Engine in bits for a rebore-anything else worth doing?

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ndevans
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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

It's an ex-Marina engine, but it didn't come straight out of a Marina. I bought it second hand-maybe it's been used in a Minor or Midget before?
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
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philthehill
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Re: Engine in bits for a rebore-anything else worth doing?

Post by philthehill »

Thank you for the above.

That may explain why it has the solid oilite bush fitted.

Though it should be borne in mind that early Marinas had a solid oilite bush which was superseded by the needle bearing at some point.

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ndevans
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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

Ah well, it may be original then, the engine serial number dates it to around 1978. I've squirted some oil in there.
The gearbox 1st motion shaft is polished nicely, after 3000 miles in the engine before I lifted it, but not what I'd call worn.
cheers N

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midget
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Re: Engine in bits for a rebore-anything else worth doing?

Post by midget »

Just my two p'nth, but after almost completing this conversion and had similar problems :cry: , I am hoping that the bush (resized ESM article} is fitted to the FLYWHEEL to carry the first motion shaft of the Minor box ,as there is no way in the world that the Minor shaft will ever reach the Crankshaft to locate in any bush.
If you observe my pictures in my similar thread, the Marina shaft is much longer than the Minor.
My engine and box are now successfully mated but not fitted to car until after the National, so unable to say if it is 100% correct?
John
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ndevans
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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

I'm not in a position to check, but the gearbox 1st motion shaft on my box (1098 ribbed box) slightly protrudes past the bellhousing mating flange. As this mates up with the engine backplate, that must mean the 1st motion shaft goes right through the flywheel, and at least partly into the crankshaft flange.
I can't measure it until tonight, but I will, and as I say above, the 1st motion shaft has a clear polished area about 1/2" long at the end.

Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
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ndevans
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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

The Minor 1st motion shaft protrudes past the bellhousing flange by about 3mm, so it goes all the way through the flywheel, into the crankshaft flange, into the crankshaft itself and finishes about 5mm short of the end of the hollow in the crankshaft, which is well past the bush.

Engine now reunited with gearbox, I've spent this evening dry rehearsing getting it back in. I have a chain hoist in the garage, suspended from a strong wooden beam. I've got the floor and gearbox cross member removed, and the extension fitted to the gearbox, but not the remote control.
I'm going to position the engine on supports, so that the sump is just above the front engine bay floor. I'm then going to move the car to just in front of the engine, raise the engine, push the car under and tilt/lower the engine so the gearbox extension goes under the steering rack.
Once the sump is over the front cross member, I'm going to lower the engine, support the gearbox, reconnect the front mounting legs, then reattach the gearbox cross member.

In other news, I now understand why the old gearbox bellhousing broke at the top when I removed it. The lug on the 1275 block is slightly too big for the centre hole in the 1098 bellhousing. As I mated it to the engine, I couldn't get it on, and had to file the hole out. I suspect that when I put it on last time, the lug caused the bellhousing to crack, and when I took it off, it just broke off.

Never a dull moment!
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
midget
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Re: Engine in bits for a rebore-anything else worth doing?

Post by midget »

Interesting. Can I ask where did you source your crankshaft bush from please, and have you had this modified?
John
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ndevans
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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

midget wrote: Tue Jun 18, 2019 7:32 am Interesting. Can I ask where did you source your crankshaft bush from please, and have you had this modified?
I didn't, it was already in the crankshaft. It's an ex-Marina engine, it may have been used in a Minor before I got it.
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
oliver90owner
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Re: Engine in bits for a rebore-anything else worth doing?

Post by oliver90owner »

I'm then going to move the car to just in front of the engine, raise the engine, push the car under and tilt/lower the engine so the gearbox extension goes under the steering rack.

Far better if you position the car behind the engine. :D :D

Might be OK for Volkswagen beetle, but not a Moggie Minor! :D :D
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Re: Engine in bits for a rebore-anything else worth doing?

Post by panky »

ndevans wrote: Sat Jun 15, 2019 10:56 pm Got the sump, timing cover, backplate and head on now. Got the flywheel on as well, but having a job tightening up the bolts to 40lbft without the crankshaft turning.
An old main bearing shell does the trick too. The ends of the shell fit nicely into the teeth on the flywheel and the curved back of the shell fits against the inside of the starter motor hole so it feels very secure but easy to fit and remove.
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ndevans
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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

Well it was a bit of a struggle, but with a bit of patience we got it back in, as described above. Only slight hitch was that the heater tap got caught on the battery tray, and the arm twisted off. Probably not irreparable.
Lots of bolts to do up now, annoyingly one of the captive nuts in the chassis rail that holds the crossmember in has worked loose and spins in its cage. As it's under the brake master cylinder, I'm going to leave it for now.
The newly rebuilt gearbox is a bit of a worry-its very fiddly and tricky selecting gears. All 5 can be selected, but only after a lot of fiddling with the gear lever. However, I managed to leave out the spring that sits under the gear lever when I refitted the remote control, so maybe that's the reason. If not, I reckon it could be the interlock balls that need a little more oil (they were assembled with oil), or the selector rod may need adjustment or tightening.
Progress though, but I feel that going to the National Rally in it may be slightly optimistic!
Cheers N
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IMG_20190619_000945~2.jpg (2.05 MiB) Viewed 1775 times
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
philthehill
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Re: Engine in bits for a rebore-anything else worth doing?

Post by philthehill »

Regarding the location dowel at the top rear of the block:-

I have at least four different types and sizes of dowel including stepped dowels all of which have been removed from 'A' series engine blocks.

It is most important that the hole in the rear engine plate and the hole in the gearbox bell housing are the right size otherwise as already found the dowel will not go through the rear engine plate or more damaging the gearbox bell housing.

The Pt No: of the Marina top dowel is 12G3491 for the 1275cc engine. The dowel is stepped.

The Pt No: of the MG Midget 1275cc top dowel is 12G422 (MOSS).

A tip for enlarging the hole without drilling:-

Find a round file of the same diameter as the required hole and which has a tapered opposite end to the handle. Insert into the hole and keeping the file square to the face (of the bell housing) rotate the file anti-clockwise. The hole will be enlarged with the hole being kept round.
Reciprocating filing or drilling the hole to enlarge can make the hole wander off centre with disastrous results. :cry:

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ndevans
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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

I have a small round file, I managed to take enough metal off for the dowel to fit, and it's still round enough. I guess the function of the dowel is to locate the box centre properly wrt the crankshaft, so it's not off centre.

Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
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philthehill
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Re: Engine in bits for a rebore-anything else worth doing?

Post by philthehill »

The dowel is also there to locate, secure and to eliminate any movement between the engine, rear engine plate and gearbox bell housing.

It must be remembered that there are two dowels on the rear of the engine block to locate the block, plate and bell housing. Any misalignment of one will effect the other.

The 5/16" UNF bolts cannot be relied on to locate and hold the block, plate and gearbox housing against movement.

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ndevans
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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

Noted, thanks. It's all on ok now.

Hopefully I've found the problem with the gearbox being fiddly.
The spring that sits under the gear lever, in the metal cup, was missing. I've found it-but annoyingly, I can't find the nylon bush that sits between the spring and gear lever. When I took it apart, I heard something drop, and found the spring. The nylon bush must have gone into orbit at the same time. Can't find it anywhere.

No point in rushing now, it's not going to be ready for the national.

Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
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ndevans
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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

Ok, had a week and a bit off. Wasn't well last week, but I'm back in business now.

The engine and gearbox are in, with the nuts on the 4 rubber mounts done up loosely. Is there any order in which I need to do them up, to keep the engine fairly central? I did one of the gearbox mounts up, but it seems to have pulled the box off centre slightly, so I slackened off again. If I just tighten up the nuts on the other side, will it equalise?

Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
philthehill
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Re: Engine in bits for a rebore-anything else worth doing?

Post by philthehill »

There should be no problems with the engine/gearbox mounts. No order of tightening required. Tighten progressively if that will help.

Make sure that the gearbox mounts and brackets are the right way round.

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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

Think I've got everything right-the gearbox brackets are on with the longer side facing the rear of the car. I think the rubber mounts will only go on one way.

Cylinder head now torqued, but my Haynes Marina manual says 40ftlb for pre-1975, 50ftlb thereafter. Not sure how to date my engine-i think I dated it to about 1978, but can't find the website I used now. It's an A series, not an A+.

The threaded insert in the oil filter mount on the block has come out, and I can't remember which way round out went into the block- is it the long thread into the block?

Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
philthehill
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Re: Engine in bits for a rebore-anything else worth doing?

Post by philthehill »

If your cylinder head studs have a top taper, a centre pop or letter stamped on the top of the studs they are torqued to 50 ft lbf.
When setting to that torque the flanged nuts must be used.

Not sure what insert you have but the inserts I have are fully threaded which means that the insert for securing the filter can be screwed in too far. I use Loctite to secure the insert in the block so that the threads are 50/50 into block and filter.

There is only one insert/adapter listed in the BL Marina parts list and it is Pt No: 12G2518.

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Re: Engine in bits for a rebore-anything else worth doing?

Post by ndevans »

I'm not sure what the studs were, as they've all been replaced. The nuts are not flanged, so I've gone with 40ft-lb.
I've screwed the filter thread in long thread down, the filter goes on fine.
Hopefully I'll get it running today, it's just the fiddly bits now, like the exhaust and so on. Unfortunately the plastic 7 blade doesn't clear the radiator, so I've reused the original 2-blade fan.
I can't use my HIF44 carb and Minisport manifold, as the filter casing (off a Mini) does not clear the vacuum take off, or the fuel pipe to the pump. I'll have to rethink that, and find another filter casing-until then, it's back to the HIF38 & Howley manifold.

Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
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