Makita 520-i Bar Oil Leak between case and suction line (020-245-041)

[Schoolteacher]

Makita/Dolmar buffs:

We are repairing a pesky bar oil leak on the 520-i. After removing the clutch, and bar oil suction line ,cleaning the case and re-seating the oil pump suction line the leak remains. The search function here has some info on sealing the opening between the round hole in the case and the rubber gromlet on the suction line with automotive silicone gasket maker/sealer and that has worked. The original replacement part is 020245-040 Now obsolete and it has been replaced by 020-245-041. We have the replacement part on order, just wondering if this is a common design flaw on the Makita 520-i?
Do they seal the suction line from the factory or is it normally just a a press fit? We will use the sealant if we have to as a last resort. Thanks.

 

[makguy]

It's not a design flaw, but it is common. The reason it occurs is because as the saw is used, heat and age hardens and shrinks the rubber lines so that they don't seal as well.
The solution is to either replace the line with a new one (which is still available from Makita) or use a gasket sealant like permatex around the sealing surface when you reinstall the old line. Just make sure that you clean all the oil off before you use the sealant

 

[nstueve]

It's not a design flaw, but it is common. The reason it occurs is because as the saw is used, heat and age hardens and shrinks the rubber lines so that they don't seal as well.
The solution is to either replace the line with a new one (which is still available from Makita) or use a gasket sealant like permatex around the sealing surface when you reinstall the old line. Just make sure that you clean all the oil off before you use the sealant

Permatex and other sealants have 50-50 hit and miss on this repair. The best solution is a new line. I've replaced at least 12 of these. I've also used gas line grommets from bad Stihl fuel lines and tygon to repair this problem. Next time you just swap the tygon line.

Here is a link to ipl.
http://www.barrettsmallengine.com/partslist/dolmarpartslist995700064-2.pdf

 

[Poleman]

Had the same problem with this....leaked all over all the time. Very disturbing.

What I did was put 2-3 small washers behind the tube to push it closer to the oil pump and make it tighter. That was after I Permatexed the oil hose seal that goes into the tank ( which I thought where the leak was and it still continued. I then replaced the hose to the tank...still had a leak. I looked close at the the fitting and discovered it was leaking from the tube that goes to the bar grove. It is just a preasure seal and not a good on after time and use...thus the washers to shim it closer. I just chose washers that fit snuggly into the area. Now it still drips but its off the chain...it oils like a Texas oil well.

H