I removed the clutch with an air ratchet and a tool that I made out of an old socket, here are some pics of the tool.
7900 oiling gremlins
- Thread starter bwalker
- Start date
Help Support Arborist Forum:
TonyM
ArboristSite Guru
I figured I'd end up making something similar to your socket. So are you using an impact to remove the clutch? Is it LH threads?
sedanman
Just cut the piano!!
Air ratchet good, impact wrench bad . Constant torque vs. hammering, saw cranks are multi piece affars pressed together in such a way as to assure proper alignment, not the kind of thing I want to hammer on with an impact wrench. How you choose to destroy, er, treat your equipment is up to you.
Last edited:
I used an impact ratchet, it's easer on the saw. Yes turning the clutch clockwise will loosen it.
TonyM
ArboristSite Guru
Yes, I agree I don't like the impact. So how are you holding the crank with an air ratchet. Piston Stoper?
Ben you type to fast. 
It should come off easy, if you need to, put some rope in the spark plug hole to stop the piston.
It should come off easy, if you need to, put some rope in the spark plug hole to stop the piston.
sedanman
Just cut the piano!!
Rope works real well, don't get into the ports or you could jam the piston. Piston stops are good if you have the right one for the saw in question. I have seen the wrong piston stop punch a hole in perfect (NEW) piston, OUCH! I have NEVER seen rope hurt a piston. Older Dolmar manuals show a locking wedge inserted though the exhaust port. A word of caution, make sure you pull the starter rope out some to avoid using the starter dogs as your piston stop. Be real safe and remove the starter, 4 T-27 screws.
MacDaddy
Addicted to ArboristSite
What do you think a piston stop or a peice of rope does to your piston or crank THINK ABOUT THAT I will use the impact to take the clutch off
sedanman
Just cut the piano!!
Constant pressure between the pto side of the crank and the crank pin, kind of like what the crank was built to handle, or a couple of dozen hammer blows. Nothing for me to think about here. My method is endorsed and recommended by saw manufactures. Show me one service manual that suggests beating on a poor defenseless crankshaft with a hammer, thats what's in your impact wrench, hammers, that's why they call them IMPACT wrenches.
Last edited:
Macman it doesn't take much to remove the clutch, an impact is way more than you really need.
MacDaddy
Addicted to ArboristSite
put presure on one side of your piston and what does that do ropes and piston stops ARE NOT IN THE EXACT CENTER of your piston so that would load your piston on one side that can damage your piston also the first or second impact loosens the clutch and then NO affect on your crank shaft because the clutch is loose also you dont turn the gun up like your taking a tire off Think of it this way what happen to a motor when you turn it over with a little water in the cylinder This has already been talked about on another thread look it up
sedanman
Just cut the piano!!
No amount of typing is going to make either one of us change our minds, you are convinced your way is best, I am convinced my way is best. We will have to agree to disagree on this. This is what makes the world go 'round.
MacDaddy
Addicted to ArboristSite
Sound fine with me I have blisters on my index fingers
All of the dealers I have seen use a impact gun. The clutch isnt on there that tight any way.
TonyM, along with the adhesive stack a few washers underneath the outlet hose to make the fit between the poump and hose tighter.
TonyM, along with the adhesive stack a few washers underneath the outlet hose to make the fit between the poump and hose tighter.
TonyM
ArboristSite Guru
Got it off last night. What do you mean they're not tight. Wow. I had a 1/2" drive ratchet on it, and then almost couldn't get it loose. I used a small rope, and shooved a lot of it in the cylinder, with the piston just closing the ports. That much rope gives a lot and probably distributes the load better than a piston stop. Let it sit overnight to make good and sure the adhesive dried. Started it today and didn't notice anything that would suggest I damaged any internals. Thanks guys.
Dolmar_Tech_Mgr
ArboristSite Operative
Dolmar sells a tool for clutch removal - 944500570 is the part number.
Has Dolmar fixed the leakage problem yet? Mine has begun to leak again albeit alesser amount.
Dolmar_Tech_Mgr
ArboristSite Operative
I have forwarded this link to the factory and as soon as we hear more I will post the information. One thing we have been told is a problem with guide bars primarily from Windsor and Oregon. When using the standard 7 tooth rim sprocket the chain does not pickup all the oil from opening and leakage appears to be the saws fault when in fact it is the bar. I was told by a Windsor rep that there was a change to the EM bar tail and it has been corrected. I have also been told that an 8 tooth rim sprocket reduces the problem at the bar. I will try to push the factory for a tighter seal fix for the oil pump.
Th bar leaking problem only accoured with a 8 pin sprocket and did it with both windsor and oregon bars. The pump leaking is a differant animal. I wonder how Dolmar ever hopes to capture some of the pro market when they have a saw with such a cheesy oiler? The only way tp properly fix this is a new pump design. I have tried the back yard fixes and mine is leaking again, although to a lesser degree this time. Talk about frustrating. 
Mange
Addicted to ArboristSite
How many off thease saws have pump problem?
