Random & Catastrophic... 2.5 bits galore inc. LPG

After 4 months of very happy motoring, my 2.5 V6 has thrown a piston, cracking the block and a head!!!

I just do not have the time to put things
right and, since I'm dedicated to LPG, I've
had to go off reservation to get a replacement.

Cue Jeep Cherokee 3.7

As a result I have, but for the engine, a complete car.

It is a 2000, X-Reg 5 Door Station Wagon in pale metallic blue.

Good auto box, very good body, Wolfrace alloys with 2 near new tyres and 2 usable.

PM me and I will send pics. If you have the room I would rather let the whole thing go for a song to clear my space.

Marc

lpg on a kv6? no wonder

Oh, that old chestnut again! Something to point at and blame. I guess that awful pesky gas just cut a hole in the con rod! It had the conversion in 2002 so I wouldn't consider LPG even likely to be responsible!

Nope - LPG has a higher burn temp than petrol and has less of a cooling effect on the inlet valves, so not ideal in an engine with poor cooling and cavitation problems.

lpg doesnt burn hotter than petrol it has lower calorific value than petrol ,lpg doesnt cool valves as well as wet petrol mix

A French LPG bus manufacturer(MAN engines) had problems with high exhaust temps . Longer burn duration with the same ignition mapping as gasoline leads to the burn sequence still in process when the exhaust valve opens, torching the valve and seat. LPG provides less upper cylinder lubrication than petrol or diesel, as a consequence LPG fueled engines are more prone to wearing valves if not suitably modified and may cause higher piston (ring) to bore wear........ So the pistons, valve seats and plugs all run hotter for a given power level, consequently the margins are likely to be lower for an LPG fuelled system. This is also the reason most LPG systems also run a direct injection "Valve Protection System" to minimise valve seat recession caused by these higher combustion temperatures.

Look at the peak flame temp in the data below....


LPG (Propane) has a higher Autoignition and peak flame temp than petrol.

I am not stating that this is what caused the OP's problem - just that LPG is not advisable on the K series engines due to their susceptibility to cooking.

lean engines burn hotter

Thank you for all that information. Do you know that if you drain the oil out of your engine and start it up it's likely to experience a catastrophic failure?

Bleeding obvious you may say but what isn't obvious from many people's opinions about LPG is that it is like any other fuel. It has special properties and special requirements.

Just like keeping oil in your engine if you nod to what it needs you will benefit from what it offers. 75p/Ltr!! Case closed!

really?

No - I didnt know that. Could that be why it rattles a bit when running? :doh:

ya prick! I was merely pointing out that an engine which already has a weak spot in the cooling system is unlikely to benefit from a fuel which will increase burn temperatures. As it appears that you arent worried, then that is fine. You can suffer the consequences.

Silvertwinkie said:

75p/Ltr!! Dead Motor Case closed!

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edited for accuracy

Gentlemen, I came on here to discuss what matters. Not just to give you an opportunity to talk bollocks for your own entertainment. Good bye Land Rover! I'm ****ing well rid of you!

Silvertwinkie said:

Gentlemen, I came on here to discuss what matters. Not just to give you an opportunity to talk bollocks for your own entertainment. Good bye Land Rover! I'm ****ing well rid of you!

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jesus you will be missed

Silvertwinkie said:

Gentlemen, I came on here to discuss what matters. Not just to give you an opportunity to talk bollocks for your own entertainment. Good bye Land Rover! I'm ****ing well rid of you!

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....... scorned sook!

good luck tryna get rid of your 'dedicated' boat anchor!

BTW give you 6 weeks before you break ya Jeep too!

After a run to warm it up, then whilst sitting stationary wiv the engine on tick over, me hawkeye reads 109 degrees C when the fans come on. 105.9 degrees C when the fans switch off. Thats me v6 coolant temp.