GU 4.2td or GU 4.8 on gas

[[gubeaut]]

My old man is contemplating buying a nissan patrol for towing a caravan around aus and any info good or bad would be helpfull.the issue he has is that it was brought to his att that a bloke with a 4.2 overheated and the aircon kept cutting out towing across aus during fairly hot days though a few 3.0td didn't have these issues.though the 3.0td is also a possible option.As i am extremely biased towards the 4.2 (4.2tdi ute), he is thinking of buying a 4.8 and putting it on gas but niether he or i have heard any reviews.please let us know of any thoughts or experience you have had as it will be very helpfull

[blownba]

I fit Tartarini LPG injection to the 4.8's and they run so amazingly well you wouldnt believe it.
The last one I did had 6kw more at 3000rpm on gas than petrol at the wheels.
I have seen alot of horror stories with the 3.0L latley, especially if your towing with it. Expect to be up for a flywheel at the very least or a full rebuild worst case (fairly common) if you are considering long distance towing IMO.

[MyGQ]

Stay away from the 3.0L TD as they are know as the Handgrenade motor

the 4.2L TD is a great option as its the same engine that was released in 1988 with a few mods to the injector pump along the way to give it more power and the turbo really would help compared to the N/A slug i have.

the 4.8L engine is also based on the old 4.2L Petrol engine, same block just a few more mods to get it more power, and on gas it will be much cheaper, but towing on gas chews up fuel very quick, if you want speed and power, the 4.8 is the go.

[[gubeaut]]

I fit Tartarini LPG injection to the 4.8's and they run so amazingly well you wouldnt believe it.
The last one I did had 6kw more at 3000rpm on gas than petrol at the wheels.
I have seen alot of horror stories with the 3.0L latley, especially if your towing with it. Expect to be up for a flywheel at the very least or a full rebuild worst case (fairly common) if you are considering long distance towing IMO.

the only thing that i guess got him wondering was a bloke on the nissan patrol forum said that the 4.8 he had and put on gas ended up blowing valves seats and guides(and no i am not very mechanically minded) though it did go very well for a little while .All up it cost the bloke an extra $4000 to fix the issues

[gazza 1]

My old man is contemplating buying a nissan patrol for towing a caravan around aus and any info good or bad would be helpfull.the issue he has is that it was brought to his att that a bloke with a 4.2 overheated and the aircon kept cutting out towing across aus during fairly hot days though a few 3.0td didn't have these issues.though the 3.0td is also a possible option.As i am extremely biased towards the 4.2 (4.2tdi ute), he is thinking of buying a 4.8 and putting it on gas but niether he or i have heard any reviews.please let us know of any thoughts or experience you have had as it will be very helpfull

[gazza 1]

My old man is contemplating buying a nissan patrol for towing a caravan around aus and any info good or bad would be helpfull.the issue he has is that it was brought to his att that a bloke with a 4.2 overheated and the aircon kept cutting out towing across aus during fairly hot days though a few 3.0td didn't have these issues.though the 3.0td is also a possible option.As i am extremely biased towards the 4.2 (4.2tdi ute), he is thinking of buying a 4.8 and putting it on gas but niether he or i have heard any reviews.please let us know of any thoughts or experience you have had as it will be very helpfull

Mate i would go the 4.2 turbo Nissan and convert to diesel/gas Ive done it to mine and its great. Towed a 2 tonne caravan to the sunshine coast from melbourne with out any problems(and back) Well worth the cost.
Gazza

[simcoe]

depends how much you want to spend on fuel..?!
want power go the 4.8 but dont gas it,they dont like the gas like the 4.5 do.i know all cars are different but my mate who repairs heads say the 4.8=blown heads on gas! and dear to fix!

As the rest of the forum will tell you go the td42t and crank it up! They turn into a race car with some tuning/mods etc and way cheaper on fuel,exspecialy while towing then the 4.8!


my 2 cents
cheers

[GQ4.8coilcab]

later model 3litres are the best ones to buy (if there is such thing ) as they have had there oiling issues resolved. You really need to ride the clutch in 3litre because of were the power in the 3litre is made. Friends blew there clutch in the sand because you have to ride it to get going. Starting off when towing you would have to do the same.

[blownba]

You will not have valve issues on gas with the 4.8 if you get a GOOD, weel tuned Injected LPG system.
The main reason why the 4.8 will have problems with valve seat recession is because of incorrect or too lean fuel mixtures when on gas, and this occurs regularly with a old type mixer ring or air valve type gas system.
Vapour injection is a whole new ball game. It recieves a signal from the OEM computer and uses that to inject the LPG vapour, So all the research and development that nissan puts into the programming of their EFI is utilized and emulated with a VSI system.
The way it runs on petrol is exactly the way it'll run on gas. They run so good you'll need to look at the switch to tell if your on gas or petrol. No power loss, perfect starting, and economy only around 7 to 15% more gas usage than petrol, even when towing.
I can't talk up this stuff enough, it really is that good. Try to find someone that has one with injected LPG and go for a drive. You will be amazed.
Spewin your not in VIC cause I could put you on to some of my customers and let them tell you what they think about it. I have not heard anything but praise about all the injected systems I fit.

[PGS 4WD]

The vapour injection is only as good as the person tuning it. Lpg does burn at a higher temperature than petrol even with the tune correct, I have pyroed these, especially when playing turbo gas. Beware how much load the engine is under when maintaining closed loop as combustion temps go up. These are a shim and bucket like the 80 and 100 series cruiser 6cyl and will need more regular adjustment, with the cruisers I always open the exhaust clearance another 2 thou to allow for the extra growth of the exhaust valve when hot.
The search for economy by leaning mixtures under load is a short cut to expensive repair bills.
Lpg is excellent but owners need to be realistic, they now have two fuel systems to maintain, and wear and tear on the ignition system is greater due to the higher voltages required to ignite lpg.
For towing I'd try to find a TD42 and do a few mods as they can easily be improved 20-30 % over std. with no increase in exhaust temps.
Joel

[blownba]

Spot on in alot of respects, if we are talking about older type of gas systems but with our injected system alot of what you are highlighting are not present.
Alot of the injected systems that you get nowadays come with tunes loaded to meet emission certification but it is so important that the tune is checked against the petrol tune. STFT's are the greatest tool used to do this so if you do get injected systems and the place doin it doesn't have a scan tool to monitor fuel trims of the petrol ECU, GO SOMEWHERE ELSE.
The beauty of this type of system is that it will fall out of closed loop under load just like a petrol tune would so you don't have the problem of fuel control or lean out under load or high rpm. Also the system can revert to petrol under extreme load/ rpm as a saftey mechinism to not allow high combustion or exhaust temp. All of this is done seamlessly without you noticing it and as soon as you back off again slightly its back on gas. So in reality the problems you talk about with high load ect are not present with a well mapped system.
I have a few that are running our systems and in peticular one of em has done alot of kays and I have been monitoring valve clearances and so far at the 40,000k mark there has been no decernable valve recession indicated by closed up clearances. The owner insisted on having a valve lubricator fitted when the conversion was done so there may be a chance that it may be helping.

[PGS 4WD]

Yes basically that's what I said, but stoich is stoich and LPG does burn at a higher temp than Petrol, and in order to obtain economy many manufactures operate the vehicles in closed loop at very high loads and this is not good with LPG as combustion temps rise. I am by no means familiar with all the various brands of vapour injection systems, whether the system is old or new if the mixtures are correct for the given load any additional wear and tear on the cylinder head will be minimal, and in reality the cylinder bore will last longer in an LPG engine as fuel wash does not occur(vapour fuel). Additionally the reduced carbon content of LPG makes for less carbon build up in the engine. Unfortunatly the vapour injecion systems I have seen start on petrol and run on petrol untill the engine is warm as they cannot meet the emissions of the warm up cycle, which is a shame as the biggest benefit to your engine is the ability of LPG to run without excessive enricment when on a cold engine, enrichment causes cylinder bore and ring wear due to liquid fuel washing the oil from the bore.
I got out of the LPG game for a number of reasons but one was that there is always someone who will do it cheaper, I saw some real crap over the years, just be sure to go where they sell quality not price as it wil be cheaper in the long run, give blownba a go as he seems passionate and that goes a long way.

Joel

[TEAMRPM]

My old man is contemplating buying a nissan patrol for towing a caravan around aus and any info good or bad would be helpfull.the issue he has is that it was brought to his att that a bloke with a 4.2 overheated and the aircon kept cutting out towing across aus during fairly hot days though a few 3.0td didn't have these issues.though the 3.0td is also a possible option.As i am extremely biased towards the 4.2 (4.2tdi ute), he is thinking of buying a 4.8 and putting it on gas but niether he or i have heard any reviews.please let us know of any thoughts or experience you have had as it will be very helpfull

go turbo diesel 4.2 and LPG that...

now dats what im talkin about..