1.6 8v in sierra, rebuild carbi or LPG

[BAD70Y]

Hi there, I am getting the S#$T's with my new engine
I have not long put a 1.6 8v Vitara engine in my 92 Sierra 5speed
had some wiring probs that "Nik" helped me fix
Thank you some much Nik, Greatly Appreciated
(subject) 1.6 auto radiator, 1.6 8v carbi motor, '92 sierra

This engine has a lot more power then the old smoky 1.3 BUT
idle gets stuck at 1500 rpm, I have had trouble with adjusting the idle
(did not touch the mixture, did touch timing as a last resort to get the idle down)
and now it is running rich and the plugs are black with carbon

It uses heaps more petrol then the 1.3

I have a may be silly question
Is the carbi on a auto vitara different to a manual vitara?

And can I get some people opinion's who have gas on their Suzuki
rebuild carbi or go straight lpg

[want33s]

Auto and manual carbies are different and if you put an auto carb on a manual expect it to use shitloads of fuel. Manuals almost always use 'Vacuum Secondries' where as autos use 'Mechanical Secondaries'. Autos have kickdown and need a big gulp of air and fuel to make engine rev when kicked down, A manual will bog down if too much fuel enters. LPG is the go, I reckon, IF you can find room for the tank.

[bru21]

mate buy my feul injection in for sale.

[Gwagensteve]

LPG is for forklifts and BBQ's.

My vote - either put a manual carby on it and live with carby drivability or buy Bru21's EFI, you will never look back and the divability/power will be miles ahead of LPG.

Just my 2C

Steve.

[Santos]

I'd love to see a straight lpg sierra, you could run some serious timing that a petrol or dual fuel could not cope with.
if you plan you trip correctly running out at the wrong spot should not be an issue, good fuel economy much easier to achieve if it's straight gas as it can be tuned for it rather than making trade offs for both fuel and gas.
(even if you used 50% more per 100km you still be paying the equivalent of 75c per litre)

If power wasn't enough then you could resort to a push-button toyota supercharger for power on the fly. This should actually give you a good fuel economy relative to power as the lpg will be 100% gas giving a complete burn (petrol may not evaporate completely)

Unlike petrol carbs, lpg carbs have the ability to always flow the correct ratio because the pressure behind them, petrol carbs start pushing the fuel back up the fuel line.

Other possibilities with the g16a is the run a jimny head with 1mm oversize jimny pistons which would put the compression into the 10:1 vicinity, it would most likely yield the best overal fuel economy for power.
(A 1.6l swift tbi manifold would make a great intake)

Lastly if you could get all the bits cheap you could probably talk to the fitter about it all going on the same invoice to claim as part of the conversion on the rebate. I'd be inclined to get the right shape/ capacity tank new and then go out and source the rest second hand.

[BAD70Y]

Thank you all for your response,
I am going to do some research on the gas $$ and
Bru21 how much do you want for the injection?

so I can work out what my options are

If I go EFI I have a brand new long range tank I will make use of
or
Gas, how big of a tank will fit into/under the Zuki

[want33s]

LPG is for forklifts and BBQ's.

My vote - either put a manual carby on it and live with carby drivability or buy Bru21's EFI, you will never look back and the divability/power will be miles ahead of LPG.

Just my 2C

Steve.

$1.30 for unleaded..... $0.55 for LPG. You might be better off keeping your 2C Steve, you'll need it for petrol.

[BenT]

I'd love to see a straight lpg sierra

I was in China recently, and in the city I was staying in (Chongqing) there are thousands of yellow taxis there that are....... 4 door Suzuki Swifts.

They're built in China and run a G13 with a 16 valve head, and DEDICATED CNG!
http://www.ngvglobal.com/market-develop ... et-14.html

I even had a look round the factory that was making the G13 blocks and cranks


Ben

[bru21]

you can have the jimny motor 13bb, loom, computer (blown bottom end apparently) all inlet gear, air box etc etc for 1k. it will be un molested, tagged, supplied with wiring diagram, air con, alt, etc etc

0402337734

[BenT]

idle gets stuck at 1500 rpm, I have had trouble with adjusting the idle
(did not touch the mixture, did touch timing as a last resort to get the idle down)
and now it is running rich and the plugs are black with carbon

Did you check the butterfly was fully closing by rotating it closed by hand? Maybe too much tension on the throttle cable?

Does the Auto carb have an idle-up vacuum solenoid next to the throttle linkage to increase the idle speed? My 8V TBI engine does, and when hooked up it makes it idle at about 1500 rpm whenever the lights or fan etc are on.
Its a little metal pot with a rod sticking out that pushes the throttle open slightly.

Failing that, if its idling high and the butterflys are shut, have you checked that all your vacuum lines are hooked up and / or you don't have a vacuum leak somewhere? That will bump up the idle a heap.

Ben

[Gwagensteve]

I never said LPG wasn't cheap, but we are talking about sierras here right? I had a '91 rangie converted to LPG some years ago by a very reputable workshop - one of the dearer LPG conversions... all the bells and whistles, dyno tune etc.

It was okay, as it goes, but the range was shot - 275km average, (we travel 130km a day), economy dropped- inevitable on gas, it isn't as thermally efficient, and then it started misbehaving about 4 months after fitment.

Maybe straight gas is the world.... but I remain to be convinced.

Like most of these threads though, the question asked gets a little sidetracked- I don't believe LPG is viable in a sierra for a few reasons, and compared to a good EFI set up, won't be better to drive (but will be cheaper to run) and I don't think it would be worth building a motor for straight gas. unless you were covering a LOT of km's (and you woudln't be doing that on 33 muddies and a SPOA)

get the right carby on it or go EFI.

Just my 75c/l
Steve.

[Santos]

On a side note it amazizes me that people go to great lengths of fabbing and modification of suspension, engine swaps and wiring woes but often baulk at simpler concepts being viable

One cool thing about a straight Gas set up is having the whole 'angle' thing that ppl talk about in efi without the electrics or home grown internal /external fuel pump configurations. On this keeping it simple idea a supercharger set at 5psi gives power when needed and will not 'lean out' which is an issue with tuning efi sistems and is less likely to ping itself to death on account of the higher octane

Steve: was the rangie straight gas? How big was the lpg tank and exactly how much cc did it displace over 1600cc of a vit 8v? How much did it weigh over a sierra? One of the reasons diesel, lpg an ethanol lose out in the fuel debate is comparisons are often drawn on engine configurations that favour petrol conditions but if the engine is set up to conditions of alternative fuel it generally performs just as well if not superior to petrol, why i keep saying 'straight gas' as opposed to duel fuel.

BAD7oy - a good out of print book for background research is 'propane Conversions' by SA Publishing it talks about pro's and cons of straight or dual-fuel configurations and gives you an understanding of options in instalation. i would stick to the simpler carb set ups rather then going for new age injector set ups. (be cool to see a twin or quad forklift carb set up )

As for which tank fits pull out the tape measure, i am guessing trade Van would have the right shape ones for a sierra. Or else maybe a doughnut
shaped tank that are designed to fit in place of the spare in falcons and commodores.

The rule they have in brazil is 80% of the gas in the tank is usable. So just work back from there. Let say you get the worst economy of 15l per 100km whinch equals 6.7km per litre, then 60l lpg tank would give you 48l (80%) x 6.7 = 320km range ($26.40 @55c/L) If you want a bigger range, bigger tank.

I'm however betting that you could get it to 13l per 100km area which would be in the vicinty of 7.5kms per litre giving a 360km range. Unless you are crossing the desert spending a little extra time planning you trips and stops lpg is not a problem all along the east coast.

If not jump in the new project craze and build a long range trailer complete with 120l tank which acts as a refilling station.

[BAD70Y]

Hi there

want33s, I greatly appreciate telling me the difference between the auto carbi and manual carbi and your opinion

Ben, I mucked around with the "solenoid next to the throttle linkage to increase the idle speed" and the idle up for lights etc is wired up correct big thanks to Nik, but over all it is not running quite right

Steve, your 2c is greatly appreciated! I spoke to a lpg mechanic today, He's opinion was to stay with petrol as fitting a decent size tank would take up too much room in/under sierra to go straight gas. (LWB sierra would be no probs)
EFI would be Good! but I should be using a swell pot with it ,they can be costly
His easy opinion is get the right carbi for it.

this mechanic was very helpful and friendly,
NORTH PARRAMATTA, PNC Automotive Services, Cnr Bourke & Hunt Sts 2151

Santos, for me I prefer simple when it comes the the engine in a 4x4, it should be one of the last things to worry about and if something does do wrong it should be easy to fix.
But I do have to consider Bru21 efi

Bru21, the efi does sound good!

Questions now
I have a never used long range tank, I think it is 70L so I could modify it
swell pot/tank, is it easy to make one or get from another car to save money

and Jimny efi on a 1.6 problems will it bolt on with out any dramas
could I bolt the Jimny head onto the 1.6L

Thanks, Aaron

[bru21]

i know i am selling the gear, but i find it hard to believe it would run lean. the injectors have a cycle time that is increased if there is a lean out in response to o2 sensor. If you were to turbo a jimny the std injectors should be fine for say 30% more power output. so a capasity increase of .3 lt is about 20 % should be fine. there may be an issue i am not aware of specifically so this is only my opinion

cheers bru

[NIK]

No worries Aaron
But Im having the same probs using heaps of fuel!! I thought maybe it was because its doing 4000rpm at 85km/h but even low speeds its using alot more fuel than a 1300.
I got a rough quote to rebuild the carb, worst case $450 fully tuned on the car. Now I know that was worst case but $450 is alot of money to a zooker so I bought the kit for $75 and had ago myself last night
Yep I wasnt paying attention when I undone the linkages on the throttle body So now I have to find another one to see how it goes back together
Mine to is an auto carby and a mechanic that looked at it said it was definatley over fueling as there was misting in the carb after the motor was shut off.
On a side note has anyone had any sucsess removing the plastic needle seat that the float swivels on?
Nik

[BAD70Y]

I rang around to find a carbi off a manual vitar, but could not find one.
took the carbi off to have a better look at it, I adjusted the choke butterfly to make sure it would not get stuck and adjusted the idle were it cones in contact with the solenoid with try and get some pics up soon.
Also adjusted timing, the zook is idling at 900 rpm.
the oil filler cap was a little milky so I put some chemi-weld in the radiator
The zook is running better but not sure if it is using much less petrol

[smileysmoke]

being an 8v have you thought about getting tbi for it? or even a weber?
glad to hear its running a bit better though.

[NIK]

I spoke to a mechanic today and he said he has never heard of autos and manuals having different carbs. I showed him mine (off an auto) and he pointed out it cant be right as mine has vacuum secondaries.

My opinion dont go the webber. I tried for ages and couldnt get it right, yes it goes hard but can it run on angles or down STEEP hills I know my standard carb can
Nik

[NIK]

How did you go Aaron?
Just a thought the other two wires going to the carb that we didnt use are they for a fuel cut off solenoid? Would this change things
Nik

[BAD70Y]

Hi Nik, the zook is running better and using less petrol and idling well 1000 rpm
( I may be pointing out the obvious so please forgive me if so)
the blue arrow is the idle screw
The red arrow this adjuster was stopping the throttle from going back, it was pressing against the solenoid
so once I adjusted both of these screws I got it to idle better, but still need to adjust the timing a little more. It has a slight dead spot at 1200-1500 rpm

hope this helps a bit

[NIK]

Yeah I think Ive got them right my best mate is a mechanic and he hooked it up to his computer thingy but he said its still over fueling. So I was thinking those extra two wires on the carb must be there for a reason just not sure what come on I cant know everything
thats why we have girlfriends!
Nik

[BAD70Y]

When you find out what the other 2 wires are for let me know.
Yep my girl Johanna, she amazes me with her worldly knowledge

[NIK]

Had a look through the workshop manual but it didnt seem to have a vit carby, hopefuly someone on here might know what the wires going to the carb are for.
Nik

[BAD70Y]

My zook book is the same, not much help
(Haynes suzki sj & vitara 1992 to 1997)

[NIK]

Took it to the beach on sunday after I rebuilt the carb. Dosnt go any better but I think it used less fuel. It did run on a bit though, I was cruising to a stop up a slight hill and just turned the key off while driving (foot off the acelerator) It stopped then rolled back and fired a few times going backwards with the zook still in first!
Nik