Head studs - I'm fixin' them!

[tripm]

I figure if I don't publicly declare I'm fixing this car that I've had for ~10 years, I will never fix it. After a lot of work I got it running about 5 years ago, only to find a bunch of head studs were broken.

My goal here is simply to be able to drive the car, a 1980 911 SC. I'm giving myself until May 1 to complete this.

I have the motor out and in my basement. Next up is to order the tools for removing the cams. I had them bookmarked online to order and then lost the bookmarks.

A Porsche mechanic has offered to help but I got this far on my own and I feel like I will let myself down if I don't finish this on my own.

Ok, public declaration complete. Next up, search for the tools again.

Thanks for letting me share.

[tharbert]

Declaration noted. Ahhh, errrr, what's is gonna cost you for not getting this done? I'd say, a round of suds and wings for any pelicans that show May 3rd for the Friday night barbecue you'll be having?

[tripm]

Ok, here she is. Sweet!



tharbert, if you'd like to ride that fancy bicycle to NH on the 3rd, I'll buy you some wings and beer regardless of whether the 911 is finished.

Here is a fascinating album of the 911 with the engine out.

https://plus.google.com/photos/118310977721675433324/albums/5846811309019300865

[tripm]

Here is where the process is at now. Special tools needed.

[Josh D]

What's that on the floor? A couple of transfer cases?

[fastfredracing]

All you need is a big socket, and an impact gun, and you can blast those nuts off. I think 46mm? if I remember correct. That way , while you are waiting for the tools to arrive ( which you will need for re-assembly) , you can be getting at those pesky studs. Good luck, doing good so far

[tepps]

be careful with impact gun. I once broke the end of a cam off(maybe on a 2.2) Installing the big nut. Obviously a learning experience.

[fastfredracing]

Yep, only use the gun to loosen the nut. You will want the tools for re- assembly.

[tripm]

Originally Posted by fastfredracing

Yep, only use the gun to loosen the nut. You will want the tools for re- assembly.

Fred, looks like the cam tensioner has to come off first I guess? Looks like just a few bolts for that? Thanks for the pointer. I'll pick up a socket tomorrow.

Josh the eagle eye. I just counted - three xfer cases in the photo and a bonus bell housing.

[SCadaddle]

It was just about where you are now in the dis-assembly of your engine that I kind of wish I had spent a few minutes/hours/days and checked the cam timing---just to see where it was---before taking it all apart. Good Luck!

[fastfredracing]

I think the socket will fit right in there without interference to the tensioner. I would want the tensioners still on when I went after that big nut with the impact gun. Do not want to take any chances of moving the cam, and bending valves. It should take just a few light blips of the trigger to loosen it.

[Smoove1010]

You might want to loosen all of your rockers and shafts before loosening the cam nut - that's the best way to minimize the chance of valve-piston collisions. Try this order:

-loosen rockers as far as you can
-use impact wrench to loosen cam nut - don't let the engine spin backwards - have someone hold the crank with a breaker bar
-compress chain tensioners with clamp, remove
-remove cam sprocket, washers, retaining plate, etc., etc.

As SCadaddle noted - I did a cam-timing dry-run before disassembling, found the timing was retarded outside of spec, which I since learned is due to chain "stretch". This was a really good way to get comfy with the cam-timing process.
Good luck!
GK

[304065]

Please don't use an impact wrench on your engine anywhere.

You have to have the proper tools to tighten the nut, so you might as well make the investment up front. Then use them, along with two breaker bars, to carefully loosen the nut. One goes on the crowfoot, the other goes on the cam.

If you use an impact wrench you're asking for the chain and sprocket to resist the torque, because there is no way to hold the cam with a socket over the nut. That's asking for trouble with the chains and the sprockets, to say nothing about the possibility of snapping the nose off the camshaft.

Also, a 46mm socket isn't exactly cheap. If I had it to do over I would buy Stomski's tool, it looks like a slick solution.
911 Cam Nut Tool

[fastfredracing]

O.K. so I made up a little video today to debunk the myth that loosening the cam nut/bolt on 911 camshafts with an impact gun puts too much stress on the chains. I had a few old pitted cams laying around so I used them as guinea pigs.
I torqued up the big nut with the factory tools, then removed it with the impact gun. As you can see, I am holding the cam with only my hand muscles resisting the turning of the cam from the impact gun. It easily comes loose with out much too much force trying to turn the cam. I am quite sure that if my girly hands can resist this force, then the timing chains and sprockets are easily up to the task. I would never recommend tightening them this way.



So, how are you coming along so far?? Heads off yet?

[szyzygy]

Video is private :\

Originally Posted by fastfredracing

O.K. so I made up a little video today to debunk the myth that loosening the cam nut/bolt on 911 camshafts with an impact gun puts too much stress on the chains. I had a few old pitted cams laying around so I used them as guinea pigs.
I torqued up the big nut with the factory tools, then removed it with the impact gun. As you can see, I am holding the cam with only my hand muscles resisting the turning of the cam from the impact gun. It easily comes loose with out much too much force trying to turn the cam. I am quite sure that if my girly hands can resist this force, then the timing chains and sprockets are easily up to the task. I would never recommend tightening them this way.



So, how are you coming along so far?? Heads off yet?

[KTL]

Originally Posted by szyzygy

Video is private :\

That's because he's just toying with us, hiding the fact that he snapped the snout off both cams and wants tripm to suffer the same fate...........

[sailchef]

I will be watching this thread closely. I have been collecting courage to do the same project. My bucket ( of courage) is about 3/4 full. This thread could be just enough to get me started.

Good luck, and please, more pictures / details of the procedure!!

[fastfredracing]

Does the video work now?

[KTL]

Nope

[pete3799]

Still private Fred.