Check if you put the kit in the proper order and rule that out first. I've done that myself.
New to me, Dayton 2Z463
- Thread starter Bobby Kirbos
- Start date
Help Support Arborist Forum:
Should die completely with the L screwed all the way in.
Why you're inside the HS59 carb there, check that the main nozzles’ check valve reseats, that a Welch plug is not leaking by, and that your metering lever was not set too high (needs lowered).
Why you're inside the HS59 carb there, check that the main nozzles’ check valve reseats, that a Welch plug is not leaking by, and that your metering lever was not set too high (needs lowered).
Bobby Kirbos
Scrounger of Cellulose Based BTUs
I know I put things together in the correct order (assume you're talking about the assembly order of the gasket, diaphram, and cover). I did have a welch plug that I wasn't sure about, so this may be why it idles with the idle screw completely closed off. I also think the metering lever is set too high. It does sit above the carb body. I found the Tillotson service manual for the HS series and the lever is supposed to sit flush with the body.
I'll get another repair kit and redo the metering side including the welch plugs. The pump side obviously works.
I'll get another repair kit and redo the metering side including the welch plugs. The pump side obviously works.
BTW, which piston, circlips, & rings did you end up putting in the saw, the OEM or little red barn?
Bobby Kirbos
Scrounger of Cellulose Based BTUs
OEM from @Acornhill.
Bobby Kirbos
Scrounger of Cellulose Based BTUs
Carb kit should be here tomorrow, so I will have the carb out to revisit the metering side.
I have discovered that this carb has a governor (rev limiter) built into it. Somehow, it uses the vibration of the saw to control it. The governor dumps fuel forcing the mixture rich, making the saw 4-stroke, keeping the revs down. I wonder if THIS could be part of my flooding problem (the governor might be be stuck open, dumping fuel -- that would certainly explain why the saw idles with the low needle completely closed).
I have found threads where people have easily defeated the governor. As long as I have the carb out --- That is, if it were you, would you defeat this governor?
I have discovered that this carb has a governor (rev limiter) built into it. Somehow, it uses the vibration of the saw to control it. The governor dumps fuel forcing the mixture rich, making the saw 4-stroke, keeping the revs down. I wonder if THIS could be part of my flooding problem (the governor might be be stuck open, dumping fuel -- that would certainly explain why the saw idles with the low needle completely closed).
I have found threads where people have easily defeated the governor. As long as I have the carb out --- That is, if it were you, would you defeat this governor?
Google ‘Tillotson HS’, open the HS Service Manual pdf, and study the idle circuit in color. The check valve in the main nozzle is closed when idling (if it’s working correctly), so no it will not cause that rich idling problem that you’re having.
Post #22 covered three common causes.
You can always plug your governor, if you’ll listen for the 4 stroking exhaust tone at no load out of the cut...but it’s cheap insurance from over revving if you loan the saw out!
Those HS carbs are bulletproof, and one of the easiest to troubleshoot & work on.
If you plan to use the saw, you also need to take the top/handle off and replace the foam body gasket that has disintegrated, and I would also pressure & vacuum test the engine for any air leaks.
Post #22 covered three common causes.
You can always plug your governor, if you’ll listen for the 4 stroking exhaust tone at no load out of the cut...but it’s cheap insurance from over revving if you loan the saw out!
Those HS carbs are bulletproof, and one of the easiest to troubleshoot & work on.
If you plan to use the saw, you also need to take the top/handle off and replace the foam body gasket that has disintegrated, and I would also pressure & vacuum test the engine for any air leaks.
Bobby Kirbos
Scrounger of Cellulose Based BTUs
Found the service manual. I think I see where my problem may be.
Disassembly instructions:
The fact that the diaphragm needs to be "unhooked" from the lever tells me that there is a reverse step on the assembly end. I didn't slide the diaphragm into the metering lever. I simply put the diaphragm on top and screwed the thing closed. So, my bet is that the inlet needle is being held wide open.
Looking at the color operation diagrams, I think:
That would explain both why it idles with the low screw fully closed, and why it runs like a raped ape when I open up the throttle.
Thoughts?
Disassembly instructions:
The fact that the diaphragm needs to be "unhooked" from the lever tells me that there is a reverse step on the assembly end. I didn't slide the diaphragm into the metering lever. I simply put the diaphragm on top and screwed the thing closed. So, my bet is that the inlet needle is being held wide open.
Looking at the color operation diagrams, I think:
- fuel pump is pushing fuel through the carb - a ton of it with nothing to stop it
- without having the inlet needle to control how much fuel gets to the bottom
- at idle, fuel is being forced (by the pump) through the high needle but the air flow is closed off down stream of the needle, so it's flooding.
That would explain both why it idles with the low screw fully closed, and why it runs like a raped ape when I open up the throttle.
Thoughts?
No doubt!, but probably would not run all. There are two different metering diaphragms used on the HSs, one with a slotted nub & one just flat. If you used a kit, the lever & nub are matched.
The crankcase will fill completely up with raw fuel in no time, or if it’s tilted backwards it will run out into the carb box.
Good thing you didn’t set it by the hot water heater!
The crankcase will fill completely up with raw fuel in no time, or if it’s tilted backwards it will run out into the carb box.
Good thing you didn’t set it by the hot water heater!
Bobby Kirbos
Scrounger of Cellulose Based BTUs
As described in post #28 was EXACTLY the problem.
I took the metering side of the carb apart this evening. During disassembly, the diaphragm lifted right off without needing to "unhook" it from the metering lever. The metering lever was also set too high. Armed with the knowledge from the service manual, I set the metering lever height and reassembled the carb - this time making sure to get the little "hook" into its proper position. I set the needles to their default position as described in the manual (L -- 1 turn, H -- 1-1/2 turn) and cranked it. 4 pulls and he popped. Choke off, 2 pulls and off he went. I tweaked the low needle just a touch (it was too rich). The saw was very responsive to small changes in the needle position. The high needle I will need to adjust in wood. The saw sat and idled for about 5 minutes without missing a beat. When I gunned it, the throttle response was superb. The fuel delivery problem is fixed.
Another problem that I fixed this evening was the timing. As stated earlier in this thread, I removed the antiquated points and condenser, and replaced them with an Oregon solid state ignition module. The other day when the saw popped, it almost ripped the starter rope out of my hand. The timing was too early. Searching around, I found that others had the same problem, and the solution was to move the coil closer to the fly wheel. I had the coil and flywheel gapped with a business card (0.013"). I reduced the gap to 0.008" (thickness of 2 sheets of 20# office paper). Ignition timing is much better. It doesn't rip my arm off when it pops. I don't know if it's ideal, but I'll leave it where it is unless I find some reason to change it.
AND NOW, THE THANK YOUS
Thank you to everyone on this board for all of your help, not only with this saw, but in my other chainsaw questions. You guys posses a wealth of information and are more than willing to share it. I have learned a TON of chainsaw and small engine stuff from this site. Could I have done this rebuild without the knowledge found here, probably. Would I have invented some new 4 letter words in the process, absolutely. Just knowing that I could "ask the guys on the board" was comforting. So again, thank you to all of you.
@farmer steve - Thank you for the "donor" Dayton saw. While not the same model, I was able to use a couple of the parts and some screws from it (including the low screw on the carb since I broke the one on my saw
).
@Acornhill - Thank you for the advice and the model specific parts that I needed. Yes, there were cheaper options on eBay at the time, but from you I knew that I was getting the exact parts that I needed.
Pictures and video will follow at some time in the (hopefully) near future.
I took the metering side of the carb apart this evening. During disassembly, the diaphragm lifted right off without needing to "unhook" it from the metering lever. The metering lever was also set too high. Armed with the knowledge from the service manual, I set the metering lever height and reassembled the carb - this time making sure to get the little "hook" into its proper position. I set the needles to their default position as described in the manual (L -- 1 turn, H -- 1-1/2 turn) and cranked it. 4 pulls and he popped. Choke off, 2 pulls and off he went. I tweaked the low needle just a touch (it was too rich). The saw was very responsive to small changes in the needle position. The high needle I will need to adjust in wood. The saw sat and idled for about 5 minutes without missing a beat. When I gunned it, the throttle response was superb. The fuel delivery problem is fixed.
Another problem that I fixed this evening was the timing. As stated earlier in this thread, I removed the antiquated points and condenser, and replaced them with an Oregon solid state ignition module. The other day when the saw popped, it almost ripped the starter rope out of my hand. The timing was too early. Searching around, I found that others had the same problem, and the solution was to move the coil closer to the fly wheel. I had the coil and flywheel gapped with a business card (0.013"). I reduced the gap to 0.008" (thickness of 2 sheets of 20# office paper). Ignition timing is much better. It doesn't rip my arm off when it pops. I don't know if it's ideal, but I'll leave it where it is unless I find some reason to change it.
AND NOW, THE THANK YOUS
Thank you to everyone on this board for all of your help, not only with this saw, but in my other chainsaw questions. You guys posses a wealth of information and are more than willing to share it. I have learned a TON of chainsaw and small engine stuff from this site. Could I have done this rebuild without the knowledge found here, probably. Would I have invented some new 4 letter words in the process, absolutely. Just knowing that I could "ask the guys on the board" was comforting. So again, thank you to all of you.
@farmer steve - Thank you for the "donor" Dayton saw. While not the same model, I was able to use a couple of the parts and some screws from it (including the low screw on the carb since I broke the one on my saw
).@Acornhill - Thank you for the advice and the model specific parts that I needed. Yes, there were cheaper options on eBay at the time, but from you I knew that I was getting the exact parts that I needed.
Pictures and video will follow at some time in the (hopefully) near future.
Bobby Kirbos
Scrounger of Cellulose Based BTUs
The bar came in yesterday and I got a couple of loops for it this morning.
That is one sexy machine.
That is one sexy machine.
Good job on the rebuild.
Did you install a new body gasket as mentioned in post #27? A Briggs & Stratton foam air filter can be sliced up & used for the gasketing.
If you actually use that saw to cut wood, the air box, carb & crankcase will be full of dirt in no time.
Did you install a new body gasket as mentioned in post #27? A Briggs & Stratton foam air filter can be sliced up & used for the gasketing.
If you actually use that saw to cut wood, the air box, carb & crankcase will be full of dirt in no time.
Bobby Kirbos
Scrounger of Cellulose Based BTUs
I was aware that I needed something there, but I didn't use a foam gasket. I ended up putting down a heavy bead of Permatex #2 between the crank case and the fuel tank/handle assembly before I put the parts together. It's not factory original, but it gets the job done.
Camdo
ArboristSite Lurker
Great write up Bobby.
I would also like to put a big bar on my Dayton 2Z463 (Poulan 245 SA) for occasional use.
Did you go with a skip tooth chain on your 28 inch bar?
Are you happy with the cutting action of the saw/bar/chain combination?
I noticed Oregon sells a 32 inch bar with an adapter that will fit the saw. Given your experience with the 28 inch bar, do you think 32 inch is too much, or worth a try?
Bobby Kirbos
Scrounger of Cellulose Based BTUs
I'm running full comp and it pulls quite well. This saw is in no way a speed demon; it's a torque generator, so it will pull, and pull, and pull - until it runs out of gas.
28" is nominal. By the time the bar mount takes its needed length, the usable bar length is closer to 27". I have spikes on mine and I lose a bit there, so my overall usable bar length is about 26-1/2". I can't see where I could possibly ever need more than 52" of bar (26" from each side).
As for a 32" bar, I would definitely run a full skip on that. Not just to moderate the power load, but also for chip clearing. The 28" already balances front heavy. A 32" would be REALLY front heavy.
Personally, yeah, I think a 32" bar is too much. Worth a try? If you've got $$ burning a hole in your wallet and feel like it, go for it (and go full skip).
Camdo
ArboristSite Lurker
Thanks for the feedback Bobby. I did not consider balance. Will a skip tooth chain cut faster with less power? I have never used one but I know a metal cutting bandsaw with a skip tooth blade will cut much faster with seemingly less power.
My Poulans:
Dayton 2Z463 20" bar with compression release and power sharp (my favorite)
Poulan 245A 20" bar
Poulan 306A 16" bar
Dayton 2Z971 16" bar
Bobby Kirbos
Scrounger of Cellulose Based BTUs
A skip chain has 2/3 the amount of cutters compared to a full comp chain - 2/3 of the load on the engine so you need less power to pull it. Like everything real life, the power curve is not linear, so 2/3 of the load may equate to 1/2 of the power required, so it could very likely be faster. I don't know the squiggly math behind it, sorry.
cre73
Always Lurking, never posting
Great job on the saw turned out very nice.
Please explain the foam thingy.
Camdo
ArboristSite Lurker
"If you actually use that saw to cut wood, the air box, carb & crankcase will be full of dirt in no time".
My saws fill up with chips because the small bellows that seals the throttle linkage entering the air box is split or otherwise open to outside elements from material decomposition. A genuine replacement bellows seems impossible to get. Does anyone know of a solution or substitute part?
My saws fill up with chips because the small bellows that seals the throttle linkage entering the air box is split or otherwise open to outside elements from material decomposition. A genuine replacement bellows seems impossible to get. Does anyone know of a solution or substitute part?
Similar threads
- Locked
