Engine Trouble 47cc Tanaka stalls

locksmith · Sep 13, 2013

ok, i went to the shop yesterday to pick it up and started it only to find the exact same problem... it stalls.

he ran carb cleaner through it and adjusted the jets. then his son came out and told me he's gonna have to put a new carb on. i'll see what happens... looks like headsmess was right

the next part is a bit strange... he's a small engine mechanic (mostly mowers) and told me he hates weed-eater engines because he always has trouble with them. he said tanaka is junk and they sell them for a lot more than they are worth... as an "insider" he can get one for like $100 bucks. he said it'd run a lot better with a chainsaw motor attached... frankly, i think he's crazy. i've had 7 stand up scooters and one bike and they've all been great

the one thing i did notice is that the tunable carbs are a huge pain in the ass. my 35cc tanaka always started and ran well as does my 40cc purefire...

so yeah, what do you think?

5-7HEAVEN · Sep 14, 2013

I used to have a starting problem with my Tanaka. My arm would hurt yanking that pullstart.
Now it starts fine after a few pulls and a warm up. Why would you need a new carb? Just rebuild it, if you must.
You DO have a fuel filter, correct? Are you using the OEM saddle tank alone?
On my brand new Mitsubishi TLE43 engine, the engine would stall after a mile.
Thank goodness I had a SECOND engine on the front, so I "hobbled" home on one engine, lol.
Problem was the tank not venting. When I loosened the gas cap, engine started up and ran fine.....as long as the cap was loose.
So I put a toothpick in the tank's fuel line grommet, next to the fuel line.
After 50 miles running, all the gaskets and grommets loosened up. I removed the toothpick and the engine ran fine ever since.
Does it stall as you tip into the throttle, or cruising at speed? Did you try raising the idle?
Did you clean out the muffler? When it stalls, does the engine start right back up?
I liked the no-hassle nonadjustable carb on my Mits engine.
However, I like the tunable carbs, especially if you screw up the fuel/oil mix.
Yeah, Tanakas are junk. That's why I keep running them. (sarcasm)

HeadSmess · Sep 14, 2013

if a petrol engine is left for any length of time, ie over a season, ensure there is no fuel left in the system or it dries out and gums everything up.

that is ALL petrol engines.

across 90% of small twostrokes i work on, i invariably smell rotten fuel in the tank/lines/or carb as i dismantle it.

90% of these are running engines after a simple strip and clean.

the other 11% require more serious work to get running, some just being scrap metal. the blocked vent on the fuel tank and perished fuel lines comes close second and third place for usual problems.

loss of chrome plating, from straight fuel is pretty common. they start and run for a few minutes then wont start till cool again. ad nauseum.

strip and clean the carb yourself. 4 to 8 screws and compressed air... it sure sounds like the shop you go to doesnt know what theyre doing. id hate to think what they do if they come across an early slide walbro... or the LPG carbs used on some of the lil 4strokes...

thing with adjustable carbs is you can adjust them. theres a reason the guys that compete replace the new unadjustable carbs for dual needles...

the best small engines to use? the same ones that you see commercial lawnmowers and landscapers using...Honda, Kawasaki, Shindaiwa...

the worst engines to use? take a trip to the scrap yard one day

though they also hold to that 90% rule...most are just gummed up carbs owned by people that know no better, and its cheaper to buy another ryobi than fix it...

where else can you buy 50 walbro carbs for 30 dollars?

locksmith · Sep 16, 2013

i just spoke to the shop today... he told me it's not even starting. i dunno if he broke it or what, but he told me he was soaking the carb, and he may have to buy a new one if i want which would be 100$...

i'm really starting to question their competence

5-7HEAVEN said:
I used to have a starting problem with my Tanaka. My arm would hurt yanking that pullstart.
Now it starts fine after a few pulls and a warm up. Why would you need a new carb? Just rebuild it, if you must.
You DO have a fuel filter, correct? Are you using the OEM saddle tank alone?
On my brand new Mitsubishi TLE43 engine, the engine would stall after a mile.
Thank goodness I had a SECOND engine on the front, so I "hobbled" home on one engine, lol.
Problem was the tank not venting. When I loosened the gas cap, engine started up and ran fine.....as long as the cap was loose.
So I put a toothpick in the tank's fuel line grommet, next to the fuel line.
After 50 miles running, all the gaskets and grommets loosened up. I removed the toothpick and the engine ran fine ever since.
Does it stall as you tip into the throttle, or cruising at speed? Did you try raising the idle?
Did you clean out the muffler? When it stalls, does the engine start right back up?
I liked the no-hassle nonadjustable carb on my Mits engine.
However, I like the tunable carbs, especially if you screw up the fuel/oil mix.
Yeah, Tanakas are junk. That's why I keep running them. (sarcasm)

I will check the fuel tank and try the toothpick trick... The problem was it would start, rev, and then die upon returning to idle

It does start back up (or did, i dunno what state it's in now)

HeadSmess said:
if a petrol engine is left for any length of time, ie over a season, ensure there is no fuel left in the system or it dries out and gums everything up.

that is ALL petrol engines.

across 90% of small twostrokes i work on, i invariably smell rotten fuel in the tank/lines/or carb as i dismantle it.

90% of these are running engines after a simple strip and clean.

the other 11% require more serious work to get running, some just being scrap metal. the blocked vent on the fuel tank and perished fuel lines comes close second and third place for usual problems.

loss of chrome plating, from straight fuel is pretty common. they start and run for a few minutes then wont start till cool again. ad nauseum.

strip and clean the carb yourself. 4 to 8 screws and compressed air... it sure sounds like the shop you go to doesnt know what theyre doing. id hate to think what they do if they come across an early slide walbro... or the LPG carbs used on some of the lil 4strokes...

thing with adjustable carbs is you can adjust them. theres a reason the guys that compete replace the new unadjustable carbs for dual needles...

the best small engines to use? the same ones that you see commercial lawnmowers and landscapers using...Honda, Kawasaki, Shindaiwa...

the worst engines to use? take a trip to the scrap yard one day though they also hold to that 90% rule...most are just gummed up carbs owned by people that know no better, and its cheaper to buy another ryobi than fix it...

where else can you buy 50 walbro carbs for 30 dollars?

that's what the previous owner (retard) did.

would this be any good?

http://www.ebay.com/itm/Tanaka-6502...042?pt=LH_DefaultDomain_0&hash=item232ea2c6e2

thank you both for your support

-----------

also, my biggest fear at this point is these jerks have just run the poor thing to death troubleshooting and broken it

they make everything sound like it's a shot in the dark.

HeadSmess · Sep 17, 2013

locksmith said:
have to buy a new one if i want which would be 100$...

(can get a new one on fleabay for a third of that. doesnt have to be the same MODEL, just the same bore. the same type of throttle linkage also helps save on frustration.)

i'm really starting to question their competence

(i did from the word go and i havent even dealt with them! this "job" takes all of half an hour! these guys hail from deep down alabama way or something? sound like a bunch of hayseeds! the boy, is his mother his sister too?)

I will check the fuel tank and try the toothpick trick... The problem was it would start, rev, and then die upon returning to idle

(if it would rev and stay revving for a while, or run basically normal at half throttle and over... the tank vent isnt the problem. if it would start, and just rev then die...vent. loosening the tank cap will prove aye or nay
instead...sounds like a blocked orifice in the low speed circuit. once again, strip and clean. soaking? what sort of SHOP thinks SOAKING a carb will do anything? the thing needs "shellac" removed from within. pull it apart and soak it overnight in acetone (be careful it doesnt dissolve the diaphgrams!) or similar if anything, then give a good blow with compressed air)

that's what the previous owner (retard) did.

(as you said in the first post. i said strip the carb! once again, its only a few screws, a lil patience and some decent solvent and compressed air)

would this be any good?

http://www.ebay.com/itm/Tanaka-6502...042?pt=LH_DefaultDomain_0&hash=item232ea2c6e2

(no idea, it doesnt say what type of carb it comes off, just engine, and whos to say that you have that same carb still? its best to note down any numbers on the carb itself, and do a specific search for that. personally, i have several rebuild kits kicking around, ive never used a complete kit, just replaced a diaphgram or something as necessary. those kits contain everything but the carb body. filter screens, lil walsh plugs, etc etc. try the strip and clean FIRST. get a collection of carbs together, you can do a lot with mixing and matching once again...scrap yard is the cheapest source.)

thank you both for your support

(no probs, hope youre learning these things are SIMPLE.)
-----------

also, my biggest fear at this point is these jerks have just run the poor thing to death troubleshooting and broken it.

(true but unlikely. just a carb issue at the moment. last thought...there is a lil hole in the manifold block, and a hole in the carb, right next to its "throat". this provides a pulse from the crankcase, for driving the pump inside the carb. all to often i see the hole blocked up with silicone or sealant, or the gasket has been placed the wrong way round...blocking the hole. check! just be aware that some engines (usually chainsaws) use a seperate hose that runs from carb to crankcase instead of the internal hole... obviously i havent played with the specific engine you have. no prob, theyre all the same to a certain degree)

they make everything sound like it's a shot in the dark.

(wont be a problem once you start working on them yourself . save some money, and dont line some hill billies wallet...)

zippy zippy zippy this is just my post to make the post long enough to post

and, lol! as an "outsider" i can get a honda 25 for a grand total of $100... heh heh heh

aussie dollars, tooooooo

locksmith · Sep 19, 2013

got it back today... they didn't charge me, and he told me its 90% chance that the carb is broken.

he told me the two jets (for lack of better term) that suck the fuel in and spit it back into the tank are broken and not doing their job.

any ideas?

i'm prepared to work on this myself and will take it off for pics or whatever if necessary.

thanks.

here is the exact carb: http://www.ebay.com/itm/Original-Wa...851?pt=LH_DefaultDomain_0&hash=item5ae8bb362b

i'm gonna see if i can find one that's the same size... it's basically just a large chainsaw carb

possible similarity:

http://www.ebay.com/itm/NEW-Carbure...d=100005&prg=1088&rk=2&rkt=4&sd=390451639851&

5-7HEAVEN · Sep 19, 2013

Glad you got it back w/no charge.
You need to fix it yourself. Like heads said, the carb has few moving parts.
"Jets" are not broken. Maybe the diaphragm which sucks fuel is ripped.
You have absolutely nothing to lose by disassembling the carb and inspecting it.
FWIW, the walbro carb on my CY460 engine had a return port on the carb.
Instead of installing a return line to the tank, I just pluggedf the return line.
Engine ran fine with plugged return port.

HeadSmess · Sep 20, 2013

return line can be blocked or not. if it has a primer, leave it unblocked or you wont prime too easy. just um...be aware it will squirt fuel everywhere when primed

back in the day i fitted a 1oz rc fuel tank as a lil baby priming tank just for this reason. one line to tank only, at other end of bike... that brushcutter fuel line is freakin expensive stuff!

normally, being me...id just let it squirt

it wont squirt when running. that is fine

your ebay link.

middle row, left hand side. that lil black thing is the valve diaphgram. those two lil flaps line up with holes drilled in carb body. plain simple reed valves. one in one out.

you pull apart your carb, you should see all those pieces.

be careful of the gaskets unless you really do want to buy that rebuild kit

but. basically. note which way its assembled and it should go back no probs.

check everything for holes or tears. CLEAN THORUGHLY WITH COMPRESSED AIR.

very rare for the pump to give trouble.

if its acting up, like these morons are saying...once again, check the pulse feed for the pump FIRST!

just unscrew the carb and see!

cus if its blocked... simple fix.

i wont repeat where it is

HeadSmess · Sep 20, 2013

locksmith said:
possible similarity:

http://www.ebay.com/itm/NEW-Carbure...d=100005&prg=1088&rk=2&rkt=4&sd=390451639851&

close, but COMPLETLEY DIFFERENT. that strange oval vent on top looks suspiciously like some sort of strange pulse feed.

MOST CHAINSAW PULSE LINES ARE EXTERNAL. MOST EVERYTHING ELSE IS INTERNAL.

and that first one, all i get is a walbro symbol, no pic.

what you want is something that looks like this...

http://www.ebay.com/itm/OEM-WALBRO-CARBURETOR-WYJ-176-WYJ-176-1-TRIMMERS/130834616757?rt=nc&_trksid=p2047675.m1851&_trkparms=aid%3D222002%26algo%3DSIC.FIT%26ao%3D1%26asc%3D261%26meid%3D1420141750819610434%26pid%3D100005%26prg%3D1088%26rk%3D4%26rkt%3D5%26sd%3D390451639851%26

but not this exact one!

you want a bigger bore one, as fitted to a 50cc polesaw or similar...wlabro has heaps of lists of carbs

locksmith · Sep 21, 2013

ok... today i took of the carb and it was a lot of fun. it's really cool to see how this stuff works. i found this guide that helped me too

http://www.helifreak.com/showthread.php?t=326599

i took a lotta pictures hoping you guys can see something i can't or think of ideas... below i will illustrate what i did and with detailed pictures. oh, and the problem is that the engine suffocates... it's either not getting enough fuel or air and the return jets don't work

walbro hda-97

1. first i took it apart

^this is the diaphragm in question

2. i used compressed air to blast nearly every hole out

^this part is the one with the jets in question... i'm really not sure what the deal is but i blew compressed air into every hole (that sounds weird lol). it's not like blowing through a straw. i dunno how big the holes are or how much air is going through, but blowing into them was like drinking through a coffee straw but even more restricted

3. could the membrane below be blocking anything?

so this is my guess.... please tell me what you think. thanks again.

Engine Trouble 47cc Tanaka stalls

locksmith

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5-7HEAVEN

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HeadSmess

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locksmith

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HeadSmess

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locksmith

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5-7HEAVEN

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HeadSmess

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HeadSmess

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locksmith

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