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Hi folks,

After getting everything back together, and doing the Ultramatic throttle adjustment as best as I can (not having the special tool, I just measured 2.75" using a square, and did the best I could down below, not much room to operate down there around the lever), I note that when warm the Ultramatic direct-drive clutch doesn't like to "kick down" when I smash the throttle. I can get it to disengage at stop, and it seems to engage allright when accelerating from a stop, but it might overall be engaging a little early and disengaging a little late upon deceleration. I was wondering whether there was any fine adjustment I might try.

Thanks in advance...

You didn't mention the speed you were going when trying to kickdown but the original Ultras will not drop out of direct drive in the normal kickdown sense if the car is moving above 50 mph. Note that the owners manual says 50 but in actuality the kickdown can sometimes be locked out even if doing a bit less than 50.

Here is a bit from the 53 owners manual.

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I'm talking about slow speeds, slowing down to take a right turn, then accelerating out of it, or going straight on a city street that starts to head uphill, and trying to accelerate, in both cases it seems the Ultra is a bit hesitant to kick down, so I end up lugging the engine some.

This sounds more like a Ross special question so if he doesn't see your post maybe a PM would get a good suggestion or two as to what to do next.

Have you checked the governor and throttle pressures? In reading this bit from the training manual on how the direct drive valve and kickdown works, it sounds as if one of the pressures might be out of spec. Maybe due to adjustment or maybe due to a worn bushing allowing a pressure to be lost so it cannot do what is needed.

I think at the least I would verify the thottle pressure because if that pressure is low several things can be seriously affected. The caveat is the test point is an internal port directly on the valve body and I don't know if a hose fitting can be attached without the extended depth test fixture and pan. Another question for Ross.

Aside from the DD application, among the other very important functions of throttle pressure is to act on a valve which determines how much clamping pressure is applied to the high range clutch discs. More speed and torque from the engine means more pressure is needed to clamp the discs together. Too little pressure and they will slide against one another and burn.

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I'm interested in the answer to this as well. My car does the same at slow speeds. Say I slow from 45 down to 15 or 20 and have to accelerate again (stoplight turned green before I got to it)...the transmission doesn't always kick down and the engine really lugs until it gets up to speed again.

I remember reading somewhere that the direct drive kicks off once the car hits 11mph, and goes back into torque converter. Am I making stuff up here?

-Kevin

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You are correct. The governor pressure is supposed to be low enough at that speed the DD can release. There is a service article on checking the governor for reasons DD clutch disengagement might be delayed. Packard found if DD released much below that speed the engine was prone to stalling when the car was coming to a stop.

Thankfully mine kicks down when I hit 11mph. But between that and say 25 it doesn't kick down when I push on the gas again. I'm not slamming the gas though....just normal pressure.

-Kevin

Mine kicks down around 50 going up a hill. Don't like it cause it should stay in. Im not trying to kick it down. I give it more gas then it kicks down.

The flip side. The d d. Can't slip..

Other ultras never kicked down .

My throttle pressure is open. And so is that 56 Caribbean. It doesn't down shift up a hill.

Peter fitch said he leaves 5 or 6 threads showing is how he does it.

Yap... Ross what's our problem...

Well, it is nice to have a fan club.....


51-54 regular Ultras first:

* make sure the throttle linkage bracket on the firewall has not collapsed back toward the firewall. If it has space it out by wedging an old shock bushing behind it.

* make sure the spring link in the pull rod to the carb has not frozen. That fat part is spring loaded to allow the throttle linkage to overtravel to effect kickdown. It should extend 5/8 inch or so if you pull on both ends of the rod briskly.

*Make sure that your gas pedal has full travel. With the engine in low idle position, examine the vertical rod that goes down to the gas pedal mechanism. Adjust its length til the pedal mechanism lever it is attached to is about as far down as it can go without jamming,

*Still no joy? Then climb under the car with a right angle straight blade screwdriver and a 7/16 wrench. Loosen the clamp screw that holds the throttle lever to the right rear of the trans. Use your screwdriver to rotate the shaft a little bit CW. The is will raise your upshift point and make the kickdown point come sooner.

Be aware that the early Ultras do not kickdown easily and if you just slowly give more gas your not gonna get one. You have to about jab the pedal to the floor like you are kicking down an overdrive.


The Twin Ultramatics are a completely different animal in that regard and are very responsive to what you do with your foot. That is why I really enjoy driving them on our backroads. Riki, if yours is too responsive, move the carburetor link into the top hole, and if that does not help, then move the link a little forward on the carb pull rod.

I just wanted to say thanks! I haven't been able to check anything except the spring link in the rod - that MAY have been frozen, but I pulled on it pretty hard and it is free now, will try to squirt some lubricant in there for the long-term.