Loose rocker arm

[Coastaldigger]

Hey there I have a 1990 7.3 in a E350 4x4, low milage engine under 100k. Sat for 6 years, started up and it huffs ,thumps or chugs, out of intake. Opened up valve cover and found one rocker arm flopping around with bolt loose , maybe it vibrated back out . No other problems in there it seems, so my question is do I just retorque and move on or is there a reason it's loose that i may be overlooking? Hoping it's as easy as tighten it up and move on! Also thanks for the wealth of knowledge on this site it has saved me a lot of misery!

 

[Thewespaul]

Torque it down and it should be tight, if it’s still loose then the lifter has collapsed

 

[hce]

Check the rest of the rocker bolts. If they are all loose I would replace the bolts. There cheap and it is not a lot of fun to extract the bolts if they break. I went a little overboard and used arp studs, mainly so I could trust that the fasteners met the claimed specs.

 

[Thewespaul]

I use blue locktite as well, but that won’t do anything unless all the threads are perfectly clean

 

[Coastaldigger]

Sounds good hope it's not lifter, I'll tighten it up and hope for the best, thanks a bunch for the quick reply,excited to get this thing back on the road!

 

[Coastaldigger]

Well it must be collapsed lifter, push rod sits about 3/16 lower than all the rest,and after tightening up the fulcrum bolt it's still flopping. I guess I'll pull intake and I have a spare engine for parts. Or may as well do all new lifters. Well that's no fun...

 

[Thewespaul]

While you have the rockers off check the pivot points and the where it rides on the valve stem for wear, get good mahle lifters too, dont run the engitech lifters, they account for most failures ive seen.

 

[Coastaldigger]

Sounds good , also the bottom of push rod just above the ball end there is a worn notch,maybe it drops in the top of lifter and chafes away? Had to tug on it a bit to get rod out too, not too hard but it felt stuck slightly. Tried to upload a pic but seems like diagnosis is lifter for sure . Oh well . Any tricks on IP removal or is it straight forward? I'll search on here some more , thanks, appreciate your time and input

 

[IDIBRONCO]

It should be fairly straight forward. Some things are actually easier to do in a van, like getting to some of the rear injector lines. I've never removed one in a van, but I think that I'd remove the intake first. Then the pump and injector lines should just slide out over the back of the engine (I think). I'd also recommend marking both the pump and the housing together by a light chisel mark, a scratch, or something similar. That way, you can put your pump timing right back to where it was before. Also, don't do this the "easy way" by removing the four bolts that hold the housing down. Remove the pump from the housing by removing the three nuts on the pump and the three 12 point 5/16" head bolts behind the cover on the front of the housing. If you remove the housing, then you have to make sure that the injector pump gear and the cam gear are back in time. It's far easier, to me, to just levae the housing and knowing that the two gears are still in time.

 

[Coastaldigger]

Sounds like I did it right then,got down to the bad lifter,the cup that holds the pushrod has spun sideways. Everything else seems good. Tempting to just swap a lifter in and go but should just order up a set tnite. Would a stuck valve have caused lifter failure? Just problem solving ,I can see if that valve moves later I suppose. Maybe I can put it back together,van is cramped ,but not horrible. Thanks for the talk thru

 

[IDIBRONCO]

Thanks for the talk thru

You're welcome. I always try to assume that a new person doesn't have a lot of knowledge about these engines and try to write plainly (simply) to explain things so that he/she can understand.

Tempting to just swap a lifter in and go but should just order up a set tnite. Would a stuck valve have caused lifter failure?

First, I'd say that a stuck valve most likely wouldn't cause lifter failure. The pistons come up above the deck of the block (the area that the heads bolt onto) So a valve that's stuck open would be hit by the piston with an audible knocking noise. If it was stuck closed, maybe, but it would have a bad miss on that cylinder and probably wouldn't be run long enough to damage a lifter like this. I'd guess that it's from age. The lifter has a spring inside that holds the cup (where the push rod sits) up at the top of the lifter. This spring is assisted somewhat by oil pressure inside the lifter. One of these, by itself won't hold the cup up for long. The springs lose tension over time and don't have enough strength to hold up the cup without a lot of oil pressure. The oil pressure drops dramaticly as the engine warms up. Of course, there's less oil pressure at an idle too. When the lifter raises up to push the push rod to compress the valve spring, it needs all of the pressure it can get in order to compress the valve spring. Without enough internal pressure, the cup can be pushed down into the lifter, which is probably what happened to yours. My opinion is that if one is like this, then it may not be too long before another does the same thing. So you'd definitely be better off ordering a whole set. I apologize for the mini novel, but I tried fully to explain how this works.

 

[IDIBRONCO]

Another thing to consider is the condition of the push rods. You may want to order another set of those too. I bought Sealed Power brand for both my lifters and push rods when I did mine last year.