Outer Limits 4x4 Board

Hey guys I need some help big time i have fitted a Webber to my zook and its way to rich i think anyway my mech sucks and cant help has anyone fitted one or know anything i could do to try and fix it..... also i don't think the mech. did the vac lines properly so its all bad at the moment..... if anyone can help much app.

Thanks

Try three pages down
and look and you will find

http://www.outerlimits4x4.com/phpBB2/vi ... hp?t=28919
start reading

cool never seen a Sierra with a BBQ such a cool idea.

grimbo wrote:cool never seen a Sierra with a BBQ such a cool idea.

wounder if its got a rotisserie on it

As said there is a HUGE thread on here about webers but in a nut shell, small vac hose from dizzy to port on the base of the carb on primary side (side that opens first). Fuel in and out and throttle cable thats about it.
If you have time pull the top and take note of the jets, all 6 idle main and airs 1 for each throat e tubes under the airs and what size aux venturis (things that go across the top of the throats) once you get ALL this info + confirm what type/size of carb (stamped on base plate) come back and we will try to help.
Nik

Dammit Grimbo, you beat me to that one.
I only have a 4-burner Zook i'm afraid.
But i strike a lot of snags. I gave the body a bit of a chop. There was just too much at steak. It needs more beefing up though. I hope it doesn't get t-boned.......

Puk

Checking the current jet sizes helps a lot . Best thing to do is a "plug test" and check the mixture . Drive the engine at a steady cruise at highway speed , no headwinds or hills for a couple of minutes . While holding throttle position shut the engine off and coast off to the side of the road . Allow the engine to cool for around 10 minutes to avoid hurting the valves and pull #1 and #3 spark plugs . Correct color at cruise should be a very light tan/brown . If it's dark or black the main cruise mix is too rich . Completely white is too lean and can hurt the engine over time quickly . Once the main cruise mix is set you can use the same test to set wide open throttle but you have to be very careful . Shutting the engine off above 5500 is dangerous and hard on it , 5500 revs is high enough to check the wide open mix . Again, color should be a decent tan/brown . Use only the stock NGK copper core plugs , nothing else .

Fuel height settings in the float bowl are critical to smooth response and mixture . IF the float is too low it will create a flat spot between the transition circuits controlled by idle jet size and the mains . If the float is too high it will cause huge problems offroad at nearly any angle . If you play with it enough you will find a majic spot between starving the main circuit timing in the primary and flooding offroad . No two carbs are alike since they react differently to the engine they are installed upon .

If you guys need any help, let me know . Email is best or a link to new threads ...

Sarge
Midwest Performance Parts
USA

thanks nik i'll find out what all that is today or tomorrow as it is pissing down with rain up hear and my shed is full of house moving stuff and i have to work out side (tuff break).

Thanks for your help and just wondering if webber made carbys first or bbq's just wondering????

TIK3TS wrote:thanks nik i'll find out what all that is today or tomorrow as it is pissing down with rain up hear and my shed is full of house moving stuff and i have to work out side (tuff break).

Thanks for your help and just wondering if webber made carbys first or bbq's just wondering????

hummmm tough one have to think about that one

Sarge whats the reason behind the plugs you recommend. I have ngk but they are the v groove ones (they were the same price so I thought Id try them)
Nik

Over the years of building crazy engines I've learned nothing out there other than the stock plugs improves performance . The stock fitting NGK and Denso plugs still work the best , especially any of their copper cored versions for use with aftermarket carbs . The U-groove Denso's or V-groove NGK's are fine . The plugs I have issues with are the exotics since they are intended to fire very lean mixes with efi systems . Iridium, platinum and other types are not very well suited to fire the fuel ratio's that a carb will produce . One reason carbs in some cases can produce better power is that have richer ratios during power demands . Efi systems are designed to run basically stoich at all times . 14.7 is a good cruise mix but higher fuel ratios will produce better driveable power when it is needed . The trick is not to abuse that ratio too far , running much below 13:1 is just a waste of fuel , not to mention it can damage the engine over time .

Basically, unless you've radically altered the head chamber design there is no reason to run other than stock plugs .
Sarge

Thanks for clearing that one up for me
Nik

Your welcome.
Has any of you folks spent much time rebuilding or modifying your stock distributors yet ? They are getting old and are known to cause issues when used with an aftermarket mechanical carb that cannot compensate.
Sarge

As yet I havnt but somewhere Ihave info saved on how to reserect an old dizzy, its on my "to do" list which unfortunitaly keeps getting bigger not smaller
Nik

Sarge wrote:Your welcome.
Has any of you folks spent much time rebuilding or modifying your stock distributors yet ? They are getting old and are known to cause issues when used with an aftermarket mechanical carb that cannot compensate.
Sarge

tell us the secret

Knew I had it somewhere
Nik

The stock distributors are getting old and worn . Check the side play in the shaft with the distributor removed, that will tell if it needs to be rebushed and rebuilt . The timng curve can be pretty sluggish if the advance plate is getting sticky, they used a pretty stiff grease from the factory . I just disassemble the plate and clean all the old grease out , then use lightweight lithuim (white) to keep it lubed . The disty isn't very hard to work on , just mark the parts and go through everything . Parts that will need to be cleaned are the advance plate, weight pivots/bushings (some have a nylon liner) , springs and shaft . Don't forget to add some good grease down into the center shaft pivot , it allows the rotor to turn against the bottom shaft section for timing advance . There's a plug inserted in the top just below the rotor that hides a screw that will allow it's removal . The factory service manual does cover some parts of the teardown but not all parts are really shown that well .
Sarge

The biggest trick is to check the shaft side play against factory specs, once it's loose the shaft has to be re-bushed or it will never run correctly. Otherwise, a good lube and cleaning is all most of them need .
Sarge

Sweet dosnt sound to hard so Im moving it up the to do list
Nik

Sarge wrote:Your welcome.
Has any of you folks spent much time rebuilding or modifying your stock distributors yet ? They are getting old and are known to cause issues when used with an aftermarket mechanical carb that cannot compensate.
Sarge

At the moment I'm designing an adjustable microprocessor controlled ignition coil driver, which will interface to the zuki hall effect distributor. Mechanical and vacuum advance mechanisms will be locked on the standard dizzy and just the hall effect sensor will be used to detect TDC. Should be interesting as on the dyno my weber seems to be pretty much spot on with the mixtures across the rev range, but the stock dizzy is letting it down in some areas.

Cheers Dan

Just go and buy the Silicon Chip kit ( not the early one ) does everything you want off the shelf.

Tell me more I havnt heard of this?
Nik

yeh spill the beans im listening

Its a Silicon Chip ( magazine - March 2007 ) kit - what can I say, been around for awhile now. Its programmable, for both load and RPM and for a dissy based installation is probably as powerful as you would ever want. Two maps possible so can have options for high and low octane fuels etc etc.

Probably sold by others but...

Goto Jaycar
use the search for Kits - Automotive

Need CAT. NO. KC5442 ( the unit ), CAT. NO. KC5443 ( coil driver ) and CAT. NO. KC5386 ( the programmer )

and CAT. NO. KC5444 if you want to add knock sensing, although that can be harder to tune for than it sounds

i think i have sorted it out a bit where vac is concerned i have straight vac to the bottom plate and a line to the reg looking thing on the side its running better at idle now just a slight missing on accelerating slowly or at the very start when i put my foot down. how do i sort out the mixture screw and i notice my old mech. didn't put the return line to anything he just blocked it off is this going to cause any problems????

Thanks

The distributor needs vacuum off the "timed port" on the Weber . I don't run pressure regulators on these carbs anymore , just use the second fuel outlet on the carb for a bypass/return into the stock mechanical pump return line . You can just tee it into the return so excess fuel goes back to the tank . This will relieve the excess pressure off the Weber and help a lot offroad . It's real important to use a return line with an electric pump too since they are prone to overheating easily .
Sarge

alright which is the timed port?? sorry i have never worked with carbs or even dissy to be honest as i work mainly on jap imports efi, coils and igniters etc. this is all new for me. the primary jet has got 45 and the sec has got 50 on it is this right??? also i don't think the float has be set up right and with the mixture screw totally in or out it only makes like 500 rpm difference in idle and no difference any where else. thanks for you help so far

TIK3TS wrote:alright which is the timed port?? sorry i have never worked with carbs or even dissy to be honest as i work mainly on jap imports efi, coils and igniters etc. this is all new for me. the primary jet has got 45 and the sec has got 50 on it is this right??? also i don't think the float has be set up right and with the mixture screw totally in or out it only makes like 500 rpm difference in idle and no difference any where else. thanks for you help so far

The timed port is no 1 . But dont hold me to that.

should the vac come off the little elec reg thingy with a valve on top that is stuck to port 1