The front propshaft is now too short to reach the diff without being at fulll stretch at rest – any articulation will pop it apart. I’ll need a longer prop with a 4″ slip joint.
Another probelm that has had its solution decided on is the rear prop shaft. Due to the chassis having 1-ton extended spring hangers and shackles, combined with HD parabolics, the suspension is so tall thet the rear prop binds on the lower edge of the hole in the x-member behnd the gearbox. The options were to:
a) lower the suspension (severely dislike that option);
b) fit check straps under tension to draw the chassis down 1/2″ (not a good idea either);
c) cut away the part of the chassis that the prop is fouling (workable, but not ideal on a brand new galv chassis), or;
d) get a custom prop with a slim section where it passes through the rear of the x-member (similar diameter to the male section of the expansion joint).
Obviously, “d” is the way to go, especially as I need to get the front propshaft extended by approx 1.5″ (due to the same suspension reasons). There is a propshaft specialist in St Neots (Bailey Morris), not far from me, so that is the planned course of action (the Scorpion and Gon2Far props are good but a bit dear).
Hi Nick
Greetings from Africa.Thanks for a great site and advice so far, here some more problems, I am busy building a series 3 short wheel base and got a long wheel base scrap with all I need.Problem is the back diff seems to be wider than this of the short wheel, the leave springs in not the same as the short wheel base, they are mounted outside the chssis where the short wheel is on the chassis.Have you any comment on this?What other proplems or suprises can I expect using spares from a long s3 to build a short s3.
Thanks
Regards
Lukas
Hi again Lukas.
All 88″ models have both front and rear springs underneath the chassis’ main rails. 109s use the same front suspension arrangement, but the rear springs are mounted outboard of the chassis. This is to give the 109, with its greater net and gross weights, a bit more roll-resistance.
Fitting a 109 rear axle to an 88″ chassis needs modification of either the chassis or the axle. Since modifying the chassis would involve fitting spring and shackle hanger outriggers from a 109 and the installation of a new damper top mounting to each side with relatively little room to fit them all, fitting new spring saddles and bump stops adjacent to the existing ones on the 109 axle may be easier. I have seen it done both ways, and as long as the materials and welding are strong enough and correctly aligned, I don’t think either has much operational advantage.
There are three types of rear axle on the 109 – Rover, ENV and Salisbury. The Rover tyrpe looks the same as the front axle (less swivels), using the same type diff. The ENV axles have very large diff housings with a lot of reinforcing webs and a chunky diff pan (and are relatively rare). The Salisbury axle was standard on the SIII 109 and has an irregular diff housing which is a solid casting with the axle tubes stuck in each side. The Salisbury diff pan is bolted, rather than welded, but the diff carrier is integral, not bolted in like the Rover diff.
Salisbury axles are very tough – you’re unlikely to ever blow one in a Series vehicle. They can suffer wear like other mechanical parts if abused, though, and rebuilding them is very difficult compared to a Rover diff.
Nick.