2.5L engine trouble

[MonkUSMC]

So I finally lifted my Jeep up and got the new tires and everything, I drove it around the block, and when I was driving, every few seconds the Jeep studdered almost at an exact time. I pulled into the driveway and it stalled on me and won't start back up, the idle was running very rough also. The engine was rebuilt a few months ago and only has maybe 200miles on it. What could be the problems? I just bought new spark plugs, so that won't be it.

 

Thanks,

LCpl Monk

[Eagle]

What year?

 

How old is the crankshaft position sensor (CPS)?

[MonkUSMC]

It's an 86, and I am not sure on how old the CPS is.

[MonkUSMC]

Found the problem, one of the push rods was completely bent, and the other one wasnt even set in.

[aemsee]

Push rods don't normally just bend on their own. Both push rods with issues from the same cylinder?

[Geonovast]

I'm guessing the exhaust wasn't set in and the intake was bent on the same cylinder.

[Eagle]

You have to wonder how that could happen, since the 2.5L is an AMC engine and there is no adjustment on the lifters. You crank 'em down against a shoulder on the stud.

 

I would do some careful checking before running the motor again, or you could do more serious damage.

[MonkUSMC]

As of now I just need to replace my valve cover gasket, since that it leaking oil. The engine runs fine so far, except the leaks, so I am not using it as my DD at the moment. The rods were on the same cylinder, the one closer to me was off the things, and the one next to that farther away was bent, this was on the 3rd cylinder down looking from the front.

 

Another thing, what was that metal link thing that hooks up to the rear axle for? I know it is some type of brakes, since when the main thing was down, the axle slowed down, I kind of broke it lifting the Jeep up, so I zip-tied it all the way up, lol, it doesn't slow the vehicle down anymore.

[aemsee]

And the prize goes to........Genovast!

[MonkUSMC]

So what would have caused it? lol.

[Eagle]

So what would have caused it? lol.

Very likely, an engine builder who is accustomed to working on Chevrolet engines where you don't crank the valve keeper nuts down tight but have to adjust them. If the builder left them loose on the Jeep engine, they may have been loose enough to let a rod pop out. On the Jeep engine, the bolts that hold down the rocker arms and bridge should be torqued to 19 foot-pounds.

[MonkUSMC]

That makes sense, cause' the bolts weren't that tight on there. The oil was also completely black, and was told that might have caused that too. Thanks for the replies though.

 

LCpl Monk