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My Weber conversion went well and at first all seemed OK. The choke/fast idle and idle set easily and truck performed pretty good. I was still working on my exhaust so final tweaking was expected.

I have a friend that lives on a mountain and the road is quite steep to his house. Truck climbed hill fine but while backing down (idle, no throttle) his drive, it seemed to flood. I suspected "float level adjustment". I searched the forums and "googler" and finally contacted Weber directly.

Fred at Weber sent me the procedure and specs. When I removed the top cover ( small e-clip on choke is a bitch to work with) the measurement from the factory were 30.7mm and 46.7mm. The specs for the plastic float are supposed to be 35mm and 51mm. That is what set it at and reassembled. My drive is not steep at all but does have a slight incline. The truck did the same thing but not as bad as before. It might be just me, but upon driving, it feels like I may have lost a bit of power. I would have assumed that I should have noticed a little more pep.

Anyway, I am seeking advice and info as to what float level specs that most folks have found to work the best. Also are the jets size that come installed the best choice?

I also have a Dist. bearing going and know that my timing is fluctuating a bit, maybe causing some performance issues

Thanks in advance

Bill

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1985 Isuzu Pup 4x4 Longbed, 15" wheels, 1.9L Weber 32/36, Offenhauser Intake (de-smogged), Pacesetter Header (de-smogged), 2.5 Cat Convert, 2.25" Reverse Flow Baffled Muffler and 2.25" Piping

Couple questions

Which Weber are you running?

Where is the distributor vacuum hooked up?

For the 32/36
This shows for a brass float but it does suggest float setting for aggresive 4x setting. So for brass float 50mm max drop standard "For aggressive off-road float drop should be limited to 44 .5 mm max drop"
Just to give you an idea.
http://www.redlineweber.com/html/Tech/3 ... akdown.htm

You probably have this already.
http://www.redlineweber.com/html/Tech/c ... _best_.htm

They also recommend 2.5 pounds of fuel pressure for 4x applications.

Also how much is the idle varying?

I may be wrong on this............I'm running 2 1/2 inch exhaust all the way back off my Pacesetter and my idle does vary a little bit sometimes while idling.

I think 3.5 pounds may be a little high, I'm running 2.5 with no issues on a g200/g180 hybrid.

Your float you can probably set to 35mm and 46mm or 47mm and at 2.5 pounds of pressure your not force feeding the carb.

Unfortunately I can't really say if you need a bigger main idle jet, but the instructions are pretty clear about how to clarify if your running lean or rich by adjusting the idle mixture screw.

Also since your vacuum advance is plugged into the base of the carb, ported vacuum, you can also advance your timing to around 10 or 12 BTC, as long as the valves don't rattle at higher rpm's, it should give your truck a little more pep.

Thanks

I'll follow the tune instructions you posted. I had only followed the install instruction that came with carb

What affect will having the float drop set at 51mm per specs instead of 46mm -47mm? It was set at 46.7mm before I changed it to 51mm. I am still learning

Where should I have the vac advance hooked to? There is another port on the Offy intake just below that I have a line from the valve cover breather running to.

Thanks

Bill

Sounds like your vacuum lines are correct, valve cover to intake, vacuum advance to carb port.

Having the float set higher should keep the fuel in the bowl at a better level while the vehicle may be climbing or descending steeper inclines while the lower pressure keeps from forcing to much fuel into the carb and causing it to flood.

I'm still learning also, the past couple months I've had a warm start issue and have read and re-tuned my Weber just about any way you can imagine. One of the best things I've found is having the vacuum advance hooked to the carb ported vacuum and setting timing to about 10 Degrees but no more than 12.

Hopefully one of the true pro's here can give some insight on what I've suggested

Thank-you Sir

My dist. bearing is starting to go (make noise, slight vibration) at times, at idle, my tach (rpm) jump a bit. I know that I either must replace the bearing or replace the dist before I can fine tune

Before I open up the carb again, I'll work with the fuel pressure then preform then " Best lean Idle Adjustment" procedure by Red-line. The "float level adjustment" is easy enough but the small e-clip on the choke is one PITA. It is sooo small. The first time, I almost had it back on and it popped out of my big fingers and for a while, I lost it. I had a rag covering the carb but I still thought that it had fell in. I found it hiding in a screw slot. There should have been a better design for this small part that must be removed for adjustments.

I am hoping that the big culprit to my problem is the fuel pressure and of course my pending dist. replacement.

Thanks

Bill

There is a mod to help with Webers stalling out on a steep incline, you can do an internet search.
Essentially you plug the stock float bowl vent & install a new vent at a different location. Evidently the stock location allows fuel to drain into the air horn on a steep grade, floods the engine & makes restarting difficult.
Keeping the fuel pressure in the 2.5psi range will help also.

_________________
'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

THANKS SIR

BILL

Thanks Oldestisuzuist

I do appreciate the help.

The one question that I just can't seem to get a consistent answer for is "FLOAT BOWL ADJUSTMENT" Most of the diagrams with numbers, show 35mm and 51mm (plastic float) for closed and open (float drop) At these specs the needle travels 16mm. I have read on several posts, on several forums that the travel should be closer to 2mm.

At 35mm the float is just below level/parallel to carb case face 40mm puts it just about level / parallel. On some writings, it states that the float drop should be limited to 44.7mm (aggressive off-road) which puts the needle valve travel at 9.7mm.

Is the 16mm of needle valve travel needed? Is this to make sure at sustained highway speeds you don't run out of fuel.

Thanks

Bill

Hi, sorry to hijack but I've been playing with my setup a little now that its on the road, am I correct in assuming you mean 10 to 12 btc initial with no advance so you get about 22 to 24 btc with vacuum advance?

Thanks,

Matt

The difference in the drop is that at steep inclines there will be more fuel in the bowl and you won't starve the jets. My weber ran very rich from the factory and no Matter how much i dicked with the idle screw I could not get it right. Mine would backfire and run on. Especially if I was on a hill. I would say you need to go down one or two sizes on the main jets and maybe push the main needle down if possible. They typically send carbs from the factory rich so they can't get blamed for burning up your engine. The best way to tell is from your plugs. Dry and black your rich dark tan and your lean. I would even put some really hot plugs in as these are low compression engines and could use the extra heat for a complete burn. Good luck!

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Fortune favors the well prepared!

Honestly, these engines just don't use the fuel in the carb fast enough so the extra float drop is fine. Unless your driveway is at a 10% incline or more this is not the problem. The first thing I would do is check the plugs for proper burn. Then if you still have the old points style dizzy check those. Once you know for sure your getting good spark then mess with the carb. They typically test these carbs before they go out the door. That's not to say one or two don't slip out a little out of whack but I would bet it's a combination of things.

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Fortune favors the well prepared!