New Patrol owner.

[sfrrob]

Hi guys, I am new around here and have some newb questions for you guys.

I have recently purchased an auto 1990 GQ patrol ST 4.2 Unleaded/Lpg wagon.
I have a few questions regarding the longevity of engine components, especially when it is running LPG.
It has low 200,000km on the clock and seems to run well, idle is a bit low on petrol when in gear but runs ok on both fuels but, it is incredibly slow..... I came out of a worked FPV F6 ute and F6X Territory so it is quite a system shock when you put the foot down and you aren't pushed back into the seat like the last 2 cars I owned.
My old man bought a 1990 Maverick brand new and I recall that going quite well, it is specced exactly like my GQ sans LPG.
Would it be a case of it just being a bit tired and it being tuned to run LPG?
Would you recommend getting rid of the LPG system entirely and getting the car tuned to run straight unleaded?
I was also wondering what I need to keep my eye out for in regards to these engines. What are common components that fail, what preventative measures can I take to keep the car running well, and for a long(ish) time.

Also, I want to fit 33 inch tyres to the standard rims but the car is at standard height. I will only be doing "soft off roading" for the time being so I really don't need a body or suspension lift... OR WILL I have to lift to fit the 33's?
I am sure I have seen a standard height Patrol with 33's on it.

[threedogs]

Hi Mate and welcome to the forum, as for the gas system Me I would
throw it,, causes too many problems ,and gas being the price it is just out of town
I dont thnk its economical enough to run, If you only do short trips it may be ok, thats your call
Without a valve saver fluid system on the motor you may already have valve recession , get a compression test done
it see how your motor is going,
You can only really tune either gas or petrol on the older systems most go for gas.
Strip out the gas put a kit through the carby and start again VVVRRROOooommmmmmmmm
May need a 2" lift to run 33"s but the GQ boys would know more

[Stropp]

hi mate and welcome to the forum.

[4bye4]

G'day mate and welcome to the forum.

[Clunk]

welcome aboard mate, the TB42 should have a little bit of get up and go but you shouldnt expect to be thrown into the back of your seat like your ute and territory. If you're not worried about fuel consumption, I'd also ditch the gas system, I'm also not a big fan of them.

33s will run fine on an unlifted GQ, especially if you're not going to be doing much offroading, just get 10" wide though as you'll find that the 12.5"wide will probably scrub on your front mudflaps on lock to lock.

As Threedogs said, get a compression test done to give you an idea of how th engine is doing. They're fairly bullet proof but heads have been known to crack.......... mine just went at 217000K :(

[sfrrob]

Cheers fellas.
Yeah, I will rip the LPG system out, and will suss out the . NEVER been a fan of them.
Regarding the 33's what brands are the go? I have no idea!
Thanks for the quick responses too!

[Stropp]

i have hankooks, they are a good tyre but you will get lots of different advice, just go with what you like in a name brand.

[MEGOMONSTER]

Welcome mate, surely the best forum on the net. If you need it, you can get it, if you want to know it, just ask it.
If you want to find it, go to the search bar for a universe of information.
Enjoy the sights and sounds of the greatest show on earth.

[GQ TANK]

As standard the tb42s wont slam you into the seat but you are talking about a heavy 4wd. Dependant on your pocket pull the lpg - if the truck is running well leave it alone. If you want a patrol that will go a lot like a car consider a TB48 in the latter gu's, we had them at work and they had heaps of power - and a lot thierster then the tb42.

The gq is designed as a work hourse with great off road capabilty.


If you want to know what it will be like on petrol, flick it back to petrol and turn your dissy back to around 10 degrees

[sfrrob]

Hi guys, forgot where I posted this thread, obviously I found it again...
I took the GQ for my first drive since I picked it up. It got to about 3/4 on the temp gauge in heavy traffic on my way home.
It felt REALLY hot under the bonnet and my interior fans were blowing hot air.
I stopped to put some air in the tyres and could hear a bubbling, popped bonnet and noticed the resvoir/overflow for coolant was boiling away and expelling steam out of one of the breathers. I wasn't giving the car a hard time AT ALL.
So I parked it, bought a new radiator cap and topped up the coolant. (2.5L !!)
Started the car and drove for 1.5 hours, temp fluctuated between half to 3/4 then it started to come down and hover just under half to right on half at 100kmh.
Mid trip I stopped and didn't hear any boiling and the temp was just under half, the reservoir how ever was almost full of coolant (above MAX) but I continued on my journey.
Pop the bonnet the following day and the coolant reservoir was showing just above MIN. I remember reading somewhere that as the engine cools it draws the coolant back into the block under vacuum.
The following day I took it off road, very tame off road tracks in fact.
Anyway the temp stayed at 1/4 - 1/2 ALL day, even when I gave it curry through some sandy sections.
Anyway, over heating issue seems to have sorted it's self out.
I am only guessing as I'm pretty mechanically retarded that it was either a crappy thermostat, air lock in the radiator that worked its way out or the fact that the car probably sat around in the car yard for quite some time before I bought it and that had something to do with it.

Now, the power from the car is woeful, it just doesn't feel right, I know it's a 20+ year old car, lpg, heavy etc but i expected a little bit more grunt.
The car has had new leads installed (they look new anyway) and i can see the head gasket looks pretty fresh and the head bolts look like they've recently been played with.

I'm really entertaining the idea of dropping an i6 barra turbo in it from the falcons. Not sure if it would be possible with an auto transmission.
Anyway, I will come back and edit this post later, didn't get a chance to proof read as I am "watching a movie" with the Mrs and kid.

[mudbug]

i to had same issues you have but after spending big dollars chasing power and economy i ended up getting a low km tb45 and i put tb42 rods in it freshened up the rest stuck a gt3582 on the side recond the trany with a shift kit put a manual lockup switch on it and i now have a more powerful and better economy and heaps of fun off rd dont spend big dollars on the standard tb42 you won't gain much they go hard with a turbo on it i was just lucky to come across a tb45 with low km and cheap you may need a lift kit with 33 i did but my suspention was a little sad when i bought it .
good luck
cheers

[growler2058]

Gday mate welcome aboard

[sfrrob]

Still deciding on what to do.
Maybe I will just chuck a rebuild kit through it and turbo it.
Just scared of the head gasket and warped head these are renowned for.
I don't want to spend too much coin on it but realistically with modding and looking for more HP comes $.

[vizirucostinel]

welcome to the forum!
-new owner of a patrol here, too-

[sfrrob]

Ok so really had a gut full of the current tb42 in the car. It's developed an oil leak somewhere, found a small puddle of fuel under the car when I moved it out of the garage. The smell of fuel is very strong. I noticed the smell after flicking it over to petrol from LPG for a few minutes.

What do you guys recommend. I've got the choice between 2 turbos o can get my hands on at a good price.
One is a t04z and the other is gt25.
Has anyone turbo'd their carby tb42 and which turbo would you go with?

[Dhuck]

Welcome to the forum mate.

[sfrrob]

Been looking around, why can't I drop a Rb30 from a VL turbo into the GQ?

[Winnie]

Been looking around, why can't I drop a Rb30 from a VL turbo into the GQ?

You certainly can, GQs came from factory with the RB30 in them

[sfrrob]

Hey Winnie, cheers for that bit of info. I am a bit green when it comes to the Patrols so I wasn't aware.
Would I still be able to run the factory AUTO transmission?
I have been looking at blow through turbo setups and it seems the easiest way to go at the moment. I don't want to convert it to EFI if I keep the TB42.
I reckon I could get away with a freshen up (rebuild kit) and an intercooled turbo setup for under $3k going blow through.
There is a green patrol ute on the other forum (can't sign up there for some reason....) and that has the exact setup I want. username of the guy is snapper trapper.57045
If I were to go Turbo RB30, what would that be worth?