Lightweight Dif Movement

[Guest jamesandrew]

Hi all,

Just been reading some lightweight posts and decided to rock my car in gear to see if there was any dif movement from the chasis.

Seems to be a bit of movement there e.g rubbing not clonking sound.

Any ideas how to check this out as panels seem to surround dif and are rivited in.

Car was originally built by Diyer so some of you will know the car.

Thanks Andrew

[philshelton]

think you will have to cut an access hole in the rear panel sugest you contact the lightweight orical AKA GDC

[Guest gdc]

hi andrew

before the big panic sets in give me a call .

07860789193

may or may not be diff movement .

read as much as you can on this site and the link below .

let me know how much of the diff you can see , ie remove 1 or both the rear wheels and check if any strengthening has been carried out .

photos will help .

i had this prob with both of my lightweights and they are both cured , its not easy to do but it can be done .

my st is putting out over 200bhp and with the moddification is working well .

ring me and poss visit and see the mods .

graham

[Guest gdc]

hi i have spoken to andrew tonight on the phone and he is trying to describe his problems .

i will report when he has delved deeper into the chassis

 

graham

[Guest jamesandrew]

hi Graham

Thanks for chat last night, I have put the car on 4 post lift and managed to take photos of near side front dif mounting bolt.

Seems like it has moved down about 8 mm judging by new shiny metal showing above washer. Off side front bolt seems ok and have not had time to look at the 2 rear mounting bolts for the dif, i take it 4 bolts hold the dif on. Will try to have a more thorough look tomorrow and report back.

Thanks Andrew

[Guest gdc]

Hi Andrew

you do have diff movement, if you didn't already know . I feel that the centre bolts are less affected so dont need attention . However whlist tackling the area, bond some large washers, or 5mm plate either side of the centre mounts to add strength . Re the front and rear mounts, replicate the original rear mount from angle and plate and bolt to the boot floor from the positon of the bolts in the boot floor triangulate 2 plates up to the bottom of the roll bar and anchor it all together . On the front nose fixing of the diff , you will need to form a u section of 5mm flat steel about 20 to 25 mm wide , make the bottom the same width as the inside of the tunnel ,masure the height to the front nosefixingfrom the bottom of the main seciton of the floor of the tunnel and add 50mm for the overall length from the bottom of the tunnel measure to the centre of the fixing hole and drill a hole to suit the fixing, easy to say, not to do . Using a grinder, slot out below the fixing in the main floor plate so as to insert the u section , the u section at 5mm thick will just squeeze though the gap and do away with the spacer washers that were in once the u is in place drill through it and the floor, then cut another piece of 5mm plate to sandwich the floor section and bolt it all together .

you will need to remove the seats carpet and tunnle top to carry out the work .

I wish you luck, if you need more info please phone me, if you are unable to complete, I may be able to do it, but the car would need to be bought here .

 

graham

[Guest jamesandrew]

Hi

Just an update

Have taken off center tunnel top to expose front of diff ,noticed a drip of oil from oil seal aswell ,is this an easy fix eg remove prop,center bolt,remove pulley,take out old seal and drift in new seal , reasemble.

 

Have taken off rear number plate to see rear off diff,will get some steel to start to strenghten asap.

Thanks to graham for advice

andrew

[Longboarder]

noticed a drip of oil from oil seal as well

Fix can be as you describe for the seal but the oil can also leak between the splines on the pinion gear shaft and the splines on the flange. In this case the oil appears from under the flange bolt rather than over the nose of the diff case. Silicone to the splines on reassembly cures this.

 

Nigel

[Guest jamesandrew]

Thanks Nigel

Will have a good look to see where it is coming from ,if it is the splines do i still change the seal.

 

cheers andrew

[Longboarder]

My new seal is still in the spares box. As the old one is still working perfectly I decided to leave it alone and just fix the leak along the splines. You might think that a false economy and you would probably be right on a newish car but I've learned the hard way when fiddling with ancient car bits, don't get carried away. I have destroyed too many perfectly serviceable lumps of old car with the best of intentions in mind. If it aint broke......etc.

 

Nigel

[Guest jamesandrew]

Hi all just an update on the diff strengthening. I have strengthened front bolts by sandwiching with steel either side, not as a u section because of brake pipes at bottom of tunnel. I have put some side strenghtening on rear bolts and sandwiched it to body work. The centre bolt has just a large washer on it. Back of diff have bolted a plate to it, and bolted it to boot floor by sandwiching it with another piece of steel, all steel has been grip filled aswell as bolting in place. I hope this does the trick, was a real pain to do because as you know there is no access. I have attached some photos to try to show what I have done.

Thanks for all help and advice will try car out soon.

Andrew

[Guest gdc]

hi andrew

theres more than one way to skin a cat . looks like that may well do the job , give it some real stick

acceleration and deceleration then check it all again . bet you have some grazes and scrapes on the arms now though .

good luck with it , dont forget there ant many of us on the road so pretty unique .

all the best graham