258 carbed motor runs like crap and dies alot

[Adam]

I have an 87' wrangler and it has the 258 carbed motor. It runs like crap and dies alot. What are some good mods to do to the engine to clean her up and make her feel a little bit better?

[Dukes69]

I made this into a seperate thread for you. You'll probably get more responses.

First off I would give it a tune up: New plugs, wires, dist. cap & rotor. If that doesnt fix it, move to the fuel system: Clean the carb, replace fuel filter, maybe a new pump. Also, check for vaccum leaks, those can cause an engine to run rough. Hope this helps

[TACOJ-7]

I would agree and go FI. carbed motors suck lol.

[rick]

Answer the darn question

Well, if you are looking for info that doesn't involve throwing thousands at the jeep....

Have you done the "Nutter Bypass"? Don't know what it is? This is by far the best thing I have done to my CJ in terms of making the carb perform better. It involves a couple snips and splices of wiring to take the computer out of the loop. If you search on Google for "nutter bypass", you'll get several links (I don't wanna play favorites, so you can look at whichever site tickles your whatever).

Very few people go through the trouble of doing the entire fuel control system diagnostic tests in the factory manual, but if you do, you will likely find that your computer is either bad, or one of the vacuum switches on the firewall is dead (these can be had for a measly $85 at the dealer). So, if you don't have a factory manual or you don't want to go through all the trouble of doing the diagnostic tests (there are about 20 pages worth) only to find out you need a bunch of expensive dealer parts, then just take the computer out of the loop and tune it so it runs well. All of this is AFTER you have done the basics, as mentioned above, particularly making sure your distributor is up to snuff. If the cap and rotor are in need of replacement, you might want to consider doing the GM HEI upgrade (also, google search), or get an MSD ignition setup to boost the spark with the stock distributor (obviously, you will still need new cap and rotor). Also, if the carb body is worn around the throttle shaft, you will never really get it to idle without that little "stumble" that Carters are so famous for. This represents a major vacuum leak, and since they had the foresight in engineering to not include replaceable bushings, you are stuck with what you have, or you can have a carb shop machine it for bushings (about as much $$ as a rebuilt carb).

I don't think you mentioned any desire to switch to fuel injection, did you? If you are willing to shell out approximately $2300 for the basic MOPAR kit, go for it, otherwise, I would suggest people stop torturing this poor guy by telling him he needs to switch to EFI... there are ways to make a Carter perform just fine (for a carburetor). My CJ is proof of that, I had it nose up at the waterfall on Dishpan this weekend, and it didn't stall once. I am also working on the "poor mans" EFI, so be sure to keep an eye on the "Junkyard EFI" thread in this section for future progress. Its going slow, but the parts are coming together to get it on the CJ. I'll be doing a complete writeup on this swap and any and all problems I run into, as well as a cost comparison to the kits out there (HESCO, Clifford, MOPAR). I'm also doing a 4.0L head swap as a part of this conversion. This will not progress much until after the Rubicon run....

Let us know how you do with the tune up, and be sure to post what you decide on the computer bypass, i'd be interested to know if you are doing it.

:shades:

Did this answer the question?...........

[rick]

hmmm

Right here... didn't stall, no problem for the Carter as long as you know how to drive heel toe, with your right foot on the gas a bit while braking....



Man, I really like this pic ....

[Dukes69]

Re: hmmm

Originally posted by rick
Right here... didn't stall, no problem for the Carter as long as you know how to drive heel toe, with your right foot on the gas a bit while braking....



Man, I really like this pic ....

Looks REALLY good Rick. Keep us posted on the EFI swap

[rick]

Yes, but I hope nobody that was there mentions that I slid off the high part of the rock ledge because I was hung up on my belly skid....lol. It does look much meaner than it was though, musta been the great photography !!!

Any luck with the carb Adam? Keep us posted.

[Guest]

Nutter bypass is a great thing to do and Is a valid upgrade , just be careful with the smog laws . Rick I see ADAM is in California too . what are your experiances with smogging after the nutter bypass ?

Also with the BBD carb 90% of the time it is a vaccum problem , I would definately start there . then go to the fuel system , then the ignition sytem . I cannot stress how having pressure/vaccum gauges can help you out in this situation . Very valuable tools to have in your box . We are here when you need us adam !

JIM :{>

[Adam]

Thank you guys for all your help and support!

Well i went ahead and replaced the cap and rotor, i helped a lil bit but not to much. That is all the work i have put into it. It has been sitting in my garage. I have been working on the DD, the tacoma. I'll keep you guys posted.

[Adam]

UPDATE:

I put a new edlebrock carb on it and replaced all the vaccum line to the carb. It runs a hell of a lot better. I working on the timing right now to correct another problem.

[Dukes69]

Gald to hear your getting it worked out. Keep us updated!

[rick]

Right on man! I didn't realize Edelbrock makes a CARB legal carburetor....?

You can probably advance the timing a bit over stock spec since you are not using the computer controlled P.O.S. carb anymore...maybe about 11 or so deg. BTDC. I run 14-15 with an aftermarket cam. You can set the timing with a vacuum gauge if you have one. If not - get one, its a very worthwhile troubleshooting tool. Just advance the timing until you get max vacuum at idle, then back it off to get 1" lower vacuum. You can get the same result by just advancing it a degree at a time until when you short shift it (if you have a manual, shift into 4th or 5th at about 35-40 mph), to kinda lug it a bit and see if it pings. Once you get slight detonation conditions, back it down a degree or so to eliminate the knock.

Good luck man, good to hear its running better.


:shades:

[Adam]

Well, i got all the timgin set and its running really good now. Except i got it going this morning and it died and wouldnt start. I think i got to mess with the choke, i think its stickin. So i have to do a bit of work.
- Change pitman arms
- Replace valve cover gasket
- Fix the choke
- Put revolver shackles on

[Tazdevil]

Hey Rick,

I'm rummimg the 4.0 head on my CJ with the howell feull injection and it works great and also smog leagal

[Guest]

Dont believe A word this Guy ( TazDevil ) says , He is a Jackass!

J/K ......... Tazdevil ( BRIAN ) Is running the 4.0 head and Howell Tbi Setup . It works very well , and the best part is when you open the hood their is no clutter , All the smog B/s Is Gone . As with any thing it takes time to get all the bugs out , but Brian has alot of helpful hints on what it takes to make this system unstoppable .

JIM :{>