Topklasse Discussion Board  
Home Forum Legal/Privacy Media/Picture Gallery Websites and Links Technical

Go Back   Topklasse Discussion Board > THE CRAFTSMAN - TECHNICAL DEPARTMENT > MECHANICALS

MECHANICALS With a 30 year-old automobile, there will always be discussion here - maintenance, modifications and mechanicals.

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 30th November 2014, 02:31 PM
sean sherry sean sherry is offline
Aristocrat
 
Join Date: Jan 2012
Location: sydney
Posts: 1,562
Smile For budding Automatic Trans mechanics

Goggle Sonnax Zip Kits . Repair Kits for worn Valve Bodies.... Valve bodies are wearing out as a result of the modern solenoid control of the Duty Cycle of the sliding valves. In and out like a fiddlers elbow as we drive along.
Plus there is a range of internal parts for Mercedes Torque Converters and some Transmission Parts. Where were all these goodies when I had a Transmission Shop ?
Back in the olden days as my Grand Children would say.
Reply With Quote
  #2  
Old 30th November 2014, 07:37 PM
Michel's Avatar
Michel Michel is offline
The Prince of Arabia
 
Join Date: Feb 2008
Location: Sydney, Australia
Posts: 9,165
Default Re: For budding Automatic Trans mechanics

Quote:
Originally Posted by sean sherry View Post
Goggle Sonnax Zip Kits . Repair Kits for worn Valve Bodies.... Valve bodies are wearing out as a result of the modern solenoid control of the Duty Cycle of the sliding valves. In and out like a fiddlers elbow as we drive along.
Plus there is a range of internal parts for Mercedes Torque Converters and some Transmission Parts. Where were all these goodies when I had a Transmission Shop ?
Back in the olden days as my Grand Children would say.
Sean,

I can't even keep up with you....
I wish I could understand what you are talking about
(I know, I know... trannies)
__________________
Michel

1978 W116 690SEL # 3312
1985 R107 500SL AMG
2000 C208 CLK430
Reply With Quote
  #3  
Old 1st December 2014, 07:39 AM
sean sherry sean sherry is offline
Aristocrat
 
Join Date: Jan 2012
Location: sydney
Posts: 1,562
Smile Re: For budding Automatic Trans mechanics

As we all also have modern cars and knowledge is power ....
When a Transmission re build comes along and we are hit with a bill for several thousand dollars just for a Valve Body alone, it would be nice to remind the Repairer that the " Valve Body" can be successfully repaired for a fraction of the cost.

For Michael....The Valve Body is the Brain of the outfit, controls everything via sliding Valves. Valves are steel and the body is alloy. The body wears and the oil pressure leaks .

A bit like Lucas electrics when the smoke escapes !
Reply With Quote
  #4  
Old 8th December 2014, 06:22 AM
daantjie daantjie is offline
Respectable
 
Join Date: Sep 2014
Location: Vancouver, Canada
Posts: 27
Default Re: For budding Automatic Trans mechanics

Hi Sean

I am currently struggling with my 6.9 transmission, giving me fits! Lots of flaring under anything put soft throttle, and shifts are very soft.

I replaced the modulator and cranked up the pressure but no dice.

This started after I had the rad recored. Do you think some grime is making the valve body stick somehow? Or can the modulator valve inside the trans be stuck, and not getting hit by the thrust pin?

Cheers
Daniel
Reply With Quote
  #5  
Old 8th December 2014, 07:08 PM
Styria's Avatar
Styria Styria is offline
The Godfather
 
Join Date: Feb 2008
Location: Sydney
Posts: 8,622
Default Re: For budding Automatic Trans mechanics

Hi Daniel, welcome to Topklasse. I have seen your name on the 116.org site, but as I am not a member of that site, I have not been able to respond to you. I do read some of the posts, but I can't really take a lot of notice. Now, to your problem. Sean of course, is much more of an expert than what I am, but I'll tell you what I know.

Flaring can of course be adjusted - as a rule by the modulator valve. If you are unable to effect any improvement, you will need to look elsewhere. Firstly, did your problems start after you had the radiator flushed/serviced/recored ? If your transmission worked well prior to the radiator work but is troublesome now, you will need to go a little deeper into rectifying or addressing the issue. Firstly, you will need to turn your engine until the torque converter's drain plug (an Allen key fitting) is visible from underneath. In order to turn the engine, I would suggest that you remove all spark plugs. Then, from underneath, with a heavy duty screwdriver or similar instrument, you will need to turn the converter until the drain plug is visible. Remove, and collect all oil in a container - probably abut three to four litres.

Next, you will need to drop the transmission pan (secured by four bolts), and then remove the valve body secured, from memory, by about eleven bolts. Make sure that you remove those bolts, and not the others that hold the various layers of valve body together - obviously, the filter element needs to be removed first before you can get at those bolts. Just bear in mind that you are now getting to the professional auto trans shop stage. At home just okay, but not a nice job. With the removal of those bolts - always leave a couple in place that will hold the valve body up. As well, you need to be prepared for copious quantities of oil that will continually drip down. Also, the transmission lever needs to be in the park position to enable the internal selector rod to be withdrawn together with the valve body.

Once the valve body is out, do not dismantle it. Just wash it out thoroughly in a bath of petrol and use compressed air to blow it out as best as possible. Replacement of the valve body (refitting thereof) is not a job for the home mechanic - again, it can be done, but you really need to know what you're doing. Once you've got everything back together and your problem persists, it will be time to remove the box from the car, dismantle and replace clutch packs. Unless you know what you are doing, the transmission shop once again is the place to go. Many years ago, when I first bought Gleaming Beauty, I had flaring from second to top. I was able to eliminate the flaring by adjusting the modulator valve, but that then rendered the shift from first to second too harsh. Removal and rebuilding the box became a necessity - on dismantling I found that all clutch seals were like Bakelite - useless in other words. Adjustment of bands - no adjustment for Bands 2 and 1, but 3 is adjustable. It primarily deals with reverse operation. Again, a fairly awkward job and you need to know the clearance of free play of the servo unit shaft.

Hope that helps - maybe not what you want to hear, but let us know how you get on. Regards Styria

Last edited by Styria; 8th December 2014 at 07:10 PM.
Reply With Quote
  #6  
Old 9th December 2014, 02:30 AM
daantjie daantjie is offline
Respectable
 
Join Date: Sep 2014
Location: Vancouver, Canada
Posts: 27
Default Re: For budding Automatic Trans mechanics

Hi Styria

Thanks for you reply and great tips.
Yes , I fear I have gone into panic mode and posed on so many forums now in desperation, that I am being bombarded with so many tips it is getting a bit overwhelming

I think my current level of skill is limited to dropping the pan and changing fluid. Also I have no real work space at my current house, so any kind of "deep dive" work is pretty much impossible.

As such I am prone to leaving the valve body and dropping the trans to the experts, I can just see real heart ache if I attempt to fool around with the valve body

Last night I pulled the check valve which connects the bypass line off of the aux trans pump to the case, and I found that there is no spring or ball inside the valve. Surely this can't be good??? The previous owner had some trans work done before, so I can only guess whoever worked on it either neglegted to put these back or dropped them when they fitted the trans back, or they somehow tried doing a bypass of sorts to try and "fix" another problem.

Any ideas on that?

Cheers and thanks!
Reply With Quote
  #7  
Old 9th December 2014, 08:50 AM
sean sherry sean sherry is offline
Aristocrat
 
Join Date: Jan 2012
Location: sydney
Posts: 1,562
Question Re: For budding Automatic Trans mechanics

Sounds to me like a Line pressure problem. The very first step is to " hook up a pressure gauge. " The idle pressure in neutral will show if the pressure regulator is doing its job. If it is low then that's your problem , either dirt or a broken spring. If normal check pressure in D and with foot on brake rev the engine , ditto in R. Pressure should rise as the vacuum drops . Best way is to use a vacuum pump to the modulator. even at idle the pump should respond to the changing modulator input.
Without a pressure gauge you are playing guessey games .

As all shifts are affected my money would be on the pressure regulator , bearing in mind that it was operating ok before .
Let me know how the pressures are
Sean
Reply With Quote
  #8  
Old 9th December 2014, 09:09 AM
sean sherry sean sherry is offline
Aristocrat
 
Join Date: Jan 2012
Location: sydney
Posts: 1,562
Smile Re: For budding Automatic Trans mechanics

P.S. The modulator valve operation is easily checked by varying the vacuum up and down with the pump .....Pressure rise and fall should be nice and smooth .. no jumps or hesitations. Start with a cold engine and progress to warm/hot... just to be sure.
There is no need to dismantle anything until the cause has been identified .

As a generalisation for most Auto Boxes, hard internal seals will show up with a cold engine ,they tend to soften up with heat if they are not to far gone. Slow engagement of D or R and also some flaring issues.
Reply With Quote
  #9  
Old 10th December 2014, 03:48 AM
daantjie daantjie is offline
Respectable
 
Join Date: Sep 2014
Location: Vancouver, Canada
Posts: 27
Default Re: For budding Automatic Trans mechanics

Thanks very much for all the advice, Sean and all.

I will have to go shop for a pressure gauge for sure, seems like this is the only way to do proper diagnosis on these bad boys

Cheers
Daniel
Reply With Quote
  #10  
Old 13th December 2014, 12:32 AM
s class's Avatar
s class s class is offline
Connoisseur
 
Join Date: Apr 2008
Location: South Africa
Posts: 790
Default Re: For budding Automatic Trans mechanics

I'm busy with a 350 trans at the moment, will start another thread on it.
__________________
'80 W116 280SE euro - the ride
'76 W116 6.9 euro - trusty rusty
'78 W116 6.9 euro - the AMG
'74 W116 350SE euro - the stand-in ride
'82 W126 500SEL euro - full hydraulics - the limo
'83 FORD XR3 - the beast

0 benzes on stands, 5 RUNNING
Reply With Quote
  #11  
Old 13th December 2014, 06:34 PM
Styria's Avatar
Styria Styria is offline
The Godfather
 
Join Date: Feb 2008
Location: Sydney
Posts: 8,622
Default Re: For budding Automatic Trans mechanics

Quote:
Originally Posted by s class View Post
I'm busy with a 350 trans at the moment, will start another thread on it.
Hi S Class, welcome back. TK is the place to make yourself comfortable in. Lots of friendly faces Regards Styria
Reply With Quote
  #12  
Old 17th February 2015, 07:38 AM
daantjie daantjie is offline
Respectable
 
Join Date: Sep 2014
Location: Vancouver, Canada
Posts: 27
Default Re: For budding Automatic Trans mechanics

Hi guys

Guys, just to close the loop on this one, happy to report that I have managed to get my trans issue sorted (I hope permanently)
With lots of help from various sources, talking me off the ledge and such, I managed to pull the valve body and take a good hard look at it.
Seems as if the control pressure valve was binding in the bore a bit. After some careful honing by hand, I got the sleeve to move again in the bore.
Also cranked up the modulator nice and high, so now I am getting that nice and tight, firm MB shift again! How I do like tight and firm
As well I had another good look at all linkages. Micro adjustments here does indeed make a big difference!
Thanks to all for the tips.
Honourable mention to Frank Reiner in California, he is a member on another forum, very knowledgeable and he helped me a lot!

Cheers
Reply With Quote
  #13  
Old 19th February 2015, 07:15 AM
Michel's Avatar
Michel Michel is offline
The Prince of Arabia
 
Join Date: Feb 2008
Location: Sydney, Australia
Posts: 9,165
Default Re: For budding Automatic Trans mechanics

Good to know it all ended well!
__________________
Michel

1978 W116 690SEL # 3312
1985 R107 500SL AMG
2000 C208 CLK430
Reply With Quote
  #14  
Old 4th March 2015, 04:49 PM
sean sherry sean sherry is offline
Aristocrat
 
Join Date: Jan 2012
Location: sydney
Posts: 1,562
Exclamation Re: For budding Automatic Trans mechanics

Just been re reading this thread again , plus some others on problems with Auto Boxes . It never ceases to amaze me that lots of Workshops , not just Home Mechanics tackle Transmissions with out a Pressure Gauge ie. play guessey games, ( no diagnosis ) then hand their Customers the Bill. Strip the Box and can see nothing broken only to eventually find that the problem was in the Valve Body all along ( maybe a couple of weeks later ) Todays lot... nothing much has changed .. replace parts until the problem goes away.

Call me a cynic.. my Wife does.
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
560SEL Trans & Diff Oversize MERCEDES W126 32 3rd July 2015 10:06 AM
Weight of a 6.9 engine & trans Oversize MECHANICALS 26 18th June 2015 10:03 PM
Automatic Transmission Manual Part 1 WGB TECHNICAL INFORMATION 1 8th June 2011 07:14 AM
Automatic oil leak WGB MECHANICALS 4 4th March 2008 07:33 PM


All times are GMT +10. The time now is 02:16 AM.


Powered by vBulletin® Version 3.8.10
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Copyright Topklasse 2020