I was thinking of doing this, but im still a lil scared that this might do something to the engine that I may not want done. I was also thinking that since the head bolts go through the heads and into the water jackets then this may help get some of the rust off the bolt, if it does have any, to see if I can take them off. I say this because in on of the videos I seen it shows a really rust part with nuts and bolts and after being inside the stuff they came off with no problem.

What do you guys think? GOOD IDEA OR BAD IDEA?  I know it sounds crazy but I don't want to brake head bolts if I can prevent it, and well this seems like a good idea.

Thanks in advance to all, and certainly for all the great information.

[jos1270]

  I forgot to add that I would have to fill the engine block only with a nine part water and one part molasses. After that I would take out the freeze plugs and try to use a pressure washer to get rust and all the gunk that would be in it. Then use some of that Gano Filters I was recommended in this forum to keep the radiator clean.

[joeceretti]

I don't remember if anyone asked about your lower rad hose. Normal heating at speed can sometimes cause this hose, under vacuum, to collapse and restrict flow only exasperating the problem causing further collapse. You could try coiling up some wire so it's a slightly snug fit and inserting it into the rad hose to prevent it from happening. With the hose, everything may seem fine but after driving it may heat up and soften somewhat allowing this to happen. If you feel the hose when cool it may seem just fine.

It's something you can try that is fairly easy and inexpensive to do.