Austin Somerset fast idle

[widd0wss0n]

Was taking my somerset out the other day and all of a sudden there was a noise from the gearbox which sounded like gravel being flung into a tin can, that was just for a second or two but now it has a constant rattle coming from the gear box and the engine is idling quickly. I can remove the idle screw on the carb and it still idles quickly. Does anyone have any ideas?

Thanks

Dave

[number5]

Hi Dave–In both A70’s and 90’s I have owned, with the breaking of a tooth, or teeth, there has never been any rattling. My first inclination is that it sounds a bit like a collapsing clutch plate. After the “happening”, were you able to change gears normally.
Regards-Peter.

[widd0wss0n]

Hi Peter,

Thanks for your reply.

Gear selection has never been smooth since I got the car, I have only done about 100 miles in it since I bought it, all testing miles. Reverse has always been a pig to get into, taking several attempts of falling into second before I get reverse, first was a little sticky, however when running the selection of higher gears was ok. After this happened I was putting it in and out of gear and First\second were stickier than normal. I also got stuck in reverse and it was not easy to get it back out again. The rattle does sound like its in the bell housing area. I also noticed that the clutch pedal adjustment rod is bent, could this have contributed to a clutch plate failing?

Dave

[number5]

Dave-It does seem like the box will need to be removed. As for the gear changing, from your description it would seem to me that the cable from the steering column post to the gearbox lever on the underside of the box has been causing some of your problems. I think your A40 has the same set-up as the A70’s and 90’s.

Your description of reverse problems indicates that the cable is a significant part of your problem. The cables can stretch, and although an adjustment might only require taking up slack as little as 1/32 inch to get the selector back where it belongs, because the clamping fixture on the lower lever can, and does distort the cable, it can be an awkward and time consuming job to get it right. Perhaps the Counties Spares might have a new one, or can advise where you can get one.

When you get the box out to do the clutch, remember to take off the side cover to be able to check the gear teeth. Don’t lose the thrust spring of the cross shaft as you lift the cover off. Using a good torch. you should be able to visually check each cog to see if there are any chipped or missing teeth. Although a little hard to view each some clearly, each can be view sufficiently to check their condition.

Cheers-Peter

[widd0wss0n]

Thanks peter, I’ve ordered a new cable and clutch etc from the counties spares. Hopefully that will solve the problem.

Dave

[number5]

‘Evening Dave,
Should have mentioned that when fitting a new clutch, there may also be a problem with the pressure plate, in that its springs may be the problem.

In addition, if your own pressure plate is still OK springwise, because of possibility that a worn clutch plate rivets could have scored its surface. These rivets can also do the same to the flywheel face, and it too may need grinding.

Another thing to look carefully at is the flywheel surface. Although it may be still quite smooth an not affected rivets etc, it can develop hair line cracks that can nearly be invisible to the naked eye, with the heat of use, can open up and start to shave the lining of the clutch plate. With A70’s and 90’s, I have experienced these cracks that a 0.005 feeler gauge can be inserted into. Such though, to my experience, is more attune to a vehicle used in heavy traffic, where the possibility of riding the clutch is more likely to occur. With my A90 coupe, over 150,000 miles were done in peak hour driving, and in another A90 convertible, over 250,000 miles in the same type of traffic conditions.

If I can assist in any way, let me know.

Regards-Peter.

[widd0wss0n]

Thanks for your help Peter. I’ve just changed the clutch, one of the springs had come out the pressure plate, plate was different in that it only had four springs so maybe some aftermarket variety. Next problem is now when I push the clutch pedal I get a grinding noise and the clutch doesn’t work. Any ideas? I’m not sure of I’ve maybe not adjusted the clutch pedal adjustment rod properly or if it’s something to do with the release bearing. I changed the plate, housing and bearing with ones from club spares and I’m positive the plate was fitted the correct way round.

Any help would be greatly appreciated, I’ve got a show in a few weeks and I don’t want to miss it.

Dave

[number5]

Dave-Hi,

Sorry about your continuing woes. From memory, the raised centre section of the clutch plate faces towards the gearbox. In around the other way, it would be ni on impossible to engage it.

Also, is yours an hydraulic pedal movement, or mechanical linkage. With the A70/90, which has a carbon thrust bearing, the gap should not exceed 1/16 inch. Can you say what freeplay gap youset the adjustment at. Not ever having owned any Austins with hydraulic operation for the clutch, I am not sure how they set the freeplay gap. Are you able to send me the manual notes on this. My e-mail is pjhackney@optus.net.au

In your note, you mentioned changing the plate, housing and bearing. I presume the housing means the pressure plate.

Cheers—hear from you soon.

Peter.

[widd0wss0n]

Hi Peter,
When I said the housing I was meaning the clutch cover assembly that bolts to the fly wheel.

I am sure I put the raised center section of the clutch plate towards the gearbox, I remember checking it to make sure, the raised section fits into the cover assembly and stops the plate sliding about too much. Wish I had taken a picture before I fitted it now just to be 100% sure, I’m doubting myself now.

The Somerset has a mechanical linkage and a carbon thrust bearing, this is where I am not sure if I have set the clearance correctly and if incorrect setting of the clearance would be causing my problem. At the moment the pedal is near the floor before it starts grinding and I feel feedback through the pedal. Is the thrust bearing maybe just touching the release leaver plate on the cover assembly but not releasing the clutch plate? So the thrust bearing is just sitting on the release plate white the cover assembly turns.

Should I remove the clutch pedal spring to set the clearance? What is the best way to set the clearance? I was having difficulty telling when I was feeling the resistance of the clutch springs. I have emailed you the manual, page 93 (Section E/1) under running adjustments explains the clearance I think it’s the same as the A70/90.

Could the thrust\release bearing not moving properly be causing the problem, was I supposed to put a little bit of grease at each side of the bearing where it fits into the forks so it moves smoothly?

Thanks for your help peter.

Dave

[widd0wss0n]

Hi Peter,

Tried to email you but your email system rejected my email for security reasons. Here is the extract from the manual.

Running Adjustments
The only necessary adjustment is to restore the
free movement of the clutch pedal (i.e. movement of
the pedal before the release bearing comes into contact
with the release lever plate and commences to withdraw
the clutch). As the driven plate linings wear, the free
movement of the pedal will gradually decrease, thus
tending to prevent the clutch fully engaging and permitting
too great a movement on withdrawal. This free
movement must be maintained at the correct amount,
which is approximately 3/4-in. (19. 05 mm.).
Adjustment is made by altering the effective length
of the rod between pedal and clutch operating lever or
the clutch shaft end (see Figs. I and 4). To increase
the movement first slacken the locknut and screw out
the adjusting rod by means of its hexagon head. Finally
tighten the locknut.
In all cases adjustment must be such as to allow
this free movement to be felt by the pressure of one
finger on the clutch pedal.
To ascertain the amount of free movement, depress
the pedal until the resistance of the clutch springs is felt.
The 3/4-in. (19. 05 mm.) of free movement in the
pedal will give a minimum clearance of 3/32 – 1/8-in. (2. 38-
3.17 mm.) between the graphite release bearing and the
release lever plate, thus preventing continual rubbing of
the release bearing on the plate.

[widd0wss0n]

Removed my gearbox again today and it turns out the fork that holds the clutch release bearing is rubbing on the clutch cover assembly. Think the cover assembly has not been gauged property or is faulty.

[number5]

Hi there Dave,
Just wondering how you are progressing with your clutch problem. I did send you another note to your mailbox, though not sure if it reached you. Try sending another one here to see if it transmits OK.
Cheers-Peter.

[number5]

Hi there Dave,
Hope you have resolved your clutch problem, and what the actual cause was.
Regards-Peter.

[widd0wss0n]

Hi Peter,
Sorry I did not get the notes you sent to my mailbox.

I had another new clutch kit sent up from club spares and fitted it on Saturday, clutch is working fine now. Just can’t get it into reverse gear, think that is a problem with the linkage because the selector cable seems to be tight. I did get it into reverse once but then the gear leaver was stuck in reverse, I had to lift the C leaver under the bonnet to release the gear leaver.

My original problem of the rattle in the bell housing was caused by a spring coming out of the clutch plate, the fast idle is an unrelated issue, think it may be the head bolts needing tightened after a recent cylinder head gasket change.

Second problem, after fitting the first new clutch, was the release leaver plate on the clutch assembly was too low resulting in the release bearing fork rubbing against the clutch assembly when the clutch pedal was fully depressed. I compared the newest clutch assembly to the first one I was sent and the release leaver plate was about 13mm higher on the newest one. The first one was reconditioned by the looks of it and must not have been gauged\adjusted properly.

Thanks for all your help. I didn’t have a clue about gearbox\clutch at the start, hence some silly questions and stabbing in the dark, however I feel like a veteran now lol.

Dave

[number5]

Hi Dave,
Glad to read that your clutch problems are resolved.

How did you go though with the gear selection? This is often caused by the stretching of the cable, and may just need a minor adjustment of the length on the lower selector. That itself can be frustrating, as when the adjustment is tightened, it can create a “pinch groove” in the cable, and when trying to take up any stretch, the clamping section can tend to slip back into the previous indentation on the cable.

One other problem can be with the outer cable case. I had was an occasion where the outer cable casing fractured at the chassis post, beneath the nut where the case joins the threaded section. When this occurred, the tendency was for the case to move to the drivers side with the natural tension exerted on it, and this prevented reverse from being selected, as well as making normal gear changing very hard. on the chassis.

I once purchased a spare box, and its cable case had completely worn through at the side of the box, and the case was full of hard set dirt that was mixed with oil, making the movement very stiff. I mentioned this to another owner here, and he said that his case had worn through like this, and he had repaired it by cutting it into two pieces, cleaning it out and then rejoining it with a brass tube connector.

On the same topic, an 83 year old owner who has restored an A90 convertible, happens to be a specialist Borg Warner gearbox technician, and he initially had an adjustment problem. He added a spring to the bottom lever, fitted to the left chassis side, to ensure the lever could be pushed all the way back to the left side when this occurs with gear changing. I also now have this on my car, more as a safe guard than anything.

However, when investigating the problem of gear changing, he found that in the internal selector gate lever that positions the selectors, the spring loaded point in the gear stop plate was not engaging into the indentation on the gate lever, which is the neutral position, which can lead to problems. He has subsequently devised a “fix” for this, which is a much more robust type of spring loaded pin.

Having a spare gate selector, I checked it and did observe that the original spring loaded pin did not engage the divot in it, passing about 1/2mm to the side of it. It is important to have the neutral position selected when setting the adjustment, and this does does that. Without it engaging properly, could also attribute to making adjustments harder to undertake. I would expect that the your column A40 box would be the same.

In my old C/V, when I purchased it, it was fitted with an Austin 16 floor change box, which I undertook over 200,000 miles in, before replacing it with an original A90 column change. On that box, the gear stop plate had no spring loaded pin, and was never fitted with one. I would conclude that at some point, Austin had become aware of a problem, otherwise it would never have been fitted with the spring loaded pin for the neutral position.

Anyway-hope all is well. Cheers-Peter

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