Sticky #2 Intake Valve and punctured rocker arm

Welcome to the club.

That looks like a recent very clean rebuild? Were the heads actually done? Is that single valve stuck tight in it's guide?

If the valve is truly "stuck", I'd venture that the valve-to-guide clearance was a bit tight! I don't think this one is due to inadequate oiling through the rocker shaft.
 
Yep it is stuck. Guess the manley push rods are no longer the week link when a valve sticks. :eek6:

they are stout enough to poke rite through the rocker arm.

On a side note find out what the seat pressures are on your setup. More than 90# is a total waste. If they higher, remove a shim as required to acheive a better installed height. Look like dual springs. Don't know what the rates are.
 
Gonna pull the head off this week and take a look.
I was told the spring pressures are slightly higher than stock but not much. I believe the springs came from schneider w/the cam & lifters.
More to come later in the week....
Thanks guys!
 
One other important note to make is, that the red residue you see on the stuck valve is called fretting and or fretting corrosion and it can indicate lack of oil.
 
So pulled both heads off and removed the valves. The stuck intake valve on #2 had the hard chrome "balled" up a bit on the shaft. I had to use my press to get it out of the guide.
The driver's side head was pulled off just in case. The #1 valves (both) had significant wear. They "wiggled" pretty good in the guides. Much more than the 0.002" clearance that I was told should be there.
Buying all new valves and checking the guides. It has a fresh valve job (12 years and 1500 miles ago) so hopefully most of the seats are ok.
I'm going to replace the rocker arm w/a stock one I replaced last summer when I bought a new set w/shaft and spacer springs (5-stand). When I had a tick I started to throw $ at it.....
Will keep you posted as to what exactly was replaced and if it still ticks....:ciappa:
 
Any time any valve guide is replaced or has an insert installed, the affected valve seat must be re-cut to center the entire assembly.

Using the service manual specs, you can see that intake and exhaust valve-to-guide dimensions are different. The actual valve stem diameters are slightly different also.

These are not chryfordrolet motors that all the machinists think about all the time, the ihc motors are different in many specifications and practices.
 
Hey jayson,
it started w/a ticking noise. I assume that was the rocker arm making contact w/the valve. Almost as if there was valve float.
But right after it happened the truck wouldn't idle and had no low end power. The stuck valve is an intake so I don't know what would've happened if it was an exhaust valve.
You definitely know something is wrong when it happens!

Michael, they are going to put in all new guides instead of doing 3 and they will re-do the seats.

Hopefully I will get the heads back tomorrow and re-install next week sometime.
 
77ssii said:
hey jayson,
it started w/a ticking noise. I assume that was the rocker arm making contact w/the valve. Almost as if there was valve float.
But right after it happened the truck wouldn't idle and had no low end power. The stuck valve is an intake so I don't know what would've happened if it was an exhaust valve.
You definitely know something is wrong when it happens!

Michael, they are going to put in all new guides instead of doing 3 and they will re-do the seats.

Hopefully I will get the heads back tomorrow and re-install next week sometime.
Click to expand...

Excellent! That is the proper way to recondition the heads!

When a valve sticks, the engine simply can't make power on that cylinder. If it's an intake valve, then compression can't develop. If it's an exhaust valve, then the same thing (lack of compression) happens only slightly "later" in the scheme of things. Valve train noise will occur at either point since the individual valve operating theory is now screwed and the clearances become enormous.

To actually have a pushrod driven through the rocker indicates to me the valve started seizing (loss of power) and then stuck hard so that the pushrod could either bend or break, or...drive through the rocker. A boat rocker is inherently much weaker due to it's design as compared to a welded rocker arm, thus it's much easier for the pushrod to embed itself. Had this been a welded rocker, the pushrod would have broken. Either way, the valve is tightly stuck in it's guide and won't release after the engine cools down.
 
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