McCulloch Chain Saws

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You & me both Ron.I've always heard that patience is a virtue.What the hell is a virtue?Lol

From what I gather from your posts, you have your moments but pretty much you seem to have come to terms with the idiosyncrasies of McCullochs.

If it weren't for Brian's interventions, there would be parts and pieces of old McCullochs flung all over my yard and in the woods - as well as more than a few John Deere items. I got plenty enough of each scattered already from the stuff that just falls off never to be seen again.

Ron
 
I noticed that all I have here is the older style AF brackets on all the 310s & the one 320 I have.I foundf out that we cannot order just the washers,choke plate,or AF bracket separately,they must be ordered as a "kit".Since I ordered a new AF bracket "kit" from Bob I'll have to give him a call to see which one I'll get.

As far as the order in which the washers go in the AF bracket,I can't tell by looking at the saw you sent back.My eyes are good for squat.I had my son help me the other day & we were still unsuccessful.

Think of it this way (I don't have any good illustrations to help...), the washers/spacers go under each end of the bracket to create some space for the choke plate to pivot. The plate pivots on the lower washer, and the spring washer goes between the bracket and the choke plate to keep it pressed against the airbox to achieve the choke function. You must have the correct washer/spacer for the choke plate to be able to pivot.

Mark
 
Hello all does anyone know where I can get the thick rings for 85239 7-10A piston? Or should I just order a piston and rings from the Lil Red building?
 
Hello all does anyone know where I can get the thick rings for 85239 7-10A piston? Or should I just order a piston and rings from the Lil Red building?
Do not,under any circumstances order any piston kits from Lil Red Barn.They cause complete engine failure.The wrist pin bearings are garbage.Try Bob Johnson at 607-638-9297,he should have what you need.
 
Ira - do you still have my address?

big10 - You have to be very careful using McCulloch published data, it is often filled with assorted errors. For example

1641181434436.png

I am pretty sure that 85239 is actually a thin ring piston and uses 89732 rings.

I believe the correct part number for the thick ring piston is 69412; 87166, 85241, and 63290 are all thick ring part numbers for the 2" bore.

1641181850715.png

The more you learn about McCulloch saws the less you know for sure about McCulloch saws.

What 67L36 is trying to say is the LRB pistons have problems of their own. Some don't have the ring grooves cut deep enough and the rings don't fit so you can't actually fit the piston and rings in the bore. In almost every case the wrist pins supplied with the LRB pistons are undersized and slide through the connecting rod instead of being a press fit as McCulloch intended. If you must use the LRB piston be sure to reuse your original wrist pin, or find a new one if you can.

Mark
 
From what I gather from your posts, you have your moments but pretty much you seem to have come to terms with the idiosyncrasies of McCullochs.

If it weren't for Brian's interventions, there would be parts and pieces of old McCullochs flung all over my yard and in the woods - as well as more than a few John Deere items. I got plenty enough of each scattered already from the stuff that just falls off never to be seen again.

Ron
Idiosyncrasies,now that's a polite way of saying they're a PITA,Lol If it weren't for the cost of tools & saws,I'd be throwing tools & beating saws to a powder with a hammer.I know my neighbors pray for the winter because I don't work outside & it gives them a break from my cussing,Lol.I have come a long way in the 4 short yrs.I've been working on these bumble bees.
 
Which piston/rings did you end up using in that one if you recall?

I know my favorite 7-10 has thick rings but I don't remember the details on the piston. That was a long time ago and I didn't take any photos of the internals when it was apart.

I am pretty sure this photo shows the two piston options, 85239 on the left and 69412/84240 on the right.

IMG_0174 (640x480).jpg

Mark
 
Thanks Mark you have a lot of knowledge about Mcculloch’s
This is my thick ring skittles piston and some pics of inside bore are these normal transfers for a 7-10A?
 

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big10 - those rings might work, but the locating pin in the OEM piston is different and the OEM rings have square ends. Additionally, the earlier ring sets (63290) had a chrome ring for the top groove. Later rings sets were both plain as the photo above illustrates. I think the chrome top rings were intended for the saws with a cast iron bore and the later plain ones could be used on either iron or chrome plated bores.

20220103_120608.jpg

Mark
 
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