Rebuilding My Triumph Spitfire Gearbox 1 - Disassembly 

Even professional shops screw up. That seems a pretty easy thing to have double checked though... Good thing you found it early on!

No problem 👍 Reverse causes issues on a lot of these. Usually it's decades of letting the gears crunch into place.

Thanks Steve! Your channel looks like it's picking up subscribers too. Nice work!

@@midwestmotoring thanks! Trying to share my journey with others.

If I'm right, it's the same gearbox as in the Spitfire 1500. Very similar to the video, just with a different top cover and shifting mechanism. Good luck!

Good call on the copper pipe. And I like the idea of removing the bellhousing soon in the job.

Thank you very much!

I've gotten a lot from Rimmer Bros in the UK, and from another gearbox I have. Thanks for watching!

In this video that's just part of the cart that it's on. I think it may have come from Eastwood. You can go directly to their main page, but if you use this link I get a small commission if you buy anything, so it helps the channel: www.jdoqocy.com/click-101203753-14053814.

Yes, that will work. However, I'd see if you can identify where the noise is from before going that route. It's not necessarily the gears. Could be a bearing somewhere, the oil pump, or a number of other places. Make sure the mainshaft isn't chewed up. That's pretty common in Spitfires, and you may need a new piece.

Offhand I don't recall if it needs to be, but I typically would remove it first. A soft faced hammer may be necessary to separate the pieces.

I've got both a Haynes manual and the factory workshop manual. I find the Haynes one easier to follow though.

@@midwestmotoring thanks for the swift reply! That's great thank you. I've got the workshop manual but will grab myself a Haynes manual as well. Thanks from the UK!

That one I'm not sure about. By "spacer" do you mean the sleeve that the pin inserts into? If it's still in place and if it's in the way, I'd use a punch to push it out--just get one that's the right size so it doesn't get stuck in the middle. Worst case scenario you can use a drill bit to remove the material until it comes loose, then replace the sleeve with an appropriate bushing from a hardware store. A bushing with an appropriate size and strength bolt to replace the pin will work if you're having trouble keeping everything in place (i.e. if the pin is falling out on reassembly).

@@midwestmotoring Thanks for the insight Great video by the way After the struggle to remove the gearbox, I only want to do it once. Trying to source the cause of all the oil in my bellhousing.

Hi Denis, sorry for the late reply. Getting the pieces together is one of the more difficult parts. It's important to have a dummy shaft to put in the overdrive. If everything isn't lined up, the tailshaft of the gearbox won't fit into the splines of the overdrive.

My gearbox is an FH unit, which were originally fit to Spitfires from Mk IV cars until whenever they introduced the single rail boxes (FK units). It's a 3-rail gearbox with a D-type overdrive--very similar to what would have been fit to a GT6 but with different gear ratios. The J-type overdrive you have will be different from this unit, though the concepts and how the unit operates will be the same: The mainshaft from the gearbox turns a cam, which operates the oil pump, which builds hydraulic pressure using the gear oil. The operating valve (moved by the solenoid) either releases that pressure or uses it to force some pistons to move the sliding member against some springs. The sliding member forces power from the gearbox to go either directly to the tail shaft (part of the annulus) or through a planetary gearset first, which introduces another gear. There are some differences in how much pressure, how the valves are operated, and where the springs are attached, so you'll want to consult a shop manual specific to the J-type unit. For anyone with an A-type overdrive, there are some pretty strong springs that work against the hydraulic pressure, and you want to be careful to not just pull off bolts in any order or you could damage the unit or injure yourself. I'm not sure if a J-type has anything like that, but it's best to check before proceeding. In principle though, the overdrives are very similar.

@@midwestmotoring cheers for the reply,i gotta get my spit on the road asap. Thanks from myself in getting sunnier Scotland.

John, am I reading correctly that you are hearing a noise, but only when shifting and the clutch is in? That sounds like a release bearing to me. It's still a gearbox-out job since that's in the bell housing, but it doesn't require rebuilding the trans. I'd replace the other 2 clutch pieces while you're in there since it's not fun to pull the gearbox, and of course pull the top cover off and check for broken teeth or general "looseness." As for whether it's similar to a Spitfire gearbox... in a word yes. They have different measurements of course, but it's pretty similar internally. The main difference is that the TR6 bellhousing doesn't unbolt, and the remote shifting is a little different. The gears and bearings are, of course, also a bit larger. If I run out of projects to film, I actually have a TR6 gearbox sitting in the basement that I'll rebuild, though fortunately it's not a necessity now.

@@midwestmotoring Yeah, I have run into the bearing noise itself before in my old 320i BMW, only there it was the input shaft bearing. TO bearing didn't solve the noise in that one. The main noise that I have is the loud gear noise while driving that increases with engine RPM. A shop told me they thought that it was the diff, but its definitely the trans.

I should put my little gopro in the trans area to record!

@@jamcdona Ah! It's a clue that it changes with RPM and not wheel speed. I'd bet your throwout bearing still needs replacement, but if the noise also happens while driving then the usual culprit is the layshaft. It's one of those things that, if you're replacing one piece, you may as well do the rest since you need to tear it down anyway to get at it. I'm happy to help you rebuild your gearbox if you're having trouble. Contact us through www.mwmotoring.com and we'll chat about it.

@@midwestmotoring , are you subscribed to 6-Pack TR6 club? You and a few others could contribute articles to keep 6-pack going. You know your stuff, and probably have some great stories from past cars, also. They need an editor, also...in case you find yourself with extra time ;) 6-pack club magazine is so much better than others like 'Alfa Owner'. We have grease under our nails, they have wine-tour dust on their Alfas. I'm an owner, know!