Trans Gurus, no up-shift?

[enjoi1968]

D1, new to me Hp22 mileage unknown

Did a trans swap a bit ago, finally got time to get finishing touches done and take it out for a test drive. Hard shift into reverse, meh nothing worse then my HP22 before. Drive, 3, 2, 1 all move forward. Ok let's get it to go through the sequence, or not.

Currently I can drive Forward in any of my forward motion gears, or reverse in R. But will not up shift.

Thought it could be the kickdown cable being too tight, unhooked that and gave it a yank, it wasn't even engaged. still wouldn't up-shift. Fluid is right on the money while idling cold in neutral, DEXIII full.

I'm leaning towards it almost has to be internal since these are hydraulic run units, should not be an electronic issue.

With everything torqued to spec I'm sort of wondering if that is the answer.

 

[Ian Ashcroft]

Hi two possible causes
The 'forced kick down plunger' is stuck in its full stroke position, usually caused by pulling the kick down (control) cable past (beyond) its full stroke. As a matter of interest how do you figure the kick down is disconnected?. Do not run with the cable dis-connected as it controls the clutch pressure, cable dis-connected equals min pressure on clutches equals clutch slip and burn out. It is sometimes possible to release the plunger , remove the sump, locate the kickdown cam, follow the kick down plunger back, it acts on the forced kick down plunger via a spring, you can see the plungers move looking in the vent slots. Just tap the valve body lightly by the plunger if it is not moving.

The second most likely is a stuck governor valve, the box does not shift up when cold. This is caused by excess of 'sludge' in the gov body, only cure is to remove the gov strip it down to component parts and clean.

If you are not sure talk to your local auto box shop.

Regards Ian Ashcroft

 

[enjoi1968]

Thanks Ian, You guys at Ashcroft rock.

I am by no means a trans mechanic and have been enlisting help from my local yokal trans guy, he doesn't like the design of the hp22 from the get-go so he's been not the most enthusiastic.

in reference to the kickdown cable, at the throttle body I disconnected the cable from the throttle body so that it would not force a a gear to drop when all I was looking for was an upshift.

When I disconnected the end of the kickdown cable at the throttle body I gave it a slight tug to see if it had been fully engaged, I felt it click and engage as if someone was slamming the skinny pedal. so my assumption was that it had not been running while the cable was too taunt and therefore in constant "kickdown" mode. I did not disconnect the cable internally in the trans, just externally.

I did drain the all the ATF out of the sump and there was a small amount of grit/sandish looking soot in the atf, I wonder if it's been sludged.

I think going internal is a little out of my range of skills, so if I must go internal I'll more then likely be looking at a another unit.

 

[Ian Ashcroft]

Hi the kickdown on the ZF occurs in two ways, part throttle kickdown is when the gov overcomes the throttle setting pressure, full or forced kickdown occurs when the cable is fully extended, if you pull the cable it will travel quite freely untill you reach the forced kickdown, this is a step on the cam so requires quite a firm pull to overcome it.

From what you have now described, ie sludge, I would bet on a stuck gov. This is a relatively easy task , just requires care, cleanliness and some tools.

If you want to try for yourself I can go through the step by step process, worst case is you will need to eat humble pie and take the bits to the auto box shop.

Regards Ian Ashcroft

 

[singingcamel]

Since were on a tranny thread ,( sorry for the hi jack) and we have a expert's attention.
My d1 , rolls back when in park , come to think about it my daughters d1 does too.
I'm thinking a cable issue but may be wrong , any help would be appreciated..

 

[enjoi1968]

D'oh! I forgot, yes, my trans as well does not "park" i.e. I can put it in park and without setting the ebrake watch it roll away!

I believe the parking pawl is in the rearmost part of the trans itself though I'll let Ian chime in with better info.

I am up in the air as to whether I am going to attempt a repair on this unit myself or swap for another known working unit. My only issues is that if I fubar this one up fixing it I won't have any ground to stand on for an exchange with another unit.

 

[flyfisher11]

FWIW I recently had to get into my RRC's tranny and fix the governor valve assembly. I spoke with Dave Ashcroft and told him my situation and he pointed right to the culprit. In my case the truck was taking off in second unless I pulled the shifter down manually. Once warmed up it would not go in reverse. Luckily I had a spare tranny from Willy T. We pulled the governor valve out of it and inspected it. It appeared in good shape. We then pulled the BW tcase, the rear output shaft and finally the rear plate of the tranny. Once there it was easy to pull the governor valve assembly out. There is a counter weight (I think that is what it is called) on the side of the g-valve. It was stuck and not spinning freely. Then once we pulled the valve assembly off the splines one of the three O rings was broken. It was still on the shaft but split. Where it was split on the inside of the governor valve there was scoring. Dave told me to look for that. We put new O rings (specialized as they are flat O rings) and transplanted the good governor valve on from the spare tranny, reassembled and hot damn she is working like a charm!

The Ashcroft family rocks for sure! Dave even gave me the part numbers for the O rings and company here in the States where to get them.

 

[Ian Ashcroft]

Hi Lets try the simple fix first to check if the problem is associated with cable (linkage) or in the box.

Have a good root arround to see if anything has come loose on/in the shifter assembly resulting in loss of movement of the shifter cable.

A common fault particularly on V8 is caused by heat from the exhaust. The cable sometimes bowes when hot result in loss of movement, chock the wheels so the car cannot move. Crawl under and have someone move the shifter D to Park and back a few times watch for the cable bowing away from the auto. If it does the add a 'P' clip at the end of the cable outer, there are 2off 6mm tapped holes in the autobox side to accomodate this clip.

If the above is not the fault then dis-connect the barrel nipple at the gearbox end of the shift cable (pull the split pin) now move the lever to the park position. Does it lock??. if it does then you have an adjustment problem. Put the gearbox lever into D and the shifter into D to adjust the barrel nut so it fits the lever.

Always chock the wheel before venturing under the car!!

Hope this helps

Ian Ashcroft

 

[singingcamel]

Hey , thanks alot. I'll have a peek to see what going on. Unfortunately my shop bays are full and I'm going tp have to wait till the weather passes.
Forcast calling for freezing rain turning to snow with a chance of 6 - 10 "'.
I appreciate the response Ian ..
www.singingcamel.com

Sorry, where would one get this P clip?

 

[mbrummal]

Sorry, where would one get this P clip?

its one of these. nothing special.
http://www.moto-racing.co.uk/ccp51/media/images/product_category/HEL P Clip.jpg

 

[Ian Ashcroft]

Hi the 'P' clip is just a generic term for a small pipe/tube support in the form of a 'P'. Available in the UK from pneumatic/plumbing/electrical outlets.
I forgot the weather out there, I am semi retired in Spain, hence the split posting from Dave and myself, weather here is good!! 20deg C.

Regards Ian Ashcroft