When I pulled the motor apart I put the bits in little bags- when I put the block and gearbox back together I used all new bolts but there were no studs in the original lot but also not enough bolts - some were missing when I pulled it apart - so I guess there were no studs originally.

Only one hole won't take a NFC bolt -thats next to the crank at the radiator end so I guess this is a stud hole? Is the other on the other side of the crank? If so it's got an NFC bolt in it now

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

They are all 1/4 UNF bolts except for 2 studs which are 1/4 UNC but these are next to teh dowel ( clutch end) and 3rd hole back front the radiator end.
i assumption you are talking about the engine/gearbox bolts?

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- 1962 Beige Delight club car, Rebuilding.
- Motorkana Special
- Minor Mishap, 1958 Morris Minor

-- Last ever Tea Lady at Longbridge--

Well there are 1/4" UNF bolts in those holes - not forced done up with fingers first before spanner so guess someone has retapped the holes

Any reason why they were studs and not bolts?

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

These 2 studs are UNF both ends.
They are screwed into the block, so UNF not UNC. This applies to ALL the front and back bolts as well that hold the gearbox up to the block.
They used 2 studs there because bolts are a little awkward to get in.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

You are correct the should all be UNF

find the silly twit who designed it and ask him. and also ask him why he thought it was good idea to make it so the distributor drive wont come out at certain crank angles.
If you are making a big HP motor it is not a bad idea to change them all to 5/16" UNF. Mainly BIG torque motors can flex thsi joint and cause the bolts to become lose as it compresses the spring washer into the alloy case and then when it relaxes it can cause the bolt to have less tension on it.
Have seen it twice, once on a 1460 and once on a 1250

_________________
- 1962 Beige Delight club car, Rebuilding.
- Motorkana Special
- Minor Mishap, 1958 Morris Minor

-- Last ever Tea Lady at Longbridge--

Funny thing is the studs make it no easier imho...you'll get them in Wombat, even if you have to undo all the bolts by a turn to allow something to shift a fraction.

I perhaps wondered if the studs helped the factory align the gearbox to the block quickly when assembling as well? I know if you go at it too quickly the gaskets will shift without something to hold them in place. The large dowels are there at the end, but only have a very short reach.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

i think cap screws might make it a bit easier if you can get a driver with a uni joint in it.

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the world is a book, and those who do not travel read only a page
66 Mini Minor sponsored by http://www.lifeonthehedge.com.au/ The Dog Harness Specialists
It was a pleasure ausmini. I'll miss all you misfits and reprobates

I had a Mk1 S (thin flange) ex-race motor with 5/16" UNF capscrews fitted. They were a right PITA to do up... I had no ball-end hex keys back then.
I've never had oil leaks with overbored thick flange blocks, even with the original 1/4" UNF bolts.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.