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Old Dec 23, 2010 | 09:45 PM
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From: mukilteo
weber problems please help

so, i bought my truck a couple months back just trying to learn and its gone good till now. it had a weber when i bought it and I'm pretty sure its a 32/36 dgev if that even sounds right but its super rich. it doesn't smoke or anything but it smells like gas and boggs like you couldn't imagine.
i finally decided to mess with the carb not really knowing much but the only way i can get a decent idle from the thing is to bed the idle mixture screw. if i take it out like a quarter turn it drops to like 500 rpm. i have been studying and what i've seen is that it should be out like 1.5 turns and if i put it there it runs like S. I'm totally at a loss. i have been told to re-jet, i don't know how to re-jet. i have been told to change the timing, i don't know how to change the timing. if any one knows how to fix this i would really appreciate the help
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Old Dec 23, 2010 | 10:39 PM
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From: Spokane, WA
dotdotdot..
Maybe it's time you learn how to change timing, and how timing works. As well as, learn what jets are and how they affect your truck.
If you don't, just take it to a shop and have them tune it.
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Old Dec 24, 2010 | 10:42 AM
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From: mukilteo
yeah that wasn't very helpful, I was kinda hoping you would explain some of that but oh well.
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Old Dec 24, 2010 | 10:52 AM
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From: Wilkes-Barre, PA, USA
problem is nick that if you don't know what you are doing or are extremely new to tuning carb's you can do more harm then good to the motor when trying to tune the weber or the factory carb.

Same thing goes with adjusting timing.

These things don't usually go very well if your in over your head.

I can help you as I have the same setup, but I would not want to see you grenade that motor.
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Old Dec 24, 2010 | 05:04 PM
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From: Spokane, WA
Originally Posted by nick-crain-87yota
yeah that wasn't very helpful, I was kinda hoping you would explain some of that but oh well.
Google is your friend, but ill be an internet niceguy and briefly explain some of these things.
timing controls when your sparkplugs fire, relative to crank position. So, 15 degrees after top dead center, means that your spark plugs will ignite the fuel air mixture in your cylinder when the crank is 15 degrees past full stroke. And vice versa for 15 degrees before top dead center.
This is beneficial because it can allow you to tune your engine when your timing chain stretches.

Jets. Go to a motorcycle shop and have them explain jets for a very good explaination.
Essentially, jets shoot fuel into your engine. I don't know how many a 2 barrel cabr has like the 32/36 but I know that there is an idle jet,which is much smaller than the main. The jet sizes indicate the amount of fuel they let through. They're basically a little brass nozzle that gas is pushed through, to combine with air.
The idle jet is generally much smaller, due to the fact that your engione is at idle.
The main jet is ALWAYS larger. Due to the fact that when your engine is running,you'll need more fuel to supplement the engine so that it can runt hroughout the various RPMS. When the engine is too rich,this can be due to a fact tthat the main jets are too large.in which case, you'd have to step them down..

Google the rest
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Old Dec 24, 2010 | 05:53 PM
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From: mukilteo
hey sorry if i sounded angry that wasnt my intention but thank you for the help, ive googled for days i just cant figure out how to change the jets or where they are located but i appreciate the help and im sorry for being snappy
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Old Dec 24, 2010 | 09:23 PM
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From: Spokane, WA
Well, have you checked out the weber website?
The jets should be right by the floats (or they are in a mikuni dirtbike carb)

You'll have to pull the carb to change the jets.
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Old Dec 26, 2010 | 12:12 PM
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From: mukilteo
shoot... well i went on redlineweber.com and it wasn't very helpful but i found a guy that says he can help me with it but i didn't think i was gonna have to pull the carb.
so since i kind of have that one figured out, could you just explain how to do your timing?
i have searched and have not found anything. i would really appreciate it.

Last edited by nick-crain-87yota; Dec 26, 2010 at 12:14 PM.
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Old Dec 26, 2010 | 12:49 PM
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From: Wilkes-Barre, PA, USA
um, what are you doing to the carb that you have to pull it? Search and download yourself an FSM. It will tell you what to do for timing.
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Old Dec 26, 2010 | 03:01 PM
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From: mukilteo
well i was going to put new jets in it.... can i do that with out pulling the carb?
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Old Dec 26, 2010 | 03:47 PM
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From: Wilkes-Barre, PA, USA
just start by changing the primary idle jet. That is right on the passenger side of the carb. Should be a large flathead or 10mm socket for it. Most of the time this is the only thing that needs to be changed on a stock motor. But I do not understand why it is running so rich. There is no reason you should have to shut the idle mixture screw to get it to run.

I would just get someone who knows these carbs. Whoever told you you have to take he carb off to change the jets doesn't know these carbs at all. The primary and secondary idle jets are accessible from outside of the carb. the primary and secondary main jets you have to take the carb apart but do not have to take the entire thing off to do it.

you should not have to change the primary and secondary main jets without major mods to that motor. ie big cam, big overbore, header, forced induction etc etc.
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Old Dec 26, 2010 | 10:56 PM
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From: mukilteo
alright thanks man that was really helpful but i do have headers and no cat... do you think that could be causing any of this? like the idle jets i get but sometimes when driving on the highway it smells like gas so do you think i should change the mains too? and could i change out the jets myself? or should i seek help?
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Old Dec 27, 2010 | 12:54 PM
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From: mukilteo
alright so i finally got the weber running pretty good im still gonna have to change jets but its defiantly doing better for now. i pulled the primary idle jet and its a 60... im pretty much at sea level so im thinking thats a little high but im ordering a jet kit today so well see but does 60 seem high to anybody?
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Old Jan 9, 2011 | 06:59 PM
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Well I can't give you a whole lot of answers but I can give you an example of what I did at a much higher altitude. I bought an 82 not too long ago and didn't know squat about webers or carbs. What I did was maybe risky because I took an educated guess on how rich it was running and adjusted from there. The first thing I did though was pick up a rebuild kit for the carb and the pro spiral adapter from LC Engineering. I also picked up a high altitude set of jets along with everything else....and a weber manual for the 32/36. I read that first and did research on google as to the tuning and looked at what others did. This is what I ended up doing and now she runs like a dream.....minus the fact that I need a manual choke adapter for the carb lol

Here's what my jets are set at right now and a look at what they were:
Primary Idle was 60 so I went down a size to 55
Secondary Idle was 50 so I went down to 45
Primary Air Correction was 170 and now it's 200 (probably a little big)
Secondary Air Correction was 180 and now it's 210 (again probably too big)
Primary Main was 140 and now it's 135
Secondary Main was 150 and now it's 145

Upon review of what I set my jets at I could probably go back up to the jets for fuel that they were set at and be just fine with the increased airflow that I adjusted to. My truck (on 30" tires and stock gearing) would not go past 50 mph. After my adjustments I go all the way to 70 but it basically stops there and I can't make her go any faster.
So on to what I've learned after the re-jet and rebuild.
Your jets come in increments of 5 and the way it works with the 32/36 is that the primary is smaller than the secondary thanks to the progressive butterflys. The reason you need the manual is because you need to be able to tell the difference between the two....it's not labeled at all inside the carb. Also a lot of tuning a carb is feel. It's not an exact science as long as you follow a few ground rules. One get a manual, two realize that gas has an optimum ignition at a 14:1 ratio, and three be very careful when working with the jets and don't crank on ANYTHING. Just seat it firmly but excessive force will ruin the threading....and your carb. Last but not least...unless you know how to adjust the float don't touch it! I do not....and I did not touch the float. I am still doing research on it to see if I can tune out the carb and adjust it for better performance. If your gut tells you that you need to re-jet...you're probably right. I printed these links off when I was tuning the idle speed and air/fuel mixture screws to assist and see if I had jetted correctly. http://www.redlineweber.com/html/Tec...lean_best_.htm
http://www.webercarbsdirect.com/v/vs...ng%20Guide.pdf
That combined with the manual gave me the info so that I could rebuild and rejet the carb. Now I haven't messed with the timing in my engine either and I couldn't tell you how the fjlsdkj to do it. I have also been told that a 260 or a 263 grind cam will perform very well with a weber and I'm saving to do exactly that. I would lean more towards the rejet being the majority of your problem because a carb can be a finicky thing. Changes in altitude, humidity, temperature, and performance upgrades can all easily affect the carb and cause your engine to run like S as you put it. I hope that this helps some an good luck with it. I am still working towards getting this rig to slam out the speedometer...not because I want to go that fast....but that's a good indicator that you're running strong and its tuned well. If you're smelling a lot of gas then you're probably running very rich and you can either shrink your gas jets (which if you go too small you can under power your engine and damage it if you go too far) or enlarge your air jets...but if you lean out the engine too much it will run too hot and like before....damage your engine. My exhaust was running so rich I coulda swore I could light it on fire....it was incomplete combustion to a high degree so I increased my air a lot (since I am at a mile in elevation) and shrank just a tad on my fuel. Now I imagine that with an increase in the fuel on my engine that my cam would probably be the weak point and need to go to the 263 grind so that everything flows nicely. When I started up the truck the first thing that I looked for was my exhaust heating up very quickly as this would be a sign of running to lean. To my surprise I got lucky and guessed right the first time (as far as I can tell) It's been running for about two weeks on these settings and I have zero problems out of it....besides not being able to run over 70mph. Before I go and re-jet it again I am taking it to an emissions testing place on base and seeing how close to the 14:1 ratio I am and adjust from there. Small adjustments are best and while I did not do this (I didn't know what I could do to the engine until afterwards ) please make small adjustments if you do decide to do this on your own. I would hate to see an engine go boom as well. Good luck with yours!

60 doesn't seem high to me though at sea level. I would say with the density of the air at sea level though that you could probably increase your air correction one or two sizes and solve your problem. If someone else has more experience than my one rebuild and jetting please chime in. I wouldn't mind some further advice either.

Last edited by KryptoRoxx; Jan 9, 2011 at 07:06 PM.
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Old Jan 11, 2011 | 07:45 PM
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From: mukilteo
hey thanks man that was alot of good advice. i really appreciate it. Once im not quite as sick im gonna go check for some kind of fuel leak or something cause im really getting worried. Im going to take my truck to a carb shop once im well again but i just feel like im in over my head and every body talking about blowing up my truck is scaring the crap out of me so im gonna leave it to the professionals. thank you for the information it has probably saved me from grenading my engine. lol
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Old Jan 11, 2011 | 08:19 PM
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I priced that out and I think a rejet/rebuild is like 150 so its not too bad...especially for the piece of mind that you can blame someone else lol. Now that I'm done making major adjustments I havent had time to pull the main jets and go one step up.
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Old Jan 12, 2011 | 07:14 PM
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From: mukilteo
yeh that doesnt sound too bad but i dont know if its like a weird obsession but i dont like other people working on my truck. the whole time she was at the shop last time i couldnt stop thinking about her, ha my girlfriend really doesnt like my truck haha
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Old Jan 12, 2011 | 07:52 PM
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From: Twentynine Palms, CA
I don't blame you especially with an older truck. I know right now my family's mechanic back in Kentucky would have a stroke if he saw the current condition of my truck...and see tons of dollar signs lol. I prefer working on my own truck because labor is only getting more expensive these days and it's good relaxation for me.
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Old Jan 13, 2011 | 02:33 PM
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From: mukilteo
yeh i just wish i knew what i was doing so i could do it all myself
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Old Jan 13, 2011 | 04:30 PM
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From: Twentynine Palms, CA
That's why I get manuals for everything before I work on it.even if you know what you are doing they are a great reference to have
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