[PredatoryTrep]

Just like the title says.

Got a fraternity brother with a 1975 AMC 258 with the 4.2L I6.

Problem is, it won't start.

It will turn over, but no ignition of the fuel.

He has tested all of the following:
Fuel Test
Fuel Pressure
Spark
Compression
Timing
Battery Voltage
Ground/Power Cables

He has replaced literally every piece of the ignition system from what he said.
Still, no go.

It ran fine until a couple of months ago, then just wouldnt start one morning. Has never been able to figure out why.

Any ideas from the great minds here?

 

[Daytrepper]

So it has no spark?

 

[PredatoryTrep]

No, it does. Everything he tested was fine.

Thats what doesnt make sense. There aren't any sensors really...

It has compression, spark, fuel, and correct timing. What the **** else does a carb'd engine need??

 

[Daytrepper]

No, it does. Everything he tested was fine.

Thats what doesnt make sense. There aren't any sensors really...

It has compression, spark, fuel, and correct timing. What the **** else does a carb'd engine need??

Well...one of those is missing, otherwise, it would be running.

Only possibility I can think of with everything present is it is flooding, or flooded....too much fuel...choke closed too long, too much pumping the gas, etc....or the points are not set properly...or are bad...if it has breaker points. Either the fuel mix is not correct or the timing is off...

 

[PredatoryTrep]

Heres the thread that they have going on the Jeep forums. Quick page and a half read through.

http://www.jeep-cj.com/forums/f49/75-cj5-wont-start-please-help-13474/
Also heres a picture of their current timing. Slight slack in the chain

 

[Daytrepper]

Heres the thread that they have going on the Jeep forums. Quick page and a half read through.

http://www.jeep-cj.com/forums/f49/75-cj5-wont-start-please-help-13474/
Also heres a picture of their current timing. Slight slack in the chain

Chain looks to be lined up fine....The slack really wont throw it that much....but might as well replace the chain and gears if your torn down to that point....First and foremost follow the advice of user TeamRush on that forum.......

IMO, over the internet, definitely a timing/spark issue!

 

[DrDodge]

1975,, Id suspect motorola electrics,, , and it should be a ford eec1 ignition, on the left side of the engine compartment should be a brain box,, kinda like a mini computer,, im betting thats the problem

 

[beeblebrox82]

1975,, Id suspect motorola electrics,, , and it should be a ford eec1 ignition, on the left side of the engine compartment should be a brain box,, kinda like a mini computer,, im betting thats the problem

check the grounds?

 

[DrDodge]

check the grounds?

yea,, theres only 1 or 2,, been so long since i worked on one of them, think the last one i goofed with was at the AMC dealer i worked for in Fl........