Vacuum line and LG gas question

Hi guys,

I was elbows deep in my GQ patrols guts yesterday, replacing hoses, filters etc, when I pulled the air filter box off and didn't really pay attention to the whole plethora of vacuum lines running all over the place. One of the two which go up to the air filter box on the driver's side of the carburettor popped off as I lifted the unit. After that, the idle on LPG would drop right down to 300rpm and really struggle. Idle on gas was actually the opposite - around 1200!

I really wouldn't post here asking for help but after trolling through the troll forums, I couldn't come up with any sort of vacuum schematics mentioned a few times here and there - and I can't seem to find answers to all of my questions in the nissan service manual...

After replacing a few hoses, and re-hooking up the automatic temperature control unit (the last bugger had blocked the hose with half a bolt) I did have both LPG and petrol idle back in order, but then after flicking back to LPG, its idling really low again and skipping a lot of beats (only on LP).

So I thought I'd post a photo of the vacuum lines which I am not really sure about, in the hope that someone here can point me in the right direction... I've attached it to this post.

As you can see, there are a number of vacuum lines coming off a splitter 'tree' down there.

Above this tree, blocked from view in the pic, is a single line coming out of the base of the carby, which actually doesnt have any vacuum. The one hose I couldn't logically put into place is the hose coming from the emissions/charcoal canister located at the front of the engine bay. Would that hose go on this single fitting without vacuum?

So my plea is, is there anyone who can correct my wrongs, or tell me where to get the schematic?

As for the strange rough idle on LP since playing with the hoses, I loosened off the air filter box again and made sure the gas ring was properly seated on the carby and snug to the filter box itself. I also replaced the vacuum hose on the passenger side of the carby, which goes from the bottom of the filter box to the carby.

Any tips guys, would be greatly appreciated!

CHeers

Nick

Whats your location mate?

norther suburbs of perth, duncraig to be exact. You're in Vic aren't ya?

cheers

Quote:

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Originally Posted by nick4884

norther suburbs of perth, duncraig to be exact. You're in Vic aren't ya?

cheers

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Yep.... Bugger

I'm in Greenwood mate. I have a 92 TB42E with LPG.
PM me If I can help with a 'look' under the hood......

Simon

Thanks Simon! Don't know if there will be much similar there, as yours has fuel injection! I've got the carby variant! PM me your phone number nonetheless and I'll get in touch. Curious as to how LPG is done with injection anyhow :)

Hi nick,

Sorry mate only just saw this MSG. I'm off to work in the morning (FIFO) till tues. will pm when I return to see if you still need to check out under the hood.

Simon

Would be great Simon. Cheers

Simon's being EFI won't of much use to you Nick

I realised. Thanks to everybody for the initiative. Finally found a TB42 close to me and it ends up I got the vacuum lines ok in the end! I've still got the mysterioso idle problem on LP, I'll post a new thread and hope someone can shed some light on it for me! Cheers

Simon I need help with vac lines and I have the efi 4.2E, I started a thread a while back
http://www.nissanpatrol.com.au/forum...412#post162412
I have had some help, thanks guys, if you do get the chance to take a pic showing where yours go I would appreciate it

marty

And Nick if you are curious how LPG is with EFI I can tell you it runs great, power and economy, its a real smooth change over too......no drain the carbie just click and its changed.....both ways. I have no gas prime but it can start on gas cold. I usually start on petrol though. The startup on gas can ( and has ) resulted in a back fire through the intake ducts destroying the airbox.
I am currently making an alloy airbox and I hope to plumb this to a snorkel later. Hope this answers your question.

marty

Hi Marty,

Checked out your other thread.
I'm at work at the moment. FIFO so 1000k's from my car.
I'll have a look under the hood when I return home (Wed next week) and post some pix....

Simon

Thanks for the offer Simon, be good to get these vaccie hoses back where they should be.
If anyone reading this has a skeematik diagram of vac system on a 92 EFI I would appreciate it.
(An yes I cheat at scrabble)

Hey Marty,

Still need those pics?

Simon