Dolmar 64xx/73xx/79xx series, smurfs and solo 665/675/681 thread

[Lightning Performance]

The same part on a husky or stihl is metal. Not sure why they made it out of plastic. It’s very easy to replace and inexpensive though. However it’s something that shouldn’t be a problem in the first place... Metal would have been better.

If the pump jams your plastic part will give up first.

 

[mettee]

I think a stainless one would be nice. Do you guys think there is a need for them, or at least enough if I make them?

Still need to zip out some velocity stacks.

 

[huskyboy]

I think a stainless one would be nice. Do you guys think there is a need for them, or at least enough if I make them?

Still need to zip out some velocity stacks.

I would probably buy one from you if you had them made

 

[Flint Mitch]

I would probably buy one from you if you had them made

As would I

Sent from my SM-G892A using Tapatalk

 

[huskyboy]

Make sure you copy the offset on the white adjuster if you decide to make them, not the black one. White one has more offset, puts out more oil. I had to increase the ramp on the oiler piston when I used the black adjuster to get a full tank of oil used for a tank of gas. You could probably play with more offset on the metal copy, maybe .010 more offset would be nice. Also, the oem adjuster nub has a slightly rounded end, not cut flat. If you made the end flat on the metal copy it would probably dig/wear more into the piston ramp over time.

 

[Lightning Performance]

Make sure you copy the offset on the white adjuster if you decide to make them, not the black one. White one has more offset, puts out more oil. I had to increase the ramp on the oiler piston when I used the black adjuster to get a full tank of oil used for a tank of gas. You could probably play with more offset on the metal copy, maybe .010 more offset would be nice. Also, the oem adjuster nub has a slightly rounded end, not cut flat. If you made the end flat on the metal copy it would probably dig/wear more into the piston ramp over time.

Close up pics

 

[Lightning Performance]

I think a stainless one would be nice. Do you guys think there is a need for them, or at least enough if I make them?

Still need to zip out some velocity stacks.

V-stacks... for Dolkitas 64-7900?

 

[mettee]

Yes, its kinda a full system, mix of the best of both worlds for filtering and performance(K&N with pre) and a huge stack in the HD housing. Have to use the HD housing to fit it.

 

[Lightning Performance]

Yes, its kinda a full system, mix of the best of both worlds for filtering and performance(K&N with pre) and a huge stack in the HD housing. Have to use the HD housing to fit it.

No Thanks

 

[PA Dan]

Yes, its kinda a full system, mix of the best of both worlds for filtering and performance(K&N with pre) and a huge stack in the HD housing. Have to use the HD housing to fit it.

Get r done...[emoji6]

 

[NPKenny]

I think a stainless one would be nice. Do you guys think there is a need for them, or at least enough if I make them?.

I’ll take two. Say when.

@mettee

 

[stranter]

Wonder if anyone can ahead some light on this Makita 7900.
Colleague heard a nasty noise while pulling over his saw. Long story short I pulled the cylinder off to discover it had broken at the base! Luckily I had a spare lying about so tried to rebuild, but discovered the crankcase had cracked when I pressure/vac tested it. It appears that the force of the cylinder breaking had also cracked the case.
I ported the original cylinder, so conscious it could be something I did wrong, although never had this problem before. The build was base gasket delete and the lowers were case matched and blended, intake and exhaust were widened and smoothed, but no timing change (other than BGD). I torqued down the cylinder bolts with locktite to spec also.
Any ideas what has happened here? Could it be a casting flaw?

 

[stranter]

Sorry Tapatalk only allows 1 pic per post

 

[stranter]

 

[stranter]

 

[huskihl]

How were the old bearings when you pulled it apart? Maybe they gave out and allowed the piston to hit the band?

 

[dahmer]

Weren’t some of these a really tight fit and you couldn’t do a base gasket delete?

 

[stranter]

How were the old bearings when you pulled it apart? Maybe they gave out and allowed the piston to hit the band?

The bearings were perfect when I built it as only had 25 hours or so use from new. I’ll double check, but I don’t think it has more than 100 hours on now!

 

[stranter]

Weren’t some of these a really tight fit and you couldn’t do a base gasket delete?

I just went back and checked my notes. Was right at 0.019” for squish. So possibly a bit tight but ex at 108 so had bags of compression.

 

[Lightning Performance]

I just went back and checked my notes. Was right at 0.019” for squish. So possibly a bit tight but ex at 108 so had bags of compression.

Na. My work saw is @ 0.014 so is my ms362