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WEBER 34 DGEC Carb TOO RICH??, Jets & Tune for Jeep 4.2 / 258

99K views 55 replies 16 participants last post by  Fjguercio 
#1 · (Edited)
WEBER 34 DGEC, SOLUTION for Jets & Tune, Jeep 4.2 / 258

Well...... I just got done doing this for the WEBER 34 DGEC. I had a hard time getting help. The carbs do run very rich and yours may use the same jet or close. Please post what Run Jet and Idle Jet you have for primary and secondary onthe Weber 34 DGEC. Write down what you start with for Jets and settings, write down your changes and what you like, what has hesitation in primary or secondary, what is too rich or too lean. This should get you close or very close if things go the same for you as for my 1978 CJ7.

Caution when these things run tooooo.... rich the gas can wash the piston walls of oil and cause an issue. Too.... lean and get too hot and not good. I bet your plugs are black and sooty running very rich.

Here is a write up I did for the Cj Forum. This worked well for me and ALL HWY got 24/25 mpg with MSD ignition. REad on this will help you.....

This is what I have found to work on the WEBER 34 DGEC as far as IDLE & RUN JETS. The Weber 34 seems to run very rich and smoke. I think this will fix the operation for most of us. I have a 1978 CJ7 with Rebuilt 258 Long Block, Borla Header, more modern Jeep water jacket 2 barrel intake---so a very good base line. All pollution stuff removed and only vacuum stuff is Distributor, PCV Valve, Power Brakes. I updated my ignition with the TEAMRUSH & Grounds to Head & DuraSpark Ignition Modual. Still rich but helped. I then upgraded to Summits MSD, multispark ignition and helped a little more. So looks to be the Weber carb is too rich for stock or modified 258 as shipped. I also STRONGLY recommend the Holley Fuel Pressure Regulator set at 3 to 3.5 psi. Without the low pressure fuel the Weber will run rich from my reading & factory. Stock Weber set up not only makes the plugs black but also contaminates the oil with gas and makes it BLACK and lowers the oils protection level. If you have black oil change it.

Order these small group of jets and install them. Run your 258 around town and see if this helps with the smoking. Then pull a plug after 10 miles or so. Then run 10 miles of HWY and pull over and pull a few plugs and take a look. Good running plugs will be tan with small amount of black on the base ring of threads. This jet combo should get you very close.

PLEASE FAX Order to
631-863-2760 WEBER CARBS DIRECT AND INSTALL THEM. THESE SMALLER JETS JUST CAME INTO STOCK. THEN EMAIL ME BACK TO SEE IF THIS WORKS WELL. IF THIS FIXES YOUR CARB OPERATION THEN POST TO WEB HERE, JEEPFORUM , AND OTHERS CAN THEN ORDER THE SMALLER JETS.

The jets for the 34 are not on the web site as of today, they are replacing their phone system so hard to reach them on phone, so the fax is the easiest way to place this small parts order.

WeberCarbsDirect.com
Tech 800-871-3405 and gen # 631-863-2036
FAX 631-863-2760

NOTE: Choke side is Primary side of carb

FACTORY SHIPS WITH STD Jets Run 150/147 Primary/Secondary
FACTORY SHIPS WITH STD Jets Idle 65/47.5 Primary/Secondary
This is what was shipped with my carb. This JET SET UP smoked and plugs were black at idle and run.

ORDER:
New Jets Run 135/140/147 #73840.135 and .140 $5.95 ea
New Jets Idle 40/35/35 # 74404.035 jets Qty 2, one of .040 #74404.040 $6.60 ea

I suggest starting with this set up
Run 140/147 Primary/Secondary
Idle 35/35
And the Holley Fuel Regulator, can order from them also, orders over $49 ship for free.

Runs well 600 to 4000 rpms and pulls the whole way. Normal around town driving plugs look very nice, tan.. The hwy plugs are still tan but little lean. I drilled out the 130 Run jet to equal about a 145 using the 147 using the drill bit shaft as a feeler gauge. Looser than the .140 and almost as large as the 147. BOTH SET UPS WORK VERY VERY WELL. The smaller Idle jets, .035 / 035 will affect the RUN circuit and make it a little leaner. Factory informs the Idle Jets supply about 15% of the fuel when the carb is in the run mode.

Regards,
Fred Guercio

I sell nothing car/jeep related, nor do I have any relationship with Weber. THIS CARB DOES WORK PRETTY WELL AND WOULD LIKE OTHERS TO TRY THIS AND POST UP. ONLY THEN WILL WE KNOW IF WE HAVE A GOOD GENERAL SOLUTION FOR THE 258 JEEP.

Here is a good write up on how to tune the Weber.
http://www.justbrits.com/Articles/TuneWeber.html

Here is another group of write up(s) on how to tune a Weber and adjust the choke on weber.
http://www.izook.com/tech/samurai/engine/weber/weber.htm
http://www.izook.com/tech/samurai/engine/weberworks/weberworks.htm

Here is a good write up on how to read your spark plugs with pics
http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html
 
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#2 · (Edited)
Here is a pic of the Weber 34 with the top plate removed. There are five screws to remove to lift off the top plate. There is also a bolt under the electric choke & support bracket that needs to be removed also. When reinstalling, the choke cam needs to activated to allow the top plate to sit flat. I would hand center the gasket for top plate and hand insert all fasteners before tightening up any of them. Recommend the fastners be bottomed out slowly on reinstall. Snug them up slowly crossing over the carb many times.

The Idel Jets are external on the carb and the brass head bolts can be seen between the bowl for float and venture tubes. There is one on the primary side and one on the secondary side. All Jets are stamped with the size.



Here is another angle of Idle Jet. Just below the top plate mating surface.


The Run Jets are in the bottom of the bowl where the float would be. Here is a closer picture they are at the very bottom. The one on the right /choke side is the primary side for Idle & Run.


I also had a quality control problem that affected my carb operation and the top plate removal and installs. In this pic you can see how the top plate GASKET IS CUT by a 1" x .020" casting flashing ridge along the bowl. In the pics of the bowl above you can see the ridge. This caused a complete carb failure on the Second REinstall and would not run period. I had to replace the gasket and grind down the flashing imperfection. I suggest you remove an flashing imperfection you find also. I am curious if others have different stock jets than mine due to this possible air leak. Looks like all Webers 34 sent with same jets from what I have seen so far, even though Weber tells me these are bench tested and set up for the Jeep 4.2 liter.

To solve the flashing problem I stuffed the bowl with rags, covered with packing tape, and covered the venturies with packing tape and used my dremel tool with fine stone or drum sander and flattened out the ridge till smooth. Blew away any metal filings from work with compressed air. Cleaned out bowl again and wiped and sprayed air. Tried to keep as clean as possible not to plug up the carb fuel passages with debree


The Weber Jets are metric and the Jet Numbers are the metric hole size. I converted them to thousands of inch to compare and use % changes to see how much of a change I made. The jets I selected are much smaller.

When I put in the smaller Idle jets P/S 40/47 vs 35/35 my idle when up from 650 to 1100 rpms with no other changes. THE SMALLER IDLE JETS ALLOWED ME TO BACK OUT THE IDLE SCREW EVEN MORE.... BACKING OUT THE IDLE SCREW CLOSED THE PROGRESSION PORTS AND MADE THE RICH IDLE CONDITION EVEN BETTER. This was the second change of the Factory Stock STD Jets Idle 65/47.5 Primary/Secondary (P/S) that came with the carb in addition to swaping the P/S sides. I like the smaller RUN jets on Primary to get better fuel economy and the secondary to be bigger when you get on it, the gas pedal. Weber seems to ship the larger jets on the primary. I was able to back out the idle screw by 1 to 1.5 turns. My idle screw is now in about 1.25 turns from when it first touches or bottoms out. My manifold vacuum level also went up from 14/15" HG to 18/20" at 650/700 rpm idle with the smaller 35/35 Idle Jets and the idle screw at proper 1.25 turns range.

THE REASON..... WHEN THE WEBER 34 IDLE JETS ARE TOO... BIG.... USERS NEED TO SCREW DOWN THE IDLE SCREW TOO FAR AND EVEN CLIP THE LOCK SPRING TO TIGHTEN DOWN FURTHER TO GET THE ENGINE TO IDLE. WITH THE CORRECT/SMALLER IDLE JETS THE IDLE SCREW WILL ONLY BE TURNED DOWN APPROX 1.25 TURNS AFTER TOUCHING BOTTOM. WITH CORRECT IDLE JET SIZE THE IDLE SCREW SET APPROX 1.25 TURNS, THE THROTTLE PLATES ARE CLOSED, AND MANIFOLD VACUUM LEVEL SHOULD READ 18 TO 20 AT IDLE ON A SOUND ENGINE. OLD engines might be a little less. THE CLOSING OF THE THROTTLE PLATES CLOSES OFF THE PROGRESSION PORTS HELPING THE RICH IDLE PROBLEM EVEN MORE.

Once I got the smaller 35/35 idle jets my run jets were too lean now. The Idle Jets supply 15% approx of the run jet circuit. So kept increasing the Run Jets size till the plugs looked nice tan color. Run Jets 140/147 was just a little lean on the hwy. I drilled out the 130 to EQUAL A 145 and that combo of P/S Run 145/147 and Idle 35/35 that seems to run well for me.

You can also take one of the smaller jets and drill it out with english or metric drill bits to get jet size not offered. I drilled my 130 run jet to 145. This was my final setting used in Run primary jet. You may want to use two 147 / 147 Run Jets.

Please write down and post your stock jets that came installed on your new Weber 34 so we verify the same as mine or different. Also let us know how this set up ran on your 258 or even 232.

Regards,
Fred

Print the reference links in case they get moved or deleted. This is the most info you will find on the Weber 34 DGEC and Jeep I6 in one spot. This should also help you with the other Weber carbs also. AS ONE OF THE TUNE LINKS SAID.... ALL THE WEBERS RUN THE SAME!!

JETS Available:
Run Jets: 150, 147, 140, 135, 130, 125, 120, 115, 110

IDLE Jets: 65, 50, 47.5, 45, 35

Factory says the air correction jets do not normally change.
 
#3 ·
Last note. The yellow staining on the outside of the carb is gas. I think it is from the top plate gasket being cut by the casting flash on bow lip. It could also be the carb was so rich the gas come out the piviot points.

My electric choke, electric manifold heater and water/collant jacketed intake are working perfectly and yours should be also. If you have the older cast iron manifolds make sure your heat riser flap moves freely, is lubricated, and working. This is a flap between the warm exhaust and the cold intake air.

Regards,
Fred
 
#7 ·
My carb came with run jets 135/135 and idle jets 55/55. I put in 35/35 idle jets.

I left the run jets as 135/135 and cannot put in a 147.5 run because i do not have one.

Also can u please label the idle, mixture, etc screws on one of the pictures. its hard to find a good pic, i just want to make sure im adjusting the correct screws in the correct order.
Looks like the Factory is putting in some smaller Jets since I got mine. I think the run jets to small and the idle jets are still too big. Thanks for sharing that information on stock jets.
 
#10 ·
I don't have time to post much now, build crunch time, but only have one real comment on the so called 'weber' 34 clone carb.

In my firm opinion if you bought this clone carb made by a French Moped company, Solex, you just plain got ripped off and you should send it back to get a Real Weber if that is the brand you prefer or any other "Real" carburetor like a Holly remanned Carter BBD or an MC 2100 or.....

Power to you Fred for helping out others who also got that clone, good post.

And don't forget that "any" carb you buy needs a kit put in it every time your engine needs plugs, it is also part of a major tune up according to the Jeep CJ maintenance schedule and always got done at any garage at tune up time I ever worked at.
 
#11 · (Edited)
Dear Mike Romain,

Thanks for your comments, I/we value your opinion, and nice your actually read (possible) some of the Weber Posting Information and Web Links prior to all your negative posts in the past day. Some of your recent comments showed me you never read thru the WEBER POSTING & LINKS. Knowledge and the web is a great thing. This information is true for All THE WEBER CARBS, THEY ALL WORK THE SAME.

Many if not all multinationals companies use subcontractors to manufacture for them. Then we need to throw out many other companies with this bath water. At least they are not made in china, they are all made in Europe, in this case England and France and have been for what 50yrs, used on Porsh, BMW, Audi as oem and aftermarket.

THIS THREAD, has been looked at by nearly 900 JF members at this time. You are the first one to pee on it. You also pee..ed on 4 other threads about Weber Carbs. I ask you to consider removing the above post or at least reword it so you do not scare anyone to the point they believe not and give up on their Weber Carb.

I believe more and more of us will find the Weber 32/36 and 34 will work just fine. As posted in other threads looks like Weber is already shipping the 34 with smaller jets than I am recommending. ONCE I get more proof what is close to correct with VALIDATION of other success can I ask the factory to change to the above set up.

There are several posts saying the weber is working fine, EXCELLENT ACTUALLY. There are LOTS of post where JF folks are saying they need help. I was one of the folks that needed help and gathered as much information as I could and put it in one spot.

I posted this link to the YJ Thread last night, they need help too!!

Our converstions were on other threads and I feel you should have stayed there... those 2-3 threads that are current in the past day. Maybe next year at this time you will have a different opinion.

Keep the faith, it does work, regards,
Fred
 
#12 · (Edited)
Just for a little confidence in WEBER CARBS here are a few recent postings. I hope the guys do not mind I copied over some of their statements in whole. I even added the rotary pump to the write up above several days ago.

Thank you JeepForum,

Fred

PS I add will a short video spring time when all the salt is away and the CJ comes back out. She runs like brand new.

Adjusting a Weber is just as easy if not easier than a BBD and no need to rebuild it once a year. To each his own, but if you can tune a BBD you can make a Weber purr. Putting the proper jet in at the initial set up is key as well as a FPR. Both are clearly stated in the instructions. I wouldnt run any other carbuerator.
Dude my 34 runs great out of the box, and its supposedly a solex with the weber name on it. look on page 1 about the proper fuel pump to use. This is where a lot of peoples problems stem from they just don't know it.
There is always one debate when installing a Weber. Check this page out.....
www.racetep.com/webfuelspark.html#webfuel

It shows how the Carter 4070 rotary electric pump is the one simple answer to this reoccuring question. It is a high volume low pressure rotory pump (constant flow, not a pulse like other crappy elec. pumps or like the stock mechanical pump.) Regulators only decrease the life of a pump. So why not find a pump that operates at your needs? The 4070 pumps at around 4psi but flow around 60-70 gph. Perfect for what any weber needs! It costs around $80- $100 and comes with everything you'll need except a little extra hose and wires. When I found this I was sold, I bought my Weber, did the Nutter bypass and only a little adjustment. Make sure the remainder of your vacuum lines that you use are routed properly and reset your timing on your distributer 14 degrees BTDC @1600 rpm.

Cheers
I have the Weber 32/36 on my Jeep, Came with it.

Bought a jet kit and a FPR for it. Runs sweet.
Currently getting 16 MPG with 2.73's and 33" tires
I have the same setup as you do. Yes, Nutter. The Nutter has nothing to do with the carb directly. I have been in your situation more times than I can count. My bet is your spark plugs are black if you pull them. Clean them, get new ones, whatever, I have done both. Then print off the Weber directions for getting the fuel/air mix right, I can dig them up but just look on redline website for the steps. Follow them exactly. Should be up and running in no time.

If you need help nutter or need advice, check my signature. good references on there.

Not related to your question, but i recently put on an HEI dist. and have not had a problem since. I'm only telling you this because I was you 11months ago with all the same problems.
Honestly, even with a 4.0 head and HEI I am still running super, super rich (I am fully adjusted). Look at this write-up, that is my plan to get this thing going right.
http://www.jeepforum.com/forum/showthread.php?p=5993602

SILVER 87 YJ, 4.2, 4.0 Cylinder Head, HEI, D44, Champion Winch, Weber 34/34, Nuttered, MORE 5/8" Boomerangs,Yellow Top, 1" BL, Custom Front Bumper
John Strenk said:
Fred,
Nice post you got going. And like you said, all Webers work the same.

I had a Suzuki I but a Weber on and even with a Header, Crane Cam and other goodies, I was able to get such low emmision out of it on the dyno used in our state the inspector re-calibrated his machine to make sure it works. I went from having to take it to a emmision specialist to make it pass sometimes with a waiver to no problems at all. I even found that the Weber used on the conversion was almost the same as used on my old Dodge Omni
I have a Weber 34/34 right out of the box with no fuel pressure regulator and mine runs amazing. It doesn't hesitate or studder at all on inclines...
I run a Weber 32/36 on my CJ. I didn't need an electric fuel pump (just my stock Jeep one), but I do use a fuel pressure regulator. The Weber is set up for about 3.5psi and the fuel pump puts out @7psi.

The Weber was easy to install and tune. I haven't had any problems with it at all!

Warren
My all-around favorite would have to be a Holley 2300 for simplicity, downright reliability, and easy tunability. I run the progressive Weber 34/34 on my CJ and it gets much better fuel economy than any other 2bbl, and still has some umph. IMO, the Holley is simpler and easier to tune than the Weber. The Weber 32/36, and Holley 5200 (basically a Weber 32/36 clone manufactured by Holley) are also both great carburetors and are very fuel efficient, being progressive 2bbls.

My CJ sees a lot of on-road driving, so fuel economy is pretty important to me. That's why I run a progressive Weber on there.
The same thing was going on with mine, put the weber 34/34 in and runs perfect. Gas milage isnt to good, but its a jeep, what do you expect, ha.
 
#13 · (Edited)
THE LAST PART OF THE JEEP 4.2/258/I6 ENGINE PUZZLE???

Fjguercio said:
The Information above on the WEBER 34 & 32/36 and links can help with your Jeep. Below are links for TeamRush, a much, much, much, better set of tune up parts bigger cap/rotar with brass terminals and a process for making sure your computer is not messing up the operation of your Jeep. I also have a link to a nice review of how you can use your weber and clean stuff up. Sorry that post got a little out of hand, but still go info. I could take it all over to a new post if you JF folks think it should be.

These are some of the best examples I have seen on the web.. with pics, they are excellent!!!!

TEAMRUSH... better tune up parts cap/rotar for 4.2 Jeeps
http://www.jeepforum.com/forum/showthread.php?t=669495


Jeep COMPUTER make sure it not messing up the engine operation, Nutter and BBD Pin set up is here
http://www.jeepforum.com/forum/showthread.php?t=522262


Simplify the engine with the nonfeedback carbs, including the WEBERs with pics and discusses some of the upgrades. Turned into a bit of a pissing contest but good information.. Some good pics too
http://www.jeepforum.com/forum/showthread.php?t=677648


Fred
 
#14 ·
Fred:

Excellent post and very eloquent. I think you are spot on and wished I had taken time to refute some of the negative posts.

I agree that many companies sub out thier work andt the fact is that it is built to the same specs.

Keep up the good work.
 
#16 · (Edited)
Dear Scottsjeeprolet,

Glad you are getting some help. I still think the idle jets at .045 are too big, and since you said smoke less, sounds like that is true. I have not spoke to Jose about my POST WORK YET.

Be carefull with the AFTER MARKET HEI, make sure you read a few posts about the HEI that JeepHammer has discussed how to test the drive gear to make sure it is not hardened metal, and fits properly in your 258. Failure to do this could take out your engine. So be well read and safe before you install this. www.junkyardgenius.com/ignition/jeep/heicompair.html

I suggest you order the 35 idle jets and one 147 run jet since you already have one installed. If you do not have a 147 run jet installed order 2 of them. Then go thru the process of tune and time adjust.

If you have further questions copy this single post to another THREAD and ask away. Once we get you fixed up can post a short note back here what the final selection was.

After a few more of these maybe Jose with ship out the same selection of jets for the Jeep 4.2.

Regards,
Fred
 
#17 ·
How's it going Weber Guru's!!

I have a buddy with an 86 CJ-7 which he installed a Weber on. He enlisted my help to tune it. His box had a part # of WK551-38 is this carb too big for the 258? I don't hear it mentioned very often, is it different than the 36/36? I really don't know much about the Weber, but have tuned several MC2100 and Carter BBD's. We have installed a FPR and set the pressure at 3psi. I checked all his connections including the charcoal canister and all are correct. It runs very rich, and can't get it to idle below 800rpm. None of the jet #'s mentioned here are in his WEBER Performance Jet Kit, and I haven't read any mention of the Air Correctors in this post. Are they swapped out very often? This has been the most detailed post I have come across on the net. GOOD JOB!!

Any help would be great!!
 
#18 · (Edited)
86 CJ-7, Weber 38
We have installed a FPR and set the pressure at 3psi.
It runs very rich
can't get it to idle below 800rpm.
None of the jet #'s mentioned here are in his WEBER Performance Jet Kit

I haven't read any mention of the Air Correctors in this post. Are they swapped out very often?
81 Eagle,

I would suggest you copy, cut& paste, your post and mine and start another thread. Ask for help on the 38 and I and other can help. This is more of a information location than help post or it will turn into a mess. Use the web adress link on top of page to refer to this POST AS REFERENCE INFORMATION AND START YOUR OWN THREAD.

I would prefer JeepForum Members put what JET CHANGES worked on their JEEP 4.2 / 258 here. MOSTLY for Weber 34/34 and some Weber 32/36. This gives us a good base line and proof so I can talk to Weber and have the correct jets shipped stock.

I am also interested in what Weber is shipping as stock jets Idle and Run on new product. This may alow us to modify what Weber is shipping on the Weber 34.

We can only get this done after some validation from you guys.


YOUR QUESTIONS & ANSWERS:
The Weber 38 are too big for most of the Jeeps unless the engine is highly modified. YOU were silent on your engine mods if any???

Might be able to run jets slightly larger than the 147 Run & 35 Idle jets for the 38. That is a TOTAL GUESS ON MY Part. Please post what jets came stock in the new 38 and what was in the TUNE KIT for 38 IN YOUR NEW POST AND HERE FOR REFERENCE. The Jet PART NUMBERs for 34, 38, 32/36 are not interchangeable. They still use metric drill bit holes so simillar in that way and the metric drill size in in the part number.

The air corrrection are generaly not changed per my conversation with factory. The 38 operates both Venturies at once, the other Webers are progressive and start with Primary and then open the Secondary.

MAYBE?? ask if you could exchange for a smaller weber unless there is strong reason why. Maybe they/seller made a mistake in recommending the 38.

Ball is back in your court. Need to copy/paste to another Thread, and put more about what you are starting with. I would also like to see some PICs from top front, both sides. The vintage Jeep will have a computer to disable at min and there are some Igniton Upgrade to be done like TEAMRUSH, extra grounds, and those things are discussed and linked above.

This has been the most detailed post I have come across on the net. GOOD JOB!!
Thank you, it needed to be done!
 
#19 ·
Thanks for the quick reply.

I believe he got it from QT or 4wd Hardware. The engine is basically stock. All the emission must have been removed because the pulse air tubes, cat, and mess of stuff that normally resides on the valve cover is missing.

I have no idea if the internals have been messed with, but it really doesn't look like it. Everything on the long block looks factory and not disturbed. I will do as requested and take some pics of what I'm working with.

From your response I gather the 38 is a totally different carb than the 34 or 36. What type of application is the 38 suited to?

Thanks for all the help!
 
#21 ·
hi,:wave: I just installed the 34 on my 89 YJ. I ran everything per the instructions but just want to make sure of the vaccuum lines that remain. Will someone PLEASE post some pics of the inside of their engine bay and show me these lines coming from the carb!? I was confused about the pipe coming out of the intake base that said to run it to the valve cover, does this mean the rear breather? Also, it said to drill two holes in the top of the intake and run vaccuum lines to them because it needs filtered air>? what lines are these, are they necessary?? I got it running, starts rough, then a nice idle sets in, around 600 RPM or so. If I power up, say 2k RPM it responds well, but when I hold it at that RPM it sounds like its pulsing. (vrooom rooom rooom room room) haha everyone say that outloud and youll get the idea. I am nuttering it tonight. Could the old ECM be making it do this?? Anyways, any help is much appreciated. Thanks in advance :thumbsup:
 
#23 ·
I have asked several times, If you need HELP then start a new thread with your details. The YJ Wrangler, Twisted125, needs to post in the YJ Forum. Send me a PM with Link, I will look. I NEED YOUR HELP JEEPFORUM, IF YOU DO NOT, I WILL HAVE THE THREAD LOCKED.

IMPORTANT:
I have asked Scottsjeeprolet and others to post what jets were stock and what jets worked out well. That information is the only type of information I want added to this thread.

I am most confident if we used the Jets & Tune information above the JEEP 4.2 will work quite well. IF.... IF.... IF.... we can validate this with 20 Jeep 4.2 /258 or 232's with stock cams so forth..... I will contact Weber and try to MAKE THAT JET MIX STOCK. This way we do not have to work at it so hard. I need your help to do this. We have the Jeeps and need to transfer the results back to Weber. They / Weber does not have 100 CJ's to tune in the garage if you get my drift.

I have many, many, many days of work and research into this project/thread, please read and follow the instructions.

Thank you,
Fred
 
#25 ·
I just installe a Weber 34 on a 87 YJ. FPR set to 2.5lbs and nuttered. Came with 47.5 and 55 idle jets. Runs fine. Great actually. Mixture screw is 2 turns out. Any closer in and it starts to die. I'll check the plugs later this week when I team rush the ignition. I'm at sea level. I know some people had problems with the Weber running rich who were at high elevations.
 
#26 · (Edited)
ok so i got the 34 dgec carb like a week ago and thru trial and error we ran a line into the fuel filter and sprayed starting fluid into it ( it stalls just above 2 grand) and when we gave it a shot of starting fluid it ran like normal any ideas--- im thinking of getting biger jets. it seems like its starving for fuel

oh and im running 150/147 and 55/47.5

main problem is when accelerating about 2grand it completely dies

http://www.jeepforum.com/forum/showthread.php?t=725115&page=3

the thread i started and everything i did to fix the problem and i still have the problem
 
#27 ·
I just called the 800 number listed earlier (800-871-3405) and told the guys the problems I am having with running rich. They are sending me a jet pack free of charge with 35 idles and I believe 135 mains.
 
#28 ·
Hey thats great news.. very nice of them to send you smaller jets. When you change your jets please add what jets shipped stock in your carb in the post above. Primary, secondary, run and Idle.

If you read my thread closely you may need the 147 Main Jets. I think the 135 might be a little too lean, but if you are completely stock might be ok.

Regards,
Fred
 
#30 ·
Dear Scott,

It a Weber 32/36 by the way. I have told you prior post the 45 idle jets are going to be too big. The past posts are copied below. If you do not follow directions please do not post here it is not working. If you need help please start your own thread and put the web link above in your post for reference. I do not want this tread cluttered.

I do not want to LOCK this thread yet because my research and work is not done yet.

I do want information on what jets came stock and what jet selection worked well for the primary, secondary, main jets, idle jets.

I'm still working on my 36/36 i just got. I called Jose and he sent me new idle jets FREE. I put in the .045 and it seems to idle better and less smoke. I just ordered the CRT Performance HEI dist in hopes of helping the jeep run better. i'll let ya know how it works.
Dear Scottsjeeprolet,

I still think the idle jets at .045 are too big, and since you said smoke less, sounds like that is true.

I suggest you order the 35 idle jets and one 147 run jet since you already have one installed. If you do not have a 147 run jet installed order 2 of them. Then go thru the process of tune and time adjust.

If you have further questions copy this single post to another THREAD and ask away. Once we get you fixed up can post a short note back here what the final selection was.
 
#32 ·
Scott,

How about that. I do not think the 36/36 was avail when I was looking to buy a carb. So I have not seen that one prior. Thanks for showing that to me.

The 36/36 refers to the Venturies in Metric so you carb holes are bigger than mine. The jet selection is also metric drill hole sizes. I would estimate since you have 36/36 Ventures your Idel Jets would be the 35 or 40. Same thing with the Run Jets your situation might want a bit more fuel. I would think your Idle at 35 or 40 and the Run Jet at 147.

A Ratio Check on idle jets???
45jet divided by 40jet is 1.13 or 13% more fuel in the 45 vs 40
45jet divided by 35jet is 1.29 or 29% more fuel in the 45 vs 35

Those Jets Should be very close. Keep cking your spark plug condition also. The picture guide LINK is on page one.

If you need to discuss this more prior to the proper jet selection and tune of carb please start another thread. I will see it and help you there.

Regards,
Fred
 
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