Jonah Posted April 27, 2022 Report Share Posted April 27, 2022 My Spitfire Mk3 gearbox crunches into second gear, it has a D type overdrive I’m wondering if is this likely to be a synchro problem requiring replacement or could a clutch problem be the cause? thanks in advance for any advice for a wishful thinker! Link to comment Share on other sites More sharing options...
Clive Posted April 27, 2022 Report Share Posted April 27, 2022 Either or both! Check the cluch is moving nicely with no excessive play in the system. And the pin hasn't partially fallen out the bellhousing But if it is only into 2nd, not 3rd under similar revs etc, chances are the synchro is worn. 2nd tends to wear rather faster than the others. Link to comment Share on other sites More sharing options...
johny Posted April 27, 2022 Report Share Posted April 27, 2022 yes almost certainly synchro and unfortunately a complete gearbox stripdown to replace it. Its like a miniature clutch and they wear out just like the main one then if you keep crunching other components in the gearbox can suffer. In the meantime after pressing the clutch try waiting a fraction before changing up and on down changes learn to double declutch😲 Link to comment Share on other sites More sharing options...
Jonah Posted April 27, 2022 Author Report Share Posted April 27, 2022 Thank you Clive. If the clutch is ok which is is the most straightforward way to remove the gearbox? Link to comment Share on other sites More sharing options...
Jonah Posted April 27, 2022 Author Report Share Posted April 27, 2022 Thanks Johny I feared a strip down might be the solution Link to comment Share on other sites More sharing options...
Clive Posted April 27, 2022 Report Share Posted April 27, 2022 Disconnect Battery, Remove one, or both seats. Remove H frame. Remove the tunnel. Undo speedo cable. Undo propshaft and disconnect. Remove the slave cylinder from the bellhousing. Support the engine under the sump, undo the gearbox mounts. Jack the sump up a tad to lift the gearbox tail. Remove starter motor, and undo all the gearbox to engine bolts, leaving the top 2 in place. When ready, indo the top 2, and slide the box back and off/out. Heavy! Find a good used box, same as herald (unless yours is overdrive) Or get yours rebuilt. To refit, it is teh reverse. EXCEPT get 2x 3"+ bolts, 5/16 thread, and cut the heads off. Take the 2 studs out of the block which are the 2 top fixings, and replace with your new special studs. These make refitting the box MUCH easier, as it keeps everything perfectly aligned. 1 Link to comment Share on other sites More sharing options...
Josef Posted April 27, 2022 Report Share Posted April 27, 2022 I would advise rebuilding rather than dropping in another used one. It’s relatively easy to do, and getting them in and out is enough of a struggle that you don’t want to do it again in a hurry if the used one turns out to be not up to much! (Just built and swapped one each in my Spit and Herald) Link to comment Share on other sites More sharing options...
Jonah Posted April 27, 2022 Author Report Share Posted April 27, 2022 I’ve been thinking of buying a mobile lift/tilter from CJ Autos to raise the car, do you think it would be possible to remove the gearbox from below using this? Link to comment Share on other sites More sharing options...
johny Posted April 27, 2022 Report Share Posted April 27, 2022 no the gearbox has to come out from inside or lifted out complete with the engine. Thats the disadvantage of having a separate chassis... Link to comment Share on other sites More sharing options...
Jonah Posted April 27, 2022 Author Report Share Posted April 27, 2022 Thanks everyone, do you know if a standard rebuild kit is available Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 27, 2022 Report Share Posted April 27, 2022 there are rebuilds made up as a "kit" but i would say you need to look see first if luton is too far a run for me to guide you can you find someone in your local area who can advise if all is quiet and only 2nd is failing you may only need a set of circlips and a new baulk ring not a whole kit there are a few things in the tooling like circlip pliers , a mallet and steel punch and a dummy lay spindle do you have a decent workshop manual ??? pete Link to comment Share on other sites More sharing options...
Clive Posted April 27, 2022 Report Share Posted April 27, 2022 1 hour ago, Jonah said: I’ve been thinking of buying a mobile lift/tilter from CJ Autos to raise the car, do you think it would be possible to remove the gearbox from below using this? I bought a (used) version f that lifter. It is difficult on aspitfire, as it lifts under the sills (but mine wasn't narrow enough) so you would end up with lifting the tub, with the chassis and engine etc hanging off the body. Not ideal. I sold it and rely on a good high lift trolley jack and tall axle stands. I also stack 2 or 3 wheels under the centre if the car, just in case.... Next. Beware buying a kit. The quality is variable. The better rebuilders have a supply of good used components, and will swap synchos around. Or use good s/h synchros. Bearings may well be fine, in fact anything that is in good condition is worth reusing. For refence, I had my type 9 box rebuilt by BGH, they supply lots of Ford specialists, rally chaps etc. They were happy with most of my box, but it had previously been fitted with repro synchros. They fitted used Ford items. They also changed 5th gear (mine was nearly through the hardening) and reground the synchro hubs etc. No new parts at all except gaskets etc. Link to comment Share on other sites More sharing options...
Jonah Posted April 27, 2022 Author Report Share Posted April 27, 2022 Yes, I have the green Triumph Workshop Manual thanks Julian Link to comment Share on other sites More sharing options...
Jonah Posted April 27, 2022 Author Report Share Posted April 27, 2022 I’m going to need some guidance I think once I’ve got the gearbox out as I haven’t done this before Thank you Clive, ill skip the lifter idea, I’ve been searching for a safe way to lift the car so I can work underneath, I’ll keep researching! julian Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 27, 2022 Report Share Posted April 27, 2022 you only need to lift the front enough to get to the bolts around the bell housing once removed you can drop it back on the deck with OD its going to be a bit heavier than it looks , def seats out and some remove the steering wheel to aid access. green WSM .... thats a good start but you dont need any Churchill special tools on these gearboxes a dummy lay spindle (made from anything) a set of punches a hammer circlip pliers being overdrive has some advantages (as on a std getting the speedo worm off can be a faf ) spares get a gasket set new synchro baulk ring , some ep90 gear oil ,and 2 or 3 mainshaft3rd gear circlips as never re use and you may overspread one on refitting so a spare is useful to have bearings tend to be always reusable tube of sealer etc Pete Link to comment Share on other sites More sharing options...
Clive Posted April 27, 2022 Report Share Posted April 27, 2022 1 minute ago, Jonah said: I’m going to need some guidance I think once I’ve got the gearbox out as I haven’t done this before Thank you Clive, ill skip the lifter idea, I’ve been searching for a safe way to lift the car so I can work underneath, I’ll keep researching! julian I have tried all sorts, and concluded tolley jack and stands are easiest. Mobile axle stands (google them) are really good, and aloow you to shuffle a car around if space is tight. Link to comment Share on other sites More sharing options...
Josef Posted April 27, 2022 Report Share Posted April 27, 2022 Give this guy’s series on a gearbox rebuild a watch. It gives you a good view of what everything looks like (though there will be differences if you have a 3 synchro box) and explains some stuff the wsm misses or doesn’t make super clear. Link to comment Share on other sites More sharing options...
Jonah Posted April 27, 2022 Author Report Share Posted April 27, 2022 Thanks Pete, would it be sensible to replace the synchros on all gears? I’ll look into the mobile axle stands Clive, my problem has been getting a low profile trolley jack underneath to start with Link to comment Share on other sites More sharing options...
Jonah Posted April 27, 2022 Author Report Share Posted April 27, 2022 Thanks Josef I’m on it 1 Link to comment Share on other sites More sharing options...
johny Posted April 27, 2022 Report Share Posted April 27, 2022 1 hour ago, Jonah said: Thanks Pete, would it be sensible to replace the synchros on all gears? The problem seems to be finding good pattern part synchros as some might not work very well or last long so it would probably be best to swop rings around as much as possible. You can inspect and check the original rings and use the best on 2nd gear then use the replacement on 1st or 4th depending on whether yours is a 3 or 4 synchro unit.... Link to comment Share on other sites More sharing options...
Clive Posted April 27, 2022 Report Share Posted April 27, 2022 1 hour ago, Jonah said: Thanks Pete, would it be sensible to replace the synchros on all gears? I’ll look into the mobile axle stands Clive, my problem has been getting a low profile trolley jack underneath to start with Sealey do one. Or if feeling flushed, buy a weber https://www.weberuk.com/shop/trolley-jacks/standard-trolley-jack/wdk20/ which is rather nicer to use Some cars need the front wheels to run up onto 1" thick planks. Re synchros, the hubs may well need resurfacing (with fine abrasive paper) to give a bit more grip on the synchros Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 28, 2022 Report Share Posted April 28, 2022 there is /was a problem with new rings some have been turned up on a lathe and the chuck jaws distort the ring so it becomes lobed totally useless simple hand test is to twist/wring the ring onto its gear cone it should grip quite easily and there must be a decent few mm gap between the ring and its gear face or its bottomed out will load a how it works but need to be on my PC not lounging Pete Link to comment Share on other sites More sharing options...
Josef Posted April 28, 2022 Report Share Posted April 28, 2022 I did buy a single County branded synchro ring from Paddocks which is now in my Herald. It looked ok, felt positive on the gear cones, and so far seems to be working fine. Link to comment Share on other sites More sharing options...
Clive Posted April 28, 2022 Report Share Posted April 28, 2022 I would use the 4th gear syncho on 2nd, and put a new one on 4th where it won't get much grief. Link to comment Share on other sites More sharing options...
68vitesse Posted April 28, 2022 Report Share Posted April 28, 2022 Mike Paworth, based in Coventry, was very helpful for advice and parts when I broke my Vitesse gearbox. I lift engine and gearbox out as a unit, only tried through the car once, but depends on equipment available. Regards Paul. Link to comment Share on other sites More sharing options...
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