When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I'm getting ready to install new head studs into my fresh block. What is recommended to be applied to the threads from the stud to block? I've read, liquid pipe sealant, Loctite, heavy grease.... what is best? what brand?
I saw those instructions when you posted last time -- i.e., that you need to tighten before it hardens (which, of course, a non-robot could never do). I wonder if that's why the factory seemed to use an excessive amount of the stuff -- so that it would stay wet long enough for the factory to get the studs in, the gasket and head on, and the nuts torqued? Even with automated process, it seems like that would take a bit...? Just seemed like they used way more than actually needed, and have always wondered why.
I saw those instructions when you posted last time -- i.e., that you need to tighten before it hardens (which, of course, a non-robot could never do). I wonder if that's why the factory seemed to use an excessive amount of the stuff -- so that it would stay wet long enough for the factory to get the studs in, the gasket and head on, and the nuts torqued? Even with automated process, it seems like that would take a bit...? Just seemed like they used way more than actually needed, and have always wondered why.
Is there really an excessive amount? The entire thread section is covered, but typically no excess. Granted, they're a bitch to remove. //// 1/12/17 second thought: yes, it is excessive since the job of securing the studs could be done with a drop or two of red Loctite rather than what Porsche has done./////
I imagine with an automated system, the studs go in (all 10 at once?), the head and gasket go on, and the washers and nuts get torqued as a unit. It COULD be a short time overall....
Last edited by michaelmount123; 01-12-2017 at 10:54 AM.
Reason: 2nd thought noted above
The price is very reasonable. What procedure is used with this? Set time? How much to use on each stud? Any tips?
Extreme Pressure Lube (EPL) is a very thick 'anti-seize'. I use it on 944 head studs, spark plug threads, and the like. The reason it's suitable for the 944 head studs is that its viscosity will hold the studs from turning when the nuts are torqued - if the top threads are clean and properly oiled.
There's no wait time after application. Use the factory torque spec if you're using a factory type head gasket. If you're using a Cometic, use the factory sequence and torque the nuts to 65-70 ft. lbs. in three steps. Fourth step is to go over the sequence a final time at full torque since the embossing on the Cometic slowly compresses and you might find the center studs loose.
There's also benefit in being able to easily remove the head studs next time the engine is apart.
I saw those instructions when you posted last time -- i.e., that you need to tighten before it hardens (which, of course, a non-robot could never do).
Why not? Loctite red needs 24 hours to fully bond, you have at least half an hour to apply pressure and it will still allow threads to touch ie squeeze excess out of the loaded area.
Loctite red is perfectly fine.. If you don't intend to remove them ever again.
Is there really an excessive amount? The entire thread section is covered, but typically no excess. Granted, they're a bitch to remove. //// 1/12/17 second thought: yes, it is excessive since the job of securing the studs could be done with a drop or two of red Loctite rather than what Porsche has done./////
Exactly, that's what I meant by excessive. My back-up theory is that they used that much so that it acted as a sealant in addition holding the stud in place. The Loctite instructions say to coat the whole thread when using it to seal threads, which is what Porsche did. Maybe Porsche was worried about corrosion and/or fluids getting under the studs?
I installed the head and main studs and they look good. I did notice some of the studs on the head side seem like they can spin fairly easily. I don't feel any slop in the thread or wiggle to the stud but it doesn't take too much to spin it with your fingers. I figure stud stretch would help this and I'd imagine if the stud would spin a little when torquing it probably wouldn't hurt, there seems to be enough spacing under the stud to not bottom out if it does.
Did you use the grease MM recommended to prevent them from turning? You really don't want them to turn when you torque the nuts. They may get too low, you'll alter the turning friction and torque value, and you'll put a lot more wear on aluminum threads in the block.
Did you use the grease MM recommended to prevent them from turning? You really don't want them to turn when you torque the nuts. They may get too low, you'll alter the turning friction and torque value, and you'll put a lot more wear on aluminum threads in the block.
yes I did. There is resistance. But I can turn the head studs with my fingers. I scribed lines on them to see if they rotate or not
01-11-2017, 09:23 AM
Head Stud Question
