Not a simple repair after all
ONE of the hazards of writing this column is that sometimes a job that I write about comes back to bite me hard, after my piece on it has gone to press. Last month I described how I had saved the owner of a Defender 200Tdi the cost of the engine rebuild he had asked me for, by diagnosing a couple of simple fuel system faults. There is a sad postscript.
Seeing as we still had £4850 left of his original £5000 budget, the owner asked me to give the vehicle a full service and thorough check over, and rectify any faults that I found. I had already noticed a minor clutch judder when reversing and the bottom of the flywheel housing was wet with oil. I suspected that the rear crank seal had failed, with oil contaminating the clutch plate. I agreed with the owner that I would pull the engine out, change the seal and fit a new clutch. The engine came out with no problems – as I expected the clutch plate was covered in oily muck. Removing the flywheel revealed oil trickling down from the bottom of the crank seal.
So far, so good. I now needed to remove the flywheel housing so that I could drift the old (metal cased) seal out and press a new one in square. Theoretically the seal could be changed with the housing still on the engine but it is a lot easier to do the job with the housing off. I unbolted the starter motor and immediately spotted a line of rust running vertically down the engine block. My heart sank. This is just where the 200Tdi block is weakest and most prone to frost cracking if the engine
is not protected with a good strong antifreeze mix.
I cleaned up the area and sprayed it with brake cleaning solvent. This finds its way into any crack and will show up as a dark line once it has dried off the surface. Sure enough the block had a long hairline crack in it. I got on the phone to the owner. “You know I said we wouldn’t have to rebuild your engine? Well...” Luckily I had a spare 200Tdi bottom end sitting around minus various important bits, so I now have the job of
building up a new engine around that block. It should be a bit special: balanced crank and flywheel, Turner gas-flowed head, Kolbenschmidt pistons and good quality components throughout. But what a waste: when I stripped the engine it was immaculate inside with perfect bores, unworn standard-size bearing shells and no sign of wear and tear anywhere. But for a few pounds worth of antifreeze it could have done another 200,000 miles. There’s a lesson in there.