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gjamesk
05-18-2018, 01:17 PM
I'm still sorting out my 52 Commander Starlight. Normally when driving around town the OD works fine. However after driving yesterday on the highway at 65 for about 15 miles, when I turned around to come back home it would not drop into OD. As this car has the 4.55 rear axle not having OD makes for a noisy, busy drive even at 60.


I've had this happen once before, again on an extended drive when the car was hot. Any ideas as to where I should start looking for the problem?

Jerry Forrester
05-18-2018, 02:24 PM
I'm still sorting out my 52 Commander Starlight. Normally when driving around town the OD works fine. However after driving yesterday on the highway at 65 for about 15 miles, when I turned around to come back home it would not drop into OD. As this car has the 4.55 rear axle not having OD makes for a noisy, busy drive even at 60.


I've had this happen once before, again on an extended drive when the car was hot. Any ideas as to where I should start looking for the problem?

The fuse....

RadioRoy
05-18-2018, 02:27 PM
Check the governor to see if it is full of oil.

Bud
05-18-2018, 03:14 PM
I agree with Roy. Oil works its way past the governor shaft seal and contaminates the contacts in the top cover of the governor which will cause intermittent overdrive operation. The governor is easily removed from the right side of the transmission for cleaning. I've had to do that numerous times over the years with my overdrive equipped cars and trucks. If you clean the contacts be careful with any abrasives as the contacts can be easily damaged. Bud

StudeRich
05-18-2018, 03:28 PM
Not sure if this would cause it, or help but I have ask: are you running GL-1 non-extreme pressure 90 Wt. Gear Oil?

gjamesk
05-18-2018, 04:37 PM
The fuse is good, as is a recent drain and refill with the correct lubricant. I'll pull the governor in the morning and report back. Thanks for the tips.

Ross
05-18-2018, 04:42 PM
Have often found excess resistance in the relay being the cause of hot failures. The different plates and contacts in the relay were held together with brass rivets. Here 65+ years later the rivets are corroding under their heads or the heads have popped off completely. Drill them out and replace them with little brass screws and nuts for another 65 years of trouble free service.

Xcalibur
05-18-2018, 04:44 PM
Been way too long since I had anything with one, but does it have a solenoid in the system? Sounds like what a bad one sometimes does, works when cold but not when hot.

TWChamp
05-18-2018, 06:45 PM
Two Studebakers, in fact it was the first one and the last one I bought, didn't want to engage all the time. The first one I had to remove the relay cover and clean the contacts because the old lady never got the car fast enough to engage the relay. The Land Cruiser I just bought worked fine after I test drove it a couple miles and let the relay click in and out several times. It worked flawlessly for over 600 miles on the drive home.

gjamesk
05-20-2018, 03:44 PM
I cleaned out the governor, a little dirty but not bad inside, contacts seemed okay. Cleaned the contacts in the relay. Drove the car yesterday 30+ miles to a Grand Canyon State chapter event and the OD worked fine. Left after about 3 hours and the OD would not engage. Drove it home that way.

This morning I went through the troubleshooting flow chart in the manual "Transmission will not engage in overdrive". First step is to ground the governor wire and check that the relay and solenoid 'click'. The relay did but the solenoid did not. Followed the rest of the steps and everything else checked out fine. Buttoned it up and took it for a drive and the OD engagement was normal. :(

Back in the garage I grounded the governor circuit and heard the relay AND solenoid click. Immediately did it again and no solenoid click this time, or with subsequent tries. So seems to me the solenoid is likely the issue. Opinions? Since a new solenoid is $225 I don't want to buy one needlessly if that's not the problem.

Ross
05-20-2018, 04:55 PM
You can easily check your solenoid by powering it directly at the relay terminal.

If it is giving intermittent service, thee is a set of contacts inside the solenoid that need to be cleaned. There are tow magnetic coils inside, one for pulling in, and one for holding in. The pull-in coil is powered by a set of points that are snapped open as the solenoid reaches its cocked and ready to go position. If you take off the cover of the solenoid you can see them about half way up the housing. Give them a good cleaning before dropping money on a new solenoid. The other contacts on the top of the solenoid are for grounding out the ignition for kickdown.

TWChamp
05-20-2018, 05:45 PM
Also be sure the wire from the relay to the solenoid is good. If you need a solenoid, I'm sure someone here, or French Lake would have a good used one.

gjamesk
05-21-2018, 03:39 PM
I opened up the solenoid and cleaned it. Pretty dirty inside, looks like the leather(?) seal in the top has deteriorated. Has anyone replaced that? I replaced the solenoid shaft seal in the tranny recently so I shouldn't get much new oil in there, but that upper seal isolates the solenoid engagement points.

I'll give it an extended drive to get it hot and see what happens. Hopefully cleaning the solenoid has fixed it. Thanks for all the help.

jackb
05-21-2018, 08:34 PM
when the OD "is" operating nicely, do you get "kickdown" to conventional high gear ?? Might be another clue as to the switch's integrity. Those posts do vibrate over time and can behave intermittently...