[Submariner]

How in the hell did I get 5 bent push rods in my 258. pulling head tomrrow to see what is inside cylinders.

suggestions on what might have happered?

just bought this 80 J10 Engine ran well, drove it home, then this happened.

It had sat for 15 years.87K miles on it.

 

[Kruzin]

Bent/stuck valves, broken valve springs, faulty/broken rocker arm pivots, collapsed lifters, extreme over-revving or the engine backfiring are some possible causes for bent pushrods.

 

[jeepdaddy2000]

Don't forget the infamous "3/4 race cam" .

 

[Submariner]

Well the argument now,

Rebuild it? 258

Replace it it with a bigger engine? 304,360

Recomendations

 

[Kruzin]

Bent pushrods don't even come close to being a reason to rebuild or replace the entire engine. At this point, even pulling the head may be overkill if it was just something like a mis-tuned engine was simply back-firing.
Figure out what caused it, you may not need to do anything more than replace the pushrods and tune it up.

 

[Submariner]

I am almost thinking that the timing chain jumped a tooth. that is why I am going to pull the head today. This will give me a good look at how the cylinders are. I also need to replace the rear main seal due to it leaking like a sieve. Then I can look at the exhaut manifold for cracks.

and the list goes on and I can clean up some of the mess in the engine compartment.

 

[whodatschrome]

Jeep sat for 15 years?...bad gas can and will cause bent pushrods. The old fuel will gum up the valve stems, causing the valves to stick inside their guides. Spend the $20 on 5 new pushrods and drain all of the old fuel out of the tank before you fill it back up with brand new fresh gas. Flush the rest of the old fuel from the lines, then start the engine back up.