G
Guest
Guest
I had to have a new (well, secondhand Japanese import) engine fitted to my
petrol cruiser about nine months ago. The reason was incorrect fuelling, my
cruiser is LPG converted (which BTW now makes my cruiser cheaper to run than
a diesel version) and I was switching over to LPG way too early. It has a
rev controlled changeover system whereby it switches from petrol to lpg as
soon as the revs go above 2000 and then rapidly fall back below 2000 -
there's no temperature or timer control. Because of the early switchover the
petrol injectors were not used enough and they gummed up hence when I
eventually tried to run on petrol it had a very erratic and lumpy power
curve; some of you may remember my long running head-scratching about the
problem on here. Also because the lpg switchover was happening too early the
evaporator hadn't warmed up properly and the lpg was not properly vapourised
before being drawn into the manifold.
About nine months ago I suffered a leaking head gasket that I duly got
renewed but I still had a problem that, to cut a long story short, was
finally identified by a process of elimination as a cracked block. I spoke
to various specialist companies about this, partly because I was thinking
about getting the block repaired and several of them said that this was a
known problem in several Japanese engines, they are very heat sensitive and
suffer from block cracking if not looked after properly. My gummed injectors
were spraying neat petrol into the bores which was causing localised
overheating exacerbated by the early LPG changeover.
So I had a new engine and injectors which is performing very well indeed and
I'm very careful now to a) make sure I run on petrol for at least five miles
before allowing the changeover to lpg, b) run a full tank of petrol through
the engine regularly and c) occasionally chuck in a bottle of injector
cleaner.
The moral and relevance? I'm not sure but my experience is an indicator of
the sort of problems that can occur by tinkering with the fuelling in some
way. Just a cautionary tale really I suppose.
Pete
No virus found in this incoming message.
Checked by AVG.
Version: 8.0.101 / Virus Database: 270.4.3/1524 - Release Date: 6/28/2008
7:42 PM
petrol cruiser about nine months ago. The reason was incorrect fuelling, my
cruiser is LPG converted (which BTW now makes my cruiser cheaper to run than
a diesel version) and I was switching over to LPG way too early. It has a
rev controlled changeover system whereby it switches from petrol to lpg as
soon as the revs go above 2000 and then rapidly fall back below 2000 -
there's no temperature or timer control. Because of the early switchover the
petrol injectors were not used enough and they gummed up hence when I
eventually tried to run on petrol it had a very erratic and lumpy power
curve; some of you may remember my long running head-scratching about the
problem on here. Also because the lpg switchover was happening too early the
evaporator hadn't warmed up properly and the lpg was not properly vapourised
before being drawn into the manifold.
About nine months ago I suffered a leaking head gasket that I duly got
renewed but I still had a problem that, to cut a long story short, was
finally identified by a process of elimination as a cracked block. I spoke
to various specialist companies about this, partly because I was thinking
about getting the block repaired and several of them said that this was a
known problem in several Japanese engines, they are very heat sensitive and
suffer from block cracking if not looked after properly. My gummed injectors
were spraying neat petrol into the bores which was causing localised
overheating exacerbated by the early LPG changeover.
So I had a new engine and injectors which is performing very well indeed and
I'm very careful now to a) make sure I run on petrol for at least five miles
before allowing the changeover to lpg, b) run a full tank of petrol through
the engine regularly and c) occasionally chuck in a bottle of injector
cleaner.
The moral and relevance? I'm not sure but my experience is an indicator of
the sort of problems that can occur by tinkering with the fuelling in some
way. Just a cautionary tale really I suppose.
Pete
No virus found in this incoming message.
Checked by AVG.
Version: 8.0.101 / Virus Database: 270.4.3/1524 - Release Date: 6/28/2008
7:42 PM
