1987 YJ crank but no start - JeepForum.com
 
LinkBack Thread Tools
post #1 of 5 Old 06-07-2013, 10:49 AM Thread Starter
SHUVLHEAD
Registered User
1987 YJ Wrangler 
 
Join Date: Mar 2013
Location: PALM CITY
Posts: 5
1987 YJ crank but no start

Driving down the road, jeep just shut off. Will crank with a weak spark. Not enough to start. Replaced the Coil, still weak spark.
Recently Nuttered, new Cap, Roter, wires and plugs.
Was running perfect since i nuttered it, maybe loading up alittle. Which i think it needs smaller jets in the refurb MC2100 carb i put on it.
Other than that, running great. Checked for loose wires/grounds and nothing.
Any help would be greatly appreciated.

SHUVLHEAD is offline  
Sponsored Links
Advertisement
 
post #2 of 5 Old 06-07-2013, 11:07 AM
Prspallone
Registered User
1982 CJ7 
 
Join Date: Oct 2011
Location: elgin
Posts: 200
This could be many things. It's always a good idea to start by checking the batteries charge though. Could be something wrong with the fuel pump or lines, it's very possibly something with the carburetor though. While you wait for more people to respond take a quick search of old threads with similar issues, you probably will find your answer. Sorry I can't be of more help, but good luck, wacky stuff happens to my jeep all the time. Sometimes the problem takes care of it's self though!
Prspallone is offline  
post #3 of 5 Old 06-07-2013, 11:41 AM
Old4X
Registered User
1990 CJ7 
 
Join Date: Nov 2008
Location: Ga
Posts: 5,145
Time for diagnostics.

Check compression

Check timing, timing mark vs. physical TDC on #1 piston.

Check for erratic timing esp abofe 1500 rpms.

Check vacuum reading, should be 21" MSL, adjust for your height above MSL.

Check vacuum needle at idle, should be steady or all but steady.

Pull spark plugs and "read " them for what is going on in combustion chamber.

Check timing chain for slack. Over 7 degrees, replace chain and both gears.

Check fuel pressure at carb with engine running.

Check for restricted exhaust

Did you add a dedicated ground to the black wire (3 wire harness) from the distributor?


Let us know what you find

418 miles on 19 gallons of gas. Can't beat the BBD !
Old4X is offline  
post #4 of 5 Old 06-07-2013, 11:45 AM
Old4X
Registered User
1990 CJ7 
 
Join Date: Nov 2008
Location: Ga
Posts: 5,145
As you are nuttered, you can wire in a GM ICM in about 5 minutes to check if you have a bad ICM. Just the 2 nutter wires, a hot, a ground, and a wire to the neg post of the coil

418 miles on 19 gallons of gas. Can't beat the BBD !
Old4X is offline  
post #5 of 5 Old 06-27-2013, 10:39 AM Thread Starter
SHUVLHEAD
Registered User
1987 YJ Wrangler 
 
Join Date: Mar 2013
Location: PALM CITY
Posts: 5
Got tired of banging my head and took it MEAN MAX. New HEI ignition and the thing runs like a scalded ape.
SHUVLHEAD is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome