DIY petrol engine repairs

Ever tried rebuilding a land Rover petrol engine – say the 3.5 or 3.9 version? Yes it can be done by anyone reasonably handy but there are many tricks and traps in the process. Here is an excerpt from the full article that appears on the Graeme Cooper website – just one of many articles at http://www.graemecooper.com.au/articles.htm

If you think you can save money by rebuilding your own engine – good luck! Unless you have a) done this before and/or have fairly extensive mechanical experience b) comprehensive variety of workshop tools, c) a workshop manual and d) heaps of patience, you will soon come to realise that what seems like too much money to pay a professional workshop is actually the cheapest and most efficient solution.

One major reason the professional cost seems high is that the work is warranted, meaning if the job is botched, it will be redone at the shop’s expense. Second hand or after-market parts will also not be used unless they are from a known and proven source.  Also, even existing components will be inspected by someone who knows what to look for and anything suspect will be replaced or repaired. Here are some examples:

  • Cylinder heads may be warped or have gone soft from heat over a long period. Unless they are tested and if necessary straightened at a cost of up to $1500 a pair, they are effectively worthless.
  • Stripped threads will prevent bolts being refitted to the specified torque, so coolant, oil and/or compression leakage is inevitable. The professional shop may be able to fit helicoils or re-tap the threads – not something most home mechanics can do.
  • Reuse of gaskets is false economy – replacements may add a few hundred dollars to the price of the job but this is unavoidable for a successful result

The same applies to many of the hoses, especially those that are hard to access

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