Fox Rockers coming loose

[J576]

So I've just dropped a 91 f150 302 in my fox, and I keep having issues with the vavle train come loose. I pulled the push rods out and inspected when the motor was out and they went back in exactly how they came out. I've now adjusted them twice and have come loose both times after running for 5 mins. Stock motor nothing been changed.

What the hell am I doing wrong I'm getting annoyed please help

 

[RangerJoe]

If putting back exactly as they were with no other changes, such as different push rods, lifters, cam, head gaskets, etc., then you should tighten each rocker arm while the cam is on the base circle, meaning valve fully closed. This will mean that the engine needs to be rotated several times to get each valve closed. They should be tightened to 20 ft lbs.

Joe

 

[General karthief]

I may be wrong (imagine that) but I feel there is something missing. If you look at one of these videos you will see that there is a u shaped piece that goes between the rocker assembly and the head. I am not seeing this in your pic.

 

[J576]

I may be wrong (imagine that) but I feel there is something missing. If you look at one of these videos you will see that there is a u shaped piece that goes between the rocker assembly and the head. I am not seeing this in your pic.

I don't think there's anything missing, its exactly how I got it out of a running truck, and it matches the motor I pulled

 

[a91what]

@General karthief is talking about the u shaped tray that the two rocker assembly's bolt through, this tray keeps the rockers aligned with the valve.
You may not be showing it in the pic but I can see the tray under the set of rockers adjacent to the ones you have pulled. This tray must be used.

 

[J576]

I may be wrong (imagine that) but I feel there is something missing. If you look at one of these videos you will see that there is a u shaped piece that goes between the rocker assembly and the head. I am not seeing this in your pic.

I know what you meant by the "u" thing haha its there just not in the photos it connects the bottom of the rockers ! And it was installed

 

[General karthief]

Damn! That's twice this week

 

[CarMichael Angelo]

I'm just gonna go out on a limb and say cam failure. If the same two rockers are torqued down and the bolt backs off, that's one thing. But if they aren't loosening, and the pushrod is all kinds of loose after running....I'll take dead cam for 1000 alex.

 

[RangerJoe]

Mike makes a good point. Are the bolts physically backing out, or are the rockers loose?

Joe

 

[darkfader]

Not sure about your rockers but the oil puddled in the rocker in the first pic looks a little off.

 

[J576]

Mike makes a good point. Are the bolts physically backing out, or are the rockers loose?

Joe

The bolts are physically backing out

 

[96pushrod]

Not sure about your rockers but the oil puddled in the rocker in the first pic looks a little off.

Looks like Yoohoo!

Never seen the pedestal bolts back out before. Had them break...

 

[Wayne Waldrep]

Sorry I don't have an answer but those are great pictures. If everyone with a question posted that quality of pic it would be nice!

 

[RangerJoe]

The bolts are physically backing out

I don't believe a bad cam would cause them to back out. Did you use the procedure I listed to tighten them?

If you do it with the valve open, the valve springs and the spring in the lifter will absorb some of the torque load and give you a false reading.



Joe

 

[J576]

I don't believe a bad cam would cause them to back out. Did you use the procedure I listed to tighten them?

If you do it with the valve open, the valve springs and the spring in the lifter will absorb some of the torque load and give you a false reading.



Joe

I did it how you told me too last night, started tdc of cylinder 1 on compression stroke and tightened to 20ft pounds, and then just followed my firing order around, double checked through the order once more and then ran the car for 10 mins. Seems to run really good (besides doing the timing) cable train stayed quiet the whole time

 

[J576]

Might be premature cause I'd like to run the car a little longer but I just want to thank everyone for the help, I really appreciate it ! Now on to the next issue. Coolant looks like its coming from the timing chain cover

 

[Wayne Waldrep]

Might be premature cause I'd like to run the car a little longer but I just want to thank everyone for the help, I really appreciate it ! Now on to the next issue. Coolant looks like its coming from the timing chain cover

Oh no. That's best taken care of before the engine goes in. Much easier to drop the pan, install the timing cover with new gaskets, then the one piece oil pan gasket and pan. I did mine in the car last year. It sucked. If you get to that point there's help to be had.

 

[J576]

Oh no. That's best taken care of before the engine goes in. Much easier to drop the pan, install the timing cover with new gaskets, then the one piece oil pan gasket and pan. I did mine in the car last year. It sucked. If you get to that point there's help to be had.

Haha I didn't know the seal was bad before I put it in the car ! Pretty bummed out on it