Valve problem(still!)

[Sluggo]

Am I seeing what I think I'm seeing?

Are those not early heads with late valves?

From Mustang Steve's website....
Early 289 heads had valves with short tips (about 1/16 to 1/8" above the keepers) that used non-rail type rocker arms. They had the shorter 289 style pushrods and rocker arms without the rails that capture the stem of the valve keeping the rocker arm from sliding off the side.  The pushrods went through holes in the heads that fit up close to the pushrods, keeping the rocker from sliding off by holding the pushrod in line.  Those type heads had adjustable, press-in studs.  Later heads used rail type rockers.  The hole in the heads that the pushrods (longer 302 pushrods) go through is round, the valve stems protrude about 1/4" above the keepers and they were non-adjustable.

[B67FSTB]

Isn't it best to check if the camshaft is synchronized with the crankshaft?

Maybe it is 360° wrong ?! my opinion.

[tarafied1]

Isn't it best to check if the camshaft is synchronized with the crankshaft?

Maybe it is 360° wrong ?! my opinion.

wouldn't 360 be okay? Maybe you meant 180? Anyway, it ran so it's probably not out of time. I think the coil bind or maybe valve height vs push rod length is more likely. It does seem there are some mis-matched parts...

[B67FSTB]

4 stroke engine , 360° is one turn , every two turn you have a combustion in the same cylinder.So when your cam is NOT synchronized with the crank , the piston could smak an open valve. See broken rocker which is broken on the valve side.
I would recomment to turn over the engine for at least 10 times ,by hand or by starter , in little steps so oilpressure can built up.
Your engine builder did made a big mistake IMHO.

[whisperer]

 Those are the wrong retainers. They are compressing the valve springs too much and you are breaking rockers because you are running into coil bind. It's amazing that you haven't broken other rockers also. I would check the rest of them for cracks. Could be when those heads were assembled that valve spring was shimmed just a little more because of a variance in the depth of that valve seat grind.
 If it was the rocker slots binding on the stud then the rocker would break between the pushrod and the rocker slot instead of between the rocker slot and the valve like yours did.
 Your 289 heads guide the rocker by using the pushrod slot in the head. They are effectively guide plates. You should not need shoulder rockers, although if they don't hit the retainers they won't hurt anything, still it's not the right way to do it.
 Those heads have adjustable valves instead of positive stop "stepped" studs. If someone is getting confused they may crank down the rocker nuts thinking they are positive stop studs and run the valves into the pistons.
 If this guy is going to bring you a good set of heads I'd take them if I were you. Be forewarned about the expertise of whoever put together the heads you have now.....

[tarafied1]

4 stroke engine , 360° is one turn ,

that's what I'm saying. If you rotate the cam 360 it will be exactly in the same place... the cam turns 2 to 1 to the crank so 180 would be a problem, not 360.

[Dne']

hi all, I've been away for a few days.  I also paid attention to what Sluggo wrote," early model heads with late valves"  Whatever the reason, heads are being built~ at least that's what I've been told. I'm going to write Herb and see what the next heads are coming from.  A point that even Herb stated, that other rockers weren't breaking! Definitely would have solved the case a little quicker if 6 or 7 rockers had broke! lol  I'll report back on what the heads are coming from.
dne'

Those are the wrong retainers. They are compressing the valve springs too much and you are breaking rockers because you are running into coil bind. It's amazing that you haven't broken other rockers also. I would check the rest of them for cracks. Could be when those heads were assembled that valve spring was shimmed just a little more because of a variance in the depth of that valve seat grind.
 If it was the rocker slots binding on the stud then the rocker would break between the pushrod and the rocker slot instead of between the rocker slot and the valve like yours did.
 Your 289 heads guide the rocker by using the pushrod slot in the head. They are effectively guide plates. You should not need shoulder rockers, although if they don't hit the retainers they won't hurt anything, still it's not the right way to do it.
 Those heads have adjustable valves instead of positive stop "stepped" studs. If someone is getting confused they may crank down the rocker nuts thinking they are positive stop studs and run the valves into the pistons.
 If this guy is going to bring you a good set of heads I'd take them if I were you. Be forewarned about the expertise of whoever put together the heads you have now.....

[buening]

This thread may help about the later valves and early heads:  http://forums.vintage-mustang.com/vintage-mustang-forum/589150-non-rail-rocker-rail-type-valve.html

Short answer is depending on the date code of your head the long tips may indeed be correct with non-rail type rockers. 

You definitely don't "have the wrong heads".   A 289 head is a 289 head.  There are differences like the 289 Hipo heads but even those heads wouldn't cause this issue.  One good thing is you are hopefully getting a better/newer set of heads, but that doesn't really determine what the issue is. With permission of your builder, I would install another rocker on that valve and rotate the motor BY HAND and watch the valve spring. Also feel for resistance when you get close to max lift. You definitely have spring binding issues and its either too long of pushrods, wrong spring type, too thick of retainers, or a combination of those that may be unique to that valve (wrong spring at that valve).  New heads will eliminate the valves and springs, but won't eliminate the possibility of too long of pushrods or a faulty camshaft that has too much lift at that particular valve.  If the new heads result in that same rocker breaking, I'd look at the pushrods or put a dial indicator on the rocker and measure the lift to compare to another valve.

The rocker broke exactly how I would expect it to, the point of maximum stress near the fulcrum.

[apollard]

With permission of your builder, I would install another rocker on that valve and rotate the motor BY HAND and watch the valve spring. Also feel for resistance when you get close to max lift. You definitely have spring binding issues and its either too long of pushrods, wrong spring type, too thick of retainers, or a combination of those that may be unique to that valve (wrong spring at that valve).  New heads will eliminate the valves and springs, but won't eliminate the possibility of too long of pushrods or a faulty camshaft that has too much lift at that particular valve.  If the new heads result in that same rocker breaking, I'd look at the pushrods or put a dial indicator on the rocker and measure the lift to compare to another valve.

The rocker broke exactly how I would expect it to, the point of maximum stress near the fulcrum.

Gotta agree - I would rotate by hand, or have him do it to determine when the bind occurs, then why.

[Dne']

I spoke with Herb a little bit ago, basically just had installed the wrong valves! The next set of heads are from a 289(doah!) with the correct valves! Pretty much sums it up!  He like some of you may have been thinking~ why didn't more rocker arms break!? Just the one rocker breaking kind of threw off finding the correct diagnosis~! Now to fix my body so I can fix my stang!

I know this is off topic, but I have been having a horrible time for months with headaches, jaw pain, lower molar pain, ear pain, neck pain, dizziness, louder than usual tinnitus, and hyperacusis,etc.  I Had an MRI of my brain, neck only to hear, can't find anything here!  Then onto my dentist which examined my teeth, xrayed my TMJ's, "all looks ok" and sold me a night guard for 450! Just about ready to throw the towel in~  Today I got back from my ENT(ear nose throat), he said my TMJ's are screwed up probably causing everthing I listed~ so antibiotics, muscle relaxers and I requested a few Valium~ now I just need a good massage therapist! It's Hell being a human! lol
dne'

[buening]

My wife was supposedly diagnosed with TMJ by the dentist. She was having headaches and everything pointed to TMJ.  She was also stressed out with work and hated her job.   She switched jobs, stress level went down, and all headaches and symptoms of TMJ went away.  She hasn't been back but that would have been an expensive mistake to have the dentist do the night guard stuff.   I am assuming we are talking about TMJ, which is a symptom.

[buening]

Also, be VERY CAREFUL that Herb doesn't install the shorter valve stem ends and then run the rail type rockers.  If he uses those same valve spring retainers then the lips on the rail rocker will basically push just the retainer down and the keepers will go flying, causing you to drop all valves into the piston.  Not a good thing  :amaz

[Dne']

OK, heads are off! It's not really all that bad to remove these heads other than the darned heads weigh so much(for me!)! I had to use my engine crane to remove the heads like I did last time. Plus not having the fenders on is wonderful to work on the engine!  Herb will be here to help me, or me help him put it back together. I need to paint my next set of heads first, so probably be next week before I put it back together again.  Actually I wouldn't mind the re-assembly if I could get my brother to set the heads on(the brute work), I could get it back together with no problem. The crane works well to get the heads off, but may not work as well setting the heads back on.


1)I do have a question about the head bolts~ One of the shorter head bolts is very hard to turn; can I use a tap to run in the block to clean up the threads, Or should I get new head bolts? can they be purchased?

2)I know the roller rocker arms don't put much extra HP, but they look really neat, are they a worthless investment?

You all wrote exceptional replies~I do appreciate ya'lls help/advice/opinions!!
dne'

[blue65coupe]

It is advised that you buy new head bolts. 

[B67FSTB]

Always run a tap in the block where the head bolts will run.To clean up the threads so the stress on the head is equally spread over the entire head.
Lube the NEW bolts thoroughly or lay them in a boil of oil.
Check your new headgasket when putting it on the block.
It has an upside but also back/front side ,otherwise you encounter overheating problems.
( sorry for the bad english , trying to help)

[Horseplay]

As stated, you should always "chase" the threads with a bottom tap. This should have really been done when the block was bare as part of the cleaning and freshening. As it is now you need to be very careful not to have any fresh metal particles cut lose by the tap find there way into the engine.

This is done to make sure the torque readings are accurate when installing the head. A burr along a thread can give you a higher torque reading without actually applying the same level of force between the head/gasket/ and block surfaces. Oiling the head bolts also aids in accurate results.

New head bolts are always a better idea. Bolts stretch as they are tightened. Older bolts don't always recover or stretch the same leading again to inaccurate torque results.

[B67FSTB]

As stated, you should always "chase" the threads with a bottom tap. This should have really been done when the block was bare as part of the cleaning and freshening. As it is now you need to be very careful not to have any fresh metal particles cut lose by the tap find there way into the engine.

This is done to make sure the torque readings are accurate when installing the head. A burr along a thread can give you a higher torque reading without actually applying the same level of force between the head/gasket/ and block surfaces. Oiling the head bolts also aids in accurate results.

New head bolts are always a better idea. Bolts stretch as they are tightened. Older bolts don't always recover or stretch the same leading again to inaccurate torque results.

Thats what I was trying to say.Thanks Horseplay !!

[Dne']

I went to get my next set of heads today from Herb.  They're off of a '69. These heads have the round holes for the pushrods vs. the oval hole, and Herb gave me the rail rockers to go with them.  I got them home, and began running a tap through every hole, including the block. I'm glad I did because 75% were rusty or something would have caused some problems!  I'm going to look for a bottom tap tomorrow, my taps are the regular kind.  Most of the block holes were pretty rough, I'm so glad I took care of them. and Summit is also including some lube for the headbolts.  Maybe ACE hardware may have the bottom taps~
I've got new head bolts, gaskets coming from Summit racing and should be here by the weekend, but I won't be able to put the motor back together until next week.  Herb will come over when I'm ready to tighten the rocker arms; not sure how to adjust them in the initial startup.
Thanks again everyone!!!!!!

My 2 y/0 grand daughter was helping me with tapping some holes too!

[buening]

So did Herb mention these heads are from a 302??  I'm not aware of a 289 built in 69.

[Dne']

 :craz you know this is driving a little crazy~ he may have said '68, I was just happy to get the heads! I was beginning to wonder where I was going to get my next set of heads if Herb didn't come through!  If they were from a 302, would that cause any problems with bolting up?  How would I distinguish a 302 from a 289 head, if that be the case?

[66gt350]

They should say either 289 or 302 where the springs are.  The only difference I found when going from 302 heads to 289 heads on the wife's mustang is where the power steering bolts up.  The 302's have a bigger bolt hole there than the 289's.  Had to run to Ace and get a new bolt for there.

[Dne']

I just went to check, they're 289 heads, but they're different than my previous heads. The springs seem to be lowered into the valve spring seat and the springs don't look so compressed like the last head, and like I said, these have round push rod holes instead of the oval.  There are some funny looking bolt holes like where the alternator or PS pump would go , like helicoils, but not, but they are 3/8's bolt holes, looks like they could be taken out with a large screwdriver.  These heads will take the railrocker arms which Herb supplied. So, I guess I'm good to go(again)!
Now just waiting on gaskets~ the heads are now painted and ready to be installed! I hope this is the last time I have to pull heads off for a while :doh

[RustyRed]

Glad to hear your getting it resolved.  If it makes you feel any better, I discovered after I bought my GT40's that heads are heavy no matter who you are...unless you happen to be Hulk Hogan I guess.

As far as the medical symptoms your having...sure it's not tree pollen / allergy related?  I have been having a lot of the same problems but I have them every year.  It cloggs up my ears (on the left side in particular) and that makes me feel kind of dizzy sometimes...especially after a bunch of forward rolls on the Aikdio mat, LOL!  Also makes my upper teeth hurt again on the left side in particular.  It just in general makes me feel "off".

Best thing I have found for it is drink lots of water, make yourself exercise even when you don't feel like it, get a good nights sleep every night and take singular daily :-)

[Midlife]

302 heads have bigger chambers than 289 heads, which will lower your compression from 1 to 2 points.

[Horseplay]

302 heads have bigger chambers than 289 heads, which will lower your compression from 1 to 2 points.

Unless they have been surfaced (milled) which would help regain some of that compression. Older heads like these will certainly have had at least some clean-up work (surfacing) done to them. Of course, that could also affect the valve train as well. Make sure he takes the time to check clearances on everything this time around  especially looking for valve spring coil bind and proper pushrod length.