Bellhousing help

[Seriestwo]

I have recently purchased a gearbox (Thanks Bruce) from a series 3, and am in the process of installing it into my brothers series 2a which had syncro box in to start with. The issue is that they seem to be two differnt types of bell housing, and in turn 2 different clutch setups. I have measured up the bolt holes on the and they appear to be the same so it should fit, but what I am wondering is will the clutch master cylinder work with the different slave cylinder setup and will throwout bearing types be interchangable with each other.

Here are some pics of them. The one on the metal tray is the new one and the one on the wooden table is the old one.

Thanks
Chris

[Dinty]

G'day All, They are interchangeable, I have a S3 box in my S2A, I retained the S2A clutch mech, (i.e. complete swapover of the bellhousing) it is a simple enough job cheers Dennis:angel:
there are differences between 6cyl & 4cyl bell housing, the studs are in a different position, not sure whether it's a tad smaller, but anyway the front part of the g/box is basically universal between S2/S3 hope thats of some help

[Lotz-A-Landies]

OK that's simple, the new one has the SIII clutch and bell housing and the old one has the series 2a bell housing and clutch.

The bell housings and clutch systems are interchangeable onto the SIII gearbox housing.

You now have 2 options. Swap bell housings or get a SIII clutch pipe.

Diana

[Seriestwo]

Thanks for your advise. I will just leave the bell housing on the gearbox and it also came with the series 3 clutch pipe so I think we will just do it that way.

Thanks again.
Chris

[isuzurover]

NB!!!

The pressure plates are different between a Series 3 and a IIA.

The IIA pressure plate has a big ring in the middle to mate with the throwout "flange". Whereas the throwout bearing on the SIII mates directly with the fingers on the SIII pressure plate.

You must have a IIa pressure plate. If you fit the SIII box with a IIA pp, you will most likely have no drive as the clutch willl be permanently engaged.

I know this because my father's IIA had a SIII pressure plate and IIA box fitted when we bought it (as a half finished project). The PO wondered why the clutch did not disengage. I had to machine a 15(ish) mm spacer and clamp it to the throwout flange on the IIA box to get it to work.

You would have the opposite problem, the throwout bearing and the pressure plate would likely be in permanent contact.

EDIT - I think that fitting a IIA bellhousing to a SIII box may change the ratios slightly, as the input gear tooth counts are different between the 2 boxes. Not 100% sure on this though, as I was told this, but never bothered to count the teeth myself.

[Aaron IIA]

I don't know about SIII pressure plates, but SIIA had a three lever pressure plate for the petrol, and diaphragm pressure plate for the diesel. The original diaphragm pressure plate did have a spacer formed onto it, where it contacted the throw out mechanism. My after-market pressure plate was missing this spacer, and as was previously mentioned this made it difficult to disengage the clutch when a new friction plate was fitted. When the friction plate was worn in a little bit, the clutch did operate properly. I did have to spend a bit of time adjusting the torque rod connecting to the slave cylinder, making a new connector that no longer had the clevice pins at ninety degrees to each other. It now works well and you would never know that the spacer was not on the pressure plate. When I next change the friction plate, I will probably make a new, longer, throwout mechanism.

Aaron.

[JDNSW]

I don't know about SIII pressure plates, but SIIA had a three lever pressure plate for the petrol, and diaphragm pressure plate for the diesel. ......

Aaron.

Not quite that simple! The petrol engine had a conventional clutch (three lever, coil springs) for petrol engines, except North America. The diesel was similar up to engine suffix J, when they went to a diaphragm type clutch. The diaphragm clutch was optional on earlier diesels and petrol outsid NA. And, of course, many have been updated with the Series 3 type clutch. But as pointed out, the proper S2a diaphragm type pressure plate has a ring on it to act as a spacer. (from parts book)

John

[isuzurover]

And, of course, many have been updated with the Series 3 type clutch. But as pointed out, the proper S2a diaphragm type pressure plate has a ring on it to act as a spacer. (from parts book)

John

JD - I think you need to change "clutch" to "pressure plate" in most of that paragraph. The clutch plates are the same, the pressure plates are different.

I am not sure how people are saying they can use SIII pressure plates with IIA boxes (clutch mechanisms). There was no way we could even get the throwout mechanism to contact the diaphram of the SIII pressure plate on dad's IIA.

[Blknight.aus]

theres a spacer available to let you do it.

[JDNSW]

JD - I think you need to change "clutch" to "pressure plate" in most of that paragraph. The clutch plates are the same, the pressure plates are different.

Yes, of course.

I am not sure how people are saying they can use SIII pressure plates with IIA boxes (clutch mechanisms). There was no way we could even get the throwout mechanism to contact the diaphram of the SIII pressure plate on dad's IIA.

As noted the proper S2a diaphragm pressure plate has a spacer attached to it. Aaron II notes what he had to do to get it to work without one. I think I would be making a spacer to attach to the withdrawal sleeve if I had to do it.

John

[Lotz-A-Landies]

I guess the solution to all this is to use the SIII pressure plate with the SIII throw out and the SIIa 3 finger type on the SIIa.

However I seem to remember that the difference between the 3 finger type and the diaphragm type is not anything to do with spacers but that the diaphragm type is for a 9 1/2" pressure plate while the 3 fingers are for the 8" (or 9" no books at work) and the spacing for the throw-out sleeve is the same whatever pressure plate and throw-out you use.

Diana

[isuzurover]

I think I would be making a spacer to attach to the withdrawal sleeve if I had to do it.

John

As I said in my first post, that is what I did on my dad's IIA.

I bought some 4340 of the appropriate size (actually the steel place gave me an end offcut for free). Machined it to the same curved profile as a SIII throwout bearing, drilled and tapped it to take bolts and 3 l-shaped brackets to attach it to the flange on the IIA throwout flange. Then I hardened and tempered it.

It has been working fine since 1997. I suspect it has work a bit, as the clutch linkage needed adjusting once, but it is still hanging in there.

IRC it was about 16.5mm thick. We had a IIA and SIII gearbox side by side so I just measured the difference.




However I seem to remember that the difference between the 3 finger type and the diaphragm type is not anything to do with spacers but that the diaphragm type is for a 9 1/2" pressure plate while the 3 fingers are for the 8" (or 9" no books at work) and the spacing for the throw-out sleeve is the same whatever pressure plate and throw-out you use.

Diana

Yes and no. The SII/A/III were fitted with 9" and 9.5" clutches. 9" went in the petrols, and 9.5" in the diesel and one-ton models.

The SIIA 9" pressure plate was the 3 finger type.
https://www.aulro.com/afvb/images/imported/2009/05/467.jpg

The IIA 9.5" pressure plate had a disc in the middle:
https://www.aulro.com/afvb/images/imported/2009/05/468.jpg

The SIII 9.5" (and 9" if used?) had no disc - basically identical to above, but the lack of disc means the clutch mechanism either needs 16mm extra travel or must be 16mm closer to the pressure plate.