Land Rover crank re-grind. - D J Woollard
Soon to "minimum cost" rebuild a Land Rover Series III diesel engine. This was running well until a long motorway journey with a low oil level (not me!). The No.1 big end failed, picking up the bearing shell and spinning it round in the con-rod. Otherwise the engine was dry and oil tight at a genuine 80,000 miles.
I am well experienced in such work but the Land Rover experts are full of conflicting advice about the possibility of re-grinding the crank. Several say never to re-grind a LR diesel crank but buy new, others say a sensible minimum re-grind is ok and some even boast of obtaining special shells to grind down to the size of a pencil if needed!
Anyone with real experience of this particular engine and crank to give a definitive answer.
Thanks,
David
Re: Land Rover crank re-grind. - Dave N
Try Colin Cowley (or his son John) on 01908 501713, they have been LR specialists for donkey's years. They can't regrind, but will tell you what is possible.
Re: Land Rover crank re-grind. - John Slaughter
Friend of mine had a SIII diesel years ago, on which I helped with a number of jobs - everything's so damn heavy! As I recall, the 'don't regrind' advice comes from the LR workshop manual. However, my advice is the same as Dave's - get 'Land Rover Owner' (if you don't already) and ring up a few of the specialists and take a poll of their advice - it won't be new to them. We could never understand why the advice was given - it could be that it needs to be done carefully, with proper corner radii etc to avoid stress raisers, but it's difficult to believe that there is insufficient strength in the component to make a 10 or even 20 thou grind a big issue.

Regards

John
L.Rover crank re-grind - more please. - D J Woollard
Thanks guys so far, John in particular. Yes I do read LRO, also have phoned round several specialists and engine workshops. And there is the problem, the views are so varied that I really want a definitive answer from someone who knows the engineering truth behind this. You did mention the one important issue, if a re-grind is considered how it is carried with regard to radii finishing seems important.
Hopefully some more tech postings will arrive on this soon.
David
Re: L.Rover crank re-grind - more please. - John Slaughter
David

Have you considered ringing Land-Rover - views might have changed and you may find the reason behind this. I seem to recall that the petrol and diesel engines are similar in major components - which may explain why in the diesel version components are more stressed, so this may be the reason.

Given the disparity of views, clearly a number of the cranks have been reground - clearly for cost reasons. Have these been sucessful, or have there been problems or failures? Is there a L-R website? How hard do you drive the vehicle?

If the reground engines seem to have been OK, then it seems L-R are being overcautious.

Regards

John
Re: L.Rover crank re-grind - more please. - andrew smith
From what I remember of these things the diesel engine was engineered out of the petrol engine. It's possible that Land Rover regarded the whole shebang as being under engineered in the first place and were consequently reluctant to recommend any course of action that would weaken it further.
Would a replacement unit cost that much more?
Re: Land Rover crank re-grind. - Andrew Hamilton
Ideally to prevent cracks the conrod needs to be polished to remove all surface scratches. But I guess that is only done in racing engines!