Mcculloch 610 oiler building to much pressure.

[hambone8978]

Hey guys I need help with my dads old 610. Awesome saw that has seen a ton of wood and won't die. I'm having trouble with the oiler building up pressure while running. It builds so much pressure that the manual oiler button gets stiff and you can't move it. With the saw not running you can pump the manual oiler and it works fine. I've pulled the oiler off and blew out what I could an it appeared clean. I've seen lots of post about oiler not working but nothing about building pressure. It keeps blowing out the little steel ball bearing that's in the oiler circled in the picture. I haven't tore down the rest of the saw because I'm not sure what I would be looking for. Any help/tips would be appreciated.

 

[heimannm]

The outlet route for the oiler must be blocked, is it oiling the chain at all? There is one internal check valve (ball and spring) "down stream" from the manual portion of the pump and if it is sticking, the automatic portion of the pump can build pressure internally and lock up the pump as you have experienced. In theory, the outlet check valve is not serviceable, but it is possible to pull the steel sleeve from the pump body and clean/clear the passages.

This is a later version of the oil pump with an integral check valve that I have not managed to service, but you can see the spring and check ball on the outlet side as well. If you disassemble the pump, take note of how far the steel sleeve is pressed into the pump body. I think the bottom out against a shoulder in the bore but I can't remember specifically right now.



Easiest solution (provided the path from the pump to the bar pad is clear) would be to buy a new oiler. I have them, Max (Knightmax) has them, and you can find them on eBay. Otherwise, I have gaskets & diaphragms if you choose to rebuild yours.

This is on older version of the oiler that uses the same disc check valve as the 10 Series McCulloch saws.



The diaphragms are different depending on which inlet check valve the pump uses.



Mark

 

[hambone8978]

Thanks! That’s kind of what I figured that there was some check valve that’s stuck. I’ll take the oil off and see if I can pull that sleeve out. Any particular tool that you use to get it out?

 

[heimannm]

Long nose Channel lock pliers or Vice Grips will work. If you happen to scar it a little, chuck it in your lathe or drill and buff it out with some emery cloth to make sure the plastic sleeve moves freely.





Mark

 

[heimannm]

Start your project by removing the bar and making sure the oil path to the bar pad is open (work the manual oiler) and verify that the oil passage in the bar is open. If those are both O.K. your only other option is the pump.

It can be a little tricky getting the oil pump out and then back in again with the foam seal in place between the oil pump and the air box.

Mark

 

[hambone8978]

Start your project by removing the bar and making sure the oil path to the bar pad is open (work the manual oiler) and verify that the oil passage in the bar is open. If those are both O.K. your only other option is the pump.

It can be a little tricky getting the oil pump out and then back in again with the foam seal in place between the oil pump and the air box.

Mark

Thanks! I’ll give that a try