9 replies to this topic

[Someone called James]

Hello Guys and Girls,

 

The original engine from my mini is currently part way through a rebuild and is completely stripped apart from the crankshaft, con-rods and pistons. I can't remove these until I've taken the gearbox off but I'm struggling to separate them. I've removed all the bolts and nuts I can see that hold the gearbox casing to the block but they still seem to be stuck together. Am I just being thick and missed something obvious or could they have rusted together - I'm pretty sure this is the first time they've come apart since being built in the factory!

 

Obviously, using something like a chisel to bang in between the block and the gearbox casing isn't a good idea so I might try suspending them from the engine crane slightly and gently tapping the gearbox casing downwards with a rubber mallet or something.

 

Has anyone got any ideas as to why they might not be separating? It's a 998cc A+ engine from a 1989 racing flame is that makes any difference. 

 

Thanks,

James.  

[nicklouse]

most likey you have missed two bolts that are hiding behind the engine front plate.

 

how many bolts and studs (or just the nuts) have you removed.

[AlexMozza]

They can get stuck on the dowels

[CAU998]

I know this may seem silly but there's no mention of you removing the clutch housing prior to you trying to remove the gearbox. I know you have more than likely removed the clutch/flywheel and housing but just thought I'd mention it as its impossible without doing so.

[Swift_General]

If everything If removed as described above, a suitable lever, careful used, and placed between the engine and gearbox on the exposed flywheel end will break any seal.

[Spider]

most likey you have missed two bolts that are hiding behind the engine front plate.

 

how many bolts and studs (or just the nuts) have you removed.

 

There's 6 bolts across the front side and 6 fasteners + 1 bolt / nut across the back.

[Someone called James]

I know this may seem silly but there's no mention of you removing the clutch housing prior to you trying to remove the gearbox. I know you have more than likely removed the clutch/flywheel and housing but just thought I'd mention it as its impossible without doing so.

 

Yes, I have removed the clutch housing and associated bits and bobs. The only things left on the block is the gearbox and the crankshaft is only connected to the con-rods and the pistons. 

 

 

most likey you have missed two bolts that are hiding behind the engine front plate.

 

how many bolts and studs (or just the nuts) have you removed.

 

 

OK, I'll have a closer look tomorrow. I'm pretty sure I've removed all the bolts and nuts I can see but I'll find the bag I put them in and count them tomorrow and report back. 

 

Thanks,

James C. 

[Cooperman]

Just look at the block to 'box interface and make sure all the bolts are removed.

If they are prise the block from the 'box.

[A-Cell]

Assuming all the fixings are removed as others have suggested.
Hang up the engine, with the transmission dangling in fresh air. Get a hide mallet, or soft faced nylon mallet and tap (not that hard) the gearbox front and back. The combination of the shocks and gravity will 'break the seal' of the gasket interface and transmission will drop off.
A block of soft wood, wrapped in rag and a hammer will suffice also.

[rww]

  I'm hoping you have seperated it by now but if not...............................

 

   There are two dowels at the rear of the block (manifolds side) one near the front pulley and one at the flywheel end. They can be a tight enough fit so that the block/gearbox does not want to come apart even though nothing else is holding it.From memory they can be knocked back into the block or at least disturbed enough to free the joint.

I've always been a bit wary of hanging the assembly on an engine crane and letting gravity do it's bit. If you do, make sure there is something soft for the gearbox to land on ! Beware the gearbox alloy is very soft and will not take kindly to a sharp object being inserted from outside the joint. I have found that you can access the joint from the flywheel end, where the 3rd main bearing cap, and lever (very gently)  at front and back from the inside to break the seal.