Hello Everybody,
Hoping to get a few questions I have figured out. I just rebuilt my '79 F-150's 460, and installed some remanufactured heads I picked up at my local O'Reilly's. Everything was done per the specifications I got out of and the motor appeared to be running fine once I got that big 'ol block back in the truck. It didnt take long however, for me to notice a little knocking coming from the top of the motor. I double checked the timing, since it seemed like it might be off, but after closer inspection and removal of the valve covers I discovered the rocker arms on both the intake and exhaust valves for cylinder 7 had worked their way loose. The rest of them seemed to be fine. One of the lifters had popped out so a push rod fell down and was bent by the camshaft (I'm assuming). The other was fine. I ordered the new push rod (proper length) and re-installed the two that had fallen out. After firing it up again, everything sounded great... until a few seconds later when the misfiring returned, and sure enough, the same push rods fell out.
With that in mind, here are my questions.

1) What could be causing this? Some research online has made me think that the re-manufactured heads may have valve guides that are a little tight since they haven't had much time to break in. Is it possible the camshaft is moving faster then the valves can keep up with due to the friction of the tight guides? If that's the case, is there a way to circumvent this problem until it has time to wear properly? I'd hate to keep throwing new push rods at it until it has time to do so (They might be a $2.50 a piece, but I'm afraid of the damage they're doing once they fall out).

2) Last time I removed the intake manifold (I'll admit, this was a rookie move) the coolant that was in there fell down and into the crankcase, ruining the oil. I did an oil change before firing it up again, and since it hasn't left the driveway I'd hate to ruin it again by flooding it with more coolant when I pull the intake off to fish out the rogue push rod. Is there an easier way to get the coolant out of there? If I drain the coolant out of the radiator, will the upper half of the block drain as well?

Sorry for the rant, but any help I can get would be a miracle at this point, I'm running out of ideas and my head hurts from hitting it on the wall...

~~EDIT~~
Here are some pictures of what I ran into:
You can see the missing push rods on cylinder #7

After replacing the two push rods (Intake push rod is clearly new & shiny) I took a picture

The rocker arms have stamped numbers on them. Can't determine what they mean, even after searching around online and thumbing trhough the various repair manuals I own. The numbers range from 1-4 (3 is seen here) and the tops of the rocker arms seem to have slightly different designs, though when held side by side the base of the rocker arms have the same dimensions... Not sure if this could be causing issues?

 

The pushrod is held in position by the lifter and the rocker arm. I'm thinking it has a bad lifter or rocker studs/arms that are not installed correctly.

You stated that it sounded fine at its initial run. That leads me to believe that the cam lobe isn't wiped out.

Are the rocker arm studs even across the head? Place a straight edge on them and take a look. Any broken valve springs or springs that are too soft and allow the rocker to overshoot and allow the push rod to escape?

Oh... I'll shoot you the ubiquitous "Welcome to FTE"...

 

I agree HIO Silver has a good point weak or broken valve springs could make your pushrods come out and bend .I would also check the 2 rocker arm bolts or studs real close for bad threads.Also on your valve springs the exhaust and intake the same length ?On the 351 w they are different lengths and the exhaust valve has a rotator on top .You did not say what year this 460 engine was newer ones used a pedestal rocker and the old 429s and 460 used a rocker arm on a stud with a locknut

 

Yeah that does sound like a headache. From your description I would guess that it is the valve guides that are the cause of the problem. I might try one more time and if it did it again I would send the head in to get checked or if there is a warranty I might just get a different head. About the coolant, if you drain the radiator it will reduce coolant in the block but some coolant may still be trapped up top so be careful. I hope things go better for you soon.

 

You could check the guides in the offending cylinder by pulling the valve springs and check the valves for up, down, side to side binding. A broke spring would then be obvious.

Since you said the rockers were loose, I would suspect the rocker bolts/studs/ pedestals might be stripped to some degree and not holding the torque.

While you're in there, I would pull those two lifters and check their respective heels for concavity. I know you know not to mix them up but I had to say it.

Good luck!

 

This made me remember when a friend of mine bought a set of reman heads and the same thing happened. Finally he took them back off and brought them to me. I took them apart and here they bored the guides out and never put the new guide liners in...and then someone assembled them that way.
Like already said, check for wiped out cam lobes first. Then I'd take all the springs off and check the condition of the guides and springs. Being that they are remans anything is possible. When you put the new heads on did you check push rod length and lifter preload ? You can't just bolt them on and expect the stock length to work. You have no idea how much has been milled, or how far the valves have been sunk. One more thing to check is the valve tip heights. They all have to be the same. Otherwise you will have tight and loose rockers leading to either bent push rods or leaking cylinders.

 

Did you put new nuts on the heads/rocker arms? Something is not right if it comes loose that quick...Could be something on the head itself not replaced.

 

The heads didn't come with rocker arms or nuts or anything like that, just the valves and springs. I re-used the old rocker arms and nuts, but they seem to tighten up just fine. Once it runs they seem to work loose. Could it be that the push rod comes free and since the rocker arms aren't holding anything down they just rattle loose? Should I try some Loctite?

 

The valve springs are new, they were replaced when the heads were rebuilt, and the threads appear fine. Also, the push rods are the same length for intake and exhaust on my 460 (1979 Model, Vin J)

 

I don't know if it's my old eyeballs, but it looks like you have different rockers on #7 exh/int and on #8 exh than the rest. Sitting at different heights on the pedestal perhaps?

It also looks like #7 exh retainer is scored in a circular fashion - from the rocker hitting it. Not good. I don't see any rotators but some of those retainers don't look right...then again, I can't see too well from the pictures.

Have you checked the clearances between rockers and retainers?

Have you pulled those two lifters and checked their respective feet for staying concave? That would tell the cam condition.....

 

I noticed that too on #7 and 8, and thats what prompted me to check the numbers stamped on the rocker arms, still not sure why they look a little different. As far as the clearances go, they all seem ok. The lifters were both fine as well...

 

The numbers are probably just the number of the tooling that they were stamped in.

I have moved this the the 385 series engine forum. This will hopefully bring new sets of eyes to have a look that may have seen this before since this is an engine specific problem.
You may want to start it with that valve cover off to see what is happening (it will make a bit of a mess from the oil coming off of the rockers)
Best of luck to you.

 

on these style of heads, the valve lash is adjusted by varying the length of the pushrods. the rocker arms are bolted down to i think 25 ft/lbs of torque so there is no adjustment with the rocker arms.

most of the time on rebuilt heads, they will mill the surface of the heads to get them straight ( at least good rebuilders do) this will cause the pushrods to be either too long or too short in some cases. also the rocker arms tips wear causing length issues also.

basically when putting these heads togather, you have to check the length of the pushrods and order the correct lengths in a lot of cases. if the pushrods are too long, they will compress the liter and when you start it up, the lifter will then keep the valve open causing a misfire. if the pushod is too short it usually falls out.

there are a few articles on the web as to how to accomplish this or if need be i could give a quick tutorial on it.

rgds
Mike

 

Exactly right on the pushrod length. If they milled the heads, the rocker gets closer to the lifter, shortening the pushrod. If the old valves were ground, and the seats ground, the valve stem gets taller, simulating a longer pushrod with non adjustable lifters. All fundamentals to consider. The right pushrod length and the specd pushrod length are not always the same.

The factory ford book says to install everything and actually compress the lifter with a pry bar and measure how much room you have between the top of the valve stem and the tip of the rocker arm, I may have to check this but I remember it being in the .250" range, or 1/4 inch give or take, but you can try this with #1 on compression and see what you have. If it is barely any or a lot, you know you have a problem.

I have had best luck doing this with engine hot, but you can rotate it slow by hand and let the valve spring compress the lifters, making it slightly easier. Remember, fors was notorious for sending engines with "stock" length pushrods that were longer or shorter than stock. I recently tore down a 460 that looked to me to be a factory unit with 0.060" longer pushrods. Good luck.

 

hi,im Marco i have a 1987 malibu cobra motorhome with ford 460 efe and c6. Just today im fighting with the same problem,same clynder (7),same valve,the lifter jump out and the push rod fell into the camshaft ,so how you fix this?