Bump start peril

HI, Can you tell me if bump starting in reverse will b*gger up the gearbox on a S3 with a diesel engine?
My mate says yes and I say no.
There is a pint riding on the outcome.

you wont do it any good, I would be surprised if the engine turned over at all. it could bugger the diff, a half shaft or the gearbox. I have done this on a petrol but unless the compression is well down i dont think its a good idea.

Why is it a bad idea to bump start in reverse (why will it cause damage)

ciderman said:

HI, Can you tell me if bump starting in reverse will b*gger up the gearbox on a S3 with a diesel engine?
My mate says yes and I say no.
There is a pint riding on the outcome.

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depends how worn your box is ,reverse uses an idler gear slid in between 1st/2nd synchro hub and layshaft ,as it has to slide into mesh it has straight teeth and not helical like 1st ,2nd and 3rd which means teeth are weaker and why box whines in reverse ,reverse is also low geared so you will be trying to spin engine over very fast which will put extra strain on other drive train components and can end up with rear wheels turning in different directions ,it can be done as i have but dont get much speed up before releasing clutch

Reverse is usually the most direct gear for reversing, not sure on landys but i always bump cars in reverse where possible.

bigsi13 said:

Reverse is usually the most direct gear for reversing, not sure on landys but i always bump cars in reverse where possible.

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what about 3rd or 2nd ?

bigsi13 said:

Reverse is usually the most direct gear for bumping, not sure on landys but i always bump cars in reverse where possible.

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Thats better:banghead: just always found reverse easier

Having had over 40 years in the motor trade I prefer to be able to see where I'm going when bump starting. Going forward using 2nd or 3rd is a far safer option than using reverse, for a start brakes always work better going forward, using a higher gear places the drive train under much less strain.

I'm with Rob and James.

2nd gear works for me.

The higher the gear the faster you need to push to get the relevant engine speed , also the more mechanical advantage you get if large engine with high compression . If you go to low gear eg 1st or reverse the more inertia you need to build up to vercome the geared resistance of the engine , and therefore the more strain you will put on the bits connecting the engine to the wheels . LR halfshafts were at one time tested to survive a quantity of roll backs with clutch being engaged sharply , you will be basically repeating this type of test so guess the end result ?

second gear and engage the starter as the clutch is released for me.
have done it in reverse when desperate, but still use the starter as well.
preheat glowplugs before you roll tho!

Oh. a mixed review here.
I won't do it again then.