10 replies to this topic

[MiniMadMick]

I have just finished stripping the engine down from my 1964 Morris 850.
The engine had developed a knock at higher revs, I found flakes of steel in oil (can't be a good sign) anyway I have since traced it to the big end of No 2 cylinder, which has caused some surface damage to the crankshaft and there is also scoring in the bore.
Ok exchange crankshaft
My questions are do I need to change the con rods and if so are all the con rods on the small block motor the same as when I do a search for 850 con rods nothing comes up
Where can I get oversize pistons from as again nothing comes up when looking for 850 pistons I am not a purist so the pistons don't need to be original
I am thinking of changing the cam while I have the engine in bits can I change to slot drive by simply changing the oil pump to match as pin drive cams are not as readily available
by the way I live in Australia

[Leonrjohnson]

I dont see why the conrods need changing, as long as they are still OK. I would get a machine shop to crack test and resize, align them for reuse.

The crankshaft may be able to be ground undersize to restore it for use: a machine shop should be able to tell you if it is reuseable.

As for pistons: I buy almost all my Mini bits from Minispares UK as their prices and service are second to none.( http://www.minispares.com ). Check their online catalogue.

If you keep the order plus frieght below $1000 per shipment, no Import Duty is required!

Do you really want to keep the 850? 998 is a better and more modern model in my opinion.

[MiniMadMick]

Thanks for the advice, I plan on keeping the 850 as I have a Cooper S also sentimental value I suppose, need to find a machine shop locally to do the re-bore got a price of $2500 don't know what planet they were on.
I am probably better calling the Minispares as I can't find the pistons online.

[Carlos W]

Thanks for the advice, I plan on keeping the 850 as I have a Cooper S also sentimental value I suppose, need to find a machine shop locally to do the re-bore got a price of $2500 don't know what planet they were on.
I am probably better calling the Minispares as I can't find the pistons online.

 

Remember, you get 7.5% off at Minispares as a TMF+ member

[grumpy dad]

Hi

try this

 

http://www.minispare...98.aspx|Back to

 

http://www.minispare...px|Back to shop

[MiniMadMick]

The 948 has the same bore as the 848 does anyone no if I can use the pistons from the 948 as an alternative as + 030" are available from Minimanaia and can anyone answer my question regarding changing from pin drive to slot drive

[grumpy dad]

Hi 

yes pin to slot 

just change the oil pump 

[MiniMadMick]

Thank you

[Cooperman]

Hi Mick,

 

I also have an 'S' (1964 rally car) and I'm currently doing a full resto on a 1964 850.

Pistons are hard to fine and I recommend F.W. Thornton of Shrewsbury who may be able to help.

Ph: +44 (0)1952 252892     Fax: +44 (0)1952 246082

e-MAIL: [email protected]

 

You won't need new rods and you should get away with a crankshaft re-grind. It is a good idea to use new pinch bolts to secure the gudgeon pins, although they must be the correct ones and again can be hard to source.

Here you would expect to pay around £100 for a re-bore to match new pistons. A crank re-grind would cost about £75. Plus the cost of bearings & piston. Block skim comes at around £30 as does skimming the head surface. Also the 850 block does not have cam bearings, the cam runs straight in the cast iron block. This is far from ideal when restoring and most people have the block line-bored and standard cam bearings fitted by the machine shop. You wil ned the sizes to bore the cam bearing housings and I don't have this to hand, but I can get it for you (and, eventually for me).

On mine I'm still doing the body restoration, so the engine is some way off. If it looks too difficult & expensive I may just fit a pre-A+ 998 with all 850 ancilliaries, but would prefer to use a genuine 850 to give it full value when finished. The original 850 is getting a rare car now.

Edited by Cooperman, 22 April 2014 - 12:40 PM.

[MiniMadMick]

Thank you managed to find pistons, having been told by both Mini Sport and Minispares that they are not available I managed to get them over here in Australia they are not original but a pattern part.

[Morry Stu]

Where you at MiniMadMick.

Parts for 850 should be freely available here in Aus.

ACL should make them. If not try JP engineering in SA. http://www.jp.com.au/JPPistons.html

Minisport.com.au in SA

Morris Minor World in Sydney.


As far as cam/ oil pump go you can keep the orig pump and just get the cam re-ground. There are a number of grinders who can do it.

Clive Cams in Vic

Waggot in Alstonville ( Waggot would be my choice. They re-ground mine to Cooper S spec and also faced and hardend the lifter and lobes with a phosphourus etching )

Camtech.

PM me if you need further info.