The Canary Files: 1969 911T reworked.

[edmayo]

To measure piston to head, and piston to valve clearance use kids modeling clay. For piston to head put some clay on piston top, install a head, lightly tighten down, rotate crankshaft several times, remove head and check thickness of clay. .055" or more is good. For piston to valve install pistons one thru three, put clay on valve pockets of number two, install valves in # 2 head, install intake only in # 1 head, assemble that side (minimal hardware, hand tighten is all you need) install #1 intake rocker, time cam, once cam is timed install rockers for # 2 valves, rotate engine several times. Disassemble and read clay thickness in valve pockets, minimum depth of .070" and minimum side clearance of .020." Some will say you can get by with less clearances, that's true, all depends on how exciting you want to be!!!

[kav]

To measure piston to head, and piston to valve clearance use kids modeling clay. For piston to head put some clay on piston top, install a head, lightly tighten down, rotate crankshaft several times, remove head and check thickness of clay. .055" or more is good. For piston to valve install pistons one thru three, put clay on valve pockets of number two, install valves in # 2 head, install intake only in # 1 head, assemble that side (minimal hardware, hand tighten is all you need) install #1 intake rocker, time cam, once cam is timed install rockers for # 2 valves, rotate engine several times. Disassemble and read clay thickness in valve pockets, minimum depth of .070" and minimum side clearance of .020." Some will say you can get by with less clearances, that's true, all depends on how exciting you want to be!!!

Thanks Ed! I've bought myself some modelling clay!

-Kav.

[kav]

Hey, Kav . . .

. . . nice work. And great work-space, too. Did you do any balancing? . . . rods + pistons, crank, flywheel, etc?



More, please




..........

The short answer to that is no. I'm not building a race motor and I'm not sure I wanted to go that deep into the rabbit hole. Hopefully we'll be in the zone.


-Kav.

[LongRanger]

. . . short answer to that is no. I'm not building a race motor and I'm not sure I wanted to go that deep into the rabbit hole . . .

Kinda surprised by this

Years ago, I had a VW Type III motor being re-built. I'd found a new case, gave it to the Mech, then asked for my crank/rods/pistons/etc to balance

He looked at me and asked . . . 'why would you do that? It's a boxer -- nothing to balance'

I kinda ignored him, then took everything (even the fan assy) down to Hitchcock in Long Beach. Took 'em a week-or-so, cost ~$200? -- hey/it's been 30 years . . . then took everything back to Dieter's to build-up. Just shook his head when I turned-up, finished building the engine

But THAT motor? . . .

I spent zero money on dressing it up, refinishing the engine tin or adding anything bright + shiny; just cleaned-up and used whatever was already there --- but, when it was done? . . .

. . . unless you were watching for a faint tremble in the exhaust pipe out the back? --- or you were physically touching it? . . .

. . . you could not tell that that motor was running

No 'race motor' --- had maybe 60 HP tops? . . .

. . . but that was just about the smoothest/sweetest running air-cooled anything that I've ever owned/operated




Dunno what proper balancing goes for these days, but when --- the time comes? . . .

. . . I'll do it again



..

[kav]

Well I got busy with work again and spent the summer working in London. It was great to be able to see my extended family every weekend, eat wonderfully crap British food and drink many pints of warm beer but terrible for building Porsche engines in California!

It's time to get back on track and get this thing done!

We left off with the short block complete, it's time to build out the top end! I made a little video of the process.

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Everything is laid out on my clean tray ready to build out the top end of the engine.



I bought a set of JE 81mm pistons with a compression ratio of 9.5:1. The cylinders were bored and honed to match.



Firstly I will gap the piston rings in the cylinders to 0.014" for the first ring & 0.016" for the second according to the spec sheet that came with the pistons.



I bought a piston ring filler from Amazon.



Measuring and setting the gap.



Oil ring and other rings get installed.



And then installed in their corresponding cylinders with a piston ring compressor ahd a light tap.



Time to measure the deck height, the distance from the piston to the top of the head. I'm looking for 1.25mm - 1.5mm. I install a 1mm barrel shim to start.



Blobs of clay are placed on top of the piston (No circlips are installed yet on the wrist pins). I have no idea where to but these things!



We'll install the heads on cylinders 1 and 4 and crank the engine over to crush the clay. We'll take it all apart and measure the thickness.

[kav]

I got a reading of 2.2mm, so according to a bit of math I should use the 0.25mm barrel gasket and I will be in the zone.

Time for another go! and the blobs on top where not crushed so we'll do away with those! I got a reading inbetween 1.25 & 1.5mm, we are all good!



I bought the Stomski Racing Circlip injection tool.



Takes a bit of getting used to but I install all the circlips on the right side of the pistons along with the 0.25mm barrel gasket. I use some Curl T on the base gaskets.



Installing the wrist pin, Light tap. The engine is covered in cling wrap, not that I don't trust Mr Stomski.



Ready to inject!



Boom! snaps right in! Bloody fantastic tool! I called Mr Stomski and told him!



All the pistons and cylinders installed.



The heads are torqued down.



Checking the heads are level to eachother, and they are.



With that we are done with the top end!! Moving on!

Lily and I are going to Rennsport and would love to say hi and meet other Early 911'ers as we wander around and watch the races so please give us a wave!



Hopefully see you there!!

Cheers!

-Kav.

[kav]

More work on the engine rebuild, cam housings, camshafts, timing chain housings and the sprocket alignment. I had a couple of issues, firstly I'm not very skilled with the crows foot wrench for the sprocket retaining nut. I really struggled to get it to 110ft-lbs multiple times without the wrench slipping off, so I ordered the Stomski racing cam nut tool. I also didn't realize the cam sprocket shims were 0.5mm and not the 0.25mm as described in Waynes book but all worked out and I'm ready to tackle the cam timing next. Wish me luck on that one!

I made a little video of the process.



Clean cam housings, cam shafts with the E-cam grind, oil return tubes, o-rings and all the hardware laid out on my clean tray.



New oil return tubes installed, when I ordered them they were yellow zinc and when they arrived .... they weren't. I loosened the head stud nuts to give myself some wiggle room for the cam housings.



Installed the cam housings dry, no Loctite 574 yet as I need to measure for the valve to head clearance. It all needs to come apart again.



Torqued the cam housing nuts first then the head stud nuts before trying the cam shafts in their housings, both spun freely (thank God!)



Everything I need laid out on my clean tray, parts, gaskets, 0-rings and the tools to do the job.



Installed the timing chain housing with a dry gasket and the chain ramp with the short end facing in.



Installed the camshaft end plate with paper gasket and o-ring, large washer bevel side in and 3 shims. The woodruff key give me some grief even though I test fit it on the bench. Sprocket flange over the camshaft.



I got confused about the thickness of the shims, the book says 0.25mm but they are 0.5mm. I started with 3, went to 4 and then went back to 3 on the right side!



Tightening the retaining nut to 110ft-lbs multiple times as I swapped the shims was very difficult with my novice skill levels using the crows foot wrench, I've ordered the Stomski Racing cam nut tool for the next step.



Measuring the sprocket alignment from my straight edge. The camera tripods were a set of helping hands and worked out great. The measurement on the left side was bang on with 3 shims, the right was close enough with 3 shims also.



Cheers!

-Kav.

[bob joyce]

thanks for making these great video's… The straight edge.... I am concerned about how well it is made... what do you get if you flip the straight edge over and check dimensions.... Hopefully it is exactly the same.... Maybe my concerns are miss placed ?... Please keep up the great work...

[Varmays]

Hey Kav,

still inspiring videos...

Thanks a lot!

[kav]

thanks for making these great video's… The straight edge.... I am concerned about how well it is made... what do you get if you flip the straight edge over and check dimensions.... Hopefully it is exactly the same.... Maybe my concerns are miss placed ?... Please keep up the great work...

I think that's a really good point Bob! You can't guarantee the quality of any tool these days I feel. I bought a new straight edge just for this task and I did check it against my old rule and my 4ft level to make sure it wasn't way out of whack so hopefully I'm good! I like your simple solution of flipping it over and measuring again, I will know for the next time! (wait there's a next time??!!)

Cheers.

-Kav.