13 replies to this topic

[cjhols]

Hi all,
Just wondering whether it was normal for the idler gear to wear the casing that it fits into or whether it needs a spacer of some description???
Thanks

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[The Principal]

you need shims like these http://www.minispare...|Back to search also you should measure the end float

This may help - http://www.minimania...mary-Gear-Train

[The Principal]

Found this at last -

[Pigeonto]

If it seems to you that there are no thrust washers/shims then they have probably welded themselves to the idler gear and the result is they spin continuously with the gear which then wears the casings

[icklemini]

idler thrusts have oil grooves on both sides....

[bmcecosse]

Yes - oil groove both sides - doesn't matter. Looks like it has been assembled too tight. The casing either needs to be replaced - or carefully machined and then thicker washers used.... What does the matching gearbox face look like ?

[Cooperman]

You need a minimum of 0.004" idler gear end float when you do a trial assembly. Then when finally tightened up, using the same gasket as used for the trial fit, this gap can reduce to 0.002" when finally tightened. Even when you have done this it is a good idea to 'feel the ability of the transfer gear to rotate freely before fitting the 'red' seal in the casing. If it feels a bit tight, then strip the transfer casing off and use a slightly thinner thrust pad on one side of the transfer gear.

[cjhols]

Hi I'm wondering whether it may be the primary gear end float is too big (.6 mm). Doesn't the sleeve in front of the primary gear stop the idler gear from moving out?

[Pigeonto]

Not sure what you mean by 'sleeve' but the answer is no anyway.At over .020" end float that primary gear crashes from one end to the other everytime you accelerate/decelerate so needs sorting. Have you determined if the washers on the idler are free?

[cjhols]

By sleeve I mean Flange in front of the primary gear. And I dont think the washers are free. Are these the ones with the obliques circle in the. for oil????

[Pigeonto]

Oh the thin ring. probably to do with oil control or something.Yes the washers are about 1/8" thick with an eccentric groove They are on in the pictures

[Cooperman]

I think there is some confusion here. The primary gear has no effect on the transfer gear end float, but the primary gear should have no more than a0.008" end float and the transfer gear should have no more than 0.006" end float.
Now, to check the transfer gear end float you fit the transfer gear and transfer gear case to the gearbox, without the engine on the gearbox, and 'nip' it up with the new gasket fitted to the transfer gear case. This is called a 'trial build'. You can then measure the end float of the transfer gear and fit thicker or thinner thrust washers as necessary. Then remove the transfer gear case keeping the same gasket as some can be a different thickness. Never use grey coloured ones - the only ones to use are the pink-ish coloured ones. The grey ones can be too thin and are rubbish.
Once the transfer gear float is correct you fit the engine onto the gearbox and check the end float of the primary gear. the primary gear end float is determined by the inner thrust washer which is quite thin and has a chamfer on the inside diameter which sits towards the engine. If the end float is too much you mmeasure what you have and work out what you need then order a thicker inner thrust washer of the desired thickness. The primary gear is located by an outer thrust pad and a 'C'-washer. It is important to fit the C-washer downwards with the engine at TDC on pistons 1 & 4.
You have to measure everything, work out what you need and then order the correct thickness parts to achieve end floats which are within the limits stated.

[Pigeonto]

There is, or was Peter as the OP thought that the thin ring made onto the primary gear has some effect on the idler gear but i tried to explain that I think it has something to do with keeping the oil back a bit or something but it's irrelevent really.I have had the idler gear shims weld themselves to the idler gear( can I be the only one? haha), and it appears this has happened here too.He certainly needs to take very close notice of all you are telling him about setting the endfloats once he is ready to re-build

[Cooperman]

I've not had the transfer gear shims 'self-weld' to the gear, but I've heard of it when a 'cheapie' grey gasket was fitted without the end float being properly checked and set. Of course, if the transfer case has to come off without the engine coming off the box it is more difficult to check the end float, but the thing to do then is to remove the 'red' seal, fit the transfer case with a gasket of the right quality (= the right thickness) and with the primary gear removed and then see if the transfer gear rotates by feeling the top of it through the gap where the 'red' seal and primary gear goes. You can't actually measure the float easily, but you can confirm that it does rotate freely. Then you re-fit the primary gear and put in a new 'red' seal using the correct tool or by masking the primary gear splines with duct tape to prevent damage to the seal lip.