Mastermind Ported Dolmar 6100

[Terry Syd]

Randy, something Poleman and I ran into was the jet having a 'valve' under it, that is, a small thin piece of plastic. It seems to be an EPA thing as I have run into them on a number of carbs.

The jet you took out of the EL-42 could give you an idea if it has the 'valve'.

If it has the valve, you don't want to push the film out of place by pushing the drill too far into the jet, it might block the outlet of the chamber. Just take it easy as you drill out the last bit of the jet so that the drill doesn't 'plunge' through the jet and into the film.

EDIT: We both have drilled holes through the film, dislodged them and run without them - and didn't notice any difference. However, they could be important in some carbs as they may act like the valve in the main discharge nozzle to keep the air from flowing into the wetside when the engine is idling for a long time.

 

[Woodpecker]

Terry you are definitely a carb guru. It's going to take me awhile to wrap my 2 remaining brain cells around all this! Over my pay grade, but good stuff for sure.

 

[Terry Syd]

I'm just sharing the knowledge and experience I've picked up, sometimes 'inadvertently'. Give Randy a few weeks and he'll be a carb guru.

 

[bryanr2]

Randy I suspect you'll see a 6100 boom on scheduled port work. Looks like a mighty venerable saw.

 

[Mastermind]

I didn't see a valve in the brass jet Terry, but in gonna assume it will have one, and drill carefully. The hole that feeds from the jet well, into the transition area will need to be enlarged too. So I'll be pulling the welch plug.

 

[Poleman]

Randy, these are the brass washers I use to shim springs.

 

[Mastermind]

Their website ain't working for me.

 

[Poleman]

Rats....me either.....

 

[Poleman]

Got a bag I can send you Randy, if you'd like them.

 

[Mastermind]

Got a bag I can send you Randy, if you'd like them.

I found another source. Once I knew that I was after 1.4mm washers.......well that really helped Rich. Thanks brother.

 

[Woodpecker]

I'm just sharing the knowledge and experience I've picked up, sometimes 'inadvertently'. Give Randy a few weeks and he'll be a carb guru.

Good on ya! That right there is what I like best about this place!

 

[Terry Syd]

I didn't see a valve in the brass jet Terry, but in gonna assume it will have one, and drill carefully. The hole that feeds from the jet well, into the transition area will need to be enlarged too. So I'll be pulling the welch plug.

Hopefully it doesn't have the 'valve', never could figure out what the damn thing did. I mentioned the possibility of it blocking air, but at an idle fuel would be going though it in one direction and the air would have to go against the fuel flow. Thought about a few other things, but nothing made sense - it is a special secret 'mystery' valve only known to true carb gurus.

If you are going to drill the transition welch plug for testing, wait and see where the jet size ends up before drilling the feed hole from the jet well. The passage way is likely .5mm (a common size in carbs) and if you end up with a .40mm jet, then you should be fine.

 

[David Young]

I found another source. Once I knew that I was after 1.4mm washers.......well that really helped Rich. Thanks brother.

Randy where did you find the washers? Do you have a link?

 

[Mastermind]

I'll try to find one.

 

[exSW]

Since this thread morphed into a carb thread I got an issue. Zama C1Q E3 on a brushcutter. Won't tune. New kit ,USCed both myself and the dealer can't get it right. Constantly runs rich even with the screws turned in. $91.00 bucks through Efco and 38.00 on eBay. Any wisdom.

 

[Stihlbro]

Close off the l and h adjustment. Presssure test from the fuel inlet. Dunk it in a jar of gas and tell us where the bubbles come from.

 

[exSW]

No bubbles.

 

[Stihlbro]

Picture of what is under the metering diaphragm would help.

 

[Redfin]

Close off the l and h adjustment. Presssure test from the fuel inlet. Dunk it in a jar of gas and tell us where the bubbles come from.

Are you trying to keep the pressure under what the pop off is for this test or just slightly over?

 

[exSW]

Picture of what is under the metering diaphragm would help.

Going to have to wait a day or three. Got in last night at 2330,will be gone again before midnight. You guys carry on. I'll catch up.