McCulloch Chain Saws

[67L36Driver]

This 250 IPL is dated Aug. '65.

The check is at the bar mount behind a little plate secured by a small screw.

I need to pull the top off the tank as I can't see the pick up line.

Meanwhile, I put a more 'small geezer' friendly bar/chain on him. .404 x 20

I found I have the high side way rich.

 

[Warped5]

Super 550 finally a runner!

Finally took the Super 550 off the shelf at Aaron's behest ...

Here's a 'before' shot right when I got it about 3 years ago ..



Replaced the flatback with an HL-63E out of the parts stash. Put a kit in it while I was at it. I do think the thread that Promac posted about 'priming' these carbs during re-assembly did help. Cleaned it up pretty good. Also put in a new A/F, plug, rear rubber grip and spike. Never have seen a spike in that style before. Will be getting a chain shortened for it tomorrow or Saturday.

Saw runs real well, but there's a lot of oil in the crankcase .... smokes pretty good at times.

 

[rwoods]

Joey, any idea why the compression is so high? I think 175 to 185 psi seems to be the norm advertized for a good condition SP or PM850. Ron

 

[joeymt33]

Joey, any idea why the compression is so high? I think 175 to 185 psi seems to be the norm advertized for a good condition SP or PM850. Ron

I even ran the saw a bit before taking this reading. I have no idea why it's that high. Maybe my gauge is off by 20 or so. I need another gauge to compare it to. I've never doubted the gauge though, never had a reason to.

I guess it's possible that I put a "C" piston in a "B" cylinder or something similar. I've never intentionally done that and I don't think I did in this case but who knows. I'm not sure that it would even work.

 

[minosi]

Joey...I have a SP80 with 190-195, FYI.

I have the same tester as yours too.



-Andy

 

[heimannm]

Ted - looks to me like it started life with plans to be a normal 5 tooth spike but took a second hit in the presses. Wonder why no one noticed and pulled it out?

Mark

 

[minosi]

Gents-

Got started on the 790, couldn't wait to find out what was going on in the crank case.

I may restore the old girl someday, but for now she'll remain "rough".


Anyways....


I have see a lot, as I am sure many of you have...but this is a little extreme:

View attachment 299057


Now, it did have a oil cap on it when I got it...apparently that was a "option" when the saw was "stored" at some point!


Hey, for $25.00 what should I expect right?


Ah yes, back to the internals...this is a little extreme as well, to say the least:

View attachment 299058


I have gotten extremely lucky as this saw probably ran for a second before shut down...


Looks good:

View attachment 299059


Here too, exhaust side:

View attachment 299060


Intake side:

View attachment 299061


Now, I have measured the crank, the rod and cap, the piston and the cylinder...nothing appears to be out of round, or significantly worn...by some miracle.


Given the coin I have spent on the 797, I'm going for it...new seals and needle bearings (and a Tilly switch) and fingers crossed!


-Andy

 

[67L36Driver]

Oiler ball check is located behind the little plate w/hole.

Replaced the rather wimpy spring with one from a Homelite C5. (They have two, one at the pump and one at the bar mount.) Now we get more positive output.


The Windsor UXL may not be just the right bar mout pattern.

 

[Warped5]

Ted - looks to me like it stated life with plans to be a normal 5 tooth spike but took a second hit in the presses. Wonder why no one noticed and pulled it out?

Mark

Hi Mark - IIRC, I ordered about 4 spikes and it was just in with the bunch. Kind of a unique look, though.

 

[leeha]

Gents-

Got started on the 790, couldn't wait to find out what was going on in the crank case.

I may restore the old girl someday, but for now she'll remain "rough".


Anyways....


I have see a lot, as I am sure many of you have...but this is a little extreme:


View attachment 299057


Now, it did have a oil cap on it when I got it...apparently that was a "option" when the saw was "stored" at some point!


Hey, for $25.00 what should I expect right?


Ah yes, back to the internals...this is a little extreme as well, to say the least:


View attachment 299058


I have gotten extremely lucky as this saw probably ran for a second before shut down...


Looks good:


View attachment 299059


Here too, exhaust side:


View attachment 299060


Intake side:


View attachment 299061


Now, I have measured the crank, the rod and cap, the piston and the cylinder...nothing appears to be out of round, or significantly worn...by some miracle.


Given the coin I have spent on the 797, I'm going for it...new seals and needle bearings (and a Tilly switch) and fingers crossed!


-Andy

Wow, Did those bearings come from the wrist pin or lower rod.
If they got that hot i can't imagine there is no other damage.




Lee

 

[leeha]

Ted, I have a couple new dogs just like yours. Can't remember
what models they were for. For some reason i'm thinking like
the D44 style saws.




Lee

 

[minosi]

Wow, Did those bearings come from the wrist pin or lower rod.
If they got that hot i can't imagine there is no other damage.

Lee

I hear ya Lee, but what you see is the way it is...I am somewhat amazed.

They are from the crank end, the cap was just a little loose, one bolt more than the other.

The crank is not out of round, nor is the rod.

A small piece made it to the combustion chamber...the piston top is in good shape, with 5 or 6 tiny dings...nothing that concerns me.

Ideally, I would go ahead and re-bore with a new piston/rod, I'm just curious how she'll run, the old war horse.

Should know more in a few hours...too wet to work = saw time

-Andy

 

[Warped5]

PM800 .. Day 1

I got the powerhead for cheap at an OPE shop nearby. The 16 year old service tag on it said 'Trashed.' Had been robbed for small parts and bits over the years. Tested compression .... 40 PSI. Did the teardown today to see why and I guess my question's answered.

Notice how the lower ring kinda blends into the piston at one point:



So I went about cleaning the cylinder (2nd one ever for me). Initial inspection revealed very little aluminum transfer and there wasn't much bubbling going on once the acid was applied. Here's a couple of shots of the cyclinder:





Can some of the more experienced eyes here give me an idea of how well the cleaning went?

Thanks!

 

[ozflea]

I got the powerhead for cheap at an OPE shop nearby. The 16 year old service tag on it said 'Trashed.' Had been robbed for small parts and bits over the years. Tested compression .... 40 PSI. Did the teardown today to see why and I guess my question's answered.

Notice how the lower ring kinda blends into the piston at one point:



So I went about cleaning the cylinder (2nd one ever for me). Initial inspection revealed very little aluminum transfer and there wasn't much bubbling going on once the acid was applied. Here's a couple of shots of the cyclinder:





Can some of the more experienced eyes here give me an idea of how well the cleaning went?

Thanks!

Looks all Dandy to me

McBob.

 

[joeymt33]

I got the powerhead for cheap at an OPE shop nearby. The 16 year old service tag on it said 'Trashed.' Had been robbed for small parts and bits over the years. Tested compression .... 40 PSI. Did the teardown today to see why and I guess my question's answered.

Notice how the lower ring kinda blends into the piston at one point:



So I went about cleaning the cylinder (2nd one ever for me). Initial inspection revealed very little aluminum transfer and there wasn't much bubbling going on once the acid was applied. Here's a couple of shots of the cyclinder:





Can some of the more experienced eyes here give me an idea of how well the cleaning went?

Thanks!

Looks terrible! You should trash it like the tag said. A better idea is, send it to me and I'll take care it.

 

[67L36Driver]

Looks all Dandy to me

McBob.

+1

Looks terrible! You should trash it like the tag said. A better idea is, send it to me and I'll take care it.

Don't listen to him. Darn vultures................................................................:msp_rolleyes:

 

[Macman125]

I got the powerhead for cheap at an OPE shop nearby. The 16 year old service tag on it said 'Trashed.' Had been robbed for small parts and bits over the years. Tested compression .... 40 PSI. Did the teardown today to see why and I guess my question's answered.

Notice how the lower ring kinda blends into the piston at one point:



So I went about cleaning the cylinder (2nd one ever for me). Initial inspection revealed very little aluminum transfer and there wasn't much bubbling going on once the acid was applied. Here's a couple of shots of the cyclinder:





Can some of the more experienced eyes here give me an idea of how well the cleaning went?

Thanks!

Looks good buddy.

 

[rwoods]

I must be coming down with something …

After several hours of mowing today, I had my choice of cutting up a 2 foot oak that fell within feet of my wood pile or working on the PM800 with the streaked piston. Any other day it would be cutting hands down, but not today – don’t know why other than the lab is 15 degrees cooler than outdoors. Long story short, I may never buy another used saw with an unknown history. :msp_sad: Not only was the piston toast with big melted gouges, there was thick aluminum transfer, the flywheel had been replaced with the older 24 fin (cover scraped from the lack of clearance), every exterior screw and nut must have been put on with an impact driver, one of the flywheel pawls snapped off during removal of the flywheel, the rear AV mount was sheared into three pieces and the oiler flat spring clip was broken. I was a little :msp_angry: as the flywheel replacement was oblivously done recently as it was clean and everything else was covered with an average amount of sawdust and oil. I couldn't tell whether the rings had been replaced or someone had done a little creative scraping through the exhaust port; the muffler likely had been removed at one time as the washers were missing on two of the three bolts. The unexpected rebuilding of this saw is putting a serious dent in my NOS parts inventory and is helping turn my remaining project MACs into parts MACs. I hope it is a good runner when I get it back together. Ron

 

[heimannm]

I get maybe 1 or 2 decent saws out of 10 used saws that I buy, some of the rest can be made to run but few are really nice. Every so often I get a nice surprise, like the 805 that came out of some barn in Indiana, but most of the time a used saw is in fact a very used saw.

I won't stop trying however, since I still have more than a few holes in the collection line up.

Ron - If I ever get back to the US of A we can start the 800/8200 discussion again.

Not much to do in Singapore today, hopefully I will be home by next Saturday but I will be making a quick pass through Australia before then...

This is still the McCulloch thread, isn't it? How about this old photo from back when the collection was small?

Mark

 

[rwoods]

Just got back from the chainsaw lab, after cleaning the cylinder I decided to replace it - too far gone for me. Replaced the piston, rings and seals. Did the two back screws oiler fix again - not pretty freehanding it on the drill press but it will work. Also drilled the cylinder for a DSP port. Maybe tomorrow I'll get it reassembled. Bedtime now.

Mark, no fears - I'm leaving the PM8200 alone.

Ron