Dolmar 7900 Carb upgrade?

[LegDeLimber]

Smaller gap should fire a Gnat-sneeze earlir , due to breakdown voltgae (of air gap) achived sooner.
Probly get far more result from finding longer reach plig and some spacer/washers
to set the depth/disrtance that plug protudes into chamber.

But gatta be Damn sure to chek cleances!!! dont want to have the piston hit and get a hole/crack in it.

then there's also the indexng of the strap/ground elctrod factor to also to alter and look for any improvmnts.

sorry i'm having al ittle messy typing day, fellows

 

[Fly By Night]

I just looked for a farmer tec carb and cant find them on Ebay, do you happen to have a link Rich?

 

[Poleman]

Hutzl. On eBay carrys the Farmertec carbs and priducts. I also use the 272 coils they have to unlimit the 7900's.

 

[Paragon Builder]

I just looked for a farmer tec carb and cant find them on Ebay, do you happen to have a link Rich?

I couldn't find any carbs for the dolmar saws on ebay either. Plenty of carb kits but no carbs. Is there a Zama part number we can search for?

 

[Poleman]

Item: Husqvarna Chainsaw 362 365 372 371 372XP Carburetor 503 28 32-03, 5032818-01

URL: http://pages.ebay.com/link/?nav=item.view&id=291047828269

Alt URL: http://www.ebay.com/itm/Husqvarna-C...buretor-503-28-32-03-5032818-01-/291047828269

 

[Paragon Builder]

Item: Husqvarna Chainsaw 362 365 372 371 372XP Carburetor 503 28 32-03, 5032818-01

URL: http://pages.ebay.com/link/?nav=item.view&id=291047828269

Alt URL: http://www.ebay.com/itm/Husqvarna-C...buretor-503-28-32-03-5032818-01-/291047828269

Great! Thanks. I didn't realize they shared a carb with those Huskys.

 

[Poleman]

I use the A.M carbs from a Husky 362-372....the only difference is the choke hole is larger where the choke lever attaches on the carb. I have never had an issue with it coming out.

OEM, are $75-$105 in comparison to the aftermarket. The casting quality isn't quite the same but the machining is as good or better than the Zamas.

Of all the carbs I've worked with (AM) I've only had two that weren't right. I have very good luck with them.

 

[Poleman]

With the older ones they do. This mod also work on them.
The new extorque uses a different WJ carb and are totally different.


Item: New Replacement Carburetor Carb Fits Husqvarna 362 365 371 372

URL: http://pages.ebay.com/link/?nav=item.view&id=281066370635

Alt URL: http://www.ebay.com/itm/New-Replacement-Carburetor-Carb-Fits-Husqvarna-362-365-371-372-/281066370635

Here's another supplier.... Their carb have Zama on them and the have very prominent main jets and east to pull. The jet is also a slightly different design which I like also.

 

[cgraham1]

Bump!

 

[Paragon Builder]

Bump!
View attachment 433587

Nice! Did you just get her back?

 

[cgraham1]

Nice! Did you just get her back?

I've had it for quite a while. I just saw this in my watched threads, and thought it could use a bump.

 

[cgraham1]

Nice! Did you just get her back?

Its been done for quite a while. I just saw this in my watched threads, and thought it could use a bump.

 

[Paragon Builder]

Guess I'm not the only one getting double posts this morning...
Is that saw randy sent to rich to play with after he was done?

 

[mdavlee]

I got a couple of these carbs to play with soon. With all the rain this weekend I may have more time inside and less outdoors

 

[fordf150]

Guess I'm not the only one getting double posts this morning...
Is that saw randy sent to rich to play with after he was done?

clint just did that to up his "like" count. i had to like all 3 posts

 

[cgraham1]

Guess I'm not the only one getting double posts this morning...
Is that saw randy sent to rich to play with after he was done?

Yep.

clint just did that to up his "like" count. i had to like all 3 posts

 

[Paragon Builder]

Did you get to try it with and without the carb mod?

 

[cgraham1]

Did you get to try it with and without the carb mod?

No, I did not. In fact, I put my stock carb on a different saw and sold the saw.

 

[Terry Syd]

As long as you bumped this thread, I've tried something else with the Walbros.

I have a mate who bought a cheap Chinese saw (71cc) with a 15mm HDA on it. (The HDA doesn't have the better staged transition ports that the HD has). The carb needed a heap more low speed circuit flow and I turned up the low speed needle. That made the idle way too rich and I had to turn in the idle screw a bunch to keep it idling (rough as it was). The throttle response was also too rich - but it did cut wood well.

I was thinking of drilling out the transition holes - and then had an idea after looking at the lightweight spring in the carb. The carb would take a Zama spring and I had a good selection of stronger springs. If I used a spring that was much longer, it would lean out the idle and give a better transition. I looked through the springs and found a packet of three springs that are used on stationary engines.

Not only was the spring longer, but it was a thicker wire and wound with more pitch - it was a lot stronger than the stock spring. The stronger rate of the spring would also slow the ramp in of the fuel from the low speed needle. OK, if it was too strong I could always trim it back. So, I put the spring in the carb and started the saw.

Since the idle screw had been turned in so much, the saw was idling quite high. I turned down the idle screw - and the freaking thing idled perfectly. Then I hit the throttle and the response was crisp and clean. It was like the spring was made for that saw!

So, for you Walbro enthusiasts, you may want to get one of those spring kits with all the different Walbro springs in it. You may be able to use a different spring to clean up the idle/transition rather than pull the welch plug and re-drill the carb.

 

[one.man.band]

very nice TS and tyvm.