87 YJ wont start

[allabs5150]

1053954

Hey all, Well I asking a question for a buddy of mine who's having a bit of a starting problem with his 87 YJ.
Heres the deal...the factory carb was really giving him the business, you all know the deal tough starting & ideling, last sunday he turned it off after driving for a while then couldnt get it to start, after it sat a day it fired up....heheheheh no surprise there!!!!. but after drinving it it did the same thing, and even after it sat he couldnt get it running, so he bought a weber had it professionally installed and now the mechanic is pullin his hair out cause he cant get the %$#@!* running. It turns over has plenty of spark and the carb is pumping fuel the dam thing just wont fire, sometimes it sputters like it wants to start but never does. What do you guys think???[addsig]

 

[CARDOC123]

1054023

I guess my queston would be, does it have compression? This is the reason I ask. The cylinder walls are actually sealed with oil, along with the rings. If the carb dumps too much gas down there it will wash all the oil off and then you don't have any or little compression. I'd have the compression checked just in case. If there is no compression then add about 2 tablespoons of oil into each cylinder turn the engine over a few times and if all else is good it will start. There will be ALOT of smoke but this is ok. If that's not the problem I's suspect timing. even though you have spark and fuel, if you don't have them both at the right time it still won't work. These are the simple items to check. there are other more complicated but that will come later if this don't work. Good luck.[addsig]

 

[CARDOC123]

1054024

Oh yeah, one other thing. If the plugs that are now in the engine have been gas soaked, replace them. Because they may or may not work.[addsig]

 

[jay89]

1054032

Starter or starter solenoid? Maybe loose connection.[addsig]

 

[flyboy]

1054065

sounds to me like an ignition timing promblem have the timing checked... :-D [addsig]

 

[MadMiracle]

1054630

I'm almost sure it has to do with the SSI (solid state ignition system). I was a hair away from converting my carbed YJ to a TBI because I was so sure it was the carb. It took 200 to 300 turns of the key to get it going and what was weird was that it would sometimes only start when the engine was dead cold. Turned out it was the SSI which consists of the MCU (micro-computer unit, ignition control module and distributor pickup coil). I had all those components replaced. Now, it fires up and keeps running on the first turn of the key.

edited by: MadMiracle, Feb 11, 2003 - 06:57 AM[addsig]

 

[jay89]

1054667

Do a nutter bypass to eliminate the ecm. Doesn't cost a thing and it is easy fix. If that works upgrade to a juice box.[addsig]