John Vine Posted March 22, 2020 Share Posted March 22, 2020 R400D (2008), 6-speed box, 48K miles.Something odd happened with the gearchange during the 30-mile trip to my MOT yesterday. When I went to change down from 6th to 5th, the gearlever became very reluctant to move, and when I pressed on the lever, I could feel (hear, even) what seemed like poorly meshing gear teeth. It was as if I was attempting to make a poorly-synchronised clutchless change. After a couple of moments, I succeeded in changing down, and further downchanges (5th to 4th and so on) were ok. Up-changes were as normal. The same problem occurred just once more during the outward journey.Nothing untoward happened on my return journey, with all up and down changes silky smooth as usual.The box is the original, has been faultless since new, and hasn't been reconditioned in any way. I've yet to check the oil level, but there are no leaks and the car was serviced by Millwoods 350 miles ago.Could there be a problem of some sort with the synchro mechanism? And if so, why would the box behave impeccably on the return journey? Any thoughts, chaps?JV Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 22, 2020 Member Share Posted March 22, 2020 Could that be a problem with the selector mechanism? That would be easier to inspect and cheaper to fix.Jonathan Link to comment Share on other sites More sharing options...
Wrightpayne Posted March 22, 2020 Share Posted March 22, 2020 Sticking clutch possibly? could do an oil change and see if any bits come out (6sp has a drain plug)Ian Link to comment Share on other sites More sharing options...
elie boone Posted March 22, 2020 Share Posted March 22, 2020 Could it be the gearlever ball joint that has a lack of grease ? you can't reach it from the underside unless you have very little hands but if you undo the gear knob and pull the gaiter out you can about just fit the grease gun head trough the top of the gaiter to grease the ball joint. this would save to take the tunnel out. Link to comment Share on other sites More sharing options...
7 wonders of the world Posted March 22, 2020 Share Posted March 22, 2020 The spherical joint on the gear lever could cause a stiff shift however this would have no influence on the grating noise heard and felt.so assuming the clutch is clearing correctly...? then this is a syncro issue, sticking or worn ring or worn gear in the mainshaft which permits it to cockle a slight amount and not disengage or worn dogs on the hub or broken blocker spring.I would recommend tomorrow morning you call Steve Perks at SPC, he has redesigned quite a few 6 speed parts, after of course you've had a pee and made a flask and sandwich prior to calling.... https://www.tracsport.com/ Link to comment Share on other sites More sharing options...
John Vine Posted March 22, 2020 Author Share Posted March 22, 2020 Thanks for the feedback, chaps.Could that be a problem with the selector mechanism?I suppose it could be, but everything worked perfectly on the return trip, so for the moment I'm not suspecting selectors.Sticking clutch possibly? Clutch seems fine, and engagement is smooth. There's no graunching when selecting (non-synchro) reverse, so I think the clutch is ok.could do an oil change and see if any bits come out (6sp has a drain plug)That's a very good idea. I'll do that. It occurred to me that there might just be some rubbish in the box that had somehow got in the works. I'm assuming the drain plug is magnetic?Could it be the gearlever ball joint that has a lack of grease ?I don't think so as the lever action was as smooth as silk, even when the problem occurred.I would recommend tomorrow morning you call Steve Perks at SPC...Thanks for your diagnosis, Neil. I'm afraid you might well be right, so I'll do as you suggest. I'll also ask Phil Stewart of Road & Race Transmissions.More news later.JV Link to comment Share on other sites More sharing options...
Wrightpayne Posted March 22, 2020 Share Posted March 22, 2020 Could of course be user not prodding the left peddle enough! I've done it a few times in my driving life!But the next big question, what oil is going back in? Link to comment Share on other sites More sharing options...
sjl1 Posted March 22, 2020 Share Posted March 22, 2020 If this was a normal tintop obvious suspect would be clutch? Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted March 22, 2020 Leadership Team Share Posted March 22, 2020 If the clutch or clutch arm starts to fail it becomes most noticeable with difficulty selecting 1st or reverse, higher gears are much less of an issue.Stu. Link to comment Share on other sites More sharing options...
John Vine Posted March 22, 2020 Author Share Posted March 22, 2020 ...what oil is going back in?Now, that's a good question. What do you recommend? If I could still get it, I would go for Ford's original "red" gearbox oil, as specified for the Sierras. I used that in my 1.8K 6-sp and it was excellent. AFAIK, the oil has been in there since build, and is Caterham's own brand (Comma?). I guess the choice is between that and Redline MTL?I really don't think it's the clutch. There's no drag whatever when I select reverse, and other gear changes are generally super smooth. There's no judder, slip, grab or any of the other nasty symptoms. The entire clutch assembly (flywheel, driven plate, cover and slave) was replaced after my catastrophic clutch failure in France in 2015.I think 7WotW has the likely answer, and I'll be in touch with SPC and Phil Stewart.JV Link to comment Share on other sites More sharing options...
ECR Posted March 23, 2020 Share Posted March 23, 2020 My first thought was a cracked synchro ring. I had a few before I went dog box. Link to comment Share on other sites More sharing options...
John Vine Posted March 23, 2020 Author Share Posted March 23, 2020 Re #11:Thanks, Roger. That's exactly what Steve Perks has just suggested.So, I'm now contemplating removing the box and shipping it off for repair/refurbishment.Does anyone know how much a 6-sp box weighs? (I'll need that info for the courier.)And can anyone recommended a good courier? (I'm assuming I'd need insurance for around £2K.)JV Link to comment Share on other sites More sharing options...
ECR Posted March 23, 2020 Share Posted March 23, 2020 If no one has weights, can't imagine it'll be much different to a five speed box Weight of cast iron box (wet) 32Kilo Weight of alloy Quaiffe + alloy lid (wet) 29 Kilo Link to comment Share on other sites More sharing options...
7 wonders of the world Posted March 23, 2020 Share Posted March 23, 2020 John,Not sure where you are only you mentioned using Millwood for service so it might be quicker to pop up the M5 to Redditch in person....If you ask Steve first he may do it the same day for you or a worst courier it back down for you.You really need to send them in a wooden crate for piece of mind too. Link to comment Share on other sites More sharing options...
John Vine Posted March 23, 2020 Author Share Posted March 23, 2020 Re #14:Neil - West Dorset. Mind you, I think Boris's national bollocking on telly this evening has put the kybosh on any personal journey! Plenty of time to remove the box, though.JV Link to comment Share on other sites More sharing options...
John Vine Posted March 29, 2020 Author Share Posted March 29, 2020 An update....I spoke to Phil Stewart at Road & Race Transmissions. He thought my particular symptoms were unusual as they appeared to be intermittent and affected only 6th to 5th down-changes. He advised I first of all check the gear lever spherical bearing and the plastic saddle.I've just done both. The spherical bearing is as smooth as silk in all directions (this is the Quaife quickshift, I believe). (ETA: The bearing moves very slightly up and down in its housing -- is that a problem?)The plastic saddle looks ok but I'm not sure what a worn or damaged one would look like. Here's mine: I think I'll replace it anyway, but how do I get it out? I can reach it with long-nosed pliers but I don't want to damage it, just in case I have to re-use it.JV Link to comment Share on other sites More sharing options...
Wrightpayne Posted March 29, 2020 Share Posted March 29, 2020 John,I'd get your new one in hand then it doesn't matter how many pieces it comes out in!Googling images of the plastic saddle it should come out vertically upwards. Perhaps an allan key underneath and pull upwards to get it started? Ian Link to comment Share on other sites More sharing options...
John Vine Posted March 29, 2020 Author Share Posted March 29, 2020 Good idea, Ian. Thanks. I'll order one tomorrow.Of course, I won't be able to try it out on the road...JV Link to comment Share on other sites More sharing options...
7 wonders of the world Posted March 29, 2020 Share Posted March 29, 2020 I spoke to Phil Stewart at Road & Race Transmissions. He thought my particular symptoms were unusual as they appeared to be intermittent and affected only 6th to 5th down-changes. He advised I first of all check the gear lever spherical bearing and the plastic saddle........and that's why you need to send it to Steve in Redditch. The plastic saddle just clips onto the selector rail, long nose pliers will deal with it, you can get better versions from Steve, he offers a sintered metal version Link to comment Share on other sites More sharing options...
John Vine Posted March 29, 2020 Author Share Posted March 29, 2020 Re #19: Thanks Neil, but are you saying that Phil doesn't know his way around this box?JV Link to comment Share on other sites More sharing options...
7 wonders of the world Posted March 29, 2020 Share Posted March 29, 2020 I'm saying neither of the things mentioned in #16 would cause the symptoms you describe and any specialist should know that too. Link to comment Share on other sites More sharing options...
John Vine Posted March 29, 2020 Author Share Posted March 29, 2020 Re #21:I think Phil was simply recommending that I check a couple of things before embarking on a lot of work!JV Link to comment Share on other sites More sharing options...
elie boone Posted March 30, 2020 Share Posted March 30, 2020 I would consider a bearing that moves in his housing a problem, but i am no expert. Link to comment Share on other sites More sharing options...
7 wonders of the world Posted March 30, 2020 Share Posted March 30, 2020 some do have a very small amount of vertical movement noticeable when the lever is out of the car, however once fitted the clearance is taken up by the upward pressure on the lever.The bearing is not a tight fit in the housing and can be dis assemble to swap it position std ratio to quick shift by pushing it out with your finger - once the circlips are out.I have a spare in the garage with the same as John mentioned. Link to comment Share on other sites More sharing options...
John Vine Posted June 8, 2020 Author Share Posted June 8, 2020 Well, an update...I removed and cleaned the quickshift (already silky-smooth), and replaced the saddle. I didn't change the oil.So far, I've done 120 miles of mixed road driving, with loads of gear changes up and down through all 6 speeds. The change is about as smooth and slick as anyone could wish for, with each gear simply snicking into place -- no noises, no resistance, no drama. The lever now has practically no slop or slack, and it just feels in perfect order.I can only conclude that the synchros are working as designed. If that is indeed the case, the only significant difference is the new saddle -- in which case, my thanks go to Phil Stewart for his advice.JV Link to comment Share on other sites More sharing options...
Recommended Posts
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 accountSign in
Already have an account? Sign in here.
Sign In Now