Something really weird like the fan broken in half but still held on by a bolt on each half?

Location: On a hill in Wiltshire

Just a little more info!

When I spin the engine with the starter or with the starting handle
I don\'t hear any of the clanking noise. It appears the noise occurs
only when the engine is fired up and running at low and high revs.

I\'m going to try and borrow a stethascope from a fellow Seven owner
to try and identify exactly where the noise is eminating from.

I think I\'m now approaching the time when I will have to remove the engine once again to examine more closely the camshaft and crakshaft and their respective bearings, because I\'m now convinced that the problem lies in that area.

My thanks to all for your helpfull suggestions.

Ray B.

Location: Prestatyn

"After having a carburettor problem"
What did you remove or look at or adjust whilst fixing this first problem?
The inference is that occurred right after you fixed this problem?
Good luck
Steve.

Location: patrolling the border

If the other answers have not helped, a clanking noise from the front of the engine sounds to me like excessive camshaft end float and or timing gear lash. Although quite why this should suddenly appear following a carb problem is beyond me.

Easy Captcha 1317

Location: NZ

perhaps excessive end float in the crank due to worn main bearings.

My old engine wore so that the crank belted the crankcase at the cam centre bearing when it felt like it. 20mins with a file and hoover got another 2000miles out of it before it happened again and it was new engine time.

Location: Market Drayton

Steve, the problem I had with the carb was flooding due to
the float being half full of petrol because it had developed
3 hairline cracks. I managed to repair the float with solder
and it was during the adjustment of the carb that the clanking
noise was heard.

I did assume that it was a big end failing, but proved not to
be the case.

Ray B.

Location: Prestatyn

I\'ve managed to remove the engine and dismantle
the it and the following is what I have found.

The big and little ends are in good condition with no
serious wear evident.

The pistons, rings and cylinders are in very good condition.

The crankshaft bearings are working smoothly without any
odd grating noises and the crankshaft itself is running true
and is undamaged.

The camshaft is not in good condition with pitting to 3
cams and the centre roller bearing.

The camshaft has excessive end float much more than the recommended.002 thou.

When I grip the pinion gear and pull it makes a loud metallic sound, so
I'm wondering if this is the cause of the clanging that I've been hearing.

I intend to replace the camshaft when I can locate one that is in good condition.

Lastly, All seems well with the clutch and flywheel and I'm sure the noise problem is not coming from that area.

I would appreciate any comments/advice as the whether I am correct in believing that the camshaft end float is the cause of the clanking noise.

Your comments will be appreciated.

Location: Prestatyn

Ray,
As I stated above, based on my experience the excessive end float is a common problem and highly likely to cause the noise, not to mention wear of the locating pin threads and subsequent oil leaks.

Location: NZ

Hello Ian,

Thank you for your reply and interesting comments.

I'm on the search for a replacement cam shaft as I am of the
opinion that due to deep pitting of the cams and serious wear/endfloat
it is beyaond economical repair.

I've noticed that the endfloat on the camshaft main bearing is about 3-4 mm,
do you think that this amount of movement would cause a loud clanking noise?

I've also decided to replace the centre roller bearings and cage as it also has pitting and wear. The roller cage is in a housing in the crankcase which doesn't look too robust and I'm a little concerned about tackling it's removal. Do you have any advive to assist me to remove it safely?

Also, I've decided to replace 3 cam followers due to serious pitting, maybe they contributed to the clanging noise!!

It seems that this engine has been seriousely neglected over it's life time,
but I suppose it's understandable and should be expected as it is 81 years old!!

Best wishes from Wales.

Location: Prestatyn

Ray,

it was good to speak to you yesterday.

The end float on your camshaft should be 0.002" (2 thou), you have far too much currently and, as Ian suggests, it will make a terrible racket. You can adjust the gap by carefully using grinding paste on the taper.

I recommend you buy a new bush for the camshaft and you should check the size of the one you take out before replacing it as several sizes exist. I dispense with the square headed bolt that holds the bush in place, tap the locating hole in the bush to 5/16 BSW and then use a bolt and Loctite to secure it all (check also that the end cap for the camshaft (flywheel end) is the correct size as, again, several different sizes exist).

I carefully use a suitably sized socket on the end of an old extension bar to drive the cam shaft centre ring out, you must take care when doing this and some careful heating around the aluminium in this area will assist. I use the same socket to push the new ring in place making sure the inner recessed end faces the front of the engine.

I recommend that you get all the cam follower faces machined smooth and also the tops of the tappets machined flat.

End float in the cam can chew the timing gears quite quickly so looking at getting good replacement ones (new or 2nd hand) might be wise as well.

If you do this and find a nice replacement camshaft I think you will be very pleased with the results.

I agree with almost everything that Ruairdh has said with one exception. The locating Pin has two thread types depending on year 5/16 BSF and BSW, so if you were to extend that thread into the bush use the correct tap. The problem with that method is that it can still allow the bush to float in its housing and over time the thread will eventually wear, particularly if the bush end float is not kept in check. Personally I believe that the best option is to replicate the magneto crankcase arrangement where a stud is screwed into the bush, you need to remove the thread in the case, a lock nut then clamps the bush securely into its housing. I hope that makes sense, a couple of pictures would explain so much.

Location: NZ

I can't understand how you can get 3-4mm of endfloat between the camshaft/gear/bush?.
If you have then you will need new/replacement timing gears.

Thank you Gentlemen for your excellent advice, I guess
it's up to me now to put your advice into practice and
make a good job of servicing this ancient 2 bearing crank
engine of mine!

Best wishes from Prestatyn.

Location: Prestatyn, North Wales.

I'm in the middle of rebuilding my 1934 2 bearing engine and on refitting the camshaft realise that I too have excessive camshaft end float... Somewhere in the region of 3mm!! I'd heard of the solution that is mentioned above regarding the grinding paste on the taper but would that really be viable for such a gap? I could imagine resolving something like 10 or 15thou this way but 3mm??

Am I right in thinking that the end float is due to the brass bush wearing rather than a problem with the cam?

Good luck ray with the rebuild!
Cheers
Robbie

Location: Horsham

with it being on a taper, you would be suprised how little you need to remove to get a big result.

However I would start off by trying different sets of gears to improve things a bit first. Assuming of course you have a box full.

Robbie,

I agree with Hedd's comments and am very happy to talk you through the procedure I use on 0141 942 8037 if that would help you.

Thanks Guys

Ruairidh, I'm actually up in your neck of the woods this weekend as visiting the inlaws in Stranraer but flying into Glasgow...

I'll give you a call..
cheers
Robbie

Location: Horsham

Hi Robbie,

I'm having fun, chasing a supercharger type noise (without the supercharger type performance). I've been considering the camshaft timing gear float, and can only believe that it is the wearing of the bush that causes it. So I will be trying to get hold of a new bush, as recommended by Ian D (can anyone recommend a supplier?). I want to leave grinding the gear onto the camshaft as a last (2nd) resort.

By the way - I don't believe my noise is due to this, but it is a bit of needed housekeeping. My noise started all of a sudden, on the way to Beaulieu. I've had some investigations, but I'm busy wearing it out some more since then. I've done 1500 miles since the noise started, and it's not got any worse. My worrying only lasted a short while. Maybe if I stop using the car for a few weeks, I might get deeper into the engine to find out what it is. I'll try to remember to update the forum, if I ever get round to solving the problem.

All the best,
Colin

Location: Towcester

Are you getting a whistle noise Colin?

Air leak on induction side, carb, gasket?

Hi Ruairidh,

I'm pretty certain it's more mechanical than that.

It's a similar noise to the one you get when the dynamo gear is in too tight a mesh with the camshaft gear. It's not this, as it suddenly began 50 miles into a journey. There's no sign of gear wear, on the timing gears.
I've since changed the dynamo, and still got the same noise.

I've played about with metal rods, as stethascopes, but yesterday realised that the 'proper' things are only about £4 off of ebay, so I've got one of those coming.

My gut feeling at the moment, is that something has happened to the 9 rollers on the camshaft.

Thanks again for your suggestion Ruairidh. I will eliminate that, next time I get time for a play.

Regards,
Colin

Location: Towcester

Hi Colin

I've also been looking for a replacement camshaft front bush but can't seem to find one yet. I've looked on the usual suspects sites (seven workshop, 7county Austins, A7 Components etc.) but none seem to stock such a part..

Anyone any idea where we can get one?

cheers
R

Location: Horsham

Tony Betts will be able to help you, only a very (very) small percentage of his stock is shown on his website.

Thanks Ruairidh,

Looks like I'll resort to the long lost art of actually calling someone and speaking to them in person rather than failing with the anonymity of searching a website

cheers
R

Location: Horsham

PROBLEM SOLVED!!!

Firstly, may I offer my grateful thanks to all who offered advice
which has enabled me to solve the 'clanking noise' problem with my
Seven engine.

Work carried out.

1. Purchased a very good condition camshaft and bearing from Tony Betts.
2. Purchased center cage and rollers.
3. Tapped the camshaft bearing and fitted a locking stud.
4. Ground the timing gear onto the camshaft taper and atcheived 0.002 thou clearance.
5. Purchased and fitted a double set of valve springs.
6. Purchased new clutch springs.
7. Had the tappits ground flat.
8. Purchased a cheap honing tool and honed the cylinders ( £ 12.00 )
9. Relined the clutch.
10. Purchased new set of gasgets.

Location: Prestatyn, North Wales.

The result of all the replacement parts and work carried out
is that I now have an engine that is running sweat and without
that dreaded clanking noise.

I've had several runs and have clocked up about 120 miles since the overhaul and I'm delighted to say that the engine runs smoothly and pulls very well
indeed.

Again my sincere thanks to all for your valuable advice.

Location: Prestatyn, North Wales.

Great news, long may it last!