Stihl 064 with 066BB, along with a complete rebuild of the bottom end

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That decomp plug is the one I pulled off my 088, but I believe they are the same as the 066.

I have a mahle 066 cylinder.......I am gonna go over the BB kit with a fine toothed comb and see what I want to do before grinding on it.
 
The plug I put in Stihlkid's stuck through like that too. Perhaps the head isn't as thick as stock.

Just ducked home to pick up a doc so did a quick and dirty check of the thickness of the head. Both BB Kits are 6 spark plug threads thick, Mahle is 5 threads thick. Also I withdraw what I said about the new kit having "significantly fewer comb chamber marks". That's come about because my eyes are crap - using a head mounted magnified it looks like the old and new comb chamb marks are the same - sorry - no time for phots.
 
Ok, a little boring update. I will post some pictures of it tomorrow when my dad and I go about putting in the new bearings and seals.

I grinded on the case to fit the BB piston skirts. I used a base gasket as my template.

Tapped the bolt holes out to 6mm x 1, now the 066 cylinder bolts fit. Brad mentioned in his thread that some of the bolt holes were blind. On my case, I didn't find any blind holes and was able to tap them all the way through and didn't have to cut off the cutter part on the tap. All bolts go down far enough.

Fixed the bolt hole near the serial number. It was chipped out and I put in a metal shim and then fitted some JB weld and fiberglass to secure it up.

Took a look at the BB kit again. Can't see anything obviously wrong. So I am gonna give it a go and hope for the best. If everything goes together smooth, I should have all together in the next few days and out with a tree crew next week for real field testing.

Pictures tomorrow!!!
 
Looks to me like the de-comp fitting is way to far into the cylinder. Lake is right, if this is an example of the QA at that plant it says a lot to the fact that this stuff is not ready for prime time. Casting flaws, slack machining tolerances, rings that hang in the ports, heavy wristpins, sketchy circlips, etc. The squish thing is poor. It is bone simple to hold .005" in a machining operatation. Set the spec at .025 +.003/-.002, not that hard. I could see maybe trying to make one these things work on a beater that is on its last legs, but there is no way on this green earth that I would install this stuff on my 660, especially as a "hop-up"!

If you think this QA is bad, you should have seen the run of late '97/early '98 Mahle 046 cylinders. Those were hands down the worst cylinders I've ever seen anywhere. Misaligned castings, irregular/asymmetrical ports, spark plug hole distortions- the whole nine yards. And these were Mahle cylinders on brand new units. There was also a run of Mahle cylinders on the early 440 that had a lip cast in the bottom of the lower transfers that puddled fuel and caused the saw to die after idling for a bit. Stihl had us pull all the cylinders off and grind that lip off by hand. Stihl only reimbursed us an hour labor on each unit we did. :censored:
 
Looks to me like the de-comp fitting is way to far into the cylinder. Lake is right, if this is an example of the QA at that plant it says a lot to the fact that this stuff is not ready for prime time. Casting flaws, slack machining tolerances, rings that hang in the ports, heavy wristpins, sketchy circlips, etc. The squish thing is poor. It is bone simple to hold .005" in a machining operatation. Set the spec at .025 +.003/-.002, not that hard. I could see maybe trying to make one these things work on a beater that is on its last legs, but there is no way on this green earth that I would install this stuff on my 660, especially as a "hop-up"!

Easy, Tzed..... the only known serious problem at the moment is with rings hanging in the ports, and only on a recent batch that had unconventional rings.

Unless the de-comp is hitting the piston, it's not a deal breaker. Have we heard a single report of a piston being damaged by a protruding de-comp valve on a BB kit ?

The circlips that came with my BB kit were conventional Stihl type, no complaints there.

Squish depends not only on the cylinder but also the case, the crank, the piston, and if the piston rocks in the bore. Squish on my BB kit/064 setup was fine, as I posted on a previous thread. A few thou difference could be due to measurement error, and even if it is real, it wouldn't be a huge issue if installed with a conventional 0.025" squish. Did anyone measure the the supposedly bad squish band with a precision depth gage, measuring between the base of the cylinder and the squish band ?

On my BB kit, casting quality was far superior to some of the Golf pistons I have seen. Casting quality inside the ports was identical to the 064's OEM cylinder -- no better or worse. So there's a faint part line on the casting -- big deal.

Does a BMW have better QC than a Hyundai ? Probably, but I can't afford a BMW. I can't even afford a Hyundai.:dizzy:

Thanks for the detailed report, epicklein22. Keep it coming.
 
Does a BMW have better QC than a Hyundai ?

Hyundai isn't made in China, and I bet the QC is way closer on the Hyundai to BMW that you think!

Bottom line, there IS no QC on this after market stuff!
 
Alright, update time. Today didn't quite go as well as the other, but the deed is done and the case is buttoned back up.

First some pictures of what I grinded on yesterday, so the BB piston will fit. Look closely and you can see where the crank was rubbing before when the bearing was letting go.

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Here is the clutch side bearing. My dad and I froze the bearings and then heated the steel insert with a propane torch. I know, I know, maybe not the proper way but it went in well. A little spit test showed that the steel insert was hot enough and a socket pushed it inward toward the case. Then I installed the oiler and pushed it back out to that.

]
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Flywheel side went the same way, except no oiler part. Just push till it seats on the innards.


Now to putting in the crank and assembling the case. Now I tried to follow the instructions of Lakeside about the clutch spider and a tube, but it wasn't working for me. It kept spinning the crank, not bringing it through the crank. Tried some other methods and nothing was working. So a little tapping gave me enough movement so I could start the bolts. Then I slowly tightened everything up using the bolts. I highly recommend buying some longer bolts and use those to put the cases back together. It went together so smooth once the bolts started and I didn't have to worry about messing up the bearings. A small tap to center the crank and everything was turning super buttery.

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Then the fun started. Flywheel side seal went in well. Then the clutch side. A tap on the socket showed we needed a little more and it was good to go. A couple taps and it is in too far!!! ####!! So we had to rip out the stihl seal and put in the Baileys seal. I think a good idea to put in the clutch seal would be to use the oiler to press it in. That is what I did with the Baileys seal and it seemed to work well. The case is fully ready to go. Not as easily turning as I would like, but I contribute that to the new seals. Nothing is touching or rubbing. If this isn't normal, tell me now.

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Started to put a little bit of it together and found out my oiler is junk. It will not loosen up and the pump looks to be bad. So now I need a oiler before it hits wood.
 
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Looking good. If the crank was nice and easy to turn before the seals went in, you're good to go. It is surprising how much resistance the seals create, relatively speaking. I assume you lubed the seals and bearings?
 
Looking good. If the crank was nice and easy to turn before the seals went in, you're good to go. It is surprising how much resistance the seals create, relatively speaking. I assume you lubed the seals and bearings?

Good deal. I greased the seals and oiled the bearings.

Tomorrow, I will slot the cylinder. Brad, how much did you bring each hole inward?
 
You might be able to get your oiler working simply by taking it apart and cleaning it with aerosol carb cleaner followed by some PB blaster or equivalent. I've saved many an oiler that was 'froze up'.

The only way to keep from pushing those PTO side seals in too far is to just be very careful. I've only ruined one in about the 700 cases or so I've assembled. All it takes is one.

Looking good so far. Remember that the holes on the Bailey's cylinder aren't necessarily the same as an OEM cylinder so your slotting operation will have to be touch and go.
 
You might be able to get your oiler working simply by taking it apart and cleaning it with aerosol carb cleaner followed by some PB blaster or equivalent. I've saved many an oiler that was 'froze up'.

The only way to keep from pushing those PTO side seals in too far is to just be very careful. I've only ruined one in about the 700 cases or so I've assembled. All it takes is one.

Looking good so far. Remember that the holes on the Bailey's cylinder aren't necessarily the same as an OEM cylinder so your slotting operation will have to be touch and go.

The oiler is junk. I already took it apart and tired to clean it up. I put the rod back in and still too hard. I assume the actual pump part is frozen.

Ya, it sucked fitting that seal in too far. Dad just got a little too cared away when he tapped on it.:cry: I did the Baileys one and tried to be super cautious. I hope that Baileys seal holds up. Quality sucks compared to the stihl one.

Ya, I will be going slow on the cylinder holes. You think a chainsaw file will get the job done?

Also, I plan on polishing up the exhaust. I know some say that polishing does little for performance, but it can't hurt and people have been doing it for years on all engines. No true port work, just knocking the casting flash off and then polishing it up real nice. Will I have to rebevel the port lips to the cylinder?
 
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No beveling will be required unless there wasn't enough to begin with. Were you able to get the adjustment screw and pump plunger out of the oiler housing? It's a pretty simple pump really and rarely ever wears out (unless it was pumping used automotive motor oil its whole life.)

A chainsaw file will work fine but it will be slow. I use a 1/4" carbide deburring bit in my Makita cordless for slotting mounts.

The polishing will help with carbon build-up, that's the gain there.
 
No beveling will be required unless there wasn't enough to begin with. Were you able to get the adjustment screw and pump plunger out of the oiler housing? It's a pretty simple pump really and rarely ever wears out (unless it was pumping used automotive motor oil its whole life.)

A chainsaw file will work fine but it will be slow. I use a 1/4" carbide deburring bit in my Makita cordless for slotting mounts.

The polishing will help with carbon build-up, that's the gain there.

Good info, the beveling from the factory looks good.

The oiler is toast. This oiler came off my 066 parts saw. The entire saw has seen a lot of corrosion while sitting. I don't know what was used for oil either, but I don't think it was bar oil. Seems like ATF. I will either have to find one locally, on ebay or here. I am gonna put the saw together anyways and sees how it runs, just no cutting yet.
 
Nice work so far! Since you were less than thrilled with Bailey's seal and you need a pump anyway, why not get another Stihl seal? Do it right the first time and you won't be doubting it later.

Chain files work pretty quickly on aluminum, but clog up quickly as well.

:popcorn::popcorn::popcorn:
 
While on oils seals.. the FW side of the 064 needs special attention. There are two different noses on the FW - one protrudes deeper than the other and can press into the seal. If set wrong, you won't notice as the "long nose" FW actualy pushes the seal in deeper, but it continues to rub, and fails in a short time. if you set the seal too deep, it will rub on the bearing.


There's a tech note on this - I'll try to dig it up.
 
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