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View Full Version : Auto trans. buzz in Park & Rev.



Milaca
07-14-2006, 05:39 AM
Good day all from central Minnesota! I recently purchased a 1964 Daytona hardtop with V8 & automatic transmission. When the selector is in Park or in the Reverse position, a loud buzzing noise comes from the tranny. It sounds similar to an electronic warning buzzer.
Any idea what this might be?
The car runs & drives fine, although I may need to adjust the carburetor/trans linkage rod as it doesn't shift into high gear until it reaches 60 mph. Any advice would be appreciated.
Thanks, Brent

gordr
07-14-2006, 06:45 AM
quote:Originally posted by Milaca

Good day all from central Minnesota! I recently purchased a 1964 Daytona hardtop with V8 & automatic transmission. When the selector is in Park or in the Reverse position, a loud buzzing noise comes from the tranny. It sounds similar to an electronic warning buzzer.
Any idea what this might be?
The car runs & drives fine, although I may need to adjust the carburetor/trans linkage rod as it doesn't shift into high gear until it reaches 60 mph. Any advice would be appreciated.
Thanks, Brent


The buzz is the pressure regulator valve in the transmission. It's buzzing because the throttle valve linkage is out of adjustment, which is the exact same reason you are getting late upshifts.

I'll bet you a donut that the left side tranny mount has become oil-soaked, and has sagged down, which acts to move the tranny back, and effectively "shortens" the throttle valve linkage. It is almost a given that this will happen on a well-used Studebaker.

BTW, the linkage rod in question runs from the lower arm on the throttle bellcrank at the back of the left cylinder head, back to the throttle valve lever which shares the same axis as the manual shift valve in the tranny. Lengthening this rod at the clevis will stop the buzzing, and lower your shift speed...BUT, when you do eventually replace the rotten mount, you'll have to adjust it all over again. If you replace the mount(s) now, the linkage rod should wind up needing only minor tweaking, if at all.

If you go to the home page of this site, there is a link to a vendors page. I'd recommend that you replace all 4 mounts: 2 under the bellhousing (the expensive ones) and the two near the front of the engine. It's not all that hard to do, and shouldn't set you back more than $150 or so. And they ARE a safety-related item. If you're going to get dirty for one mount, and you will (ask me how I know :D) you may as well do 'em all at once, and be done with it.

This should be made one of the tech FAQs, because it gets asked so often!

Gord Richmond, within Weasel range of the Alberta Badlands

ROADRACELARK
07-14-2006, 07:32 AM
Brent,
First check the fluid leval.. do it with eng/trans warm, on level surface, trans in drive, emergency brake set or wheels chocked. Also as advised, check those mounts. If they need replacing, do that before making the adjustment.:) HTH
Dan

Road Racers turn left AND right.

Milaca
07-15-2006, 01:31 AM
The buzz is the pressure regulator valve in the transmission. It's buzzing because the throttle valve linkage is out of adjustment, which is the exact same reason you are getting late upshifts.

I'll bet you a donut that the left side tranny mount has become oil-soaked, and has sagged down, which acts to move the tranny back, and effectively "shortens" the throttle valve linkage. It is almost a given that this will happen on a well-used Studebaker.

BTW, the linkage rod in question runs from the lower arm on the throttle bellcrank at the back of the left cylinder head, back to the throttle valve lever which shares the same axis as the manual shift valve in the tranny. Lengthening this rod at the clevis will stop the buzzing, and lower your shift speed...BUT, when you do eventually replace the rotten mount, you'll have to adjust it all over again. If you replace the mount(s) now, the linkage rod should wind up needing only minor tweaking, if at all.

If you go to the home page of this site, there is a link to a vendors page. I'd recommend that you replace all 4 mounts: 2 under the bellhousing (the expensive ones) and the two near the front of the engine. It's not all that hard to do, and shouldn't set you back more than $150 or so. And they ARE a safety-related item. If you're going to get dirty for one mount, and you will (ask me how I know :D) you may as well do 'em all at once, and be done with it.

This should be made one of the tech FAQs, because it gets asked so often!

Gord Richmond, within Weasel range of the Alberta Badlands
[/quote]
Thanks for your response. The previous owner did mention that he recently replaced the front engine mounts but I dont recall him mentioning the tranny mounts. I guess it would make sense that if the front mounts are bad, then the back mounts would need replacing too. As for a mount being oil soaked, I'm sure it is! The rear main seal marks its territory every time I park it in my garage by leaving a puddle on the concrete! As for tranny fluid level, I checked it properly and it is good. By the way, I recently purchased a new pan gasket and filter screen from NAPA so that I can change the fluid one of these days.

showbizkid
07-15-2006, 09:24 PM
quote:Originally posted by gordr

If you go to the home page of this site, there is a link to a vendors page. I'd recommend that you replace all 4 mounts: 2 under the bellhousing (the expensive ones) and the two near the front of the engine. It's not all that hard to do, and shouldn't set you back more than $150 or so. And they ARE a safety-related item. If you're going to get dirty for one mount, and you will (ask me how I know :D) you may as well do 'em all at once, and be done with it.

Hey Gord, this brings up a real dumb question :D Can you replace the mounts one-at-a-time with the engine and trans still in the car, or do you have to pull them?

---------------------------
Clark in San Diego:

Proud new owner of a '63 Lark!

gordr
07-16-2006, 02:17 AM
Hey Gord, this brings up a real dumb question :D Can you replace the mounts one-at-a-time with the engine and trans still in the car, or do you have to pull them?

---------------------------
Clark in San Diego:

Proud new owner of a '63 Lark!
[/quote]

Easiest, IMHO:
With the car securely supported on jackstands, remove the nuts from the lower studs on both tranny mounts. Then "crack" the bolts holding the mount brackets to the bellhousing. Use a floor jack with a plywood pad to raise the tranny by carefully jacking under the pan. It'll only go up a bit less than 2 inches; don't force anything. With the tranny supported, back out the bolts holding the mounts to the bellhousing, and remove the old mounts. Real bad ones will come out in 2 pieces.

Note: when installing rear mounts, I suggest you install both together; drop the studs into the crossmember, installing the spacer where required, lower the tranny to slightly above its rest position, then start the capscrews that hold the mounts to the bellhousing, and get them in a few turns, then put nuts on the mount lower studs, and spin them on a few turns. The you can gradually lower the tranny the rest of the way, and tighten the fasteners as you go. Once the tranny weight is fully borne by the mounts, you can torque the bolts up good. The reason for this procedure is as follows: with the mounts bolted tight to the bellhousing, the lower studs project out and down at about a 45 angle. The span between their tips will exceed the span between the holes provided for them in the crossmember, and you will be stuck. By installing them in a "gradual" fashion, you get around the geometry bottleneck, and also ensure that the mounts aren't installed with some built-in stress that will hasten their failure.

With the rear mounts done, a similar procedure will work on the front mounts. Be careful not to jack the motor so high that the distributor get damaged by interfering with the firewall. Sometimes, I've had to cut a little excess length off the front mount studs to enable myself to winkle 'em in.

Hope this helps.



Gord Richmond, within Weasel range of the Alberta Badlands

showbizkid
07-16-2006, 12:09 PM
That's awesome! Thanks!

---------------------------
Clark in San Diego:

Proud new owner of a '63 Lark!

Milaca
07-16-2006, 11:36 PM
I looked at the tranny mounts, and they appear to be dry and in good shape. Perhaps they were replaced at some time? Anyway, i adjusted the linkage down by the tranny, and now i have no more buzzing noise and the car shifts like a new car! Thanks Gord!

casey
07-17-2006, 04:30 PM
Milaca- the previous posts on the pressure regulator valve in the tranny are correct. The procedure for adjusting this is in the shop manual. I would urge you to buy one. They are in reproduction and you'll see them all the time on EBay. It's the best thing you could buy for your Daytona.

By the way, I too just purchased a '64 Daytona hardtop. I am beside myself with excitment.