Porting my trimmer

[Fly By Night]

I lowered/widened my exhaust today, opened up the muffler more,reassembled with out base gasket and got a squish of .024". I got it to run, its not totally happy and revs higher at 3/4 throttle then full, I think it needs more fuel. I ran a compression test warm and got 140psi, added oil and got 210 right at first, It sounded to me like the oil was trying to burn some, once my gauge leaked down a little and I tried it again I was getting 180 psi, that increase of 40 psi makes me think rings are a GREAT idea, like a member recommended in this thread awhile ago. It seems to run a little better, I think a tune-able carb should get it pretty happy, I wish at this point I didnt touch the jug with a grinder. Hopefully rings and not running real lean will wake her up nicely.

 

[jughead500]

Have you looked thru the tanaka ipl's for bigger main jets? Im thinking that im going to have to get a few size larger main since I modded the muffler on the 340.

 

[Fly By Night]

I have not, I think mines is .38, I have a few other WYK carbs around with different jets and have mixed and matched the .42 was wayy too much fuel, I may drill mine to .40 and see if thats a happy medium, ultimately I think being adjustable will be the best.

i just ran it more, its defiantly some degree happier, I'm excited to see what it will do when the compression and jetting are where they should be.

 

[jughead500]

Yeap I like the wyk carburetor for reliability but the non adjustable part sucks.if you do happen to find an adjustable carb that works keep me informed.looks like some of the older tanaka models have hda's so thosr could be an option.echo also used the bakelight intakes so those could also be adapted.

 

[Fly By Night]

Sorry these have a WYJ their WYK is identical with an adjustable high end. Ive spent hrs looking at this, same bolt pattern, throttle position ect, it looks to be a drop in replacement with adjust ability.

http://wem.walbro.com/distributors/servicemanuals/WYKseries.pdf

 

[jughead500]

Oh yeah I meant wyk but tapped wyj.lol
Hmm thats interesting.

 

[jughead500]

Looks as though this would work.
http://m.ebay.com/itm/311132719276?nav=SEARCH

 

[Fly By Night]

Im guessing you size your main a smidge smaller then ideal and compensate with the extra high end fuel? I have no idea how much or little fuel that circuit can provide and how fine tune able it is, Thats what I want to know to size a main jet in one. Ill probably drill out my current one to .40 and see what that gets me and go from there.

 

[Fly By Night]

The ebay one doesn't have main/venturi sizes posted, id bet they are both too large for the my trimmer at altitude.

I want to keep the same size venturi and preferable get a .35 jet if I can, if not ill make the right size jet, i cant change the venturi size.

 

[dozerdan]

Only an idiot would port a trimmer: http://www.arboristsite.com/community/threads/ported-poulan-pro-pole-pruner.276194/

I ported my Stihl FS 85 trimmer years ago. Its running a carb off of a Stihl 026.


Later
Dan

 

[jughead500]

I may order one of those ebay chinese carbs to play around with on my 340.those look to have the high speed adjustment screw.i haven't dug too deep into what carbs fit what and cross over but the 38 size main jet covers the 260-340 as far as i can tell.then they skip to 42 and 44 on the larger models.
I tried my 340 the other day and its vibrating itself apart.so its time for a little r&r for it.7-8 years and its been flawless.i've gotten 3-4 years more use from it than the rest i have went through over the years.a trimmer is one thing that gets total abuse from me.i use the tanaka more than my fs250.in the meantime i have already worn one of those out and bought another.
The 280pfl is working out great.where i was taking a 6 foot swath i'm now able to do at least an 8 foot swath each pass.i don't have to climb in ditches as far.and get less grass all over me.the only thing though.the longer slightly skinnier shaft has a little more flex and i keep running into the line head when i walk around my truck.lol

 

[Fly By Night]

There is a spot on walbros website where you can find venturi and jet size off of the part number. I think its their parts lookup.

I'm Jelous of your 280PFL Bastard

Sometime when things get that long they get a little bouncy

 

[jughead500]

eat your heart out.lol i'll post pictures tomorrow.
The 280 seems to have a little less power than the 340.in a way i wish i could have got the 260 but i'm thinking weight would have been the same with a tad less power.right now with the 280 and long shaft the weight is up there with the 340.still a killer after 1\2 acre.

 

[Fly By Night]

I might be interested in a power head swap

 

[Fly By Night]

I punched out my main jet a bit today .
it seems happier, I need to get some run time on it to see what color that plug turns. The way my lighting was I could see it would smoke just a teeny bit when I first nailed it, it must have an accelerator pump! If only

 

[Rx7man]

The spot I would look at for improving transfer flow is the radius around that bottom bolthole, blending things in there as much as possible.. that looks to me like more of a bottleneck than anything else.. my $.01

 

[jughead500]

Well fly by night looks like i get to do the same as your doing to my tbc340.mine laid down on me yesterday.finally after 8 years of killing big weeds and clumps of fescue it got til it wouldn't idle and was vibrating all over the place when i did get it running.noticed some scratching on the piston and there was a small scratch on the flywheel magnet where it had made a litte contact with the coil.
Oh well it doesn't owe me anything.

 

[Fly By Night]

Are you going to overhaul it?

 

[jughead500]

Are you going to overhaul it?

Yeah bearings, rings, seals, gaskets.maybe open up the ports some.didn't realize it but the intake and carb are small for 32cc.looks to be a universal size for tanaka.the carb spacer looks to have the same size as probably the 260 and 280.
Definately going to try the bigger adjustable chinese carb just for giggles.

 

[Fly By Night]

That sounds like it's going to turn into a brush hog!