Sonomatic

JohnD1956, Is this your Super? I'm here in Morgantown and I saw it when I checked in. This is my favorite car I've seen here so far.

What a great looking car! Yeah, we need a few more shots of this beauty

What happens with the flasher when using leds?

For some reason I thought you had a 263, sorry. What adapter you using on your 248?

The vacuum modulator is a vital component of automatic transmissions. It tells the transmission what kind of load is being put on it, allowing the transmission to react with the proper line pressures and shift points. Because of this, you want your manifold vacuum source to be soley manifold vacuum, not a vacuum signal enhanced by the vacuum function of the fuel pump. It’s original purpose of the vacuum/ fuel pump was to “cover up” the low manifold vacuum during acceleration. This low vacuum during acceleration is exactly what tells the vacuum modulator on your TH350 to increase line pressure for firmer shifts and also tells the transmission to raise the shift points for better acceleration. The kickdown linkage is what tells the trans to drop to a lower gear for acceleration such as when passing. Later model transmissions used a TV cable which took over the function of the vacuum modulator and kickdown linkage as EmTee stated. As for the line for the wipers, if you’re not using it, cap it off, otherwise , it’s the same as a vacuum leak. What adapter did you use to mate the 263 to the TH350?

That is a good looking car. As was mentioned, rusted floors and rockers are suspicious for an Arizona then Texas car. Still, very good looking car. I've always wondered how solid a 4 door hard top would be. They are every bit as attractive as a 2 door. Also, I thought I saw something in the forums about some weird, 1 year suspension on these '57's that makes it very expensive to restore the front ends on these. Still, if it were closer, I would certainly go have a look, and, if those bumper ends and the trim were there, I think I'd have to bring that home. Sadly, 55er brings up a harsh truth, it is getting prohibitively expensive to rescue these old gals.

Great pictures, great info, great post. Thanks for sharing this!

So this morning I was admiring JohnD1956's '56 Super and ran across some information he found in his service manual and posted in regard to some charging troubles he was having, ' The manual though, is very clear that anytime you disconnect the battery you need to polarize the generator before starting the car or you could damage the regulator. So it would appear that my failure to polarize the generator for the last ten years may have been the root cause of my situation." How about that. Also, on John's recomendation, I;ve started pricing wiring harnesses, they cost as much as the car did. Will need to do something.

I have such a hard time understanding the '55 Chevy thing when Buick had these. But that seems to always be the case, Buick makes a few, they're gone, and then everyone finds out how great they were. Compound carbs on the straight eights, these '55 Centuries, the GS cars, dual quad 465's, the Grand National....why is this?

That is really interesting. I don't think of the manufacterers as knowing anything about handling until the late 70's. I had a few Mustangs, and couldn't believe the difference when I bought a new Trans Am in '78. I will say, this '50 Buick is making me a believer. Not that it goes around corners well, but how it drives on less than perfect dirt and gravel roads. It rides remarkably well in such environments.

Dan O, you said it! Cruel. Looks like wiring will cost as much as the car did. Further, looks like a ready made harness is cheaper than trying to source wire and do it your self. Frank DuVal, I'm with you, I was sure the regulator was bad, but, on a whim, did the polarizing proceedure and it's working normal.

Yes, the wiring harness has certainly seen better days, and, although I don't have a kill switch installed, the negative battery cable is just slipped on the battery post. I will also take your advice as to disconnecting the battery when it's inside, which is always. The harness is on the list, I had intended to query the forum and see where the best harness could be obatained, particularly the correct gage of wire. I would not be opposed to modern insulation but would like a harness with original gage wire. I am also interested in mobilparts' comment. I wasn't aware that you offered parts. Do you have a website or catalog?

So some of you may have seen my post on replacing the front pump seal on the Dynaflow in my '50 Special. After being down for two months, I got the car back together and noticed that the generator was severely overcharging. I didn't remember having that problem before. Looked in the service manual and found that the regulator can be adjusted for output. Yeah, maybe the original could, but the one installed now has no adjustment. I figured, old car, always need something, so I ordered a new voltage regulator from Kanter. In the mean time, I decided to drive around with the headlights on so as to not severely overcharge the battery that was already long in the tooth, (the previous owner told me it was from 2017 I think). I stopped by a freind's house to show off my recent repair, sat on the porch and chatted for an hour and a half, went to leave and, you guessed it, battery dead as a door nail. Home was withing walking distance, so, I went and got my battery charger and hooked it up for an hour or so, nothing doin'. Plan B: found a battery, in stock at Tractor Supply. Went and got the battery, set it on the ground next to the car, hooked up my jumper cables and she lit right off. Through the battery in the trunk, and, with a red face, drove my Buick home. Next day, I put the new battery in, and, found in the service manual the proceedure for polarizing the voltage regulator, or, is it more corredt to say, polarize the generator. Anyway, manual said, take a screwdriver and momentarily jump the generator and battery terminals on the voltage regulator. Terminals in the first picture, from top to bottom are FIELD GEN BATT. Second picture shows jumping GEN and BATT terminals with Screwdriver. Now the generator is charging as before, and, now I have a spare regulator on the way for $110. I've heard about this proceedure of polarizing the generator all of my life, but have never had a car that required it. A lot of you with experience with these regulator controlled charging systems probably figured out what my problem was right away. That's why we need this forum, to keep all of this knowledge alive. Thanks to all of you that do just that.

Thank you gentlemen. I've been driving around town, using it to run errands and such. I've got about 65 miles on my repair, and, so far so good. I want to drive it to some of the local shows and such and figure out what it needs and I'll do those things this winter. My biggest worry right now is getting rear ended because the back of the car doesn't light up like Xmas like new cars do. There was a guy with a '50 Sedanette down in Florida, doing videos on Youtube who got rear ended. Haven't seen anything about the car since.

Today I got to drive the Buick. No leaks, works really well, as it did before I removed it to replace the front seal. I also replaced the entire exhaust system, new shock links in the rear, new trans mount, new trans thrust mount, new polyurethatne Panhard rod bushings as recommended by Old_Tank. New master cylinder. New heater hoses. Should be able to make some 50 mile trips and not worry too much. Lots left to do, but now we're into cosmetics, not roadworthy things. I kind of fell off at the end with the pictures and such. This was not a really hard task, but I still wound up taking slightly over 2 months. I need to keep taking small, bite size projects to keep this care on the road and keep it from turning into another basket case that winds up scattered all over my garage and never gets put back together. I plan on driving it to local shows and get to know the local Buick folks. I think I've got a fun summer ahead.