Sealing rings at top/bottom of cylinders

[SGKent]

[RalphWiggam]

[raygreenwood]

A couple of items.....if you have not gotten too far....i will dig out my instruction sheets and get them posted.

Deves make excellent rings....but just like anything else...check each edge at the gap carefully for burrs.

Also....and I know you are already done with honing.....but for future reference from other comments.....do not have someone hold a cylinder when you hone it. It MUST be bolted down.
If its being held....you have movement from the in/out thrust and that changes the angle. Any hone expandable or otherwise needs to stay axially centered or it changes stone pressure.

Is it a big deal if you are just putting a new profile on it?.....yes and no. It can be or not. 50/50 chance. It depends on how much misaslignment there was during honing.

As for angle of cross hatch.....its interesting.....I just carefully looked at photographed four sets of cylinders. Two sets were brand new....a mid 90s Cofap 1.7 set, an early 90s CIMA 1.8L set and two sets of lightly used 1.7L KS cylinders.

The actual factory cross hatch angles varies.....somewhat widely....not just from set to set but within each set. They can range from 35°-ish to 45°-ish all the way up to close to 60°-ish.

Cross hatch angle is just not hugely important by itself. What is far more important is cross hatch peak, valley and width size....and consistency with a given cylinder.

In fact....more than one article from ring companies over the years has noted that they actually recommend a 55°-60° cross hatch for engines with horizontal cylinders. From the fact that several of these cylinders are close to 60° and ran fantastically.....its at minimum not a problem.
The difference that hatch angle can make along with peak to valley height of the scratch marks....is different levels of drag on each piston. Not a huge problem in the long run.... but it can make one cylinde break in much faster or slower than another. Ray

[69BahamaYellow]

Hello Ralph,

Yes, I was running a single thrust bearing on my original Webcam install. Now that I think about it, that may be one of the reasons people miss the runout issue on the thrust flange. If the high spot happens to be positioned on the side with no thrust bearing, when you're checking axial play in the cam, you may never notice it.

[RalphWiggam]

Got my rings, pistons, cylinders, and heads installed. Setup my ring orientation per the Wilson book and the Deves instruction sheet. Used rtv red on the bottom of the cylinders and under the spacers. Used a straightedge to make sure the tops of the cylinders were dead flat and sanded the spacers a little to get everything perfect. I torqued the heads to snug / 10 / 15 / 20 / 23 in the correct patterns. I used curl t under the head washers and the nuts in the valve section. Let it sit for a few hours and then reconfirmed the 23 again.

Last night I got the t4s solid rocker spacers all adjusted for length and the t4s HD rocker studs installed. My rocker shafts are super tight on the new studs. Also polished all of the rocker shafts and stand faces with 2000. I tried to use an old pushrod to start doing geometry but it was too long. I need to buy an adjustable one to move forward. I'll see what else I can slap on the longblock while I'm waiting for the adjustable pushrod.

[raygreenwood]

[Xevin]

Wow 18 pages of you guys helping Ralph You guys are awesome
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Keep on Busin'

[RalphWiggam]

[Busstom]

Time for a little painter's mask over all those ports and other inlets (I realize none of the valves are open YET). And spark plugs slightly screwed in until rocker geometry time. That beauty looks vulnerable at the moment.

[RalphWiggam]

[SGKent]

blue tape is your friend. So is green, clear and duct. Sometimes people think we are anal because the first thing we do is tape up the block and ports etc but I promise you, more than one of us has done that accidentally.

Want to freak a friend out who just buttoned an engine up? About 6am when you are exhausted from working on it all night lay a spare part that goes inside the engine on the workbench when he isn't looking then five minutes late pick it up and ask what is this? Get ready to run if he has a wrench in his hand
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[raygreenwood]

[Clatter]

I swear it was a crook who pranked me..

A tin screw somehow 'fell' down the breather chimney into a long block I built.
And I heard it chewing up the front of the case and the back of the oil pump and front of the cam gear.
it made a racket, and freaked me right out!

Started it back up,
It was quiet and normal.
Drove it for years.

Wish I woulda saved that screw I found in there later - something to see!
I still have the crank gear - I'll post a pic if I remember.

Tape up that breather chimney!
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Bus Motor Build

What’s That Noise?!?

[bsairhead]

A head hut on a type 1 will fit thru a push-rod tube.

[SGKent]

[RalphWiggam]

I got an adjustable pushrod today and started doing the valve geometry. I have a few questions:

1. The adjustable pushrod is really only for figuring out the length I need to cut my cromoly pushrods to, right? It doesn't really have anything to do with the geometry..?..

2. The geometry is set using rocker shims after making sure the adjustable pushrod is the correct length...?

3. I am using porsche swivel feet adjusters. When at TDC for a cylinder I should back the swivel foot adjuster a few turns off of bottoming out on the rocker and then take up any slack with the adjustable pushrod? This is my pushrod length?

4. After that, measure my full valve travel and half it. Go to that halfway point and see if the adjuster is in line with the valve stem. If not (it isnt), shim the rocker stand until it is. Right?

Is that it? Do I need to measure every valve for geometry or just 1 per cylinder? Do I need to measure pushrod length for every valve or just one per engine half?

[Busstom]

I haven't yet set rocker geometry on a T4, but I'm installing swivels as well, and I'll just tell you something I heard: when I ordered my modified pushrods (for added clearance when using swivels) from FAT, Ron said I'd never achieve optimum geometry due to the lack of space under a T4 valve cover. So I'm not sure what to expect yet, but it will be interesting to hear some other responses from those using swivel feet.

[raygreenwood]

[RalphWiggam]

My stock aluminum pushrods are too long.

So step one is to set all of the swivel feet 2.5 turns off of bottoming out? Is that a good number?

[raygreenwood]