Engine/gearbox alignment FH

[Martin K]

Hi again

Things are moving along, but I’ve got a slight (major?) problem.

I’ve attached two photos. One shows the zero space between the FERC, primary chain case, gearbox and engine plates (ie no room for adjustment), the second shows the 1mm gap between the chain case and the drive side of the engine.

It seems to me that the engine and gearbox are out of alignment and the primary chain case simply can’t flex to take up that gap (I have no intention of forcing it!).

Any ideas, learned gents?

Should I loosen all the engine, gearbox, engine plate bolts and give the whole thing a good shake so it finds it’s own best fit, or have I fundamentally messed this up by - I don’t know - bolting it all together wrong?

All spacers, washers, bolts, brackets are exactly as I took them off, it just doesn’t sit together nicely now.

Having fitted the clutch temporarily (no oil yet in the chain case) when I gently kick it over, all is well, except I can ‘feel/hear’ the clutch still gently catching on the primary case as it turns - another indicator that all is not well. Oil might make it quieter, but it shouldn’t rub and (Paul - your picture of the FERC spacer you made refers) you’ll see there isn’t any room in there for that so my FH is clearly differently aligned to yours! It’s all bolted behind and to the frame correctly so should have all pulled into place. Infuriating - and may be easily remedied. That’s the hope!

All help appreciated.

Martin

[simon.holyfield]

Does the inner primary pull up to the crankcase when the FERC is not fitted, and without the rear end bolted to the frame?

[Mick D]

Hi Martin

If I were you I'd concentrate my efforts to discovering why you have a 1mm gap between the crank case a PCC inner, there should be no gap there, fix that before you worry about any clutch clearance.

I would also fit the battery carrier, (it attaches to the PCC inner), before assessing the clutch clearance.

Finally, your FERC forward attachment does not appear to align with the inner PCC, a spacer and a bit of bending would improve this.

Where have you elected to place the clutch centre thrust washers and how many?

Regards Mick

[Martin K]

Hi Mick, Simon

I think the challenge is simply no space between PCC, FERC and gearbox nut/bolt. So (in reverse order) the nut/bolt touches the FERC, the FEEC pushes the PCC outwards - the whole lot then ‘misses’ the drive side of the engine.

When I put the outer PCC on and bolt it up, it simply levers the front away from the engine.

I’ll take it all off again and try to realign, but I can’t figure out how to create space from that gearbox nut/bolt combo outwards.

I haven’t tried it all without the FERC. I can’t bring myself to dismantle that much of it again .

Mick you mentioned that the front fitting looks out of line? Can you explain more? It seems to fit and bolt to the rear of the PCC inner ok.

I went with thrust washers as per your note and drags piccie - one against the gearbox output shaft, one after the clutch outer basket, before the locknut (by the way - any torque guide for that clutch centre nut please?)

Cheers

[Simon.Gardiner]

The ultimate check for alignment is across the sprockets - take the chaincase outer off, fit the shock absorber assembly/engine sprocket (only needs to be 'firm') and check against the chainwheel (fiddly 'cos the chainwheel will want to wander about, but should be possible with care - and also needs the chainwheel not to be in contact with the chaincase inner and to have correct spacing on the gearbox mainshaft.... )

Effectively, the thrust washers need to be either side of the brass cage that retains the chainwheel needle-rollers.

Mine's a very tight fit around the gearbox/FERC area as well. You might need to really 'go hard' on the components that you've got there. From what I can see in the pic it's the top gearbox stud that is pushing on the FERC, slacken things off until the FERC is up against the nut. To try and work out what's going on you might also need to take the washer out - and check to see if another nut is slightly thinner than the one you've used.

At this point I'd concentrate on getting the primary chaincase inner properly in place (against the crankcase and the frame at the lower rear mounting point and without any contact from the chainwheel). You can do that well enough using its single screw into the crankcase at the front and (eg) a suitably sized nut (or two) as spacers to stand in for the outer primary case at the rear mounting. You'll be able to see if it's fitting on the crankcase properly even with the single screw in place.

As someone who spent days trying to solve the new rubbing-noises I got after taking out the VH and putting in the FH engine and chaincase, 'these are the joys'.....

HTH

SG

[Mick D]

Hi Martin

I removed the washer on the gearbox top stud to give me a bit more clearance:

FERC Clearance.png (265.52 KiB) Viewed 680 times

You need to work from the front backwards

Regards Mick

RE the FERC fwd mount, the tab holding the anchor nut isn't parallel to the boss on the PCC inner, I'd sort that and shim accordingly

[Roger Gwynn]

Do you have the correct inner chaincase, it should have casting number K400 and be .775" thick at the front where it bolts to the c/case? The very similar KH one uses the same casting, K400, but is .625" thick. The singles ones are quite different with casting E9/3436. All these components have very little space between them so a little misalignment or incorrect parts can cause a lot of trouble.

[paul.jameson]

To tell whether you have a KH or FH primary inner, take off the battery platform and look at the mounting holes in the top of the chaincase inner. They are stamped KH and FH on the bosses for identification purposes.

[Martin K]

Hi Roger

Many thanks - checked and I have the k400 case and the outer is stamped E9/3001

I’ll start at the front and line it up, with the inner PCC meeting the frame at the base/back end as suggested by Mick and Simon.

I’m sure some judicious wiggling and jiggling will eek out a mm or so clearance - eventually!

Cheers

Martin

[Mick D]

Hi Martin

The inner PCC identification that Paul refers to is visible in this photo:

PCC FH.png (318.9 KiB) Viewed 635 times

My outer case is also identified by E9/3001 cast in.

I recorded the torques I applied as:

Cush drive - 52 Lbs f Ft
Clutch centre - 60 Lbs f Ft
Clutch basket - 10 Lbs f Ft

I can't remember if I found any of these figures in either Ariel or BSA documentation or just applied my opinion of 'best estimate'

Regards Mick