Topic: H8PVMNT Wrestles a Weber

[H8PVMNT]

Don't everybody freak out, but after learning a bit about tuning with the Aisan 22R carb and getting it to really wake up I just had to try one of these.  My main motivation is the rather porky fuel economy of my performance tuned Aisan carb and reports of similar performance with superior fuel economy from the Weber 32/36.

I had some "truck money" from selling off a few things and some cash left over from my delivery/handling fee from finding a home for a stray 3RZ (thanks Mudder, this is where your money went ), so I though I would use it for something interesting that might pay off in fuel savings over time.

I was sorely tempted to try a 38 synchronous, but taking into consideration Glenn's (79coyotefrg) experiences and others I decided the best choice for this vehicle was the 32/36.  After switching the Aisan carb over to a manual choke and liking it, I chose to use a manual choke on this carb too.

Bought it from these guys  http://www.carburetion.com/index.htm  and it appears to be the "real Weber" with all the right markings and the "made in spain".  They ship really fast and it was a better deal than a lot of places.

Like my Aisan carb thread, I don't want to get into a Aisan carb vs. Weber discussion and why one or the other sucks.  We have all read the horror stories of people who have had bad experiences with the Weber as well as people who seem to do great.

One thing is for sure you can really tune the Weber from all sorts of directions, with so many different jets and air correctors available I should stay busy on my lunch break for the next few months!

So my goals are:

1) To see what these Weber carbs are all about and learn to tune them.

2) To make one work off road at bad angles, if possible.

3) To achieve similar performance as my tweaked up Aisan carb, but with better fuel economy.

4) Get the winter sub zero cold start with the Weber (time will tell). 

5) Document my experiences for the benefit of everybody else.


If I end up hating this thing I will either sell it off or use it on a less off-roady application.  If I like it, it will stay where it's at.


Here it is, love it or hate it...

[emsvitil]

 


 

[H8PVMNT [OP]]

What do we do with a brand new carb?  Why take it apart of course!

What was odd though is that I didn't have to soak it in solvent or heat anything with a torch to get it apart.  Voided warrantee or not, before this thing is allowed anywhere near my 4Runner it had to get the "hill climb mod".

It's been done and is all over the internet, but you simply fill the bowl vent with JB Weld and then drill some holes in an unused port and stick a bit of 3/8 copper tube in the port so you can vent the bowl.

I also adjusted the float to the recommended off road settings.

No flippin' wonder these things can't climb a hill!  Not only is the bowl vent right at the back of the bowl, it also dumps fuel right into the air correctors when you go steep!

The offending vent...

[OVRAROK]

 

[fireitup]

YEEEEHAAA

  

[H8PVMNT [OP]]

Here is the goob being stuffed in the bowl vent.  I taped up the bottom so it wouldn't get to messy in the float bowl.

[H8PVMNT [OP]]

The deed is done!

[OVRAROK]

soooo, now ill we do is wait 

[H8PVMNT [OP]]

soooo, now ill we do is wait 

Care to place any bets amongst yourselves as to how long this thing stays on my engine? 

[OVRAROK]

 

[H8PVMNT [OP]]

I am running a 20R head and intake.  I couldn't find a one piece adapter for anything but the 22r intake so I will be using the dreaded 2 piece adapter.  I used grease on the gaskets because I like to take things on and off my truck a lot.  I have been running this all ready as I write this and it doesn't leak yet.  Passed the carb cleaner spray the adapter gaskets test  .

Note the little barb fitting for the PCV hose that goes on the EGR spot.  I am happy to report far less puking of oil through the front breather in the valve cover with this setup.  The LC 22R carb to 20R intake adapter I was using has just a little groove for this and must not be adequate for PCV because the pressure tends to take the path of least resistance and sends a big mess out the front breather rather than through the PVC valve.  I will use this piece even if I put the Aisan carb back on for winter.

[H8PVMNT [OP]]

You get the adapter on and then you get all excited and bolt your carb down only to find the throttle no longer opens.  There is this tab that has a clearance issue with the adapter plate.  I trimmed a bit of it off carefully with the side grinder, with some cardboard taped to the carb mounting surface so not to nick it.  You don't want to take too much of it off because the tab is a throttle stop and still needs to bottom out on a flat spot in the casting. Cleaned it with a file and now it clears the adapter.

[H8PVMNT [OP]]

After reading many, many, many bad stories about the cheapo fuel pressure regulators I decided to wait a couple weeks, return some unopened paint, sell a couple things and order up a nice redline regulator with a gauge.  The best part is this one is OK for ethanol blends, which some of the other middle of the road ones aren't.  Goes along with my carb setup doctrine to tune for the fuel, not fuel for the tune.

The gauge dances around a bit but settles out enough to get a good reading if you work the throttle a bit.  On this regulator you tighten the allen head adjuster for more pressure and back it out for less, which is contrary to what the tech guys said  .

I initially had it set for like 2 psi, now I have it a about 3.5 and it seems to like it better, but I'm sure I will revisit that later.

[H8PVMNT [OP]]

There it is.  I've all ready re-jetted once and sorted out a surprise pre-existing issue, but I'll save that for next weeks installment.  Stay tuned for more tune.   

[THK Matt]

[Mudder]

I'm excited to see this. It'll be nice to get a real comparison even if it does mean reading two different threads.

[Gnarly4X]

I can hardly wait for this thread to develop.

H8PVMNT,

I have a couple thoughts...

First, if you do not have an AF gauge, and even if you do, I would start with a brand new set of spark plugs to get a fresh reading.

Who's fuel pump is installed?  How many miles on it?

What octane gas are running now?  And I assume you are filling up the tank from the same filling station?

I ran Webers for about 8 years on my sand rails.  One thing was very clear to me is that they like REALLY clean air and REALLY clean fuel.  I would make sure my air filters are very clean and fresh and I would have a fresh fuel filter installed.  On my sandrails I ran 2 in-line fuel filters.  My K&Ns (don't ask me about my experience with K&N air filters) were cleaned and fresh every trip to the dunes and meticulously installed onto the carb.

You probably won't have to worry about the sand issue where you are, but I am just passing on some information from my experience in the past.  I averaged 18 trips to the sand dunes every year, so you get an idea of my level of "off-road" activity during my duning days.

Gnarls.

[Gillesdetrail]

I'm also in the middle of retuning my weber 38 now that I have a wideband sensor and gauge. What I thought was a timing issue turns out that I am running below 9.0:1 (pig rich) under 3500rpms at full throttle.

I have:

45 idle jets
f6 emulsion tubes (stock came with f50 just like yours)
170 air correctors
145 mains
float level: 18&28mm
Around 1 turn out on mixture screws

On the highway I'm right at 14.7:1, part throttle up to 15.5:1, idle close to 14:1, averaging 23.5 mpg (10l/100k) and drives really smooth, but wide open throttle is pig rich below 4k. I have 140 mains coming in next week. If you have any questions hit me up, I'm starting to get pretty familiar with these. One of the best source of information about these carbs on the net is here: http://www.jeepforum.com/forum/f8/weber-set-up-tune-discussion-1051137/
A long read but a lot of good info.
Also, I am running a weber to 20r manifold adapter from transdapt, it is a good quality piece. And remeber webers like more timing (8-10*).

[H8PVMNT [OP]]

I can hardly wait for this thread to develop.

H8PVMNT,

I have a couple thoughts...

First, if you do not have an AF gauge, and even if you do, I would start with a brand new set of spark plugs to get a fresh reading.

Who's fuel pump is installed?  How many miles on it?

What octane gas are running now?  And I assume you are filling up the tank from the same filling station?

I ran Webers for about 8 years on my sand rails.  One thing was very clear to me is that they like REALLY clean air and REALLY clean fuel.  I would make sure my air filters are very clean and fresh and I would have a fresh fuel filter installed.  On my sandrails I ran 2 in-line fuel filters.  My K&Ns (don't ask me about my experience with K&N air filters) were cleaned and fresh every trip to the dunes and meticulously installed onto the carb.

You probably won't have to worry about the sand issue where you are, but I am just passing on some information from my experience in the past.  I averaged 18 trips to the sand dunes every year, so you get an idea of my level of "off-road" activity during my duning days.

Gnarls.

1) Yes I put new plugs in to get a fresh read.  I will be getting an AF gauge in a pay period of two .

2) Toyotas own mechanical fuel pump, after going through 4 aftermarket ones.  This one has about 18,000 miles on it.

3) I am filling at the same pump, 87 octane 10% ethanol garbage.

[H8PVMNT [OP]]

Out of the box my Weber 32/36 is jetted like this:

IDLE JETS:   PRIMARY      -55
                       SECONDARY-50

MAIN JETS:  PRIMARY      -140
                       SECONDARY-135

AIR CORRECTOR JETS:      PRIMARY      -165
                       SECONDARY -160

Following the weber instructions with 1 1/2 turn into the idle speed screw and 2 turns out on the idle mixture screw it fired right up, however my "Lean Best Idle" was at only 1/2 turn out on the idle mixture screw, which indicated a hugely rich idle jet.  It also had a pretty bad hesitation tipping into the throttle from a stop sign.

I then went one step leaner on everything.  My second setup was like this:

IDLE JETS:   PRIMARY      -50
                       SECONDARY-45


MAIN JETS:  PRIMARY      -135
                       SECONDARY-130



AIR CORRECTOR JETS:      PRIMARY      -180
                       SECONDARY -175

This got me "Lean Best Idle" at 1 1/4 turn on the idle mixture screw, which indicated still slightly rich on the idle jet. Still had the hesitation at tip in but now it wouldn't even stay idling when rolling to a stop. It also wanted to ping a bit pulling hills with these jets. I pulled back my timing advance a bit fro 8* to 5* and the pinging stopped.

This was all the jets I had at the time so I started looking for other things.  It passed the base gasket vac leak test with carb cleaner.  I started messing with other things and found when I unhooked the manifold vac line to my #2 charcoal canister, which was hooked to the new "hill climb" bowl vent, it ran better!  So for some reason I was getting some raw fuel sucked right from the bowl, into the manifold through the charcoal canister.  I took the vac off the charcoal canister, left the bowl vent hooked up and no more hesitation.  Messing with #1 charcoal canister, the one from the tank, did nothing so that one is not causing any grief.  "Lean Best Idle" then indicated on the lean end of all right, so I decided to put the jets back to "out of the box" for a fresh baseline.

"Lean Best Idle" is now at 1 3/4-1 7/8 turns out, which is right in the rich end of the pocket.  Having found my unexpected issue, now I can actually tune.  More jets are waiting in the mail box .  Timing advance is back to 8* and no ping.

So I have learned to look for the stupid stuff, because these things will NOT RUN RIGHT AT ALL if there is anything going on in the way of a vac leak or extra fuel, whatever.

Initial impression, I hate to make comparisons, but it's the only way at this point; this thing makes more mid range torque, than my Aisan.  Right at 2,800-3,200, noticeably more pull.  It's too early to say anything though because I have not dialed it in.

Likes to idle nice and smooth at about 750 RPMs with the idle speed screw set to the recommended 1 1/2 turn in.  This is a little lower than I like my "winter tune" on the Aisan carb for the cold start, but when I engage the manual choke to about 1/2 it pops the primary open enough to get a 1200 RPM fast idle so that should work for warm ups.

Oh yeah I picked up 2 MPG so far while running poorly and not really tuned  .

The tweaked up Aisan had a bit more top end and maybe a bit more bounce off the bottom of the tach bottom end.  I find myself less on the gas when accelerating, more happens on the primary on the Weber than the Aisan.  The Aisan seconrary hits sooner and harder (not in stock trim mind you).  I discovered I had a slight lean buck happening on the Aisan at the transition point that has disappeared with the Weber.

The offending EVAP canister...

[emsvitil]

Maybe the canister was affecting the Aisan carb too.................

[H8PVMNT [OP]]

Maybe the canister was affecting the Aisan carb too.................

That's what I was thinking.  You know I'm going to have to switch back over at some point just to see if that's what was causing the horrid gas mileage.

[H8PVMNT [OP]]

I want one of these:  https://www.amazon.com/gp/product/B00N3VGPYS/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A15DTMM40CG6VX

It will be a couple paydays and maybe sell something .

[63W]

Some good info here. My wife's rig is running the same set up so I'm interested in seeing the outcome.


Sent from my iPhone using Tapatalk

[300k]

I can't wait till I can build a proper cluster for "other" readings. oil temp and pressure, coolant temp, maybe vacuum, A/F...so expensive though.

[H8PVMNT [OP]]

After doing to much change at once a few more times, I put everything back to box spec and messed with only the primary idle jet. Man, you sure need to do only one change at a time! 

If you do more everything goes haywire and you can't tell why.  I had swapped to some leaner air correctors when I was changing the primary main and I got a major huff, buck, snort, lean at the upper rpm of the primary.  I immediately swapped that back.

I ended up with the "lean best idle" at 2 1/8 turns out with a 50 idle jet.  That's right on the lean end of OK.  The 55 jet put me right on the rich end of OK.  Too bad I can't get a 52 idle jet .  Other notable things for future tuning is that the richer 55 idle jet crawls a little better.

So your correct jetting may be different numbers but a slightly richer idle will get you a little more torque right at idle for rock crawling based on this experience.

I had swapped the 55 idle jet to the secondary main position just because I didn't have another 50 jet.  I will work on that side later.  Really not sure what the secondary idle jet does since the secondary is closed up at idle except maybe patch the transition when you just barely get into the secondary.

After running that 50 idle jet long enough to establish it was pretty good. I went ahead and leaned the primary main jet one step, from a 140 to a 135.  Running it down the road felt leaner, but not bad.  Today I did a shut down and roll to the curb on the primary circuit at 3K rpms and the plugs read on the lean end of good, confirming my seat of the pants notion, with a little reddish tan tint on the insulator, brown/tan on the electrode and the heat range looking good on the strap.  Jetting looks dark brown on the ring, typical OK.

[LittleSteve]

Hey did you know that you can get a modification kit for these weber carbs?


Its widely available in America and will improve power and economy throughout the rev range. It will also allow it to climb hills without nonsense.

Its not available through parts stores but through more specialist outlets.
I cant remember the name of the place that i saw them at last but i know the boxes come in various shapes and colours which is slighlty odd.

Look for 5VZ-FE on the tag.










Sorry, after the debacle with old blue i decided that the carb is dead to me....
I have a sneaking suspision that theres crap in the tank but never have had chance to suss it out
Ive fitted a conversion to a type 2 vw bus/bag of bolts at work that was an improvement over the factory.
The lads that trial over here if there still insistant on carbs use SU carbs which have a clever fuel metering system and look like they fell off the USCSS Nostromo.

[H8PVMNT [OP]]

I had a little run on today when I shut it off so I backed the idle speed screw down to about 1 turn in which cured it.

Last commute was still kind of porky on fuel so I swapped the secondary idle jet, which we presume you are just into while cruising, down to a 45.  This had no ill effects.  Then I swapped the primary air corrector one step leaner from a 165 to a 170.  This got me a really nice feel cruising down the road, exhaust sounds crisper, and I got 15.5 miles per gallon.  At 15.5 mpg this will save me about $50 a month on my commute. This was varied driving from highway to back road to some stop and go. This is pretty close to my goal of breaking 16 for all around driving.

I am a little leery to dive into the secondary without an AF gauge.  Maybe some small changes and a plug read...

[LittleSteve]

Have you considered a colourtune, it goes in place of a spark plug and is made of pyrex allowing you a window into the chamber and thus the colour of the burn?
 

[H8PVMNT [OP]]

That is kind of cool https://www.amazon.com/Colortune-for-14mm-Spark-Plug/dp/B000E9VGNM