Husky 55 EPA carb number of turns

[hangfirew8]

Basic question is, how many turns out on a ZAMA C1Q-EL7 H&L to start tuning a 1998 Husqvarna "EPA". Saw starts with choke on and runs only with the choke feathered around half and then cuts out. Don't want to push it any further for fear of running it lean for too long.

The background...

I picked up an at a flea market for $50 a week ago. PO said it ran (yeah, right) and warned it was leaky and "just" needed a new fuel line (yeah, right). Too difficult to pull without engaging the compression release. New chain, well used bar with some life left in it, most of the saw utterly packed with oiled sawdust, airbox only a light film of dusty slime, semi-clogged air filter. I pulled it down and viewed piston from both sides, still unscuffed and covered with original machining marks, cylinder looks perfect from all 3 views. Top of piston looks like it was run rich for a while before I got it.

Cleaned it up. Everything looks like it's in really good shape, especially for a '98. Put a new Tygon and fuel filter on it (that was easy! compared to some other saws I've worked on). Then it would cough and pop a bit but was wet beyond imagination in the chamber, it was choking out. Had to pull the plug and let it air out just to get it to cough again. No gas anywhere else, it was the carb leaking.

So I got the Oregon 49-438 rebuild kit, pulled apart the carb and soaked it a while and put it all back together. Once I pulled enough to get gas sucked up into the carb (there's no primer bulb), it fired right up, but it won't run without about 1/2 choke and even then after 30 sec or a minute it dies. I can see fuel coming through the Tygon line so it's not fuel supply. Brand new plug is dry and so is chamber so the excessive rich condition seems to be fixed but now I'm worried it's running lean.

When I rebuilt the carb, only parts left over were a screen and the triangular foil. Try as I might I could not get the old foil off. Not sure if any of that matters.

Thanks for any help! I've been away from this site except for some occassional lurking and reading. I love chainsaws, but sometimes life intervenes. I've been rocking a little Husqvarna 435 that has met all my modest needs for the past several years. I've always wanted a decent 50 cube saw and I'm hoping this is it. Some of my trees are getting beyond mature and a few are threatening the house and neighbor's fence and have to come down soon. It would be nice to use the 55 if possible.

 

[RanchDad]

Basic question is, how many turns out on a ZAMA C1Q-EL7 H&L to start tuning a 1998 Husqvarna "EPA". Saw starts with choke on and runs only with the choke feathered around half and then cuts out. Don't want to push it any further for fear of running it lean for too long.

The background...

I picked up an at a flea market for $50 a week ago. PO said it ran (yeah, right) and warned it was leaky and "just" needed a new fuel line (yeah, right). Too difficult to pull without engaging the compression release. New chain, well used bar with some life left in it, most of the saw utterly packed with oiled sawdust, airbox only a light film of dusty slime, semi-clogged air filter. I pulled it down and viewed piston from both sides, still unscuffed and covered with original machining marks, cylinder looks perfect from all 3 views. Top of piston looks like it was run rich for a while before I got it.

Cleaned it up. Everything looks like it's in really good shape, especially for a '98. Put a new Tygon and fuel filter on it (that was easy! compared to some other saws I've worked on). Then it would cough and pop a bit but was wet beyond imagination in the chamber, it was choking out. Had to pull the plug and let it air out just to get it to cough again. No gas anywhere else, it was the carb leaking.

So I got the Oregon 49-438 rebuild kit, pulled apart the carb and soaked it a while and put it all back together. Once I pulled enough to get gas sucked up into the carb (there's no primer bulb), it fired right up, but it won't run without about 1/2 choke and even then after 30 sec or a minute it dies. I can see fuel coming through the Tygon line so it's not fuel supply. Brand new plug is dry and so is chamber so the excessive rich condition seems to be fixed but now I'm worried it's running lean.

When I rebuilt the carb, only parts left over were a screen and the triangular foil. Try as I might I could not get the old foil off. Not sure if any of that matters.

Thanks for any help! I've been away from this site except for some occassional lurking and reading. I love chainsaws, but sometimes life intervenes. I've been rocking a little Husqvarna 435 that has met all my modest needs for the past several years. I've always wanted a decent 50 cube saw and I'm hoping this is it. Some of my trees are getting beyond mature and a few are threatening the house and neighbor's fence and have to come down soon. It would be nice to use the 55 if possible.

Best info I’ve seen says 1.25 turns out on both the Hi and Low is a good starting point


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[happysaws]

There is a chance that the metering lever height is not adjusted correctly. Take the carb back off and pry up on the metering lever a very little bit.

 

[cus_deluxe]

Did you mangle the "foil" (welch plug) at all? If so you could prob mess with carb screws all u want and not get a good tune. That thingy has to seal tight or else you'll have issues. If it wont start and run reasonably well at 1-1.25 turns out u have other issues.

 

[hangfirew8]

Best info I’ve seen says 1.25 turns out on both the Hi and Low is a good starting point

Thanks, 1-1/4 is where I put it when re-assembling.

There is a chance that the metering lever height is not adjusted correctly. Take the carb back off and pry up on the metering lever a very little bit.

OK I can do that.

Did you mangle the "foil" (welch plug) at all? If so you could prob mess with carb screws all u want and not get a good tune. That thingy has to seal tight or else you'll have issues. If it wont start and run reasonably well at 1-1.25 turns out u have other issues.

Yes I smashed it real good, don't know if it's sealing around the edges any more or not. Since I'm pulling off the carb again (not a big deal on this model) I'll have another go at replacing it.

Thanks everyone, I'll keep at it until I get this thing in shape!

 

[happysaws]

...
Thanks everyone, I'll keep at it until I get this thing in shape!

That is a very good attitude to have.

Ideally you want the metering lever to be flush with the carb body, or bosses, if the carb has any.
Use a flat edge to check the level, you want the flat edge to just touch both the metering lever and carb body/bosses.

 

[PogoInTheWoods]

A vac/pressure test will probably reveal an intake air leak on that saw. Hence the need for the extra choking to stay running. They're notorious for the impulse tube and/or intake sleeve losing their seal to the bulkhead over time. The carb screws are also known for easily stripping out the nylon threads if cross-threaded or ham fisted. All easy fixes on a very worthy saw.

 

[hangfirew8]

That is a very good attitude to have.

Thanks... or... I'll keep going until I run out of money, or cost of parts exceeds saw value, lol....

So, excited I have something concrete to try, I just replaced the welch plug and bent the metering lever up a little. I think it's just barely above level as you described it. Anyway, the saw seemed to notice, I could run it longer by feathering the choke, but eventually it would crap out.

Trying to think of what to do next, I got out my nice new compression test and tested with the comp relief not engaged. It's a b**** to pull like that, but I got to a hair above 145, call it 146 PSI. So once again everything about this saw seems to check out well but the carb. I just don't have much luck with these little tiny carbs. I used to rebuild auto carbs years ago with a 100% success rate. I think I'm at about 20% with tiny OPE carbs, with this one on the wrong side of that batting average.

Maybe I set the new triangular welch plug a little too hard. Or maybe it's still wonky in the passages. Previously I did pull off the carb middle plate and the rubber intake manifold sleeve was still pliable and seemed to seal well.

This option is looking better and better:
https://www.amazon.com/C1Q-EL7-Zama-Carburetor-Husqvarna-Chainsaw/dp/B00ISRI3GU

I've got $12 into the carb rebuild kit, a new carb would make it a $107 saw, still a good deal I think, considering the newish condition of the internals on this saw.

Thoughts? I really appreciate the help on this board. Here's a pic:


Thoughts?

 

[hangfirew8]

A vac/pressure test will probably reveal an intake air leak on that saw. Hence the need for the extra choking to stay running. They're notorious for the impulse tube and/or intake sleeve losing their seal to the bulkhead over time. The carb screws are also known for easily stripping out the nylon threads if cross-threaded or ham fisted. All easy fixes on a very worthy saw.

Well, that just happened. Left side screw just stripped out. It still has a bit of grip. The left side has the bottom bolt on the carb plate which helps hold the carb secure, and I put a little gasket silicone on both sides of the paper gasket, being careful not the block the impulse hole.

What's the best fix for this? Drill out that side and fill it with something? A bushing or some kind of epoxy or something? I'm not afraid to drill and tap steel so working plastic doesn't scare me, but I'm not sure what to use to fill it with. I don't suppose that chunk of plastic is still available?

I checked out the intake before, as I noted above (your answer wasn't up yet when I typed in mine). Seems to me if the impulse tube was leaky or blocked it wouldn't draw gas at all. Or maybe it's not drawing enough. That would make sense for my situation. I can check that out, but maybe not tonight. It's getting late and I don't want to go to bed smelling like gas, or piss of the neighbors starting the saw.... LOL.

I think I'm REALLY close. Don't want to drop near $50 if I can fix it as-is.

 

[PogoInTheWoods]

Double check the impulse tube connection to make sure the rubber sleeve in the cylinder base it isn't pinched or jammed sideways by the tube coming from the bulkhead.

 

[hangfirew8]

Double check the impulse tube connection to make sure the rubber sleeve in the cylinder base it isn't pinched or jammed sideways by the tube coming from the bulkhead.

OK That's the next thing I will do... but while I have it that far apart, I'd like to fix the freshly stripped hole in the bulkhead. Any advice there?

 

[PogoInTheWoods]

FWIW, a nice 55 will bring $200 all day long in my area. If you intend on keeping the saw, you have a way to go before the point of diminishing returns and will be quite happy when you get it running right. Great little saws.

I've used heli-coils for those stripped threads and they worked fine. I believe I went 5mm and replaced the self-tapping screws with cap screws. The bulkhead itself should also be available cheap on eBay, chainsawr, or any number of places.

 

[hangfirew8]

Thanks, Pogo. I have some options now. I'll update this thread once I have time to make more progress. I do intend to keep it. I can go higher on the investment if I can sell the $5 Poulan Pro in my sig. It just needs "a little more work" (haha).

 

[dougand3]

I fixed the bulkhead like rynosawr shows here: Worked well.

https://www.arboristsite.com/commun...on-with-stripped-threads.298076/#post-5894682

 

[PogoInTheWoods]

That's another good fix.

 

[hangfirew8]

Great minds think alike. I was checking out the bulkhead (couldn't resist one more try at it tonight) and thought "Hmm I could just drill the back and glue a nut in there." I'll do something like that. I don't have a Helicoil near small enough or I'd use one.

Impulse tube that extends from bulkhead was clear. I had already checked that. It seats in a rubber sleeve which seems to seal well. I removed the little sleeve and it's still pliable. I tested vacuum at the port and got some good sharp pulses. I'm calling the impulse pathway good.

While I was pulling, the pull starter locked up. Afraid I dropped something in the piston, I took the side off but then everything turned easily, the pull start and the flywheel both (with plug removed). So I put the side back on, and after one pull it locked up again. Must be the floppy lever starter thingies (pawls? Or things that engage the pawls?) Anyway I think that's an easy clean and lube fix. But I'm done for tonight.

Thanks again everyone! I'll pick it up again in a few days. Busy schedule this week.

 

[hangfirew8]

 

[hangfirew8]

 

[PogoInTheWoods]

It idles (too high) and certainly looks like it oils!

Good to see it running.

 

[hangfirew8]

Thanks Pogo and everyone! I got the OEM Carb on eBay and a new bulkhead, and it fired right up.

I'll bring the idle down a little more. I cut a bit of wood but had to stop as it was getting dark. Rakers need to come down a little but saw feels strong!

I'm into it for $100 plus $12 of air filters (no one counts consumables, right?). I'm a happy camper!

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