| Author | Message | ||
     Francois Charlier Yet to post message Username: vonplum Post Number: 1 Registered: 3-2011 |
Hello, I have a little problem about my gearbox. there is a rough between 2 and 3 when the speed up. Could you help me please Thank you vonplum (I am new on this forum) Sorry for my english, I am french | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 412 Registered: 12-2004 |
Hello Francois, This is unfortunately a fairly common problem which has given the Hydramatic transmission on our cars an undeserved bad name. In most cases it has been caused by those not in the know (or the lazy), not checking the carburettor/transmission linkage after tuning the engine up as it can alter the gear change if the engine timing or engine idle speed has been re-tuned. It can also mean that the transmission hasn’t been serviced for quite some time. The first thing you can do is look for the simplest solution. Take the car for a short drive and look at the speedometer and take note at what speed the car is doing when it goes into top gear (during gentle acceleration), it should select top gear at around 20 mph (about 32 kph). If it changes into top gear at a higher speed (say 25-30 mph), it is usually a sign that the Control Linkage is out of adjustment. On the Control Linkage (under the car) that connects between the carburettors and the transmission, check to see if the linkage has been straightened; it should be slightly bent. If it is straight, you may need to bend it slightly and take the car for another drive to see if it has improved the gear change ( a certain amount of trial and error will be involved here). If it is indeed bent, then you can adjust the length of the linkage by loosening the nuts on each end of it (again, a certain amount of trial and error by performing small adjustments and driving). If, after you have adjusted this linkage, you find that there is no more adjustment to be made, you can also adjust the top part of the Control Linkage where it connects to the carburettor linkages under the bonnet (Don’t tighten the screw down at the top of it though as you might find that your accelerator will stick on high speed, which can be a little embarrassing – if not dangerous). In most cases, this should fix your problem. If it doesn’t, you will probably need to take it to a transmission centre for adjustment and service (make certain the mechanics are familiar with Hydramatic Transmissions). Another cause could be that, in the past, the transmission was rebuilt using incorrect clutches from General Motors’ cars (such as the Cadillac). Their clutches are flat and are not suitable for R-R and B transmissions. Our ones use a ‘wavy’ clutch plate and if you have a bit of a search through the Technical Forum, you will find that Richard Treacy has put some excellent posts concerning this subject. In the meantime, look for the control linkage and fault diagnosis sections in the Technical Section link below: http://rrtechnical.info/autotransmissions/tsd2042.htm Hope the above fixes your problem | ||
| John Shostrom Prolific User Username: silvawraith2 Post Number: 121 Registered: 4-2005 |
Well done, Robert! Your advice is an excellent example of why this Forum is so valuable. Top marks. Cheers John | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 413 Registered: 12-2004 |
Hi John, Nice to hear from you again. I hope it helps Francois with his problem. Francois, please tell me how you fared. | ||
| Francois Charlier New User Username: vonplum Post Number: 2 Registered: 3-2011 |
Hi Robert, You are right the car remaided 2 years. more I drive , less is the rough but I Will follow your checklist friday and i will tell you if it is better. thank you very much for your help. françois | ||
| Francois Charlier New User Username: vonplum Post Number: 3 Registered: 3-2011 |
Hello, One more question my problem is only between 2 and 3 all other change is good. if I change the adjustment of linkage what is happening about the other change? françois | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1303 Registered: 4-2003 |
Francois / Peux je suggère que vous regardez l'homme de l'atelier pour votre voiture dans notre bibliothèque technique. Base diagnostic tests et la faute est couverte de http://rrtechnical.info/autotransmissions/tsd2042.htm. Lorsque vous avez les données à partir de ces nous pouvons avoir des discussions plus spécifiques. | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 414 Registered: 12-2004 |
Hello Francois, I’m not quite sure what Bill’s remarks are as I’m not conversant with the French language. If the transmission was restored 2 years back, then I suspect that either the wrong flat discs were installed or the transmission was incorrectly adjusted (hopefully the latter). The adjustment won’t affect the gear changes in any other gears as the jolt between 2 and 3 seems to always be the change up that is the culprit. Wishing you success, Robert | ||
| Francois Charlier New User Username: vonplum Post Number: 4 Registered: 3-2011 |
Sorry I mean my car was stationnary since 2 years. the engine is refit but my gearbox is not refit (it is an original ) my kickdown is no perfect too and I believe that Robert Wort are on the correct diagnosis. I will check the linkage and i will say you the result. It is a great website and a good forum Thank for your help francois | ||
| Francois Charlier New User Username: vonplum Post Number: 5 Registered: 3-2011 |
Thank you Robert Wort for your help. My gearbox is good, no perfect but really acceptable . no perceptible 1 to 2, good but perceptible 2 to 3 , no perceptible 3 to 4 Tomorrow I will set the Kick down. With kind regards francois | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 415 Registered: 12-2004 |
Well, that’s excellent news François, You might find that tuning the engine may improve it even further. The Hydramatic will never be quite as smooth as the later GM 400’s but I must admit that I rather like the ‘mechanical feel’ of the Hydramatics when they are functioning as they should. Thank you for telling us all how you went as well. It can be quite frustrating when someone gives advice and never finds out how the advice was used. It happens all the time to Bill Coburn and Richard Treacy and they have been of enormous help to many a forum member. If you haven’t already done so, have a read through Bill Coburn’s Tee One Topics http://rrtechnical.info/TeeOne/teeone.htm You will find them informative, educational and very entertaining. Bill has managed to eradicate the boredom out of technical publications with his wit. You might say that he is the ‘Charles Dickens’ of the motoring fraternity.  Good luck with the kick-down Cheers Rob | ||
| Francois Charlier New User Username: vonplum Post Number: 6 Registered: 3-2011 |
some news about my gearbox, now it is perfect, the kick down is set . After your checklist all it i goog thank you very much françois | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 416 Registered: 12-2004 |
That’s great news François, Perhaps some other Silver Cloud/S series owners can take a leaf out of your book and get their transmissions working as they should. Rob |
