Jump to content

57 Dynaflow issues...


Guest ozzytom
 Share

Recommended Posts

Guest ozzytom

I had an issue with Lo gear not engaging, and hoped it was going to be a simple fix.

Maybe the Lo accumulator seal or servo piston seal. Sounded feasible as car was driving with no issues in Drive or Reverse. The car would simply not move when Lo was selected.

Anyway, Dynaflow is in the workshop now fully dis-assembled.

Cause of Lo gear slippage was worn Lo band so that needs relining.

The reverse band although looking exceptionaly good, has a score mark around the inner circumference.

Must have had a some grit caught up between drum and band. The drum has a light score mark, but will clean up OK. Is the reverse band OK to use, or should I replace it.

post-72972-143142659175_thumb.jpg

Further inspection found slight wear in the High Clutch piston inner surface. There is a very slight lip created from wear. This is the component which slides on the clutch drum boss to compress the clutch pack together, to lock it for direct drive.

post-72972-143142659181_thumb.jpg

What would be the solution given that a brand new replacement may not be possible?

Anyone have any idea if the wear is significant enough to cause an issue.

I had no problems with slippage in direct drive.

What the maximum ID tolerance. I could have it bored/honed to remove the wear mark but don't have any specs to work with to know the limit to maintain sealing on clutch boss. Anyone have any specs for this?

The other component showing a bit of play was the torque ball bronze bush.

Once again, anyone have any specs on what is the acceptable clearance.

post-72972-14314265927_thumb.jpg

Where can I find a replacement if it is out of spec?

Any help with leads to parts and specs for components is greatly appreciated.

PS.. Looking at the Lo Band compared to the Reverse band, the gap between the mounting tabs is significantly different. Is this an indication that the spring tension of the Lo band has diminished, and might have caused premature wear because it dragged the lining on the drum even when not engaged?

Or will it open up once a new lining is installed?

tom

post-72972-143142659141_thumb.jpg

Edited by ozzytom (see edit history)
Link to comment
Share on other sites

Google Antique Automatic transmission parts and talk to Dave Edwards. Very knowledgeable, helpful and has all the parts at a fair price. FATSCO also has all the parts you may need. If it were me I would replace both bands since it is apart along with the clutch pack. Talk to Dave for the straight scoop............Bob

Link to comment
Share on other sites

Guest Rob McDonald

Dave Edwards' company is Autotran, email info@autotran.us, and he's located near Boston MA. Highly recommended. I'm impressed by how easily you discuss the inner workings of your Dynaflow. I wish I had your confidence.

Link to comment
Share on other sites

Guest ozzytom

Thanks for the leads and feedback.

I sent Dave an email but haven't received a reply.

Found an alternate source who provided great service. Thanks George ( Classic Transmission Solutions )

New lo and reverse band and complete master overhaul kit on its way.

Hope to get the Buick on the road for the Buick Nationals tour party driving through my state in a couple of weeks. :)

Link to comment
Share on other sites

Guest ozzytom

Parts arrived today. Only 7 days from order placement in Springfield, Oregon USA to Adelaide, Australia.

Approx 8000 miles. Very happy. Thank you George and thank you USPS. :)

Now it just needs to be put together.

Link to comment
Share on other sites

Guest ozzytom

Yes Stuart.

As long as the car is up and running in time I plan to come up to Tanunda on the 27th for the run to Birdwood.

Can't make the trip to Perth, but will be good to catch up with some fellow Buick owners.

Wow! 30 cars crossing the Nullabor :eek:

That would be a 10000 km round trip for the Brisbane entry!!! Wow.

Link to comment
Share on other sites

Yes Stuart.

As long as the car is up and running in time I plan to come up to Tanunda on the 27th for the run to Birdwood.

Can't make the trip to Perth, but will be good to catch up with some fellow Buick owners.

Wow! 30 cars crossing the Nullabor :eek:

That would be a 10000 km round trip for the Brisbane entry!!! Wow.

At last count I think 9 of the cars are travelling by road from Queensland and includes a 1930 Tourer, 1930 Roadster, 1934 Sedan and somehow a 1941 Caddy has snuck in there. The rest are from NSW, Victoria and Tasmania.

A few of them ( at least the 1930 Buicks ) are heading back to SA after the Nationals to take part in your Bay to Birdwood run.

In case any of our American friends wonder what we are talking about this explains the Nullarbor Plain!

http://en.wikipedia.org/wiki/Nullarbor_Plain

Link to comment
Share on other sites

Wow thats impressive drive in a 1930's vehicle as some modern vehicles would have trouble doing drive !!!!!!!!

Matt

Drove back from the last Buick Nationals ( Tassy 2012 ) in the 1950 Super Jetback. Melbourne to Perth, 4 1/2 days and about $880 worth of fuel. Great drive and the 1950 Super just ate up the highway. Get some real strange looks when a big maroon car with a toothy grin pulls out and passes the modern stuff!!

If you have a close look at the speedo in the photo with my mate driving you can see what is a comfortable cruising speed.

post-31244-143142687017_thumb.jpg

post-31244-143142687021_thumb.jpg

post-31244-143142687024_thumb.jpg

Edited by 50jetback (see edit history)
Link to comment
Share on other sites

That is some great photos of your journey and I bet that you would have passed a few people with that look:confused: (WHAT the $%#@ was that) It will also give the good folk on this forum a understanding of the NULLABOR plain ... Bit like the old ROUTE 66 out between Barstow and NewBerry Springs Ca.... I had a ride in a friends 59 invicta the other day and we got similar looks:confused: going up the freeway!!!!

I just wished our 57 would have been here by now but its a few weeks out yet !!!!!!! :mad: Would have loved to take it to the Birdwood run and meet a few other Buick owners !!!

Matt

Link to comment
Share on other sites

Guest ozzytom

Well I picked up the Buick this afternoon.

Dynaflow is up and running again.

Had a few other items repaired whilst the car was up on the hoist.... Found a weep at the rear right axle so the bearing and seal were replaced. Also replaced the steering idler mount to eliminate some excessive play. Took it for a test drive tonight. Steering is as good as new. No slop at all. Even with the power assist, it now feels much tighter.

Trans works well although I feel the transition from Lo to Drive is too abrupt. It shifts with a very solid thunk!

almost feels like it has an aggressive shift kit fitted. I'll get a few hundred miles on the trans and then reassess the situation.

looking forward to catching up with all the Buick owners on Wednesday.

Does anyone know departure time from Tanunda and route to be taken and ETA at Birdwood?

Link to comment
Share on other sites

Not to265951d1408662539-57-dynaflow-issues-101_6135-800x600-.jpg hijack this thread, but I see a few other things in this photo that raise some questions:

Your mate is wearing a long sleeve shirt, and the drivers window is open a small amount. But the picture shows a desert foliage scene. What is the temperature on this stretch of road? And is that the same you'd expect to find on the Nullabor

Link to comment
Share on other sites

looking forward to catching up with all the Buick owners on Wednesday.

Does anyone know departure time from Tanunda and route to be taken and ETA at Birdwood?

Tom,

Try ringing Alan Haime, he is staying at the Weintel Motel in Tanunda. Phone number is 85632303. Alan is running the SA leg and will have the info you want. I know they wanted to catch up with SA Buick owners and are looking for someone to start a local club.

Link to comment
Share on other sites

Guest ozzytom

Hello John.

The temperature in our deserts in Oz vary greatly.

Extreme heat in summer months can reach 50 deg Celscius (122degF) but if there is no cloud cover to retain heat the temperature drops dramatically during the night. Typical minimum temps in summer drop to about 15 degC. (59 degF)

At this time of the year it is still quite cool across the Nullabor, as it is close to the Southern Ocean.

Mean temperature range is 6~20 degC, but the record low for August is -5 degC ! (23degF) .

Link to comment
Share on other sites

Guest ozzytom

Thanks Stuart,

I assume Alan will be arriving at Weintal on the 26th?

I'll leave a message for him with the desk.

regards

Tom

Link to comment
Share on other sites

Guest ozzytom

Getting back on topic,

I am trying to ascertain whether the shift from Lo to Drive should be reasonably smooth when Not under acceleration.

The dynaflow has just been rebuilt with new bands and new clutch pack so I am hoping the hard shift to drive is just the clutch plates grabbing tightly as they have not bedded themselves in yet.... Almost no slip when activated.

For those who have had their dynaflow rebuilt, can you advise if you experienced a similar issue.

Will the shift smooth out within a few hundred miles once the plates have had a chance to absorb some lubricant?

Link to comment
Share on other sites

Service manual required: check shift linkage adjustment; check pressures and note especially pressure at high accumulator which 'cushions' the shift; be sure engine and transmission mount are in good shape and especially the thrust pad.

Report back.

Willie

Link to comment
Share on other sites

Getting back on topic,

I am trying to ascertain whether the shift from Lo to Drive should be reasonably smooth when Not under acceleration.

..

Thanks for the info on the temps Tom. Regarding your Dynaflow, using low to start and shifting to drive will almost always be a hard shift. My 56's was rebuilt 30 years ago and it will still shift like that. But with your Dynaflow rebuilt you should be able to just start in Drive and not feel any shifting. Is there some reason you need to start off in low?

Link to comment
Share on other sites

Guest ozzytom

Thanks Willie and John,

Engine mounts are fine and new transmission mount was fitted.

I'll get a few miles driven and see how it goes. When I get it back on the hoist in a couple of weeks I'll check the pressures at both accumulators, both pumps and stator pressure to have some baseline figures to monitor over time.

There's no problem with starting in Drive, and car accelerates smoothly without issues.

It's just that in testing the trans after the rebuild the shift from Lo to Drive is so noticeable compared to before the rebuild. I am just trying to establish what is considered "normal" behaviour.

Prior to the rebuild the shift was quite smooth, as it was obviously slipping a bit when engaged.

Am I right in understanding it is the clutch pack which is engaged when shifting from Lo to Drive to make the direct drive functional... So the solid thunk I am feeling is associated with clutch engagement?

Link to comment
Share on other sites

Thanks Willie and John,

Engine mounts are fine and new transmission mount was fitted.

I'll get a few miles driven and see how it goes. When I get it back on the hoist in a couple of weeks I'll check the pressures at both accumulators, both pumps and stator pressure to have some baseline figures to monitor over time.

There's no problem with starting in Drive, and car accelerates smoothly without issues.

It's just that in testing the trans after the rebuild the shift from Lo to Drive is so noticeable compared to before the rebuild. I am just trying to establish what is considered "normal" behaviour.

Prior to the rebuild the shift was quite smooth, as it was obviously slipping a bit when engaged.

Am I right in understanding it is the clutch pack which is engaged when shifting from Lo to Drive to make the direct drive functional... So the solid thunk I am feeling is associated with clutch engagement?

Smooth means slipping the clutch pack which is engaged when shifting from Lo to Drive. That is the argument for 'shift kits' in step-gear transmissions. All 3 of my dynaflow cars shift differently. Even different transmission fluids will affect shift harshness. Back in the 1960's when driving a 55 'leaker', I was given a case of 24 cans of Type-F fluid and that slowly made for firmer shifts.

Willie

Link to comment
Share on other sites

Guest ozzytom

Good news is that after 200 miles of use, the trans is as smooth as silk now.

The heavy shunt on change from Lo to Drive has gone.

Under light acceleration there is just a firm shift. No shudder like when I first drove it after the rebuild.

Under hard acceleration the shift is smooth. Positive without any flaring or slippage.

Looks like it just needed few miles for the clutch to settle in. icon14.png

Just 1 more item I have....

an intermittent rattle coming from the steering column which stops if I lightly hold the gear select lever.

It's the only rattle noticeable in the cabin that the car has, and it is annoying.

Link to comment
Share on other sites

Guest ozzytom

I should have said this issue was present before the trans came out.....

A diagram of the steering column gear select mechanism would really aid in getting a handle on this rattle.

my 57 Buick chassis service manual has no information regarding the gear select mechanism.

Link to comment
Share on other sites

Ozzy: Good to hear things have worked out. But gotta say, Why are you even using low gear unless you are pulling your house with you and starting at the bottom of a hill ? I have had 5 different 57 Buicks starting with my Dad's in 63 and 4 of my own since then and never recall even having to use low at all. This is very perplexing. Now my 49 Buick Super would start out better using low gear first but those early dynaflows up through 52 were a single unit of inferior torque and output. 1953 they were improved with some tweaks in 55. But now for 1957 thru to 60 these dynaflows go by simple stepping on the gas pedal and very well indeed.

Try just using the gas pedal as you are not saving gas going from low to drive .

Link to comment
Share on other sites

Guest ozzytom

Hello David

The use of Lo gear was simply to ascertain everything is operational after a full rebuild of trans.

I have had a few occasions with a car load of friends and a boot full of picnic gear where starting on an incline has warranted using Lo gear.

But you are correct . Starting in drive provides adequate acceleration under most cases.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...