Gearbox mount for 1300 Marina

[listerjp2]

All, need some help. When I got my second kit the gearbox and engine was already in. The 'H' support for the gearbox should have been as stated in the manual i.e. the bottom of the 'H' should be flush with the floor. My one is between the 1800 fixing (legs of the 'H' protruding 25mm below floor line) and the 1300 as above. Can anyone tell me if this is going to affect the build/running of the car?

[lil_red_roadster]

Re: Gearbox mount for 1300 Marina

My 1800 H mount was always flush...and I can't recall any difference mentioned in the instructions (c 1985 kit)...are we talking a Marlin kit or YKC..?

[listerjp2]

Re: Gearbox mount for 1300 Marina

Hi Jez, It a Marlin kit 1984. I have two sets of instructions both say the legs of the H Mount should be flush. Fot the 1800 the legs should protrude by 25mm.

[listerjp2]

Re: Gearbox mount for 1300 Marina

All, Any pics from anyone on the gearbox mount would be useful. Many thanks. Remember mine is a 1300 Marina.

[lil_red_roadster]

Re: Gearbox mount for 1300 Marina

My kit also dates from 84 and the instructions simply state the bottom of the H mount should be flush. Nothing about differences between 1.3 & 1.8...maybe there were some minor tunnel/chassis changes around this point?

Providing everything lines up OK I don't see a problem, though poking the mount below the tunnel side does create a nice sharp obstacle to injure yourself on when fannying about under the car..and probably not ideal if trialling...

[listerjp2]

Re: Gearbox mount for 1300 Marina

Hi Jez, Find a copy of the page from the manual - Adrian

[listerjp2]

Re: Gearbox mount for 1300 Marina

Mmmmm - May have sussed it, the 1.8 SC is a taller unit with the single carb and therefore may need to set the gearbox lower. The question still stands that my H mount is between the 1.3 and the 1.8sc. Maybe I just leave it and see if anything happens out of the ordinary when its running. I don't reallly want to make more holes in the side of the transmision cover.

[dcunn]

Re: Gearbox mount for 1300 Marina

Adrian, hope you don't mind me butting in here. Looking at the pic you have posted it seems in far more detail than the .pdf copy I have downloaded from "t" site, so is yours a much later and better detailed manual ?

[listerjp2]

Re: Gearbox mount for 1300 Marina

Dave, yep I think you are right. This manual has a semi hard cover. Looking at it most of the previous hand written text is in type. It covers things like dash layout and carpet with pictures. Maybe I should copy this and send to Ty so that he can post it to web. Do you have any opinions on my problem with the gearbox H mount?

[dcunn]

Re: Gearbox mount for 1300 Marina

Adrian. I for one would like a copy ! If it's any help I'm retired so have the time available to scan. Tel me 01427 678084 if you want to talk about it.

Re your problem, sorry don't yet have an opinion. I only bought my car last month and don't know it well enough. My 1700 O type is attached to a Dolomite box, so probably different again !

I'm currently putting Superflex bushes into rear springs, and then front tie rods, then a timing belt change. This will complete a thorough check and service and give me the confidence to do some longer mileage trips. Hoping to do Derbys next month. Regards DC

[trevor_ford]

Re: Gearbox mount for 1300 Marina

Don't know if this helps, but when I changed from 1.3 Marina engine to 1.7 Ital, I changed the engine mounts but left the gearbox mount as it was. Doesn't seem to have caused any problems.

[stevejgreen]

Re: Gearbox mount for 1300 Marina

Hi all. Some thoughts on this one.
I have to start from a glorious assumtion that the engine angle is critical. I doubt if it is as the ride height of a standard Marina is quite adjustable on the torsion bars. I would guess however that the engine was designed to be horizontal.

As Adrian suggests, I recall reading somewhere, that there was a Marlin reccomendation to use slim Landrover engine mounts on Single carb engines to give a little more clearance between carb and bonnet. I do not recall if that was 1.8 or 1.3. That would drop the nose of the engine and mean that the gearbox should be dropped proportionally.

The gearboxes on the Marina 1.8 and 1.3 use the same bellhousing and gearbox casting and gearbox mount. If there is a difference between engine mount to crankshaft centre height on 1.8 and 1.3 this also will effect the gearbox\mountng height. As the gearbox mount height is the same 1.8 and 1.3 then I would suppose there is no difference in engine blocks apart from overall height etc to give the larger cc.

So I guess that the variation described in the manual is more to do with Single carb engines than with engine capacity.

I would have thought the other critical point would be the gearbox tailshaft height relative to the propshaft and the angle it follows to the diff.
The prop is quite short (700mm) abd the total suspension travel is around 125mm making quite a large angular change. I would be looking to set the gearbox to minimise the angle of the prop at extremes.

I hope my thoughts help.

[lil_red_roadster]

Re: Gearbox mount for 1300 Marina

Steve...IIRC the 1.8 engine, when installed in the Marina, went in nose up/tail down and the manifold "slopes" to compensate. So it "looks" level but isn't. In the Marlin with a flush H mount it was level, resulting in the need to slot the carb stud holes to achieve the right result (plus slimmer mounts as you say...though even with these the dashpot just scraped the bonnet..I have the scars!). So I guess the later recommendation to adjust the location of the H mount could also have been an attempt to offset these factors?

[stevejgreen]

Re: Gearbox mount for 1300 Marina

Thanks Jez but....
Perhaps clutching at straws and being a bit pedantic but here goes.
The front engine mount is pretty much at the front of the engine. The gearbox mount is about 975mm back from there.
The sensitive parts of the engine where bonnet conflict is possible is within the first 400mm of the engine so a 25mm drop at the gearbox end generates a max of 10mm drop at the back of the cylinder head relative to the front.
Thinner engine mounts, at the front, will have a significant effect.

So to modify my theory. Still in relation to single carb installations, it could well be that its as simple as if thinner engine mounts are used, drop the gearbox by 25mm. Standard engine mounts, leave as is but watch for carb/bonnet clash.

Either way, dropping the gearbox 25mm will make a minimal difference to the engine height, and I doubt, that it would make a great difference in oil pickup or other engine parameters.
So if anyone can come up with an angular design tolerance of the B series that considers all the possible forces and oil slop.....

This might be clearer on later build manuals.