Gearbox swop?

[billwill]

Saw-able nuts were on hand, half-nuts were not.

[alexblack13]

LOL.... OK.

AB

[bcmc33]

Graham said that the std spigot bush is fine and also so is the clutch fork (with slight mod). He said its an easy job in fact..


Where have I heard that before?

Alex,

I am not sure what Graham means by the spigot bush - is it what Brian Buckland calls a bearing housing? If it is, then the 5 speed release bearing won't fit. I'll explain:

The 4 speed bearing has a bore of 1.375" diameter and the 5 speed bearing is 1.5" diameter. The bearing is a light force fit onto a 2.5mm wide shoulder on the housing.
You will need to make a sleeve to fit the bearing onto the shoulder. With your skills and equipment - that should pose no problem.

The remainder of the 4 speed lever system will be OK for the 5 speed.

[paddy]

I understood the spigot bush to be the bush that fits in the end of the crankshaft that locates the end of the gearbox input shaft.

Paddy

[bcmc33]

I understood the spigot bush to be the bush that fits in the end of the crankshaft that locates the end of the gearbox input shaft.

Paddy

Your quite correct, Paddy - I read Graham's message wrongly - never mind how careful I try to be, occasionally the dyslexia still gets in the way.

[alexblack13]

Thanks guys. Yes Brian I know I need the release bearing and its holder for the 5 speed. The 4 speed lever / fork will fit with a small mod. Slave is the same. SO... The spigot bearing in the flywheel / box input shaft needle roller bearing ... Does it need a special carrier? is it a different bearing? or what? Graham says its exactly the same and I am inclined to believe him. I will soon find out. I'm not rushing this... I won't you hear!! I might just get stuck in soon though. OK I will start this weekend.



I need to get the sump off to take down to the NEC... Brian has his mitts on it...

I have a complete clutch ass'y including bearing (and holder) on Order with Susan M.... Great lass !! And I have a propshaft from Aussie John... Thanks bud.

Ready to rock. I will take care of a couple of niggles when the engine is out. ...

[bcmc33]

Alex,

The 5 speed bearing is very different from the 4 speed bearing. The 5 speed bearing acts directly on the diaphragm springs and not on a fixed pad as per the 4 speed.

The spigot bearing is standard. However, the 5 speed spigot end point is some 12mm shorter than that of the 4 speed. I compromised and installed the bearing 5mm short of full insertion in the crank.

[NickD]

The Lotus 5-speed gearbox does use the same spigot bearing as the 4-speed. However, it is not fitted into the end of the crankshaft but is instead mounted in a bush pressed into the centre of the flywheel. This moves the spigot nearer to the gearbox as the 5-speed input shaft is shorter than the 4-speed version

[alexblack13]

That's what I thought! But Graham says not required.. I can't see how it is not needed so.. Anyone got the details of the said ''carrier'' for the spigot in this case.

I will make a few more enquiries...

Al'

[elans4dhc]

Alex,

I can show you the spigot bearing carrier if you drop by my house in NQ. It won't be difficult to make a replica.

Andrew

[bcmc33]

That's what I thought! But Graham says not required.. I can't see how it is not needed so.. Anyone got the details of the said ''carrier'' for the spigot in this case.

As I remember the 4 speed spigot has 20mm engagement into the crank needle bearing. As the 5 speed is 12mm shorter in length, the engagement would be 8mm with the bearing fully engaged in the crank.
8mm engagement is probably OK for the purpose, but I chose to fit the 22mm long bearing 5mm short of full engagement in the crank to give a 13mm spigot engagement - more that adequate for the purpose.

I too would like to see what a carrier looks like.

[elans4dhc]

Brian,

This is what the spigot bearing carrier looks like - it is a interference fit into the centre of the flywheel.

Andrew

[elans4dhc]

Brian,

I did attach a photograph of the carrier but it seems to have drifted off somewhere - sorry!

Andrew

[alexblack13]

Andrew..Check your PM's

I want to visit /looksee/measure etc.. I have some Phos/bronze bar. What say you (all) to making if from that and doing away with the roller bearing? Quite a few cars just had ''oilite'' (phos' bronze) bushes/bearings fitted.

Next question... Is it worth having the flywheel and clutch ass'y balanced. Not sure if I want to take out the crank.

Job is started to.... Roll bar off. X member off. starter off. Sump off (Brian!) No wear products anywhere and engine bottom end inside looks like new...

Next question.. Who makes the best sump gasket sets? what do you (all ) recommend?

AB..

[alexblack13]

When can I visit Andrew?

Alex..