It's not easy being green - 1971 TC

[jbcollier]

Spray liberally with penetrating oil.  Let it sit for a while.  Now try turning the bolts.  If they turn then also push/pull them out.  If they are truly frozen to the inner bush, then use a hacksaw blade cut them on both sides.

[BDA]

The bolts should come out with the use of the a hammer and a punch (or similar). In my experience with two different trannies (not a 336 unfortunately), the orientation of the bolt heads can sometimes cause it to drag on the case. Should that be the case, turn the bolt so that it is clear of the case. Then a hammer and punch can be used to knock it out. The only thing you'll need to worry about is hitting the case with your hammer.

If the bolt head is clear of the tranny case and you are still having problems, then jbcollier has the advice you need.

[EuropaTC]

Hi there,

I'd also try the penetrating oil for at least overnight and then try turning with a socket on the bolt head. If you can turn it then a combination of turning and leverage from the sacrifical screwdriver under the head is the way I'd try first. With any luck it'll start moving. If it turns but still won't move then I would try gently tapping the other end, again whilst turning.

The worst case is if the bolt is rusted solid to the steel inner tube on the inboard bush and the tube has disbonded from the rubber when you turn it. You're not going to move that without a press or very heavy thumping and in that scenario I'd try cutting the bolt , ideally with a 1mm disc but if you're really into masochism, then a cut down hacksaw blade.

Without looking at my car, can you get access to the bolts holding the steel bracket to the gearbox, drop the assembly and tear it apart on the bench ? 

Brian

[Cheguava]

Thanks to all for the responses - really helpful as always. I've just been out and soaked it all in PlusGas again - am out and about today so hopefully it can work its magic. Due to the closeness of the transmission casing I can't get a socket on the bolt head and so the impact driver can't be employed but hopefully it might be persuaded with kindness. Although thinking about that - if I put two nuts on the other end, where there is an inch of thread sticking out, and lock them together, I might be able to use the impact driver to spin the bolt free. Hmmm...

Brian's other suggestion about doing it on the bench is an excellent point which true to form I had not considered. Given I am going to lift out the engine and transmission, and then split them, I could then turn the transmission over and work on the problem from the top, with far better access, if the PlusGas and other methods don't free the bolts off first.

[4129R]

If you are using a drift to hit the threaded end of the bolt, cover the thread with a nut so you don't damage the thread. I have found those 3/4" heads jam against the gearbox casing unless exactly flat parallel to the casing, so I suggest using a 3/4" spanner to align the bolt before using persuasion with a drift and hammer.

When re-fitting those 2 bolts, put Copperslip on the shafts which go into the ally casing, so they come out easily next time.

[Cheguava]

If you are using a drift to hit the threaded end of the bolt, cover the thread with a nut so you don't damage the thread. I have found those 3/4" heads jam against the gearbox casing unless exactly flat parallel to the casing, so I suggest using a 3/4" spanner to align the bolt before using persuasion with a drift and hammer.

When re-fitting those 2 bolts, put Copperslip on the shafts which go into the ally casing, so they come out easily next time.

Good shout on the end of the threads - I shall be replacing all the nyloc nuts so will cheerfully bludgeon the old ones!  I'm also a devotee of copper grease - my dad got me a tobacco tin full to the brim of it purloined from his works, who used it by the barrel, 40 years later it's still half full so perhaps I skimped on ir  I suspect it will be far more empty by the end of reassembly! 

[Cheguava]

After liberal dousings in penetrating fluid, both spanners and hammers failed to budge the bolts holding the lower struts on. So will be plan B, remove engine and gearbox, and once engine and gearbox are split, turn the transmission over to try again, and if necessary, cut the bolts.  Lifting slings arriving tomorrow, so we shall see how the Temu hoist and leveller perform. Doesn't look like cheese, but we shall see.

[Cheguava]

So, engine and transmission lifted out pretty easily, lowered onto wooden supports so I can take off the transmission and attach the engine to the newly purchased engine stand. This is a really dumb question, but if I remove the starter motor (done) and all the bolts between engine and bellhousing, the transmission and bellhousing should separate from the engine? I undid all the bolts and it did seem like there was wiggle movement, but not inclined to separate... I've been searching for threads on here, and read the manual repeatedly, I just don't want to break anything!  Am I missing something? Pretty certain I got all the bolts... 

[BDA]

Did you take the bottom part of the dust shield off? It's usually held on with one bolt that screws into the bell housing.

[Cheguava]

Did you take the bottom part of the dust shield off? It's usually held on with one bolt that screws into the bell housing.

D'oh!  I thought the shield came away with the bellhousing!    I felt the bolt, will remove it and have another go. Thanks BDA!

[Cheguava]

Did you take the bottom part of the dust shield off? It's usually held on with one bolt that screws into the bell housing.

D'oh!  I thought the shield came away with the bellhousing!    I felt the bolt, will remove it and have another go. Thanks BDA!

And just like that, the transmission was off (a little very gentle pulling and prying). Will assemble the engine stand and mount the engine  later this week.Feels like a fairly apposite way to conclude the year, with the car almost as far away from completion as it can get. Hopefully 2025 will see progress in the right direction, although I'm braced for plenty of setbacks along the way. Thanks for all the help users of this form have given me so far, and wishing you all a fantastic 2025. 

[BDA]

 

I'm sure 2025 will be the beginning of solid progress on your baby!

[Cheguava]

So, clutch cover came off nicely, and the friction disc fell out, looks pretty good condition tbh but might as well replace whilst I have everything apart.

Need to get the flywheel off to mount onto the engine stand, and for the life of me can't see online what size the 12 point bolts are that hold on the flywheel. Seen a reference to 7/16, but could anyone confirm before I order a socket?  Probably missing something obvious...

At least I can use the time to work on the transmission case and get the lower struts removed from it.

 

[BDA]

I don't know the size of those bolts. I'd just keep trying sockets till one fit. It's almost certainly Imperial and not metric. I think the bolt pattern is regular, meaning that you can put the flywheel on any one of six ways, but remember that your timing is done on the flywheel so make some mark on the end of the crank so you can clock the flywheel correctly.

Someone here once said something to the effect of, "if you see the clutch, change the clutch." I think that's good advice, especially if you don't know the history of it.

I watch a youtube channel from a Brit engine builder, "Barum Engines." When they balance their cranks and flywheels, they also balance the clutch cover. That obviously makes sense but I guess they assume the clutch cover will not be changed when the clutch disk is changed. I don't think I'd replace my clutch cover unless there was something wrong with it but maybe I'm living on the edge! Just a thought...

[4129R]

So, clutch cover came off nicely, and the friction disc fell out, looks pretty good condition tbh but might as well replace whilst I have everything apart.

Need to get the flywheel off to mount onto the engine stand, and for the life of me can't see online what size the 12 point bolts are that hold on the flywheel. Seen a reference to 7/16, but could anyone confirm before I order a socket?  Probably missing something obvious...

At least I can use the time to work on the transmission case and get the lower struts removed from it.

I don't know for sure, but I seem to remember using a 1/2" drive into a 9/16" socket to undo those bolts. So my betting is it is a 9/16" socket you need.