diezelsmoke
ArboristSite Operative
I use a fine file works good, you can see what material you are removing, use a wire wheel to clean out the ring land.
Huskie 55 Closed Port Piston
- Thread starter cedarshark
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cedarshark
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I ran across a thread from "rynosaur" to fix this intake with a threaded 5mm bolt and threaded nut inserts rather than use the OEM self tapping carb screws. Looks like a very good fix for the the design problem for the 55 intake issue.
While its good to fix the piss poor carb bolts this damage was caused by not letting the saw warm up enough. Steve
I agree with those who would use that piston with a new set of rings...and also judging from the fact it seems to be more about surrounding a transfer port than being more uniformly across either the exhaust (most usual with heat) or intake (lube issues), that seems to signal debris of some sort hurt that saw or possibly a cold seize. Maybe a bearing cage, or something being sucked in from out side? Was the air filter ripped? Had you already cleaned up that piston? Was there aluminum transfer on the cylinder? If there was no aluminum left on the cylinder, just scratches that also points to debris or cold seize, something that happened quick.
Finnrpm
ArboristSite Operative
Was the piston cleaned after removal, or did it look like that when you removed it? To me it has marks of a piston stop being used........ Also i would take a good look for the crank bearing while it is without cylinder.
I have a 51 ( non epa ) and it has developed running issues, goes lean after a while on wot, impulse line or fuel line or .......
If it comes to replacing the cylinder and/or piston i will be checking these:
http://www.hlsproparts.com/Husqvarna-55-55-Rancher-windowed-piston-kit-p/h31055-w.htm
and
http://www.hlsproparts.com/Husqvarna-55-51-cylinder-and-piston-assembly-p/h30055-w.htm
RV
I have a 51 ( non epa ) and it has developed running issues, goes lean after a while on wot, impulse line or fuel line or .......
If it comes to replacing the cylinder and/or piston i will be checking these:
http://www.hlsproparts.com/Husqvarna-55-55-Rancher-windowed-piston-kit-p/h31055-w.htm
and
http://www.hlsproparts.com/Husqvarna-55-51-cylinder-and-piston-assembly-p/h30055-w.htm
RV
cedarshark
Addicted to ArboristSite
The air filter/muffler/carb screws were missing when I bought the saw. It supposedly was purchased from a dealer going out of business and prob was robbed for some parts. The ring was stuck in the groove when I pulled the piston and yes, it was cleaned up on a wire wheel to get the carbon off the top of the piston. There is minimal transfer of aluminum on the cylinder. It will clean up well with no scratches. The more you guys commment after looking at the piston, the more I believe the evidence points toward a cold seize or debris inhaled. I will clean the cylinder and piston later today w/ my foredom and a 400 grit flapper wheel and post pics of both. The bearings appear to be fine with no rough spots or debris in the bottom of the crankcase.
cedarshark
Addicted to ArboristSite
I have a Huskie 353 with a Hyway top end and it runs fine. This Hyway piston is 46mm and will not fit the 45mm OEM Mahle cylinder. You may want to check your intake on the 51. They are prone to leak at the intake boot at either the cylinder side or partition side.
The 55 closed port cylinder is 45mm, and the transfer port design is better than the current aftermarket options.
Something you want to keep if possible...
cedarshark
Addicted to ArboristSite
On a side note, I noted the base gasket on this 55 is very thin plastic. I have never seen a base gasket made from plastic before. Is this common with this series saw ? The gasket stuck to the case when I pulled the piston. I will pull it later today and post a pic for you to look at.
cedarshark
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I agree and if I cannot salvage the OEM piston, I may just put the project on temp hold until I can find an OEM piston. The remainder of the saw is in very good condition and is worth being patient if necessary.
Finnrpm
ArboristSite Operative
Got new parts ( intake side ) on the way. Is adding small amount of sealant to the intakeboot wise?
Will remenber this, thanks!
RV
cedarshark
Addicted to ArboristSite
The intake boot is a "slip fit" on either side and depends on friction to stay sealed. To compound the problem, the screws that hold the carb assembly to the cylinder are self tapping and will tend to loosen over time causing an air leak because you cannot tighten the screws sufficiently w/o stripping the threads. Some people have posted that they can be sealed w/ grease. Good question about using a good sealant. Most people think the intake boot should be replaced every time it is removed and sometimes even the partition so you are not re-using the old threads in the plastic.
+1 on reusing the piston. I've reused worse than that on my saws. Just be forthcoming to potential buyers. I purchased a 49sp on here with a scored/reused piston. It still runs great.
Adding a little bit of sealant won't hurt, but it needs to be something that stays flexible and I wouldn't apply very much... it will effectively become like a grease to help the pieces slip together, as the intake boot/sleeve is usually very tight and can be tough.
I would not use sealant on the intake grommet for fear of blocking the impulse hole, just some light grease or oil.
cedarshark
Addicted to ArboristSite
Here is the piston after some cleaning with a Dremel and a 400 grit flapper disc. I believe it turned out ok and will be usable. My Foredom does not have a speed control and spins too fast for the control I needed.
cedarshark
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Pic of some of the parts to give you an idea what shape the saw is in. The base gasket is paper...not plastic. I have no idea if a new one can be bought, so I just made a new one from thin gasket paper. I will remove the decomp valve as it is not necessary on a 51cc saw.
cedarshark
Addicted to ArboristSite
Cylinder cleaned up well with no aluminum transfer and no scratches. Done w/ the Foredom and a 200 grit flapper disc, then finished w/ wet/dry 400 grit sandpaper.
If you hog out the lower transfers right through the bottom skirt to match the case (and where you also already cut them into the base gasket), you can use a 353 or 51 piston to good effect...
One of my 55 closed port saws had the piston scored worse than that one. I cleaned up the piston, cylinder and ring and put it right back in service. It has over 150psi compression now for nearly 10 years and runs flawlessly.
The important thing here is that the bore is not torn up with long/deep grooves the entire distance, and that the ring is in good shape and fits tight but moves freely in the groove. The piston skirt really doesn't matter if it has vertical scoring, as long as it fits tight in the bore......Cliff
The important thing here is that the bore is not torn up with long/deep grooves the entire distance, and that the ring is in good shape and fits tight but moves freely in the groove. The piston skirt really doesn't matter if it has vertical scoring, as long as it fits tight in the bore......Cliff
cedarshark
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I appreciate all the help guys. Without your input, I would probably have waited forever looking for an OEM windowed piston.
