rocker block stud pulled out of head

[p aiello]

did not get to put the valve covers on yet cause one of the studs pulled out of head what size heli coil do I need the nut side is 5/16 fine but the lower thread looks like course but I can't get a dey on the stud is it 5/16 course? I think I will need a new stud cause I forced the dey down a bit pat

[58flh]

Paiello----This can be fixed---Find the size thread that it actually is by comparing the stud to a bottoming tap.After you find the size -Use a Thread chaser tap---It does not CUT or remove matieral from head.What it does is repairs any scraped threads by rolling them back into place.Dont cut the stud eighther!--Just Handrun the die over the stud.Get a Heli-coil for the correct size & Make-sure the stud fits into the coil before install.Using the Heli-coils tool ,use a drop of LOC-TITE on clean threads & run it home.Next run the stud home with the arm & block--Check for a free movement of 1/2-inch in either direction,& End-play should be kept to spec.Most Likely the endplay will not change!.Let the LOC-TITE set up & Install.--If the HEAD is really FUBARED!--Then you need to find a good TIGMAN/& fill the hole up & then machine everything to spec.This ofcourse you will have to do IF the HEAD is wasted!.----Respectfully----RICHIE

[p aiello]

I found out why it pulled out the Clymer manual has the torque setting for 18-20 lb but it should be 15lb so its my fault anyway the threads pulled out of head so theres no thread to repair I have to put a heli coil the stud has two different threads is it 5/16-24 nf at the nut side but the lower looks like 5/16-18nc but when I put that dey on it it goes on but not smooth you have to force it, is it a special thread ?

[Mark44]

I'm pretty sure that "dey" means "die". It took me a bit of mental gymnastics to figure out what p aiello was saying here.

As far as the thread specs for that stud, I'll take a look at my Palmer's and see what he has to say.

[caschnd1]

I used this 5/15-18 repair kit to fix my pulled rocker stud. Don't use a die to try and match your thread size. You may end up shaving your stud a little and making it fit loosely.

-Craig

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[old.wrench]

p aiello
You are correct about the thread size being 5/16"-18tpi. where the stud goes into the head.
Also, keep in mind that the original stud and good quality replacement studs are cut with an "interference" thread on the 5/16"-18 end that goes in the head.
That means that the threads are cut just a little bit bigger, with an "interference fit" so the stud fits more tightly in the head.
You will still use a regular 5/16"-18tpi heli-coil kit like the one that Craig pictured for the repair.
I've used the Colony brand replacement replacement studs in the past and they work excellent.

Geo.

[Larry]

You may have a problem with a helicoil and interference fit. Be careful, go slow.

[james]

I prefer time serts over helicoils

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Jim

[RooDog]

This is an interesting explanation video for the Time Serts. Helicoils are self locking because they self expand when installed. I am sure both of these systems have their preferred applications and in this case with the interference fitting stud's threads the Tim Sert is probably the way to go. I have never used a TS but have had great luck with Hilicoils in most every app I have used 'em on.
PS: Toss that Cylmer misinformation manual and get a hold of both the factory Harley Service and Parts manuals, you'll be glad you did and this would never have happened...... RooDog

[Buddhahoodvatoloco]

A million times over, a little more work, but done right, done once. I prefer time serts over helicoils

[RooDog]

One of the dumbest thing ever done by the MoCo was to use short Helicoils in the sparkplug holes on early Shovelheads. Never had a problem with the cast in SP threads on a Panny. RooDog