OK I have a 88 f-150 with 4.9 big block six and it is my first car and I thought I was hearing an exaust leak right in the number 1 and 2 cylinder area so I pulled the whole top off the motor apart cause I figured I would replace the vavle cover gasket and when I looked inside the number 1 cylinder intake push rod is bent and the rocker arm moves alot. So kinda two questions. 1 is the rocker arm just that loose because no contact with the push rod. And question 2. Whats the possibility old gas and it sat for three years before it was given to me caused the rod to bend.

 

Hello and welcome to the forums.

Sorry to hear about your engine troubles.

Yes, the push rods are the only thing that put tension on the rocker arms, so without them, the rocker arms will freely flop around.

Bent push rods can be caused by a number of things, but yes, sitting for a while can cause it. Dried/caked oil, varnished gas, etc. can cause things to stick and damage things. If the lifters get stuck in their bores, or the pistons inside the lifters stick, the push rod can become bent.

If it were me and you have it apart, take the push rod cover off of the driver's side of the engine and pull all the lifters out. When you do, be sure that you keep very specific track of which lifter goes in which bore. If you lose track, you need to throw them all away and get new lifters and properly break them all in again. Each lifter is broken in and matched specifically to the cam lobe it sits on, so do not mix them up. Also, keep the push rods matched just in case they're different lengths. Usually not, but you don't know what's been done with the engine.

Once you have the lifters out, clean any junk/gunk off of them and be sure they can slide up and down in their bores smoothly. Also, be sure the piston inside each lifter moves up and down freely. If necessary, you can disassemble them with a pair of needle nose pliers to clean up each lifter. I have step by step pictures should you choose to do that.


Once you have it all back together, do a full oil change and put some Marvel's Mystery Oil in it, or something similar, to help clean up the engine. Another alternative is to swap out one quart of oil for a quart of automatic transmission fluid. After a week or two, do another oil change or else all the gunk and junk that's been cleaned out and broken up can start plugging up your system again.

That should help clean it up.

 

Do I need a special to to pull the lifters cause I have a magnetic light with a strong magnet on the end that's flexible.

 

If they're gummy then you won't be able to get them out with a magnet. I've seen them so varnished up I had to hammer them out from the underside.

 

OK and also is there a gasket for the push rod cover on the side of the motor

 

Yes, there is a gasket for the pushrod cover.

 

Well then

 

Thank you all for the suggestions the lifter cam out perfect no effort in a good way no play no scaring cam looked good to from lifter hole no scracthing or scarring. Think it was just old fuel that was really sticky and nasty im going to try to put very small amount of oil on that vavle or maybe even all of them to help loosen them up if they haven't already been loosend up from occasionally running it was able to move the vavle by hand just barely so it cant be to stuck I think I'll get a push rod and turn everything over by hand before I put it all back together. Thank you all for your help.

 

The good news is, your engine looks clean inside.

When I had really gummed up lifters, it was pretty nasty behind the cover and it took hours to get all the lifters out.


On another note, Fram filters aren't recommended. The consensus is usually that the drain-back valve in them isn't very good, so your engine will be dry on startup which wears it out faster. A good Motorcraft filter should do the trick.

I'd still run some cleaner through the engine on your next oil change.

 

Along with phenolic timing gears and cast pistons with steel expansion struts, 5/16 pushrods are another weak point in these engines. I usually upgrade to 3/8 when building one up for more serious use.

 

Hi,Frenchtown Flyer
Like your posts!
Do 3/8 push rods need to be special ordered ? Can you use standard lifters ?
Ty

 

Yes, they are special order. You can order them from Trend. I have the capability to make my own so getting the right length is not a big deal. They have 5/16 ends so standard lifters can be used.

https://www.google.com/url?sa=t&rct=...19408272,d.eWE

 

Pre-EFI heads would need to have the pushrod guide slots re-machined for 3/8" pushrods. No worries with a bolt-down rocker head since it has large cast holes for the pushrods.

 

It would be nice if someone would make a broach to do this job. Its time consuming.

 

Thanks for the link FTF, I was curious about that as well.