Hey guys,

Car had been running rough and I pulled a valve cover as I heard rattling, and found one rocker was twisted/crooked and not aligned with the valve tip anymore. Wtf can cause this, and what is the fix?

Thanks!

Ken

 

pushrod guide plates need installed or swap back to self aligning stock rockers meant for 1987-up heads.The pushrod slot on the later heads is too wide to keep rockers aligned properly

 

Remove that rocker and take another pic or two and post them so we can actually see what the issue is, and not the cuase of the issue.

 

Can't see the head well enough to tell what you've got. Looks like the 86-back style slotted push rod holes and perimeter-bolt valve covers but can't be sure. As said, pull off the rocker and take a pic of what's underneath it.

If it's that type the push rod is bent and/or broken.

 

I concur. Looks like he needs guide plates or self aligning rockers. But a better picture of the rocker would help. Remove the rocker. Flip it over and take a picture.

Fred

 

Thanks for your input so far guys - will pull the rocker tomorrow and take new pics. These are World Products S/R Torquer 305 heads that had been on the car for over 20 years.

 

A pulled rocker arm stud perhaps? Is there vertical play in the rocker arm?...

EDIT: I missed the part about them being after-market heads.

 

Well, he says he has World Products heads (without saying which ones); not stock. So there's a whole different range of possibilities there.

If they're the Sportsman heads, which is what they look like, there's a bunch of things that are, and have to be, very much like stock, because those were designed to "replace" certain stock heads, in certain classes of certain types of racing, wherein certain modifications are not allowed or they must retain certain stock specs. Kinda like the days when I built motors for the 4410 2-bbl carb claimer class, or the .390"/.410" valve lift class (duration wasn't specified... heh-heh-heh-heh), or the 1.25" valve spring class, or had friends (it was pointless to build motors for them) who ran in the F70-14 right rear tire "bomber" class. Those kinds of things are how sanctioned non-professional "sportsman" series keep their playing fields even and limit the potential effect of cubic wheelbarrows full of $$$$. I can't remember all the specific things that weren't forbidden / mandated in the classes that those heads were directed towards; threaded studs may have been allowed, or maybe not. I don't think so but I just can't remember. Pretty sure guide plates weren't allowed. Pretty sure they had to use the stock rocker guide system at the time, which was still the hole through the head.

We'll have to wait for him to pull the rocker off and show us the bent/broken push rod, which it most assuredly is. Then maybe tell us WHAT "Comp Cam" he has, what valve springs those are, and so forth, so we can figure out if his combo is even survivable, or if he merely replaces the parts that are farkled right now, whether it'll do the same thing again either in the same place or elsewhere the next time he runs it. Doesn't look like it's been run all that much; the rocker ball seats aren't even turning blue yet, which only takes a few hours of run time to build up that much heat. Sometimes happens on initial startup if everything else is real aggressive. So I'm suspecting it's what I'd consider an "infantile" failure; happened when the motor was just a newborn; as in, something was amiss in how it was built, and it failed right away. He didn't tell us that either.

 

Here is my World Products S/R Torquer 305 heads. And they ARE heads that were modified and destined for a racer. I got shipped these by mistake instead of what I ordered. I have screw-in studs, but no guide plates. Still guided by the double-D slots in the heads. Sportsman heads were for the 350s, IIRC.

 

Yeah the S/R Torquers were/are a different beast yet again... they did indeed make some of those in a chamber size appropriate to the 305. The Sportsman and Sportsman 2 were originally in 64cc and 76cc varieties to replicate 186 or 882 castings that were specifically required for abuncha non-pro series, as the source of 186 especially dried up as time went on. I don't think the S/R were specifically targeted toward complying with sanctioning series rules originally, but I could be wrong.

 

Hey again guys, some more pics.
But, @sofakingdom - you are right on, the pushrod is definitely bent. As stated, the heads are WP S/R Torquer 305.
Regarding all other detailed specs, to be honest, I cannot recall much - it has been 23 years and Im now an old dude 😂 But, you are also right that the car is not driven much. Approximately 15000 miles total over those 23 years! Never driven hard, raced etc. - just a cruiser.
Engine was out 7 years ago for trans rebuild, and all gaskets were replaced, but that was it.

Let me know if there’s more pics info needed.

 

hmmm
pushrods just dont bend.

and id bet money that valve stem is bent as well.

youre going to be safest to remove that head and send it out to get checked.

maybe the valve kissed a piston causing this.
15k miles is still new, but id like to see coil bind/PTV specs and the top of the piston.
maybe broken valve spring?

very hard to guess without having the parts in front of us.

 

stainless valves in iron guides will often seize-probably not the case here,but did happen to me once with similar results-learned stainless valves need bronze guides...

 

+1 for pulling the head and letting the machine shop take a look. The pushrod guide slot in the head looks worn and I would bet that the valve guide is also worn from side loading. Who knows how long it ran that way before the rocker slid off of the valve stem, alerting you that there was a problem. That valve guide was probably too tight to begin with.

My heads have thin wall bronze liners installed. I can't remember if the heads came that way when new. But if yours did and the wear is minimal, then you will probably get very lucky by only having to replace the guide liner. If the guide slot is worn, then you can have that hole drilled out to a larger size and use a self-guiding rocker for that valve only. You should be able to purchase only one rocker, instead of a full set.



Comp Cams


PRW

 

These are the heads that were installed in about 2002:

 

Hey again guys,

Finally got around to getting the head pulled. But, before doing that, I did take a risk on a quick fix by just replacing the rocker and bent pushrod, but still did not run right.
Anyways, pulled the head today and first - there is no sign of the valve touching the piston. However, the valve is binding bad in the valve guide, so I suppose that is where the problem started.

And, please ignore my ignorance, but these heads have iron valve guides - can they still be replaced by bronze guides ? If so, how do I ensure I get the right ones ?
I'll have a local machine shop take care of the work, but any thoughts for the right way to fix this - and pointers for what guides to get would be great!

Thanks!


Ken

 

Use an oversized stem new valve (+.003", depending on the wear) and hone the guide to fit.
Then have the valve seat touched up. And you need 1 new rocker.
Drill out the pushrod guide slot in the head to be able to use a self-guided rocker in that position only.
Refer to post #14 above.
OR
Your guides just might have bronze liners. Here they are: Rapid, Bronze Valve Guide Liner, 11/32", Each - Competition Products
If so, then just replace the liner, hone, and use a standard 11/32" stem valve.
Not all machine shops have the guide liner replacing tools.

Repair only what is broken. Don't replace the rest of the guides in that head. Totally unnecessary.

 

Awesome, thanks for your help man - appreciate it 😊

😉
Ken