McCulloch Chain Saws

[Manic84]

The go-to is usually to lightly apply heat, like propane. But I'd be a bit careful with that.
I'd start with soaking it with a penetrating oil or some sort of solvent to try and loosen them up.

If they're just stuck from sitting too long, you might have good success with just the solvent route. That should wipe out whatever gunk is there. If that doesn't work, you'll have to go with heating it.

 

[vinnywv]

I agree mark. Soak in your favorite penetrating oil. If a no go try light heat.

 

[Maintenance supervisor]

I've had some luck with soaking them in brake fuild.
More than likely there's some carbon in grove adhering to the rings.

 

[ozziechainsaw]

Hi Guys,

I got a nice early Mac 10 RH start this week but it needs either a new rewind spring or something in the rewind assembly setup. I forgot to get a photo of the set up inside but it seem loose, like something is missing.

Also I have a 5-10 also that needs a new rewind assembly and they do look similar. Are they the same ?

Does anyone have a IPL and workshop manual to suit.

Justin

 

[rwoods]

More of a preventative measure possibly for those who store iron bore saws for long periods - at the auto salvage (junkyard) I worked at during my high school and college years, they poured ATF down the carbs of running engines before putting them on the shelf. I have never tried it on a two stroke.

Ron

 

[vinnywv]

Hi Guys,

I got a nice early Mac 10 RH start this week but it needs either a new rewind spring or something in the rewind assembly setup. I forgot to get a photo of the set up inside but it seem loose, like something is missing.

Also I have a 5-10 also that needs a new rewind assembly and they do look similar. Are they the same ?

Does anyone have a IPL and workshop manual to suit.

Justin

Yes they are the same starter. They will interchange on both saws. As for ipl, ask for an ipl on the "beg for manuals" thread. Youll have a answer in likely a few hrs if that. I just did the same for a cp55 mcculloch. It has the same starter also and asked for an ipl over there. Had it in less than 2 hrs.

 

[heimannm]

Now that the piston has dried out from the trip through the mineral spirits part washer it looks more like aluminum oxide (white residue) in the gaps and lands. This is a thin ring piston which is good news/bad news. Harder to work on getting the rings out, but I do have a spare set on hand if I can get these out.







I am starting out with the ultrasonic cleaner to see what happens. I only get to work on saws a little bit each day while Mrs. Heimann is still laid up so I will have some time to let the different treatments take effect. For what it's worth, the piston actually looks better in person that it appears in the photos. There are some light scratches but nothing that would keep this saw from running if I ever get that far.

Mark

 

[rarefish383]

Just torqued down the rod cap on the 7-10. Then I thought, maybe I was supposed to put a drop of loc tight on it. Should I pull the screws and put a drop on them. Don't want to have to pull it apart later. If so, which flavor?

 

[Syncop8r]

I wonder if an oil filter wrench might help dislodge those rings...?

 

[Woodslasher]

I wonder if an oil filter wrench might help dislodge those rings...?

Or some gentle taps with a small hammer?

 

[Syncop8r]

I got a nice early Mac 10 RH start this week but it needs either a new rewind spring or something in the rewind assembly setup. I forgot to get a photo of the set up inside but it seem loose, like something is missing.

This may or may not be of help:

 

[Woodslasher]

Hi Guys,

I got a nice early Mac 10 RH start this week but it needs either a new rewind spring or something in the rewind assembly setup. I forgot to get a photo of the set up inside but it seem loose, like something is missing.

Also I have a 5-10 also that needs a new rewind assembly and they do look similar. Are they the same ?

Does anyone have a IPL and workshop manual to suit.

Justin

I've torn apart one or two of those recoils, if you post up pics of what you have I'll try to help, plus I've got two saws with RH recoils I can look at/post up pics of their guts if that'd help.

 

[PogoInTheWoods]

I'd try a combination of penetrant of choice along with some heat on those rings. Depending on the USC and its heat range, a separate container with the penetrant and the piston could simply be put into the normal heated USC solution (if not just directly immersed if you have one of the smaller Harbor Freight cheapies). 50/50 ATF to acetone is a proven penetrating remedy for rust. Not sure how effective it would be in this situation.

 

[hseII]

Looking for advice on the best way to get rings unstuck. There is no galling or scoring, just appears to be a victim of setting for a long time.

View attachment 893095

View attachment 893096

View attachment 893097

Mark

Do you have any Kroil?

Kano Kroil Penetrating Oil, 8 ounce liquid https://www.amazon.com/dp/B000F09CF4/ref=cm_sw_r_cp_api_glt_fabc_E7BN1J5P49SRZKY9EVJX

Down the spark plug hole and keep adding till it starts running down the inside of the cylinder into a bucket.

Over the course of a couple days.


Sent from my iPhone using Tapatalk Pro

 

[rarefish383]

I'd try a combination of penetrant of choice along with some heat on those rings. Depending on the USC and its heat range, a separate container with the penetrant and the piston could simply be put into the normal heated USC solution (if not just directly immersed if you have one of the smaller Harbor Freight cheapies). 50/50 ATF to acetone is a proven penetrating remedy for rust. Not sure how effective it would be in this situation.

I'm with Pogo. My Homelite C72 was locked up tight, two weeks with ATF/Acetone soaking in the cylinder and it freed up. But, the rings were stuck in the grooves bad, almost no compression. Filled the cylinder again, pushed it to the back of the bench and forgot about it for at least a month. The rings freed up and I had compression enough that it fired on a prime with 3-4 pulls.

 

[northwest saws]

I'm with Pogo. My Homelite C72 was locked up tight, two weeks with ATF/Acetone soaking in the cylinder and it freed up. But, the rings were stuck in the grooves bad, almost no compression. Filled the cylinder again, pushed it to the back of the bench and forgot about it for at least a month. The rings freed up and I had compression enough that it fired on a prime with 3-4 pulls.

I had one like that from a 1-51 a month ago. Piston and rings were super gunked up with crud, varnish and oxidation. I did something similar but with used motor oil from a diesel engine. I think I let it sit for a week or so and that did the trick. I used my little stihl clutch spring tool for the really stuck piece of ring left afterwards.

 

[heimannm]

The USC did a nice job of getting everything clean, but the rings are still stuck tight. If time and conditions allow tomorrow I will try alternately try heating and soaking in Sea Foam as that is what I have on hand. Maybe heating and USC with Sea Foam...

Mark

 

[mogulmasher]

Scored a bucket list Mac tonight. Got a 7-10 in a 3 saw deal. The other 2 are a 3200 and a Mini Mac 30. Probably send the other 2 down the road but excited about getting the 7-10 going. The good; its pretty clean, clean inside tank, fuel line looks good, pulls over smooth, working decomp valve, tons of compression. The bad; broken lower section of clutch cover and missing muffler cover.

 

[fossil]

Just torqued down the rod cap on the 7-10. Then I thought, maybe I was supposed to put a drop of loc tight on it. Should I pull the screws and put a drop on them. Don't want to have to pull it apart later. If so, which flavor?

From the 10 series manual. Item 5 (c) and (d)

 

[rarefish383]

From the 10 series manual. Item 5 (c) and (d)
View attachment 893362

Thanks Tim. I have that manual, should have read it better. I did notice that both of my rods and caps have a circles stamped on one side of them to mark the matching sides.