050 051 075 076 Info Thread

[PogoInTheWoods]

But I'd be loosing seal there ???

Yes. May need to modify the bushing to maintain the seal but to also give way to the needle cage..., as in getting rid of the outer length of bushing. Looks like you may need to find another clutch drum otherwise. Gotta be a way. It's been done before. @Rockfarmer has converted some chop saws back into chainsaws complete with drilling the case for the normal oiler (if I'm not mistaken). May want to search back through the thread or just Google it to see what may pop up.

 

[chilipeppermaniac]

If HS carb, it would be the HS-60.

OK I rechecked and the Tillotson made in Ohio is marked HS60B442 if my eyes are seeing right. The Stihl engraved Marvel Schebler Tillotson one says S 138B05

 

[PogoInTheWoods]

My 051 serial number. Raised cast lettering for the model info on my air filter cover instead of the metal tag. Early saw.

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[Farmerboy]

Ok, here’s a pic with bushing removed, then installed.

 

[chilipeppermaniac]

Thanks Poge, THOSE last 2 pics really paint the picture of what Farmer is trying to ask.
Hmm your o51 begins with a 3, What kinds of info does your serial tell you?

Interesting, what u say about the raised lettering too. I have one tagless 076 SUPER style one and one with the 075 AV Metal tag

 

[PogoInTheWoods]

The bushing needs to be machined to remove the sleeve in front of that narrow flange/washer piece to allow the needle cage (and clutch drum) to occupy the same space on the crankshaft. Another option may be to ditch the bushing altogether and use a worm gear for a conventional oiler in its place to simply make the seal and provide the seat for the needle cage and drum. A seal/spacer of sorts. Not sure the dimensions would be exactly correct, but it's worth investigation as an option.

About the only thing my serial tells me (without digging into the IPL's for references) is that the saw was made before 1981 when they introduced 8 digit numbers. LOL

Here's a tech note I dug up about serial numbers that explains how some of it is applied these days. Doesn't help much for older stuff aside from clarifying the use of their 'arrow' symbol.

Not aware of any 075 or 076 having the model designation cast into the filter cover like the early 050/051.

 

[PogoInTheWoods]

This is one style (pin type) of worm drive gear that should work in place of the bushing. There is also a drive plate that would normally be used as an interface between the gear and the clutch drum which holds the pin (or pins) that drive(s) the worm and ultimately the pump. It would also need to be used just for spacing and to keep the sprocket from riding up against the oil seal unless some other type of suitable thrust washer was used in its place.

Here's how it would normally be in a conventional configuration using the same bearing and oil seal as what is found in a TS510. The worm in the illustration is the later lug style instead of a pin drive but the arrangement and functionality of components is otherwise the same. A lug style worm could be used by simply grinding off the lugs. The type of drive washer (either pin or lug) is incidental in either case since an oil pump doesn't exit. What's pictured below should slide right into place on a chop saw being converted to a normal saw clutch with external oiler providing the crankshaft is a later 1111 030 1402 crank with corresponding bearing and seal. A worm from a very early 050/051 saw with a 1401 crank won't work as it has a smaller O.D. for a smaller seal and different bearing. The TS510 should have a 1402 as should 95% of donor saws that would be sources for the normal oiler drive setup as illustrated below including most of the 050/051 pin drive saws. The acceptable part numbers can be easily determined by the IPL's.




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[chilipeppermaniac]

Poge is truly an asset to this forum. NICE job brother Poge

Thinking about all it takes to convert a cutoff saw to a chain saw seems mind boggling to me. IN that vein, will Farmer still need to address bar plates, how they attach, and other various differences a chainsaw has that a cutoff one is missing and needs alterations for?

I have a hard enough time making the easy stuff work, let alone trying to modify a giraffe into a Llamma so to speak. I might try starting with a chainsaw that might need parts and then use a cutoff saw to make up all the similar ones and thus keep the modifications to a minimum. Just because I don;t have the skill or knowledge to not miss something in the conversion.

 

[chilipeppermaniac]

Not sure if this has been posted yet, but this fella does know saws.

 

[hiluxxulih]

I wanted to share a picture of my Dad's Stihl I believe it's an 075 , I just got running today after sitting since the 80s , it has interesting story , when my Dad worked for Weyerhaeuser on the Oregon coast they used to leave the saws on site overnight instead of bringing them in everyday , My Dad sat his saw beside a tree
( they were cutting old growth ) that night there was a wind storm and tree blew over and it was buried upside down a few feet for 2 years when we were finally able to locate it dig it up it started on the second pull .

 

[chilipeppermaniac]

Hi Poge, I still have not put my 075 or 051 back together yet. I have had many other issues to tackle but have been using my thinking cap while they sit.
One thing I think I need to make sure I attend to and address as a possible source of detrimental air leaks if the oiler seal(s). Just sitting on my table, the 075 crank case has soaked the paper grocery bag it sits on with oil as I await my decision to split the case or not.

In your experience, does this seem like it is critical that I need to disassemble the saw further and get into the oiler setup to install new seal. I got into redoing this saw due to low compression and obvious friction marks on the old Piston and Cylinder when I got the saw from the previous owner. To ensure no air/vacuum leaks will be present when I install the new crank seals, top end, exhaust, intake etc, my logic tells me YES, the oiler setup needs to be 100% in order to not get potentially damaging effects from air leaking at the oiler area. Also, this saw does have the Manual pump knob on the top of the saw if there is anything there I need to look for as well.

 

[PogoInTheWoods]

@Rockfarmer is the resident leak test expert but I do believe there is a potential for air leakage at the oil pump if it is not properly sealing. I think there's a way to test just the case and crank seals without the pump in place by somehow blocking off the oil pump cavity if you suspect the pump seals as a leak source. I may be thinking of another saw/situation, though. I also believe there's an 'O' ring behind a retaining carrier for the crank bearing on one side or the other that needs to be taken into consideration when doing an air leak check. Would need to dig into a manual to double check that. May only apply to a certain range of serial numbers like many specifics that changed over course of the series.

Do you have the 1111 shop manual?

 

[chilipeppermaniac]

NOPE to 1111 Shop manual. Pretty sure I know where to find PDF's of manuals. At least I can try looking at what I thought was them. And Thanks brother Pogo.

 

[PogoInTheWoods]

Here's a link to one too large to attach and another one attached below as two files. Should pretty much cover ya.

https://drive.google.com/file/d/0BxP5Bbk4lL0AWndmRDF3RGRMT00/view?usp=sharing

 

[Goinwheelin]

The amount of info in this thread is amazing. I haven’t read it in its entirety, just skimmed and searched for what I’ve needed so far. Anyways I picked up an 051AV about a month ago for next to nothing, rough cosmetics but everything is there. then a few weeks later I picked up what was advertised as an 051AV off eBay. Turns out after disassembly it’s an 075AV so I’m doing a full overhaul/ re finish. I’ve already stockpiled some NOS parts like the fan housing/recoil assy and inner fan housing. Clutch cover and exhaust cover. My question is what is the opinion around here about the aftermarket overhaul kits I see online? I see Cylinder, piston, crank, rod, bearings, seals, gaskets. Kits for around $220. I don’t plan on heavy/commercial use after I’m done, just something to break out and show off/conversation piece during cutting season.

Edit: the internals looked pretty good. piston had a slight scuff I couldn’t see until disassembled and the cylinder looks really good.

 

[Woodslasher]

I’m looking at picking up a “running” 075 for $200 in a few days, is there anything beyond the p/c condition I should check on? Here is the only pic I have of the saw. P.S. What is required to pull the muffler on this?

 

[Goinwheelin]

What is required to pull the muffler on this?

An Allen wrench. You’ll have to take the top cover off etc to get to it though.
https://www.motoculture-jean.fr/upload/pdf/075.pdf

 

[William Balaska]

It's already apart, look at the handle.

 

[Rockfarmer]

@Rockfarmer is the resident leak test expert but I do believe there is a potential for air leakage at the oil pump if it is not properly sealing. I think there's a way to test just the case and crank seals without the pump in place by somehow blocking off the oil pump cavity if you suspect the pump seals as a leak source. I may be thinking of another saw/situation, though. I also believe there's an 'O' ring behind a retaining carrier for the crank bearing on one side or the other that needs to be taken into consideration when doing an air leak check. Would need to dig into a manual to double check that. May only apply to a certain range of serial numbers like many specifics that changed over course of the series.

Do you have the 1111 shop manual?

Far from an expert,.. lol, but thanks! As far as a leak down/pressure test, i dont know of a way to do it without the pump in place. You can do it without the clutch though. put some washers on the clutch shaft to hold the worm in place with clutch nut to hold. I block off intake and exhaust with rubber sandwiched between carb, muffler, use clutch nut and then 7#s air pressure in thru the vacuum line. Take a paint brush and bar and chain oil, paint oil over all sealing surfaces and watch for bubbles and pressure drop. A slow leak isnt the end of the world but if it drops in seconds thats very bad and has to be fixed. The seal inside the worm is a bugger and often overlooked. also seen them leak at oil adjuster (2 o rings). The pressure test identifies the leak, the vacuum test confirms the repair.

 

[PogoInTheWoods]

The importance of a vacuum test can't be overstated even if a pressure test doesn't show any major issues..., especially at the crank seals. A bad oil seal will often seal with pressure and still leak under vacuum like a one way check valve. And finding that type of vacuum leak can be tricky since using pressure easily masks it. If using pressure to look for bubbles at a seal, just use very low pressure and soapy water. Apply just enough pressure to keep the soapy solution from entering the bearings/case, but not enough to close the leak. The other way is to use vacuum with oil or light grease at the seals to observe if the oil/grease is drawn in around the seal and/or the leak stops as observed on a pressure/vac gauge.