Rob's Motor and Bus Build

[Clatter]

So we're going to build Rob a motor...

He's an FGI - he gets it.

Since the 'Cheap Junk' build in my sig is getting a bit old,
And Rob here isn't interested in Cheap Junk,
Follow along as we build one that's a bit nicer,
But still not super over-the-top,
Using what we have available today (2023).

Rob's bus is an earlier type 4 - 1.7.
Means it has the desirable '72-74 heat exchangers,
As well as the early 8mm valve adjusters.
We'll be sourcing a 2.0 lower end for the added displacement,
And build a 'best of both worlds' motor by mixing/matching parts.

Here's a decent-looking ED-code core case from a 1.8 bus.

My local hero/VW machinist Jim Musich measured it all out for me.
It had no spread center main, so good to go.
Main line bore tunnel was a bit pounded out, a couple thou, so it got a first line-bore at .020.

This guy is a real craftsman.
Shoulda cleaned up the oil/chips before taking the pic to do justice.
He runs a set of cutters at .015,
Then another set at .020,
Just because the hard aluminum type 4 cases tend to chatter and chew on a hard pass.
There's then a third cleanup pass with that same .020 cutter,
Just to give it that beautiful finish.
A nice finish is helpful here to ensure that no oil escapes around the OD of the main bearings.

When decking a case,
Jim will watch carefully how many thou it takes to clean up the face of a cylinder register,
And also how many thousandths it takes to clean up.
This one needed a bit more - like .010.
This is a bit on the high side, at least compared to the ideal.
Bus cases tend to run these numbers from having lived a hard hot life.
While 914 cases tend to usually clean up with smaller numbers,
They almost always touch off at the center main, from the revs that 914s might have gotten,
Indicating a slightly spread center main.
Bus cases might touch off in different spots, such as with this one,
Showing that it had been hot in its existence this last 50 years or so.

Last few cases have been this way.
Rob might strip down his original 1.7 and send it to me to take to Jim,
But that's no guarantee the registers will clean up in just a few thou.

Such as it is building a bus motor in 2023.

We're really happy to see these nice clean case registers.
They might have taken a few more thou to clean up,
But it was just some heat warpage and age/use, not a spread center main from too many revs.
They'll also be fully vetted once we move on to measuring and mock-up.

We'll end this here so it doesn't go 'poof'.
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Bus Motor Build

What’s That Noise?!?

[Clatter]

Digging thru my stash of cranks,
There's no 2.0 71mm cranks in good shape.
All i have now need turned.
Welcome once again to 2023!

Off to Ed's in Newark.

Support your local crankshaft grinder, people.
Cranks big and small.

Came back right at the top of spec on the mains,
But a few tenths over on the rods, unfortunately.

This might be a feature, depending upon how the rods and bearings end up,
As bearings tend to run big these days.
Only after measuring the actual parts will we know for sure.

Since this crank is going to Schroeder's in Seaside for a spin-balance job,
We might have Robert there polish a few tenths off the rod journals if needed.
Such is building motors.

Additionally,
Took a set of rods up to Jim that he rejected.
Because one was from a different set,
It was 15g lighter than the other three.
Another hazard of building in 2023!

Found a really grimy set in my stash, and they were all similar weights,
And had similar markings,
So good cores.
They'll get the big end re-sized and new pin bushings on Jim's Sunnen rod machine.

A volume 'engine house' rebuilder might have torn cores apart and thrown rods in a pile,
That's how we likely ended up with a mismatched set.
Just another thing to watch out for..

As for 228 flywheels, I like the waterboxer variety.
They have these oval windows.
Some were saying they're forged, but that apparently isn't true.

Note the socket head triple-square mounting hardware.
(had them cad plated )
These are smaller than the bus flywheel bolts because the Vanagon flywheel has more reinforcing meat by the mount flange.

And i always grab a good used German Sachs pressure plate when i see one.
Just because..
If the shoe isn't scored, why not?
The do balance nicely compared to Brazilian.

Once bearings and rebuilt rods show up,
We'll be able to get this bottom end off to balance.

Anyhow, there's a start.
More to come...
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Bus Motor Build

What’s That Noise?!?

[Ceckert64]

I'm interested to see another build, I'm about to get back into my Type 4 rebuilds in a month
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1964 sunroof Beetle Restoration "Herbie"
“Joann” 1970 Elm Green Squareback
1972 Sierra Yellow Tin Top Westfalia Camper
“Fitz” 1971 Westfalia Poptop

[Cdn17Sport6MT]

[Cdn17Sport6MT]

@Clatter, re the potential for a cracked case where the oil strainer retaining bolt goes... obviously you checked for that. Does it merit dye penetrant checking, or another testing method? If u find a prb is the case scrap? Can it be repaired?

[Clatter]

Good questions.

Pressure plates live in a very dusty/dirty environment trapped in the bellhousing with all that clutch material.
Not a lot you can do about it.
A shoe will get scarred up before the fingers of the diaphragm give trouble.
Seen people that should know soda blast them,
But not sure that’s a good practice.

A re-nitride would be nice to do,
But this isn’t an airplane engine
(Even though it looks like it ).
Perhaps the rod bearings and journals might get scuffed and worn sooner on a re-grind,
But I’m of the opinion that keeping head temps down can do far more to save everything in the motor than anything else you do.
Good oil and frequent changes help,
As do valve adjustment being right.
If you keep the heads and oil from overheating,
These motors can last a long time, even a lifetime.

So very many things conspire to overheat.
Intake leaks/lean running, poor timing control, exhaust leaks…
These are all real problems you’ll find on most of these buses running around right now.
If you have the temps under control,
Lots of cool clean oil will help everything live,
Even rod journals with some of the hard nitriding ground away.

FWIW,
This crank is 1St under, like any ground type 4 I’ve seen.
Most all type 1 cranks are getting a 2nd or 3rd grind now.
Most don’t seem too concerned about journal life.
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Bus Motor Build

What’s That Noise?!?

[Clatter]

WRT “the syndrome”,
A case will either be cracked at the sump plate or it won’t.

If you can find a welder and machinist to fix it,
It’s not really that hard to do.
These aluminum cases seem to weld more easily than the mag type 1.

Fortunately, i’ve been collecting cases for a long time,
And had good luck,
So any with a cracked sump plate bolt area just get tossed.

Maybe one day I’ll regret that, eh?
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Bus Motor Build

What’s That Noise?!?

[Clatter]

[Cdn17Sport6MT]

Thx @Clatter.

I'll be particularly interested in your discussions re cyl heads... cracks (inspection), interference-fit of the the seats, potential broaching of the valve guide bores. Cc'ing the heads, deck ht. Also interested in how valve guides can be drilled-out to 90% with a piloted bit, then drifted-out...😊

[Clatter]

So, you guys all know what an FGI is, right?

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Bus Motor Build

What’s That Noise?!?

[Clatter]

[Cdn17Sport6MT]

Getting ahead of myself... but my heads only have 40,000 miles on them, all but 11,000 under my use and care... Otherwise, Len Hoffman, HAM, AMC castings, then he starts from scratch? $$$

[Cdn17Sport6MT]

What's an FGI?

[Clatter]

[Clatter]

Here’s a tidbit..

Was up at Jim’s yesterday.
He’s got this nice looking single-port head in the trash.

Single-ports are getting rare.
Blasted clean.
Exhaust guides out.
Valve job is started.
No cracks anywhere.
Plug threads good.
Studs all in good shape.

I’m just an emotional woman,
Can’t resist my love for these things,
And took it home!

Luckily, rational thought finally won,
And it went into the trash here at the house.

Who can guess why?
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Bus Motor Build

What’s That Noise?!?

[SGKent]

This is long, get your coffee.

Steve - your choice of machinists is outstanding. I don't know them but can tell from the attention to detail that they are good old school shops. Word to the wise on the big end on the rods. I say this because I have seen some very good shops make this mistake depending who did the work.

When rods are resized, they get cleaned in the glass bead machine, and inspected. a little (.001" - .002") is clipped (ground) off the cap and preferably rod side too with the bolts out. Then the bolts are put back in, using a raw hide or some use a lead hammer.

Next the two halves are clamped together, and torqued to spec. Then off to the Sunnen.

On the Sunnen machine there is a gauge that gets set up to measure the inside of the big end. When that rod is sized, it should be turned 360 degrees on that gauge to be sure that it is not pinched at the part line. The problem is that human wrists and hands don't rotate 360 degrees so many people only get maybe 280 - 320 degrees on the gauge. However if the cap is slightly offset, it can be PERFECT for those 280 - 320 degrees and still be pinched .002" or more right at the cap. One side of the part line will be wider and one narrower. It is the narrower side that will bite one's butt later and cut the life of the engine, sometimes even cause excessive wear, or at high rpm seize.

The easiest way to be sure that the machinist has measured 360 degrees is to look at the small lines the measuring point on the gauge leaves on the surface of the rod. It is hard to see but if one looks closely they can see the scribe lines on the surface. Make sure those lines go 360 degrees around. If not have them put back on the measuring gauge to be sure that the rod is correctly sized all 360 degrees. One really has to wind their wrist and arm up to do the full 360.

The other issue is the speed at which the rod is resized. If an old timer, or automatic system is doing it then it will be fine. But if someone newer is at it manually, they may not have the rhythm to honing down. There needs to be a short pause at each end of the stroke, to keep the stones and the rod even. As the stones pass over the rod, the center of the rod gets 2X as many passes as the outside edges. That will make it bell/hourglass shaped as well as wear the stones funny. It will look nice and shiny but not be an ideal surface for the bearing to sit on.

Colin was here and I explained the same to him. He, as many had trouble getting his head around how the inside gets 2X as many passes.

Three people stand in a row. Someone hands them each a dollar. Person 1 gets 1, Person 2 gets 1, Person 3 gets one. All are even. Now the money gets handed to person 2 again, then person 1, At this point, Person 1 and 2 have 2 dollars each but person 3 only has 1. Now person 2 gets a dollar again, and then person 3. Now in the count, person 1 has 2 dollars, Person 2 had three dollars, and Person 3 has 2 dollars. Then Person 2 gets another dollar as the money starts the other way again. At this point Person 1 has 2 dollars, Person 2 has 4 dollars, and the 3rd person has only 2 dollars. If this pattern continues in the rod honing, the middle gets worn out 2X as fast as the outside. So the person honing has to pause at each end to even it up - same as passing out money like 1 - 2 - 3 - 3 - 2 - 1 - 1 - 2 -3 -3 -2 -1 to keep it even rather than 1 - 2 - 3 -2 - 1- 2 - 3 - 2 -1 -2 - 3 etc.

I share this because I have seen many rods that are much less then properly done, and it is a common point machine shops fail at unless the person doing the work is really focused and trained at it. Typically rod sizing does not go to the most senior person in the shop, and not all the people in a shop are as industrious as the Master is. That said, someone who is focused can give you a set of connecting rods back that are far better than even when they left the factory. A good set of balanced rods, good bearings, and a well ground crankshaft will last a very long time without problems.
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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

[Clatter]

Excellent detail about rods, Steve.

The skill of using these specialized machines properly is far more valuable than the machines themselves.
While there might be lots of Sunnen rod hones around
(Jim had two)
Skilled operators of these are very rare indeed.

Even more, anyone with limited experience should be doing it regularly to stay in practice.

Only a seasoned master can jump on something like a rod hone and knock out a set of rods correctly,
Without a couple practice passes or doing something wrong.

Jim's an FGI.
He fucking gets it.
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Bus Motor Build

What’s That Noise?!?

[Clatter]

[busdaddy]

Cut crooked?
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[SGKent]

(1) value guide issue. Finding guides the right over-size to fit the guide bosses? (2) Also a crack running under one of the seats. Too much work for the value of the head.

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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