replacing 803 engine & Gearbox with 948 or 1098

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brucek
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by brucek »

That's right Roger. It's a very effective and low cost way to improve the overall performance without affecting the original look of the interior of the car. Many consider the 948 to be the best engine used in a Minor. It is certainly 'sweeter' than the later 1098 and there is not much difference in overall top speed between the two. Good luck :D

dellerie
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by dellerie »

rogerowen wrote:This is getting interesting! Have I stirred up a Hornets Nest? The way I see it - you replace the 948 gearbox back section with the original 803 back section (i.e. no remote), and the original 803 long gear-stick connects with the 948 internals. this way the gearbox tunnel of the 803 car does not have to be changed to a 948 one.
that's what i am guessing. my original concearn was that the 803 stick wouldn't 'fit' the 948 internals as it would be in different place. i understand the theory behind the gear ratio's and the front of the box
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by dellerie »

tried doing this today and have a slight problem.

i have removed the 948 tail and replaced with the 803 tail. ok. without any of the 9 bolts in, the shaft turns nice a freely. when i nip the bolts up, the shaft doesn't turn. it's stiff and will not rotate. undo the bolts again and it turns freely.

there are 2 shims that sit on top of the bearing. on the tailshaft there is a circular rescess where i presume these sit. is that where the proble lie's? or am i overlooking something still.......

you lot said it was easy......... i hate that saying..........
bmcecosse
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by bmcecosse »

Can only suggest trying different shims until it's just right!
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dellerie
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by dellerie »

only snag is that i have tried with the shims and without.

any other idea's?
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by MarkyB »

Is there a gasket between the two parts?
If there should be, and you are putting them together without it, that might explain it.

"Once you break something you will see how it was put together"
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by bmcecosse »

Yes - ^^^^ that's what I was wondering..... Could be worth trying it with 2 gaskets I supppose - although that shouldn't be necessary....
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rogerowen
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by rogerowen »

A very knowledgeable Morris owner has mentioned this problem, it seems you just have to keep trying different amounts of shims.
That's strange R2, the damage doesn't look so bad from here!
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by bmcecosse »

Yes -but I gather it's still going solid even with NO shims.......
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dellerie
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by dellerie »

it is indeed bmc. i have fitted a new gasket, used 2 shims, 1 shim and no shims. doesn't matter which way i do it, it will not turn once i have nipped the 9 bolts up. with the bolt's loose, it turns freely.

i am stuck and extremely frustrated now. i am wondering whether i should just collate my stock of 3 gearboxes and scrap them and just stay as i am with the 803 box. i have spent far too long on this now and it's not worth the agrro.

anyone else have an idea?
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by bmcecosse »

Try the two gaskets! Can't do any harm...
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dellerie
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by dellerie »

bmcecosse wrote:Try the two gaskets! Can't do any harm...
i shall make a gasket from the cornflakes packet then!
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by bmcecosse »

You have two gearboxes there - so you should have two gaskets.....
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dellerie
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by dellerie »

well i had another crack at this today and after using 2 gaskets (one made from a cereal packet), i've got the thickness i needed and have bolted it back together and it turns freely. :D
i lifted the side cover plate and had a peak, all looked fine to me. newish in fact (goldseal box anyway)

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all thats left to do is to fit a tailshaft seal, fit a gear lever and give it about 5 coats of bmc paint. it should be good for fitting then at a later date.
mike.perry
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by mike.perry »

Gold Seal means that it was factory rebuilt 30 years ago and has done 50,000 miles since so don't take the condition for granted
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bmcecosse
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by bmcecosse »

It may have been reconditioned 30 years ago - but it may have had little use since! I have a gold ribbed box that looks NEW inside - no wear that I can see on the dog teeth or on 1st gear teeth on the laygear.
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by MarkyB »

Basically you wont know until you try it!
I'd be seeing if there needs to be a shim fitted now that you have the shaft turning OK, clearly they are in there so that there is very little free movement for and aft in the tail shaft.

"Once you break something you will see how it was put together"
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by dellerie »

mike.perry wrote:Gold Seal means that it was factory rebuilt 30 years ago and has done 50,000 miles since so don't take the condition for granted
it was purchased from a member on here who assured me it came out of a car he broke up and was fine. no reason to not believe him. he offered me a no quibble refund if not.
dellerie
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by dellerie »

mike.perry wrote:Gold Seal means that it was factory rebuilt 30 years ago and has done 50,000 miles since so don't take the condition for granted
or it could have done 500 miles.
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Re: replacing 803 engine & Gearbox with 948 or 1098

Post by dellerie »

this comment has now been mentioned to me.

"Think you need to swap the reverse selector rod or you have no lift gate protecting reverse gear."

is this correct?
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