Measurement Tools

[ChrisBennet]

Originally posted by William Miller
Is that the going rate for all the heads? What does it include?
Where and how much does it cost to ship back and forth?
Is there a machine shop thread on this bbs?
Thanks!

That's what Atlantic Enterprises (NJ) and Engine Builder's Supply (AZ?) charge but I think it is on the low side compared to most places. I use Atlantic, all he does are heads. His price includes new seals and valve guides. New valves are extra. His price on valves has always been lower than my own sources.
Both places are listed in Pano.
Edit: Atlantic also tests the springs and sets the spring height and refaces the (EDIT: cylinder) mating surface. Normal head rebuild stuff but something to compare against your own time.
As I understand it, the process for doing Porsche valve guides is to heat the head up, remove the valve guide, let the head cool, measure the guide hole, machine the outside of the guide for the correct fit, heat the head up again and install the guide with some talc I think. If you want to do a first rate job you hone the guide instead of using a reamer.
-Chrisk

[snowman]

I forgot that I did measure the springs, and replaced them anyway, measured the new ones to be sure they were ok. Replace the springs if the engine has over 100K miles on it. Always check springs, new or not. Never had to resurface any mating surface for springs.

It dosen't matter if you heat the heads or cool the guides, if fact its possible to do neither and install new guides. the purpose is to make the fit easier and to reduce stress on the head on installation of the new guide. You can also do both, heat the heads, and cool the guides if you want to. As the the lube its not a big deal, any lube will do, some better than others, I prefer ones designed specifically for press fit operations. Talc is old, old, old. Do you use Red line oil or old spec Pensoil 30 wt? both work, but not to the same degree.

If you are like me I do this, not because it makes echonomic sense, but because I want to do something different, something that I can say, I DID IT, MYSELF!

[ChrisBennet]

I looked in Pano and Atlantic isn't listed but I found it in Excellence.
Atlantic Enterprises (Pitman NJ) 856 589-5577
Engine Builder's Supply (Sparks NV) 800 462-3774

[snowman]

Absolutly fab prices on dial bore guages. Only problem is that typical measurements may need 0.0001 accuracy instead of 0.0005" accuracy. EG for rod big ends, cylinders in newer engines.

[john walker's workshop]

guides need to be step drilled about 1/2 way thru, and then they can be driven out. if you just start beating on the end of the guide, it will mushroom, and then it can damage the guide bore on it's way thru, or crack the head. be careful about driving the guide thru from the spring side. many guides have a collar that butts up against the head, so if you're not careful, the collar gets driven into the guide bore. WD 40 works well as a lube for installation.

[Wayne 962]

I would WHOLEHEARTEDLY recommend against removing your own guides - leave it up to the machine shop, unless you have a set of heads to practice on, and the right equipment.

-Wayne

[snowman]

The right equipment here is a hammer and a punch, maybe a drill and bit. Suggest you try a couple and tell what you find. It ain't rocket science. Really.

[5axis]

Just a heads up. Enco is offering a 81pc grade B gage block set for $60.
It's a cheap way to really know what your measuring and test /develope your feel.

[ChrisBennet]

Originally posted by 5axis
Just a heads up. Enco is offering a 81pc grade B gage block set for $60.
It's a cheap way to really know what your measuring and test /develope your feel.

Thanks for the heads up.
-Chris

[William Miller]

It's been awhile....
I found a new way to easily remove the valve guides. The picture in Waynes book pg 59 3-22 along with some ideas from another mechanic resulted in the following very simple process:

Wayne your book has the picture pg 59, but not the process.
The special tools cost me about $15 at Sears and the hardware store.
1/2" galvanized gas pipe coupling (I found one that was about 1-1/2" tall and the ends were very flat.)
7/16" x 14 tap tap
3/8" drill bit for 7/16" tap
Assorted lengths of 7/16" grade 8 hardened bolts (1"-3")
10-12 7/16" washers.

I'don't have pictures so try and follow me.
If you have Waynes book flip to page 59 picture 3-22 to 3-24
On the spring side of the head the valve guide sticks out 13.2 mm.
There is the round flat spot on the head that the valve spring seat (washers) sit on. This is perpendicular to the valve guide.

1. First I drilled and taped the inside of the guide for a 7/16 X 14 bolt.
2. Place the valve spring seat on the head upside down. This was just used as a spacer.
3. Place the pipe coupling on top of the spring seat.
4. Put about 10 washers on top and thread the bolt thru the washers and the pipe coupling. (You have to experiment with different sized bolts , washers etc.)
5. Snug it up getting everything aligned.
6. I tightened the bold with a 5/8 socket and 1/2" breaker bar. This pulled the guide out of the hole.

(I had to do it in 2 steps because the threaded part of the bold was only about 1" so I had to get a shorter bolt for the 2nd step with fewer washers.)

My first fear was that I would strip the threads in the guide. (I needed to put a substantial amount of pull on the end of the breaker bar to get it going. The first one took me about 10 minutes. The rest took about a total of an hour because I was trying different size bolts and extensions to make it go easier and faster.

I learned one trick. The female end of my 1/4" socket extension fit right on top of the tap upside down and the male end went right into the tap handle perfectly. I was able to start the tap without the extension but after about 9-10 turns the studs on top of the head were in the way. The short extension cleared the studs.

One caution: On one of the guides the tap cut thru the outside edge of the guide. I guess I didn't drill perfectly straight. It made some minor scratches on the inside of the guide bore. Nothing to worry about.
The next time I think I might get away with a 3/8 bolt and tap. Might even skip the step of drilling out for the tap. The inside diameter of the guide is 9mm plus whatever wear. So there is probably a tap size that uses a 9mm hole as a guide? The bolt in Waynes picture looks much smaller than what I used.

I was told of a simular method where you tap the guide, insert a bold and use the spring seat surface and a 6" piece of pipe. Put a drift in the end of the guide (Combustion chamber side) adjust the bolt to hit the end of the drift and press it out of the top.

I don't have a press. I have a big drill press and thought about using that. I think it would probably work. I was concerned about juggling all of this to get it into the drill press square.
When I went to the hardware store to find a piece of pipe (I was looking for a 1" gas pipe nipple 6" long.) They didn't have one long enough. I was thinking a coupler would make up the difference and also make the setup adjustable. That's when this idea got in my head.

Anyway it worked for me. I learned something and DID IT MYSELF!
I measured my guides and determined that they are standard sized.

I stopped at the machine shop this morning to get a quote on installing the guides and cutting the seats. The owner said my seats were good to cut and he quoted $40 per head for a tripple cut and to install the guides.
So I also saved a few bucks at the machine shop.

I might install the guides myself.
I was wondering how to get the depth right. The spec. book say's they should extend 13.2 mm above the head. I'm thinking I could use the spring seat and several of the spring adjustment washers to get very close to the 13.2mm. I would press the guide in part way (After heating the head.) stack the spring seat and washers on (13.2mm worth.) press the guide the rest of the way until I hit the stack.

With the head heated how much pressure is needed?
I know I will need a drift. Should I be able to push it in by hand if I lean on it real hard? Stand on it? Press it with my drill press? Do I need a hydroilic press?