sticking vave/tappet when cold

L4-134
At first start-up idling when cold, valve/tappet is sticking.
Runs on 3 cylinders for about 2-3 minutes.
Sounds like popcorn machine, rough, backfiring, etc.
Suddenly clears up and engine from then on runs fine.
Does not stick when warm, only on initial cold start up.
Engine had been sitting for about 10+ years prior to recent startups.
First three startups, had no issues. Ran fine.
It's only the last 3 startups that the problem has arisen.
Add an oil additive, fuel additive, or both?
Take it out and drive it ? (splash oil all around)
Fuel and engine oil all fresh, recently replaced.
Thoughts?

 

take off the valve cover and watch the valves rotate. Make sure they work right. Set lash with feeler gauge. Maybe your valve is sticking. Maybe you have a broken valve spring?

 

Wasn't somebody else here having the same problem in the last few days?

 

I've run the engine at about 2500-3000 rpm over 20 minutes....
It comes right up to temperature.
I would think that would be enough oil "splash" to move some oil around.
Valve/tappet sticks again 2 days later on initial startup.
Think I'll dump some MMO in oil and gas and see what happens.
It's got to be a varnish build up on the valve stem or tappet body.
The Jeep is CA license non-op so taking out on the road to drive isn't a good choice right now.

 

maybe I ought to over fill the crankcase on purpose.....

 

that's an idea
hmm..
with my luck the side cover wouldn't hold it.

 

Drain a quart of oil out, add a quart of ATF, marvel mystery oil, diesel fuel, or the like. Run for the equivalent of 20-50 miles so is fully warmed up and circulated then drain and fill with fresh engine oil and new filter. Check results. This commonly helps in these types of situations.

 

I can understand the ATF since it's loaded with detergent. MMO I don't know. But diesel fuel? Are there additives in fuel that will dissolve the offending gunk?

 

waste of good candy right there....

It was doing the same thing just now.
I just added a quart of Marvel and ran it for 20 minutes.
Tomorrow when I have more time I'll go for a sneak drive thru the hood and report back.

 

Yes. At least the older diesel fuel. Not so much sure on the places with ulsd. MMO, Seafoam, and ATF might be a better choice.

 

Neighbor, way back when, did what Nick said using a quart + of kerosene. Cleaned that 258 right out from what we could tell. He had similar valve train noises/issues on the '75(?) cj5 he had just bought. Changed the oil and filter and ran it for a spell but, to no avail. Drained out a good quart...quart and a half of that new oil and topped 'er off with kerosene. Started the JeeP, warmed it up, revved it up, held a high idle for a while, revved it, etc. etc.. Drained that oil and it was black as hat and nasty. Left the drain plug out over night. New oil and filter and she ran great.......well.......a lot better. He changed the oil and filter again a couple days later.

I'd give it whirl.

 

let me drive it

 

I think you're daughter needs this.
Fallbrook would never be the same.
And no, I'm not letting you drive it; I've seen you drive....

 

I can break it loose jim in just 5 minutes ...let me try ,,,,hold my beer

 

Fired it up once again....stuck again.
So my brother and I took it out and ran it around the neighborhood, shifting thru all the gears, RPMs up high, and blowing the horn at anyone in their front yards.
By the third or fourth time around, most people ran and went inside when they heard us coming...
That's 500lbs of muscle coming at you in a pink Jeep...blowing the beep beep horn.
sorry, no pics....and that's the way I want it.
Yes, our man cards are still intact.