Author Topic: More oil from 7900  (Read 1996 times)

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Offline Ducksnuff870

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Re: More oil from 7900
« Reply #10 on: April 14, 2014, 07:45:10 pm »

Offline JP Terp

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Re: More oil from 7900
« Reply #11 on: April 15, 2014, 07:32:52 pm »
Do you have an address or contact info for hotsaws101?   I'd love to get my 7901 to oil more!

Offline jar944

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Re: More oil from 7900
« Reply #12 on: February 09, 2015, 11:33:46 am »
Its a simple mod if you have some tools
Cut the pump rotor angle to 30 degrees (20 is stock) and increase the height on the adjusting "screw" nub. In my case I just made a new screw




Offline 660magnum

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Re: More oil from 7900
« Reply #13 on: February 09, 2015, 11:44:21 am »
Good post on modifying the pump. We needed that.

In rebuilding the oil pump on my year 2006 7900, the little end piece of the plastic adjusting screw was worn off.

So even if you are not going to modify your rotor angle or make a new adjusting screw, It would be a smart move to put a parts kit in your pump if the saw has much use at all on it.

All the later model pro Dolmars have the same design oil pump. The 50cc saws use the black adjusting screw. The ones bigger than a 7900 have a steel adjusting screw. 
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Offline jar944

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Re: More oil from 7900
« Reply #14 on: February 09, 2015, 12:04:25 pm »
If you were wondering the difference was between the white and black adjustment "screws" in the rebuild kit, Its the "nub" offset (about .020".) It allows less movement of the pump rotor and less total flow (in any screw position)



Also regarding the 30 degree angle modification to the rotor, on max output it will about use 1 tank of oil for every .75 tanks of fuel. So watch you don't run out of oil.

Offline mdavlee .

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Re: More oil from 7900
« Reply #15 on: February 09, 2015, 12:44:08 pm »
Glad you made it over here to share. When you going to make a production run of the control bolts? :D

Offline jar944

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Re: More oil from 7900
« Reply #16 on: February 09, 2015, 02:58:21 pm »
Glad you made it over here to share. When you going to make a production run of the control bolts? :D

lol As soon as my wife runs out of things I need to do first.

Offline Cut4fun .

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Re: More oil from 7900
« Reply #17 on: February 09, 2015, 03:08:59 pm »
Nice info. Thank You for joining and sharing with us.


Mike is this the guy doing carb stuff too?

Offline mdavlee .

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Re: More oil from 7900
« Reply #18 on: February 09, 2015, 04:08:04 pm »
No that's Rich who goes by Poleman usually

Offline rayvil01

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Re: More oil from 7900
« Reply #19 on: February 09, 2015, 05:34:55 pm »
Even without a milling machine the rotor adjustment looks do-able with any number of tools.  The screw is another matter. 

Great info. 

Interesting that these saws are light on oil.  Every old Dolmar I ever worked on shot oil like a fountain. 

 

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