axle position - weird and confusing

[KayTee]

Hello, everyone !

I am restoring a life-axle short cockpit 7. The chassis has been restored/modified by Arch, so it should be 110% OK.

The axle I have is an RS2000 Ford one, and has the proper brackets and braces attached by Redline Components. I am using a rose-jointed A-frame, which sits bang-on in the middle of the chassis.

We put the axle into the car yesterday. Measuring brake-back-plate vs. chassis rails shows that the axle is spot-on in the centre of the car.

 

- the right railing arm needed 2.5 thick washers between itself and the axle bracket

- the left trailing arm wants 4-6 mm of spacing between itself and the bush in the chassis, while resting on the axle bracket

- the diff is all the way over to the right of the rear tunnel aperture, the flange apparently partially outside the 'rim' formed by the cut-out bulkhead

It looks as if there is no way for a prop-shaft not to touch the steel reinforcing 'hoop' inside the tunnel. the diff-prop flange hs threads in it and is used with bolts only.

 

The friend helping me had his '88 Cat with him, and on his car the diff seems to have been modified (the 'nose' towards the flange removed and the flange turned-down and used with through bolts and nuts). His is a long-cockpit car, though, and he had to open the tunnel rear right end to gain some space for the diff.

 

What is wrong with this picture ?

Should I use the 3mm variation allowed according to the build manual and move the axle towards the left by that amount?

Does the original English diff have to be modified for use in a 7 ??

 

THANKS a lot in advance for any and all pointers!!

 

Regards - Karsten

[R2D2]

I would imagine that the brackets are not in the correct position on the axle otherwise the diff nose must be about centre.

 

There are a few points that you could check and look at.

 

I would measure the relative position of all of the axle brackets to the end of the half shafts and be confident that they have all been put on in the correct position. It should be quite easy to measure the chassis pick ups from the centre line.

 

I wouldn't measure to the back plate of the brakes. I would measure to the inside flange of the drum. I have seen RS2000s with slightly bent back plates. (Do you have the standard 8" drums fitted?)

 

I would check that the axle itself isn't slightly bent as this can occur with English casings that have had a hard life.

 

I would also check the Wheelbase on both sides to make sure that it is very similar and the length of the radius arms.

 

Having mapped it all out the cause of the problem should become clear. I know its a bit pedantic but the devil will always be in the detail.

 

 

(The confusing thing is that if the axle is in the centre of the car the diff nose must be the centre as well unless something is very badly out of line)

 

I don't much like the sound of the spacers between the chassis and the radius arm being 6mm.

 

What year is your car? It sounds as if your friend has an Ital axled car and the prop flange is smaller, but surely if the axle is correctly centered ther will be enough clearance for the larger flange.

 

There is a simple way to reduce the diff flange diameter. You need to find an output flange from a Mk1 Cortina, Anglia, Corsair. These all had much smaller diameter output flanges to the later Mk1 and Mk2 RS2000s. (Some Mk2 RS2000s had a "baby" Atlas with a rear loading ZF diff fitted as standard but this is very different to the English axle)

 

(I am confused by you comments about using nuts and bolts on the prop flange. My Mk1 RS2000 uses nuts and bolts in the location as standard.)

 

[deanteam]

Was the chassis built for the Ford axle, as I understand it the Ital diff housing is smaller. With the Ford diff the prop does go off centre towards the back. There are also different flange sizes prop-shaft to diff, the larger one interfering with the a-frame. Not too sure of the threaded flanges, ours bolt through. I would centre the axle. Are the trailing arms straight?

[John]

It is right that the diff nose is off set to one side on an English axle. The axle should be fitted centrally in the car by measuring the wheels to the chassis, ignoring the diff. The diff input flange may well foul the tunnel. This is usually overcome by using a smaller diameter input flange of 3 3/8 inch diameter as used on Ford Anglia. A standard Escort diff will have a large diametre flange. New small flanges are available from Tran-X in Coventry, England (02476 659061

 

John

[R2D2]

Interesting. I have messed around with English axles in Escorts for years and never noticed the diff was offset. Will measure a spare one that I have lying around.

[STEVE GILBERT]

I would like to add that the small type diff flange was also fitted to the 1100 Mk2 Escort, which had the one part prop. I was at Ford Spares, Tendring, Colchester, recently and they had props and Diffs with these parts. It is possible to get the Flange off and on again without too much drama. I have various Haynes manuals which cover the subject and describe string etc for checking preload which sounded more hap hazzard than the second method, which is to torque up to 20lbft. This was what what I did. I did take the diff out of the axle so I was able to confirm the backlash before and after with a feeler guage. My axle was silent after and still is for the current owner of the car.

[KayTee]

Thanks for all your replies!

 

First: Yes, the diff flange is off-set towards the right, this is because of the cwp arrangement. The crown wheel runs in a 'bulge' in the rear tin couver of the axle casing.

It is an 'English' axle with 9" drum brakes, 'groovy' drums, a Quaife ATB diff and has been modified (the case) @ Redline Components.

 

Don't they check for straightness when they put the brackets on ?? I assumed so. Possibly wrongly ?!?!?

 

The trailing arms are the 'curved' ones, bought for pure nostalgic reasons, and from a Lotus parts specialist in Germany. He buys Caterham/Redline spares. It may well be that the rubber bushes inside these are not 100% straight and therefore call for the huge spacing on the laft side. Not my main concern. They'll have to live with that ;-)

 

The chassis was specified to be for use with a Ford axle. My friend's car is along-cockpit one that usually has an Ital axle in it, but was changed to Ford when the previous owner had it built. Therefore his space probs regarding tunnel and diff. My diff flange sits about 2" back from the tunnel entry, but still of to the right in a fashion that indicated physical contact between prop and tunnel.

 

Hmm, smaller flange, very possible !! That means out with axle & diff, and find someone who can re-adjust the play in the doff properly. Brillaint. Do you know how many people can still do this in Germany ? I don't know a single person.

I have the old workshop manual for Escorts, will those directions be true for the Quaife ATB diff, as well ?

 

'Sigh' there goes one of my diff gaskets. (I had to purchase TEN, because the local Fraud dealer (a) didn't have them, (b) could only order TEN, and © did not WANT to stock them, so I had to buy all or leave).

 

Gosh, doesn't it ever end ??

 

So, Tran-X are the ones for the smaller diff flange ? They will know what I want when I call ?? Hopefully. I won't even start thinking about the price for that thing ...

 

I'll also measure the bracket - end of axle distances. Well, the wheels are relevant. I'll use those instead.

 

THANKS !!

 

Confused - Karsten

 

 

[R2D2]

Karsten,

 

Sorry to be a pain but I wouldn't use a diff to axle case gasket. Ford recommended the use of a silicone sealant to replace the gasket in a "Workshop Modification" sheet they published for Lotus Cortinas quite a few years ago.

 

I have used a sealant since then on quite a few rally car axles without any problem.

 

If you need a small flange it should be quite easy to get one here in the UK and there are quite a few old Ford spares suppliers on the web.

 

The backlash adjustment on the CWP shouldn't really change with an LSD. I have always used the same figure as in the Ford Manual with a plate type LSD but have never used a Quaife type unit.

 

I would think that Redline should probably have checked the axle as I ahve done business with them before and they seem very good- but - I have become quite cynical over the years and tend to check everything that I buy because I have had too many parts delivered that don't fit.

 

Tran-X are quite helpful and a diff/prop flange should be an adequate description, shouldn't be too expensive.

[deanteam]

Where abouts in Germany? We are close to Konstanz. We know someone who can deal with Ford axles in Switzerland. Our cars also have the Ford axles sitting towards the right in the tunnel, that is less of a problem as the axle is fairly well located laterally by the a-frame. If your flange does not interfer with the cross bracing of the a-frame when the car is jacked up then I would guess you have the smaller flange.

 

[EFA]

Karsten,

 

Your axle case was modified to fit the Seven on a jig at Arch Motors also.

 

 

 

 

 

Fat Arn

The NOW PROVEN R500 Eaterid=red>

See the Lotus Seven Club 4 Counties Area Website hereid=green>

 

[KayTee]

Thanks for all the replies !

 

No gasket ? Brilliant. 8 left, any takers? wink.gif

 

The flange does not touch the a-frame, even in its lowes position (brackets resting on the lower chassis rails), so it's a small flange, then ? Is that the 'correct' one ?

 

Brilliant, the axle was modified @ Arches, too ?? Why didn't anyone tell me before?? I ordered bit off Arch at the same time as the axle case went to Redline ...

 

Soooo, (a) measure distances of either axle end to lowest chassis rail (the flange the brake-back-plate bolts to)

(b) measure prop-flange diametre

 

Anything else to be done right now?

 

BTW., I am in Osnabruech, Lower-Saxony. 400 miles north of Konstanz. *Not really* next door, so to speak. Thanks for the offer !

 

What's a good source for a proper prop-shaft ('rocket' 4-speed to English axle in short-cockpit 7) ??

 

Thanks !!! - Karsten

[KayTee]

OK, I checked everything.

 

The axle is bang-on in the middle, checked by measuring space between back of brake-backplate mounting flange and chassis rail. To the mm.

 

The diff flange does not touch the a-frame, even when it's sitting all the way down on the chassis rails. It doesn't seem to acutlly be touching the tunnel entry, either. It's just offset to the right.

 

The diff flange has a diameter of 105-something mm, 4.whatsit inches. Time for a small flange ? There is a 'nose' on the front of the diff casing itself, currently prohibiting the use of bolt & nuts on that flange, does that need to be removed, as well ??

Do I gather, it's time to remove the axle, take the diff out, remove the flange, get another one, grind the 'nose' off the diff case, hope to be able to adjust diff ülay peoperly and reverse the whole thing ??

 

Which diff flanges were used in the 7 originally, and do std. propshafts fit to these only ?

 

Thanks for your time !

 

best regards - Karsten

[Fast Westie]

Karsten

As previously stated you need a diff flange from a 1100 Ford Escort with a Timken type diff. These are often refered to as the "English" diff and are not the same as the Salisbury diffs used in European Escorts.

 

There are a number of second hand Ford part suppliers in the UK that can help you out, or you can buy a new one from Westfie1d since they use them on their live axle cars.

 

To fit the new flange

- remove the axle,

- mark the position of the flange nut compared to the input shaft,

- remove old flange and fit new one checking that the seal is OK

- tighten the flange nut to the same position as the original

- refit axle

 

The size of the error in axle position would not suprise me. Despite being built on a jig I doubt if any 7 type car is truely "straight"

 

The car in front is a Westfie1d wink.gif

[deanteam]

I believe the small flange is the correct one for the car, otherwise the problem with the a-frame. Perhaps specify when you order the propshaft. Getting the bolts into the flanges, diff and propshaft, I find tiresome. On ours the bolts are put in from the back and the heads then clear the diff housing. I find there is only one position from which I can put a bolt into the flange, lower left quadrant. The bolts need to be the correct length to help.