[S13RR4]

JrZook wrote:

S13RR4 wrote:

what are peoples thoughts on vitara carbies?

is the jetting on vitara carbs better?

are they much better then sierra carb?

which would be better option>
a) rebuild sierra with bigger jets?
b) vitara carb (possibly rebuild to make a level playing field)

joe

Dude overall what are you looking for from a carb?

reliable, functional and economical..... and cost effective...

just wanting to look into it a bit more and get the best result first time.

[S13RR4]

Teracis wrote:

S13RR4 wrote:

Teracis wrote:

I've got the transfer out of mine atm putting gears in tomorrow, but maybe next weekend I'll rebuild the carby, I've had the rebuild kit for a while and while I'm confident to rebuild the thing myself, it's the tuning that I'm worried about, it's so easy to stuff up. Might do some research as to a standard "wind the screw all the way in then back out two and a half turns" type instruction that works and use that?

when you say rebuild kit...

whats included in the kit?

I'm not sure exactly what is in the kit, there's heaps of stuff, I'll let you know when I've done it, but things I do know: All the gaskets for a rebuild, new accelerator pump plunger, new needle, no jets or anything you just clean those.

Also, you're better off rebuilding the sierra carb as far as I've read. If you can set it up right it's the best one for the 1.3 bar the fuel injection.

thanks mate, I think I'm starting to sway towards this option

[Rusho]

I got my carb professionally rebuilt close to 2 and a half years ago, took it off the car handed it to someone who knew his stuff, set it up to what he thought would be close, drove it back to him for a final tune and check timing etc. Has NEVER missed a beat since. As far as jetting goes....nit really worth it in a stock form. Let it be. JMO

[Teracis]

So I rebuilt my carby, everything I could get at bar pullling the butterflies and their shafts out (as there was no play in them and I didn't want to pull all the stuff off the side

Long story short, it still has that massive flat spot just above idle. If you are on the pedal, come off for a little bit, and go back on, it dies and then revs out. Really annoying and I'm not sure exactly what's causing it, apart from possibly a short term lack of fuel as you stand on the pedal?

It doesn't always happen, which is even harder to work out.

[Rusho]

Refer to my above thoughts

[Teracis]

Rusho wrote:

Refer to my above thoughts

I'll go one better, instead of spending the afternoon trying to get it to work without all the info, I'm going to work out what it would cost to put an injected 1.3 in

[royce]

Teracis wrote:

So I rebuilt my carby, everything I could get at bar pullling the butterflies and their shafts out (as there was no play in them and I didn't want to pull all the stuff off the side

Long story short, it still has that massive flat spot just above idle. If you are on the pedal, come off for a little bit, and go back on, it dies and then revs out. Really annoying and I'm not sure exactly what's causing it, apart from possibly a short term lack of fuel as you stand on the pedal?

It doesn't always happen, which is even harder to work out.

Did you lose the little ball check in the bottom of the accelerator pump chamber?

[Teracis]

royce wrote:

Teracis wrote:

So I rebuilt my carby, everything I could get at bar pullling the butterflies and their shafts out (as there was no play in them and I didn't want to pull all the stuff off the side

Long story short, it still has that massive flat spot just above idle. If you are on the pedal, come off for a little bit, and go back on, it dies and then revs out. Really annoying and I'm not sure exactly what's causing it, apart from possibly a short term lack of fuel as you stand on the pedal?

It doesn't always happen, which is even harder to work out.

Did you lose the little ball check in the bottom of the accelerator pump chamber?

Nope, I made sure that was in there, the accelerator pump seems to be working fine, it shoots fuel out when you work the accelerator. It doesn't shoot a great deal of fuel though, and it's more of a squirt, it's not really atomised, is it supposed to be?

[Teracis]

Oh and to be able to turn the idle mixture screw I used the dremel to cut a slot in the end of it, special tool pfft!

[Rusho]

Teracis wrote:

Rusho wrote:

Refer to my above thoughts

I'll go one better, instead of spending the afternoon trying to get it to work without all the info, I'm going to work out what it would cost to put an injected 1.3 in

I like your style

[royce]

Teracis wrote:

royce wrote:

Teracis wrote:

So I rebuilt my carby, everything I could get at bar pullling the butterflies and their shafts out (as there was no play in them and I didn't want to pull all the stuff off the side

Long story short, it still has that massive flat spot just above idle. If you are on the pedal, come off for a little bit, and go back on, it dies and then revs out. Really annoying and I'm not sure exactly what's causing it, apart from possibly a short term lack of fuel as you stand on the pedal?

It doesn't always happen, which is even harder to work out.

Did you lose the little ball check in the bottom of the accelerator pump chamber?

Nope, I made sure that was in there, the accelerator pump seems to be working fine, it shoots fuel out when you work the accelerator. It doesn't shoot a great deal of fuel though, and it's more of a squirt, it's not really atomised, is it supposed to be?

Make the arm that pushes the plunger a bit of a firmer fit, so it pushes the plunger sooner, should clear up your problem

[Teracis]

True, I wondered if the HUGE amount of play in that arm had anything to do with it, I'll go scavenge some washers and get the thing sturdy as, I'll report back here as soon as I've test run it.

P.S. Royce If it fixes it I'll shout you a beer if I ever make it to an AZ meet or something :p

[royce]

I think you can bend the big long arm

Dont thank me, nissvit figured that one out, its in a thread in good tech

[Teracis]

royce wrote:

I think you can bend the big long arm

Dont thank me, nissvit figured that one out, its in a thread in good tech

True, I'll go searching again, a few of my search terms turned up nothing.

Also, bad news, it didn't work, I couldn't get anything to tighten the arm on the spindle without locking it up.

So I bent the push rod that pushes up on the lever arm (didn't want to try bending the lever arm due to the way it's shaped.

Mixed results, I put the accelerator pump WAY out of spec (spec says 3.8-4.4mm or something of travel) I had it going like 15 to get a decent amount of fuel happening, think I might have had too much so backed it off to around 6-8mm

Going to read good tech to see what's happening with it.

[royce]

if 15 works, screw the book

you want it to squirt earlier, not necessarily more

[Teracis]

royce wrote:

if 15 works, screw the book

you want it to squirt earlier, not necessarily more

I can't work out how to get it to squirt earlier though because it's attached and the whole thing moves at the same time, as soon as you start to move the cam the accelerator cable pulls, the linkage and lever arm start to move and the piston starts to move. This is why I thought I might need more of a pump, I'll have to do more research.

I'd still like to know what a g13BB would be worth though, surely it would be a set and forget type of affair where once I'd done the conversion I'd have no more trouble for a looong time.

[royce]

when you mash the pedal there is a delay getting the fuel in mainly cause of that spring, whilst teh air is already going in so leans out

bending means you spend less time waiting for the spring to get tension and push the plunger

[Teracis]

royce wrote:

when you mash the pedal there is a delay getting the fuel in mainly cause of that spring, whilst teh air is already going in so leans out

bending means you spend less time waiting for the spring to get tension and push the plunger

Yeh I see what you're saying, I was thinking it could be the fact that mashing the pedal would be a far quicker actuation than just me turning it by hand.

I need the someone else here to sit in and mash the pedal while I have a look at how much lag there is on the pump. I think the easiest fix will be to throw a couple of washers or nuts or something on the linkage with the spring to compress it more and therefore pre-tension it so it actuates the plunger better/quicker/earlier as you say.

I haven't found that thread you were talking about where they talk about bending the lever arm, the way it's made basically says to me it shouldn't be bent, at least not up and down the way I need it to be.

[steak_knife]

Teracis wrote:

I haven't found that thread you were talking about where they talk about bending the lever arm, the way it's made basically says to me it shouldn't be bent, at least not up and down the way I need it to be.

http://auszookers.com/index.php?name=Fo ... pic&t=4160

This one??

[Teracis]

steak_knife wrote:

Teracis wrote:

I haven't found that thread you were talking about where they talk about bending the lever arm, the way it's made basically says to me it shouldn't be bent, at least not up and down the way I need it to be.

http://auszookers.com/index.php?name=Fo ... pic&t=4160

This one??

Read that one, nothing about bending rods or levers, only re-jetting the carby, still bloody good info though!

[Teracis]

Okay so I tried my idea of putting a spacer (read NUT) on the push rod.

One nut basically halved the lag time between pedal stomp and engine revving (when under load)

Second nut has nearly eliminated it, it still does it a bit, but it's far more drive able now, less kissing the windscreen and then snapping the head back.

Next issue is that it starves out after a short time above 4000 rpm, I'm guessing that the fuel pump is on the way out/stuffed so I'll need a new one of those now...

You can hold the foot down and it starves the engine and drops right down with no power, or you can back off and let the float bowl fill back up and you can drive again... I'll need to fix it before I have to go highway driving again...

[royce]

do your filters and hoses first, check your float level as well

[Che]

I have Teracis's problem of an ugly spot just beyond idle too. It'll idle at 1000RPM happily all day, if I try to push for say 1050 - 1200RPM the idle gets real ugly and irregular. Not sure if it's fixable or a carb quirk I have to live with.

I run straight LPG so fuel comes in via the mixer ring sitting on top of the carby and not the carbs jets, carb is a throttle body only. All is well sealed with a dab of oil on all gaskets to stop fine leaks, and vacuum lines all seem OK with a quick visual.

Any ideas?

[steak_knife]

che_guitarra wrote:

I have Teracis's problem of an ugly spot just beyond idle too. It'll idle at 1000RPM happily all day, if I try to push for say 1050 - 1200RPM the idle gets real ugly and irregular. Not sure if it's fixable or a carb quirk I have to live with.

I run straight LPG so fuel comes in via the mixer ring sitting on top of the carby and not the carbs jets, carb is a throttle body only. All is well sealed with a dab of oil on all gaskets to stop fine leaks, and vacuum lines all seem OK with a quick visual.

Any ideas?

Check your vacuum advance is working..

[Teracis]

royce wrote:

do your filters and hoses first, check your float level as well

I only just set up the float level when I rebuilt the carby, set it up to the manual of 7mm.

Thing is I need it to work properly by friday, might drop in to one stop suzi shop thisavo to get hoses, filter and price a fuel pump...

[Che]

steak_knife wrote:

che_guitarra wrote:

I have Teracis's problem of an ugly spot just beyond idle too. It'll idle at 1000RPM happily all day, if I try to push for say 1050 - 1200RPM the idle gets real ugly and irregular. Not sure if it's fixable or a carb quirk I have to live with.

I run straight LPG so fuel comes in via the mixer ring sitting on top of the carby and not the carbs jets, carb is a throttle body only. All is well sealed with a dab of oil on all gaskets to stop fine leaks, and vacuum lines all seem OK with a quick visual.

Any ideas?

Check your vacuum advance is working..

That's the UFO shaped thing on the side of the carby right?

[Teracis]

Nah the one on the side of the dizzy I think