Tilloston Carb Questions

Well, I thought I had the 288 running but it is still a no go.

The saw will run good after cranking and then warming up but when you shut it down it will not start back up and has a wet plug.

I was trying to adjust the high needle this afternoon and noticed that when you adjust the hi needle out it wouldn't 4 stroke or lean out so I am guessing I have a bad Hi jet screw. The low jet screw works great. I looked up the kits at bailey's and they don't come with the jet screw.

Do you guy's think this could be the problem? If so where can I find a kit that comes with the jet screws?

tmroper said:

Well, I thought I had the 288 running but it is still a no go.

The saw will run good after cranking and then warming up but when you shut it down it will not start back up and has a wet plug.

I was trying to adjust the high needle this afternoon and noticed that when you adjust the hi needle out it wouldn't 4 stroke or lean out so I am guessing I have a bad Hi jet screw. The low jet screw works great. I looked up the kits at bailey's and they don't come with the jet screw.

Do you guy's think this could be the problem? If so where can I find a kit that comes with the jet screws?

Click to expand...

I supply
OEM Tillotson kits just need to know the carb # to get the correct kit #

someone may have over tighten the H screw and ruined the seat. there is a new 288 carb in the trading post. i would see what it cost.

Lawnmowertech
According to the manual it is an HS 228 but to be certain where do find the number on the carb? If you have one please let me know a price for the kit and what is included. Thanks

Nmurph,
How do you tell if the jet screw has ruined the seat or if it is just a bad jet screw? when you refer to trade post is it a part of this site? Thanks

here is the link to the carb

http://www.arboristsite.com/pp-classifieds/showproduct.php?product=4012&cat=6

usually you can see the tip of the jet is damaged.

Thanks nmurph

another thing you can check , make sure that the vent in the gas tank is venting! i no most times when it dont vent properly, it runs than dies than runs than dies , but sometimes it builds to much presure and floods itself.

its a good idea to make sure that the vent line /valve is not plugged up.

Don't go spending money on a new carb just yet! I'd be willing to bet that you have a governed carb on that saw. Both of my 181SEs and my 288XP have them. There's a big ~1/4" dia. brass screw on the side of the carb right near the choke linkage. Unscrew it - be careful though because they're threadlocked into place and it takes a bit of force to break the threadlocker, and it's easy for the screwdriver head to slip and strip the brass screw. Best to use a fresh flathead screwdriver that isn't rounded over on the end and that fits the groove nice and tight.

Once you get that screw out, you'll be able to see the governor circuit inside the carb and the ball-bearing-and-spring valve mechanism in the screw. The way these work is that after a certain RPM, the spring will compress and open the valve, dumping fuel into the carb throat and effectively flooding the saw a bit. If this valve were to stick open (or spring get too weak) it could definitely flood the saw at lower RPM or after shutoff, I suppose.

If you know what you're doing with tuning by ear, and it sounds like you do, cut a small 1/4" disc from an aluminum can or thin sheet rubber, drop it into the governor hole, and insert the brass screw on top of it. This will block the governor circuit and allow you to tune it like a regular carburetor.

To retune the carb from zero, turn the screws in to where they seat, then out to 1 turn. Start the saw and make sure it'll hold an idle by adjusting the idle screw in. Then tune the H jet to where you get a slight four-stroke sound. Then move on to the L screw - move it just out to where you get a good throttle response and acceleration from idle to wide-open. Make sure the High tuning is still good by opening it to WOT again (sometimes tuning the L jet affects the high end a bit too); then turn the idle adjust screw to where it'll hold a nice even idle without stalling or moving the chain.

tmroper said:

Lawnmowertech
According to the manual it is an HS 228 but to be certain where do find the number on the carb? If you have one please let me know a price for the kit and what is included. Thanks

Nmurph,
How do you tell if the jet screw has ruined the seat or if it is just a bad jet screw? when you refer to trade post is it a part of this site? Thanks

Click to expand...

The #s can be found on the side of the carb the top portion wont have the #s you may have to take it off the saw to see the #s sometimes they have them on the bottom part
http://www.cmsmallengines.net/tillotson-carburetor-kit-rk23hs-rk-23hs-rk23-hs.html
is the kit itself
If you need any of the adjustment needles let me know i can look into availability of them

Brmorgan,
I am going to try that right away. I will let you know how it goes. Gotta admit I am excited to find out.

Lawnmowertech,
Thanks I will get that number for you

Brmorgan said:

Don't go spending money on a new carb just yet! I'd be willing to bet that you have a governed carb on that saw. Both of my 181SEs and my 288XP have them. There's a big ~1/4" dia. brass screw on the side of the carb right near the choke linkage. Unscrew it - be careful though because they're threadlocked into place and it takes a bit of force to break the threadlocker, and it's easy for the screwdriver head to slip and strip the brass screw. Best to use a fresh flathead screwdriver that isn't rounded over on the end and that fits the groove nice and tight.

Once you get that screw out, you'll be able to see the governor circuit inside the carb and the ball-bearing-and-spring valve mechanism in the screw. The way these work is that after a certain RPM, the spring will compress and open the valve, dumping fuel into the carb throat and effectively flooding the saw a bit. If this valve were to stick open (or spring get too weak) it could definitely flood the saw at lower RPM or after shutoff, I suppose.

If you know what you're doing with tuning by ear, and it sounds like you do, cut a small 1/4" disc from an aluminum can or thin sheet rubber, drop it into the governor hole, and insert the brass screw on top of it. This will block the governor circuit and allow you to tune it like a regular carburetor.

To retune the carb from zero, turn the screws in to where they seat, then out to 1 turn. Start the saw and make sure it'll hold an idle by adjusting the idle screw in. Then tune the H jet to where you get a slight four-stroke sound. Then move on to the L screw - move it just out to where you get a good throttle response and acceleration from idle to wide-open. Make sure the High tuning is still good by opening it to WOT again (sometimes tuning the L jet affects the high end a bit too); then turn the idle adjust screw to where it'll hold a nice even idle without stalling or moving the chain.

Click to expand...

Well, I feel kinda dumb now!! I didn't have a clue that's what that was on those carbs. That would explain some of the tuning issues I've had with the 181's and 288's.........One of my 288's just wouldn't tune to where I wanted it on the H needle. It was way rich and that would explain it. That carb must have a weak governor spring......Thanks for the enlightenment, Brad!!

jockeydeuce said:

Well, I feel kinda dumb now!! I didn't have a clue that's what that was on those carbs. That would explain some of the tuning issues I've had with the 181's and 288's.........One of my 288's just wouldn't tune to where I wanted it on the H needle. It was way rich and that would explain it. That carb must have a weak governor spring......Thanks for the enlightenment, Brad!!

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Believe me, I probably still have some bald patches from working on my first ported 181SE a year ago! I could turn that H jet right in to nothing and it would just sit there and bang away on the governor like I was pouring fuel straight down the carb throat. I still haven't blocked the governor on my 288; perhaps I should make a before/after video if I block it so you can hear the difference.

I doubt your spring is/was weak; they're supposed to activate around 10.5K RPM if I remember right, and a decent running 181/281/288 will go well above that. Either way they can make tuning a nightmare; on the upshot I have yet to see a burnt-up one of these saws.

Brmorgan said:

Believe me, I probably still have some bald patches from working on my first ported 181SE a year ago! I could turn that H jet right in to nothing and it would just sit there and bang away on the governor like I was pouring fuel straight down the carb throat. I still haven't blocked the governor on my 288; perhaps I should make a before/after video if I block it so you can hear the difference.

I doubt your spring is/was weak; they're supposed to activate around 10.5K RPM if I remember right, and a decent running 181/281/288 will go well above that. Either way they can make tuning a nightmare; on the upshot I have yet to see a burnt-up one of these saws.

Click to expand...

Yep, My one 288, would just "burble" at WOT no matter what. It settles down in the cut, but just never had the revs that sounded right.....10500 is kinda low at WOT in my opinion for those saws. I'm still waiting for my tach, so I actually know where I'm at when I'm tuning.

The timeing on this thread is just right.

A year agoe a friend of mine got a 288XP, someone was fed up with it and sold it to him for a little of nothing. We spent a little time with it and tried to figure it out, but got fed up with it after bit and put it aside untill a few days agoe. It will run like a scalded dog......for 4 or 5 seconds, then it just dies out. We went through the carb and same story. Tank vent, gas line, filter, all good or new. Crankcase vac check, fine.

I bought the saw 2 days agoe for a project and tore it apart, it passes a vac check but the crank seals are pretty hard and dry. The ignition switch is junk, the wires are rubbed bare in a few places. So in about a week I'll have my parts order of leds, seals, etc and hopefully put it back togather ASAP. I was wondering what that big brass plug was, now there's a better chance of getting it running right.

My compression gauge is pretty honest, I never seam to get these high numbers that some claim. This old Husky will blow 160 PSI, and when I checked the squish, .042 so I checked again and got the same measurement. It's going to run good with a proper carb, .020 squish, opened up exhaust port and muffler.

Brmorgan
I took a look at my carb and it does not have the brass screw (If I am looking at it correctly). It isn't on the outside at least. I went ahead and pulled the carb apart and there is a brass screw next to the needle valve it has the number 72 stamped on it and a tiny hole in the center. I pulled up the diagram from the tilloston page and have the shop manual for this saw but they are not the same as my carb. Do you think this could be it? This carb doesn't have a impulse hose either? Good thing I discovere I guess, The shop installed the diaphrams and gaskets in the wrong order.

My carb is an HS 283 by the way. There is an HS on the side of the carb and the number 283B040. Maybe this will help if any of you have a diagram.

Where is the tank vent located? I am guessing it is the tiny hole on the side of the tank where you fill located which should be towards the top of the tank.

Another question if you remove the wire coming from the ignition module and going to the kill switch and use an ohm meter to go between that wire and the frame of the saw should it ohm out (show a short)?
thanks

Forgot to add that when I pulled the jet screws I looked at them and the seats under magnification and they looked great the Hi Jet screw was missing the little rubber washer that goes between the spring and the body of the carb.

Just in case, here's a pic of the governor screw on my Pioneer P41 carb (same carb basically) that I posted in the Pioneer thread a while ago:



It's the brass screw you can see on the right-hand side. I know it isn't a great pic but I'll try to get one of an actual 288 carb tonight.

Here's the screw itself after being removed from the carb body:



You can see the inlet hole in the side of the screw and the outlet in the bottom.

tmroper said:

My carb is an HS 283 by the way. There is an HS on the side of the carb and the number 283B040. Maybe this will help if any of you have a diagram.

Click to expand...

I just ended up with a 288xp lite yesterday and it has the same carb as yours.......Definitely no governor on that carb!!

tmroper said:

Forgot to add that when I pulled the jet screws I looked at them and the seats under magnification and they looked great the Hi Jet screw was missing the little rubber washer that goes between the spring and the body of the carb.

Click to expand...

Just to say Thank you for purchasing the RK23 HS kit from me it went out yesterday first class mail you should be getting it any day

Hi Guys,
Just a little update. I got the carb kit ordered from Mowertech (He was really great to deal with and I will be glad to do business with him in the future. Thanks Mowertech). I haven't gotten the kit yet but it could be at the post office. I live in a pretty rural area and usually only go to my mailbox once every two weeks but am going to make a trip tomorrow due to being anxious to give it a go.

I got a little anxious waiting so I went a head and pulled apart the saw as I mentioned was fully rebuilt by a shop and found that the had installed both of the diaphrams and gaskets on top and bottom in the wrong order.:jawdrop: and the gasket that goes between the Cylinder and intake tube (not sure of proper name for this tube that goes between cylinder and carb) slipped down when installing and caused an air leak along w/ blocking flow. I didn't order this gasket so I will have to pick up one.

I tell you guys I do all my own wrench turning on everything on the ranch and this was the first thing I have ever taken in to the shop and have not been to impressed. Now before someone reads this wrong whether you are a saw owner or the owner of a shop I am not talking about all shops because they are not equal. I have never taken anything in because of not having the funds but never have worked on a saw I figure it would be the simpler route. I would just take the advice of others if I were buying new or getting a rebuild w/ a warranty and choose a shop based on the service you will recieve. I sure hope this is the problem it certainly didn't help.

Jockeydeuce congrats on your new saw.
Brmorgan and all the rest of youthanks for all your info it will be stored for later use and was something that I did not know.

I will let you guys know how this turns out. I have been reading other posts for fun and for some reason it always bums me out when they don't say what the cure was.
Thanks everyone