Thunderchief

Hi, the speedo was damaged by shavings from the casing caused by the roll pin galling on the case. The parts jammed the gear and stripped the teeth. We cleaned the case with large quantity’s of brake cleaner and compressed air. We did the same with all the components. We used the original valvebody and filter.

Thanks to everyone who replied with advice. After a test drive I noticed that it was not actually working in 3rd gear properly and then the speedo stopped working. In the end it was the direct clutch plates that were the main cause, they were completely worn out. Also the governor has a roll pin that holds the drive gear on to the shaft, this had come out and jammed on to the casing stopping the governor from turning. Parts of the casing had then stuck in the speedo drive gear and stripped the teeth. We bought a second hand TH400 that had been rebuilt but not used, as a spares and repairs doner. then we stripped cleaned and rebuilt with the best components from each gear box. the Gear box seems to work fine now. I was able to test at about 60mph and the drive seems good with no slipping. and reverse works now! Thanks again

Yes thanks that is a good idea. we did a bit more work at the weekend. I was going to look at reverse servo, but it doesn't look like it can come off without the valve body being removed. so I will wait until i have the rebuild kit. After trying it again on Sunday it does seem a little better now the oil has been circulating. so I might try to take it for a run to really get it working. It is now road legal. It doesn't look like a wheel problem, when you put in in drive there is a definite shunt in the transmission and the revs drop significantly, when you put it in revers there is only a faint shunt and the revs barely drop at all.

Thanks for the extra pointer guys, for an update today we changed the filter and replaced the oil. this has had no effect When testing the car, it drives in all gears except reverse. L1, L2, and drive are all seemingly fine. When removing the oil pan, there was quite a lot of sludge in the bottom, and the oil was quite dark, nearly black. following the service manual I have, it suggests that it can be caused by the Vacuum controller so we removed this and tested it with a vac pump and it seems to be fine and the valve in the gearbox also seems fine. we have not tested since replacing this however. I will have a bit more time on it tomorrow, not sure if we can remove the valve body without having a replacement gasket. I'm going to look for a rebuild kit tonight. The car has been off the road for a long time however it has been shunted in and out of the garage on occasion and it is only recently that the reverse has failed. Cheers.

Thanks for all the suggestions, and the link to the correct filter. I have ordered one so we will see. The transmission seems to work fine in 1st, I don't have much road to test on as it is not road legal at the moment. A rebuild is probably due, but finding someone who can do it might be a challenge in the UK.

Hi two questions in one here. My 66 GS is having problems with the transmission in reverse. While it does reverse it needs a lot of revs and will not climb a hill in reverse. forward gears work fine as far as I can tell. it is not on the road at the moment. I am in the UK btw. 1 - does anyone have any suggestions to what this might be? 2 - i have read that this can be cause by a blocked filter in the gearbox, however I am having trouble locating the correct part. there seems to be two, one for the TH400 and one for the ST400 I believe the one in the Riviera GS is the ST400? can anyone point me to the right filter? I haven't taken it apart yet, I would rather not do that until i have the filter. any help would be appreciated. Cheers Simon.

Thank you very much for those photos, very useful, I should be able to fabricate something to match. and I think I know which clips you mean now, so hopefully I can find some or make something suitable. Much appreciated. Simon.

Thank you for your detailed reply. Unfortunately I am well past the point where this can be changed now, but I have attached a picture of the repair. Essentially there was nothing left of the original scuttle so a whole new flat piece of steel was welded in place. I am in the UK so getting hold of a repair panel was not possible at the time. Are the clips available at OPGI or do you have any pics of them. a photo of yours would be great if you have one thanks. We have test fitted the glass and the fit is good but there is just no place to hold the window in position when bonding it in. based on your description I suspect we will make up some mounts for the rubber spacers some how. Then it is just a case of getting the chrome to fix in place. Thanks

Hi, I have a 1966 Riviera that I am restoring and I have nearly got to the point of having to install the front windscreen. Unfortunately the car was in quite a bad way, and due to rust, any mounting fixture or features are missing from the scuttle panel. (not sure this is what it is called, I will hopefully attach a picture with the area I mean highlighted)I have been unable to find any pictures of the area online, apart from the attached picture. and the body manuals are not clear on what if anything is located here.Is anybody able to assist with photos or drawings of the scuttle panel?Essentially what I need to know is how the window is supported when it is fitted, also how the finishing strip attaches at the bottom of the window.Any help would be most appreciated.ThanksSimon.