buying engine off ebay - was run on lpg
02GF74 - 19/1/17 at 09:39 AM
in brief, friend needs new engine; found one on ebay for £ 350 that has 80 k miles and was run on lpg.
1. so is running on lpg any worse for wearing an engine compared to petrol?
2. it may be a while for it to be fitted (muggins here be doing that 
) so won't know if it is a good 'un until then - remind me what is
the time limit after purchase date for raising a dispute if it turns out bad?
3. any way to tell without taking it apart to check for any problems? (other than turning it over, looking at cam lobe wear, looking down spark plugs
holes - I think answer is no).
4. anyone in Watford area wanna help????"?? 
I'm aware that replacement engines with a couple months warranty are available for about £ 1k but the car is worth around that so needs to be
done on the cheap.
ReMan - 19/1/17 at 10:38 AM
quote:
Originally posted by 02GF74
in brief, friend needs new engine; found one on ebay for £ 350 that has 80 k miles and was run on lpg.
1. so is running on lpg any worse for wearing an engine compared to petrol?
2. it may be a while for it to be fitted (muggins here be doing that ) so won't know if it is a good 'un until then - remind me what is
the time limit after purchase date for raising a dispute if it turns out bad?
3. any way to tell without taking it apart to check for any problems? (other than turning it over, looking at cam lobe wear, looking down spark plugs
holes - I think answer is no).
4. anyone in Watford area wanna help????"??
I'm aware that replacement engines with a couple months warranty are available for about £ 1k but the car is worth around that so needs to be
done on the cheap.
Iirc, The main issue , provided it was run properly, is likely to be valve seat wear, but in this day and age even that's less likesly, since
unleaded.
As far as buying , at this level its at your risk, unless he's selling it as a new engine, you'd get nowhere on not as described IMHO. The
loveliness of ebay on a shoestring
r1_pete - 19/1/17 at 12:03 PM
A few things you could do:
a cylinder leak down test.
a peer in the bores with a boroscope - very cheap these days...
look inside the rocker / cam cover for evidence of regular oil changes, or any mayo....
coyoteboy - 19/1/17 at 12:03 PM
Depends on the engine, but most these days run hardened seats to cope with lack of lubrication as mentioned. Worth a leakdown test on any engine
though, shows up potential problems with both valve seats and rings so win win.
hughpinder - 19/1/17 at 04:53 PM
I ran 2 cars on lpg - a honda civic for 217,000 miles - no issues at all, and a subarulecacy 2.5 for about 80,000.
I had a problem with the piston rings on the subaru where the cylinders were still pressure tight, but passed oil, so it started to burn large
quantities of oil towards the end. I did get into discussion with someone who worked for the subaru works team for a while and he said they had the
same problem, but didnt know why.
I think most people have not had any great issues running on it.
Regards
Hugh
Oddified - 19/1/17 at 05:18 PM
As mentioned above, valve seat recession could be an issue on some older type engines, generally not on anything new ish since unleaded. In general
the wear on the rest of the engine will be lower than one run only on petrol because there's minimal particulates dumped in the oil, most oil
will still look like new at the regular oil changes.
Ian