Husqvarna 55 closed port

[radio]

One thing I would do if I did another would be to replace both of the rubber pieces on either side of the oiler and a fresh bar pad. I think it's less than $10.00 worth of stuff and the oil pump only moves 9 mL/min when new. These items help to make sure it works at it's fullest potential. Lots of research and some old posts on Aroborist Site by Rupedoggy shared that info.

+1

I replaced these same items last year on one of mine - oil pickup $13 at dealer, oil pump seal $4 at dealer, and aftermarket inner bar plate $5 at HL Supply.

 

[kyle.kipple]

Well speak of the devil ... I just noticed HL Supply has the 46mm CP top end linked above on sale today for $53.32 !!!

@kyle.kipple - At this price and based on Jimmy in NC's experience I would think that you couldn't go wrong giving this one a try.

Good looking out! I have one on the way. Thanks mister!

One thing I would do if I did another would be to replace both of the rubber pieces on either side of the oiler and a fresh bar pad. I think it's less than $10.00 worth of stuff and the oil pump only moves 9 mL/min when new. These items help to make sure it works at it's fullest potential. Lots of research and some old posts on Aroborist Site by Rupedoggy shared that info.

Now before everyone flips out... that 9 mL/min is constant.. even when idling a 51/55 keeps oiling as opposed to a clutch drum driven oiler. When you stop cutting to move to the next spot or saw is idling while you scratch you rear, it's oiling. Due to that, 9 mL/min is enough oil. When the rubber bits get older and the bar pad deforms, the little pump starts sucking air, oil seeps other places, etc and it is not efficient.

*Ok I just looked and the pickup is ~10.00 new OEM now.. still, in my opinion, if you are building a saw, do it up proper. A sharp chain is no good with out enough oil on it.

Appreciate your input and will check everything out once I have it running again.

 

[kyle.kipple]

Order my kit Friday and received it Monday. Fast shipping! However I believe I'll be sending this one back. There's a casting flaw by the transfer that I do not care for. Would it be ok to run...probably. But I called Chris and sent him some photos. He will be getting with me tomorrow about returning the part and them getting me a new kit. Really thorough and great guy to deal with. Didn't beat around the bush at all about anything. That's customer support!!

 

[Wolverine]

Ewww, that's fugly!

 

[RIDE-RED 350r]

I would definitely seek a replacement for that cylinder. Good move on your part.

 

[paragonbuilder]

I'm willing to bet, that without machine work and porting the AM CP jug, that the oem open port would outperform it.
If I remember correctly, even with gasket deleted they have a huge squish. And as you can see they really need some cleaning up.
I don't think you will get a true feel for what the oem CP jug was like with this AM jug.

 

[paragonbuilder]

That is not to say that it won't run well, just not like they do stock.

 

[cus_deluxe]

Not the same exactly, but i put an am 46 mm open port kit on an old 51 i had. With base gasket squish was almost .070!

 

[Motorhead]

Oem open port 46mm with gasket delete is 21, 22 thousandths on three saws, 2 50s and a 55.I have a 51 with a 45 mm oem open port cylinder, that had 40 thousandths before I cut the base.

 

[Wolverine]

The OP 55 Andrew did was .0335 without base gasket.



Closed port cylinder had .030 squish with the base gasket delete.

 

[kyle.kipple]

I would definitely seek a replacement for that cylinder. Good move on your part.

New cylinder is on its way. HL has great people to deal with.

I'm willing to bet, that without machine work and porting the AM CP jug, that the oem open port would outperform it.
If I remember correctly, even with gasket deleted they have a huge squish. And as you can see they really need some cleaning up.
I don't think you will get a true feel for what the oem CP jug was like with this AM jug.

I will check the measurements when I throw it together. Might be late next week before I get to it. I pulled the mud buggy tracker in to swap the motor and fix a few things before trail riding starts soon. My priorities are jacked!

 

[DigB]

Not the same exactly, but i put an am 46 mm open port kit on an old 51 i had. With base gasket squish was almost .070!

I just mounted a Hiway closed port 55 and the squish is .0054 inches! without the gasket!

In addition, the mounting holes were ever-so-slightly too close to allow all four screws to engage simultaneously, so it required a little reaming.

This is an older kit, from the time I first became aware of them about a year-and-a-half ago, so maybe this has been corrected. I am putting this cylinder aside until I can have it decked.

 

[David Young]

I just mounted a Hiway closed port 55 and the squish is .0054 inches! without the gasket!

In addition, the mounting holes were ever-so-slightly too close to allow all four screws to engage simultaneously, so it required a little reaming.

This is an older kit, from the time I first became aware of them about a year-and-a-half ago, so maybe this has been corrected. I am putting this cylinder aside until I can have it decked.

They have a larger squish but smaller combustion chamber. I would put it on your compression will be fine. Unless you are interested in a performance build. if that is the case I would be more concerned about cutting the divider out of the transfers than decreasing squish clearance.

 

[RIDE-RED 350r]

I just mounted a Hiway closed port 55 and the squish is .0054 inches! without the gasket!

In addition, the mounting holes were ever-so-slightly too close to allow all four screws to engage simultaneously, so it required a little reaming.

This is an older kit, from the time I first became aware of them about a year-and-a-half ago, so maybe this has been corrected. I am putting this cylinder aside until I can have it decked.

Yours isn't the first AM cylinder that has been reported to have a copious amount of squish clearance. Seems to be the norm for those

 

[RIDE-RED 350r]

They have a larger squish but smaller combustion chamber. I would put it on your compression will be fine. Unless you are interested in a performance build. if that is the case I would be more concerned about cutting the divider out of the transfers than decreasing squish clearance.

Now that's the first I have heard that... Good info.

 

[paragonbuilder]

I would be more concerned about cutting the divider out of the transfers than decreasing squish clearance.

Explain please?
[emoji41]

 

[David Young]

In this picture you can see the divider I am referring to. it does not extend all the way up to the port windows it is just in the middle of the transfer
if it extends the whole length it will offer the benefit of smoothing flow and creating direction. instead the tightest part is in the middle, it is kind of like a venturi but serves no purpose and when it exits the tightspot flow will become lazy and miss directed.

look at what is does on the 365xt vs 372xt.

leave the bridge, cut the divider

 

[paragonbuilder]

In this picture you can see the divider I am referring to. it does not extend all the way up to the port windows it is just in the middle of the transfer
if it extends the whole length it will offer the benefit of smoothing flow and creating direction. instead the tightest part is in the middle, it is kind of like a venturi but serves no purpose and when it exits the tightspot flow will become lazy and miss directed.

look at what is does on the 365xt vs 372xt.

leave the bridge, cut the divider

Is the stock jug like this too David?
I've never opened mine up...

 

[David Young]

first is what a 46mm rancher looks like
next is what a hyway meteor kit looks like
last is what the 45mm closed port jug looks like.

you see how the first two can get by with a solid piston but the oem will depend on flow through or by the piston.

 

[RIDE-RED 350r]

An attempt at quad port running characteristics perhaps?? Or maybe for structural strength of the cylinder casting at the transfer to prevent cracking over time?