Coupe 31

[Coupe 31]

Hi to All Buick friends

i signed up today

I recently purchased a 31 66s coupe just like some of you own. I have observed some of your threads and you are very knowledgeable custodians of this type of iron. This is my first 30s car, I have grown up with a 55 Chevy.

 

On my first drive in the car (20 miles ) it overheated twice and I had to stop.

the radiator slats did not open. I tried to jimmy it open but the spring was very strong. I am also noticing some whitish oil floating in the radiator.  Could this come from the thermostat below liquid? (Or maybe the oil cooler  is failing?

no water in crankcase oil.  The car was restored 35 years ago and has sat for 30 years without use.  It was only driven 36miles after the restoration then sat for all those years, but since owner passed I

 

i hate  to take it all apart as it was a very nice frame off restoration.

i need to change the oil too and would like to know if I should use non detergent and multi grade. Since owner passed I have no history on its maintenance.

 

any ideas would be very appreciated.

 

 

thanks

andy

  

 

 

 

 

[Coupe 31]

Looks like I may be in the wrong forum.  Buick’s  pre war?

[Dave39MD]

Welcome,

 

You can prop open the shutters mine is that way until I get the stat rebuilt. Most have the oil temp regulator by passed by now. Send us some pictures of the passenger side engine compartment, and you car too!

 

Oil is an interesting discussion which will have many opinions. I am using a high grade 10w-30 detergent oil and my oil pressure is fine.

 

Great car!

 

Dave

[Coupe 31]

Thanks Dave

how do I send pics on this site?

[Dave39MD]

When you click on the reply button a box will open and at the bottom it will have an underlined choose files. Click on that and follow the instructions. Mine goes right to my picture files on my computer, yours may be different.

 

Dave

 

 

[1939_Buick]

32 minutes ago, Coupe 31 said:

Looks like I may be in the wrong forum.  Buick’s  pre war?

Yes.  Better to re post in pre war Buick forum

https://forums.aaca.org/forum/60-buick-pre-war/

 

I would not have driven a car that sat for a long time

 

This thread may interest you--->https://forums.aaca.org/topic/274240-1931-buick-roadster-oil-temp-regulator/

 

[Coupe 31]

Dave we almost have same color just different wheels

[Dave39MD]

Very nice, thanks for posting. Dave K is also restoring one here; 

Great cars

[Coupe 31]

Thank you 1939_Buick for link to the oil cooler. Very educational. Will run car a few times to see if maybe gaskets will seal better and will check for loose bolts

 

can you tell me how to copy and post my original post in the pre war Buick  site. Not computer savvy  and This is my first experiece with forums so I’m very green

 

thanks a lot

[Str8-8-Dave]

Just seeing this thread today- where have I been...   Coupe 31- congrats on a very nice car.  The root cause of the radiator shutter not opening is a dead thermostat which is under the ring of screws on the back side of the upper radiator tank.  Like Dave Dunton said for now you can prop the shutters open but I would caution disconnect the link that connects the radiator shutter to the thermostat bellcrank.  Then it will be easy to prop the shutter open.  The thermostat is a Sylphon bellows type thermostat consisting of a brass can outer housing and sealed bellows with a link.  The can has formaldehyde or alcohol and water mix inside to expand and contract as the coolant in the upper radiator tank changes temperature.  It normally opens at about 145 degrees and is wide open at about 160.  Hopefully someone else had the screws out of the ring that holds the thermostat in the top tank of the radiator in place sometime in the last 30 years or you will have trouble getting the screws out, especially with the radiator in the car.  If you look at my restoration thread scroll down to the last post on page one and you will find all kinds of radiator and thermostat fun stuff.  Let us know how you make out with your car.

 

Dave Krugler

Port Huron, MI

 

 

Bellows side of thermostat

 

The brass housing has some alcohol, methanol, formaldehyde, water cocktail inside with air removed by vacuum to compress bellows when cold then

expand rapidly when heated by the coolant in the upper tank.  There are guys around that service these thermostats.  The effective service method is to replace the bellows outright as they become work hardened and eventually crack and leak the reactive chemistry out of the housing causing the

thermostat to fail.

 

For now to prevent overheat remove the pin indicated by the arrow which should free up the shutters and prop them open. 

Edited May 22, 2021 by Str8-8-Dave (see edit history)

[Mark Shaw]

I found this somewhere on The Internet. 

Sorry; I didn't capture the author.

 

Buick Thermostat Bellows Repair

 

These are fairly easy to repair. Perform an air leak-down test using 5-10 pounds of air. If necessary, solder the repair which is usually a crack in the bellows section. When disassembled, use bright light against the suspected section to see the leak area. After soldering together, fill the unit half way (and I mean only half way) with Methyl Alcohol using the "soldered over" fill area in the rear of the unit. You can also replace the soldered fill hole with a machine screw and nylon washer with sealant. Using the machine screw method also makes it easier to perform the leak-down test. Methyl Alcohol is used in some brands of Dry Gas products, so read the labels carefully. I found mine at a local Rite Aid drug store. Do not use Ethyl or Isopropel alcohol. Test the unit in a pot of boiling water before reinstalling.

Cost of Solder: $2.50

Cost of Dry Gas: $2.99

Repairing it yourself: Priceless!

[Coupe 31]

Thank you 1939_Buick for link to the oil cooler. Very educational. Will run car a few times to see if maybe gaskets will seal better and will check for loose bolts

 

can you tell me how to copy and post my original post in the pre war Buick  site. Not computer savvy  and This is my first experiece with forums so I’m very green

 

thanks a lot

[Coupe 31]

Straight 8 Dave thank you so  very much for this invaluable information on the thermostat device

i feel  now I will be able to tackle this little problem over the summer.  The thermostat repair may be over my head but I can try to prop shutters open for now.

”

when the car overheated I pulled out that cotter pin that you showed on the diagram but there was still a strong spring holding the shutters closed.  I had no small block of wood to prop that open, so in 20.miles I had to shut car down twice when gauge got close to 200 degrees.

 

people like you make it a pleasure to own these cars which otherwise would be  a frustrating undertaking depending on $100/hr mechanics  that have no experience on these cars.

 

very grateful

andy