automatic engine block

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woodypup59
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automatic engine block

Post by woodypup59 »

Whats the difference between an auto and manual block - apart from the dip stick hole ?

Also is an auto crank different to a manual (998) ?
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whistler
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Re: automatic engine block

Post by whistler »

One of the diffferences in the blocks is around where the oil pump sits.

The crank, rods and pistons are the same as manual as far as I remember.
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mab01uk
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Re: automatic engine block

Post by mab01uk »

1275 Auto Block- Convert To Manual (With Pics)
To fit a 1275 auto block to a manual, apart from drilling the dipstick hole, there are a few mods needed to oil plumbing:
1. Auto block doesn't have the drilling all the way from the oil pump to the relief valve.
2. Auto block has 2 holes in the relief valve seat `cotton reel' to let oil get into the main gallery, because the normal filter flange is blocked off with a plate- the motor's lube oil comes UP the banjo pipe from the auto trans to the motor.
3. Auto block pump mounting recess is .250" deeper than in a normal 1275 block.
AusMini Link:-
http://www.ausmini.com/forums/viewtopic ... 25&t=90470
Polarsilver
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Re: automatic engine block

Post by Polarsilver »

Well i never knew that .. i learn something new everyday :)
mnicoop63
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Re: automatic engine block

Post by mnicoop63 »

Here is a pretty good link that tells you everything you need to know in order to take an auto block and make it work on a manual gearbox.

www.home.earthlink.net/~roygmisc1/conve ... vert1.html
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Re: automatic engine block

Post by indigo »

Can this mod be carried out on an A+ 1275 block, or is this a different kettle of fish?
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Jt850
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Re: automatic engine block

Post by Jt850 »

indigo wrote: Wed Jun 10, 2020 6:33 am Can this mod be carried out on an A+ 1275 block, or is this a different kettle of fish?
Yes, looks like you’re in Australia. Give Matt Read a call in Brisbane (ReadSpeed). He has adapter plates etc made up for them and help you what else needs to be done. He did mine for me. Turned out a cracker engine, so much torque!
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Re: automatic engine block

Post by agricola »

please see this thread on this forum
viewtopic.php?f=3&t=16214&hilit=auto+block
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Spider
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Re: automatic engine block

Post by Spider »

indigo wrote: Wed Jun 10, 2020 6:33 am Can this mod be carried out on an A+ 1275 block, or is this a different kettle of fish?
Yes, I have done a few and also an MPI Auto Block.
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Re: automatic engine block

Post by agricola »

most import point is the 0.250 plate must be an interference fit in the block, and from the 2 blocks I did the od varies ever so slightly they are best custom made. Other than that straight forward and Block Crank & rods nicely age stressed relieved
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Glacier white
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Re: automatic engine block

Post by Glacier white »

It feels as if i want to swim against the tide, but i am thinking about converting my Austin 1300 from manual to automatic at some point. Apart from getting old and lazy and all that, i seriously admire the AP automatic as an engineering achievement.

Now i know that the obvious way to move on would be to replace the complete engine / gearbox as a unit and remove / fit whatever else is required, but having a perfect engine that i was honing for years, it feels a shame not to try and mate my curent block (A+ from early nineties) with an AP automatic from the same period. Reading the posts above on the reverse procedure, it does sounds feasible, and as far as i know the casting number remains the same, WFM 1024. I wonder though if there is any catch.
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Spider
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Re: automatic engine block

Post by Spider »

I would be possible, though some work.

The back end of the Oil Pressure Relief Valve Drilling will need to be plugged up Oil tight, then the Oil Pump recess in the Block lowered by 0.250".

The Auto's have a different Oil Pressure Relief Valve Seat, that's easy to change. The Oil Filter Head Oil Way needs to be covered, there's a standard plate for that and finally, the Dip Stick Hole needs to be plugged. On some blocks, they fitted a plug similar to the Main Gallery Plug used in later blocks.

I would suggest though, getting all the parts together, including a new Oil Pump (the Autos are different) before laying a spanner on any of it.
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Glacier white
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Re: automatic engine block

Post by Glacier white »

Thanks for the confirmation Spider.
Indeed, it doesn't seem to be difficult, even if i have to dismantle the block completely for the machining, but in any case it beats having to prepare another block from scratch.

You are right though, i have to gather all the parts first, and maybe find a suitable donnor.

On a different note, i suppose that the crown wheel and pinions are specific for the autos, but i wonder if i could use the manual diff output shafts, in order to retain the current driveshafts.
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Re: automatic engine block

Post by Spider »

The Crownwheel and Pinions are indeed different for the Autos, these are on 4.5" Ctrs where as the manuals are on 4.0".

The other parts of the diff are the same though, so you'll have no issues with that, but the earlier autos did use all steel Hardie Spicer Universals, same as the Cooper S, so the Diff Side Covers for these are sized to suit them and these are also unique auto parts. The later boxes (not sure of the C/P) did have Pot Joints so the early Rubber Uni Yokes will fit these side covers OK.
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