Mating a gearbox to an XK Engine

I’ve just replaced the clutch operating shaft on my 120 and fitted the gearbox to the engine (after a struggle!). Is there a recommended torque setting for bolting the gearbox to the engine. Thanks.

Thanks. Yes, tell me about it! I used an excellent plastic pilot tool from Moss Europe which lined it all up nicely. Even so, it took a good few attempts and several hours to get the engine at the right height to accept the shaft. All I need to do now is bolt up.

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Welcome Canary.
I also used that plastic Moss tool which worked fine for me.
Once you’ve done a few it won’t take hours, more like 10-15 minutes.
The bolts are 3/8-24 UNF and probably Grade 5, so you can use online torque charts, which say to go about 25-35 foot pounds.
https://www.almabolt.com/pages/catalog/bolts/tighteningtorque.htm
https://www.boltdepot.com/fastener-information/bolts/US-Recommended-Torque.aspx


http://www.americanboltcorp.com/tech/techtorque.pdf

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If you’re talking about gearbox to bellhousing, there’s no torque setting, just what is known in the UK trade as ‘FT’.

If you’re talking about bellhousing to rear of block, it needs to be within a very few millimetres if you’re going to bolt it up. Unless it is on the verge of clunking into position, DO NOT pull it into place with the bellhousing bolts. I’ve seen too many cracked b/housings to advise that action. Use a decent clutch alignment tool, leave it in 2nd or 3rd gear and wiggle the gearbox output flange until it clunks into place and you should be OK.

Edit - I’m sure you know this, but the alignment tool is used to assemble the clutch plate to the flywheel via the pressure plate, not to align the gearbox to the engine. Once the pressure plate has been tightened up, nothing’s moving anywhere, clutch plate wise.

2 grunts should do it :slight_smile:

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I can remember the times–painfully!!-- where I’d grunt and bitch and grunt and struggle, to get a tranny in.

After 30-40 minutes, I’d give up, slide out from under the car and wander off for awhile, doing some other task.

Go back later, take the support out from the rear of the trans, and…snick. The damn thing would just slide in!

Paul, I have noticed that phenomena with even lesser problems. Struggle for an hour trying to get bolts in the 3.8 starter, stop, have a cup of coffee and voila! they’re in. Or just say to h with it and come back the next day. MikeMoore

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For years I was ashamed to admit I had trouble getting my shaft into my baby’s spigot bearing. Now that I know there are other idiots out there with whom I share a common problem. … I feel much better.

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using a few longer pilot studs and bolts makes the job about 10 times easier (imo)

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I am not a role model, but I replace all of the bellhousing bolts with grade 8 studs and nuts. Makes things easier.

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When I first read this I thought it was a confession of a marital issue.

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Now, THAT’S how to start my Thursday morning!

:grimacing:

My wife often accuses me of being more married to my old cars than to her. I dare not say things like,

“cars don’t talk back,”
or

“cars are easier to understand because they come with repair and maintenance manuals”

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Thanks for all the replies. I didn’t try to draw the bell housing and block together using bolts as it was clear that entry had not been achieved. I took my time, used trial and error, adjusting the height of the block, lots of patience and got there in the end. The bell housing is now bolted to the block but not yet to final tightness which was why I asked about torque settings.

I’ve never used a torque wrench for bellhousing to block, on any car (I don’t play with moderns). Good and tight for the nuts and bolts, firm but not too tight for the bolts into aluminium castings. Never had a problem.

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Ditto: I’ll hazard a guess at 35 ft/lbs.

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Me 3. Twelve 3/8" bolts, including the three on each side that tie the angle brackets to the bottom rail of the block. More bolts than hold the gearbox to the bellhousing. I always use a load appropriate washer on aluminum. Fond of AN and NAS washer for general use.

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