Dolmar/makita 7900 oil mod

[WoodsliverDan]

I've got an idea to help the 7900 saws get a bit more oil on the chain, or at least make the adjuster screw last a little longer. Most have seen @jar944 oiler screw he turned out of 6160, but I realize that it is out of many people's resources. So, I plan to remove the end nub off of the plastic adjuster screw (this is what controls flow) and drill a small hole in the end to epoxy a small wire or weld rod in its place. This way I can make the end nub a bit longer and more than likely, more durable. Of course, filing the gear shaft end to a steeper angle as well. Tell me your thoughts..

 

[WoodsliverDan]

I will get some pictures up when I get more done on idea.

 

[nwroller]

Interested. I just got a 6421. I run a 28” bar often and while I feel it is oiled ok would give me piece of mind since that’s the only negative people seem to have on the saw.

I understand the Oiler is the same on the 6400/7900.

 

[WoodsliverDan]

Yes the oiler is the same. A lot of folks currently just file/grind the shaft gear to a steep angle. ~10° steeper should give you more flow. I'm trying to address two problems here. One being the plastic nub on the end of the adjuster screw. Since they're plastic, the nub eventually wears out and oil out put slowly diminishes. I'm hoping the steel insert will make it more durable..

 

[James Miller]

I'll be watching this thread to see how your mods work out. Putting a 32 on my 7910 tomorrow to work up some big oak. Ill keep an eye on how it oils the bigger bar.

 

[WoodsliverDan]

How did it oil with 32", @James Miller ?

 

[James Miller]

This is as close as it got to running today. When I got to my spot the tree service had bucked the big stuff with there 661. I know where theres a 40+" maple I can bury it in tomorrow. Was really hoping to try it in the oak today but oh well.

 

[WoodsliverDan]

How do you like the way the saw feels with that full weight 32? Some maple is hard too!

 

[James Miller]

Its definitely nose heavy. Theres a 28" tsumara light and tuff bar on the way for it. The 32 is off another members 395 and will be returned soon.

 

[KiwiBro]

32" is all it wants to oil in our wood down here. At times it's probably just a pinch too much for the stock oiler on my 7900.

 

[WoodsliverDan]

Its definitely nose heavy. Theres a 28" tsumara light and tuff bar on the way for it. The 32 is off another members 395 and will be returned soon.

I run a 28 light and thought tsumura on mine and I think it balances very nicely.