husqvarna 61 strange sound? what should I do with it?

[hi5]

Hello everybody! First time poster here. I am after some advice on a saw I have recently bought. It is an old (1990 I think) grey top husqvarna 61. I am a bit concerned about the noise it is making... What do you guys think? Sounds to me like a bearing inside isn't happy or something... It still makes the same noise when the brake is on...

sound and test cuts

The saw is about 120-130 psi compression. I haven't had the cylinder off yet to check the ring gap.

The piston and ring look to be in very good condition.

The cylinder looks slightly scored, I am not too sure if this is significant, I'll try post photos.

I don't really want to spend much more on it but would be quite keen to try a cheap 272 cylinder/carb etc on it... I don't want to re tap any new holes into the case in case this doesn't work well... I think I will replace the piston ring on the current piston before I try this.

What do you guys think? And the noise?!

 

[hi5]

Here is the piston and ring



And the cylinder



Light scoring? Didn't look too deep... But only about 125psi compression so I am not sure...

Thanks again for anybody who has a look

 

[hi5]

...There is also a very small crack in the cylinder where I suspect it was dropped/tree landed on it (the top cover is also cracked).

 

[82F100SWB]

I wouldn't be overly concerned about the cracked fin. It won't hurt anything.
As for the sound, I suspect that you will find the intake side of the skirt is worn quite a bit, and the piston is rocking in the bore.
You can swap to the 272 top end on that saw without drilling or tapping anything on the case. It should fit under that top cover without issues, and you can swap the throttle shaft from your existing carb to keep the old style idle screw.

 

[ballisticdoughnut]

Needs a piston. Can hear it slap when the saw is running, not a big deal. Seems to run pretty good otherwise.

 

[hi5]

I wouldn't be overly concerned about the cracked fin. It won't hurt anything.
As for the sound, I suspect that you will find the intake side of the skirt is worn quite a bit, and the piston is rocking in the bore.
You can swap to the 272 top end on that saw without drilling or tapping anything on the case. It should fit under that top cover without issues, and you can swap the throttle shaft from your existing carb to keep the old style idle screw.

Thanks for the reply. If the piston is rocking in the bore, will this cause more damage to the piston and/or cylinder? Do you think this could be partly due to a worn piston ring (which is maybe also responsible for low compression)?

I shall first try just changing the piston ring... Then maybe I will try a cheap 272 kit... If it doesn't perform well, or still not sounding great then I think I will consider buying a new 61 piston and possibly cylinder... But I shall cross that bridge when I come to it.

 

[hi5]

Needs a piston. Can hear it slap when the saw is running, not a big deal. Seems to run pretty good otherwise.

Thanks for the reply. Do you know why this might be happening? You think a new piston (and ring) will fix this? Any suggestion on piston? The cheap ones look pretty tempting to me...

 

[hi5]

Ok, I have done a bit of research and realise now that you are both saying the same thing (I think). The piston is slapping the sides of the cylinder (due to it being worn/smaller. I think it is worse when the saw is warm which also checks out. Thanks guys, and I will keep you/the thread updated with progress.

 

[ballisticdoughnut]

Thanks for the reply. Do you know why this might be happening? You think a new piston (and ring) will fix this? Any suggestion on piston? The cheap ones look pretty tempting to me...

A new piston and ring will fix it provided it fits correctly in the cylinder. Factory clearance is between .002 and .0025 thousandths. Your best option for that saw would be a Meteor piston and cylinder kit. That saw is 48mm bore, can go to 50 or 52mm. Again though, tolerance is everything. In my experience the aftermarket top ends aren’t the same as OEM.

 

[singinwoodwackr]

Hello everybody! First time poster here. I am after some advice on a saw I have recently bought. It is an old (1990 I think) grey top husqvarna 61. I am a bit concerned about the noise it is making... What do you guys think? Sounds to me like a bearing inside isn't happy or something... It still makes the same noise when the brake is on...

sound and test cuts

The saw is about 120-130 psi compression. I haven't had the cylinder off yet to check the ring gap.

The piston and ring look to be in very good condition.

The cylinder looks slightly scored, I am not too sure if this is significant, I'll try post photos.

I don't really want to spend much more on it but would be quite keen to try a cheap 272 cylinder/carb etc on it... I don't want to re tap any new holes into the case in case this doesn't work well... I think I will replace the piston ring on the current piston before I try this.

What do you guys think? And the noise?!

That’s really low comp for a 61

 

[Tony Mayhew]

I'm not disagreeing with what these wise old owls are telling you one bit! But just for *****&Giggles try taking a piece of rubber fuel line like a carburated car would use and start the saw and put one end by your ear and the other end down around the clutch! When the bearing in the clutch drum gets dry it can make a hell of a racket! And in my 30+ years of mechanicing on cars I have been very surprised how sounds will travel through metal! The one that comes to mind as being the worst is a Ford moduleler engine! But with the saw its an easy one to eliminate it as the culprit!

 

[trains]

Sounds like piston slap to me, pretty clear on the vid.
Not clutch ring or rattle by my ears.

 

[hi5]

A new piston and ring will fix it provided it fits correctly in the cylinder. Factory clearance is between .002 and .0025 thousandths. Your best option for that saw would be a Meteor piston and cylinder kit. That saw is 48mm bore, can go to 50 or 52mm. Again though, tolerance is everything. In my experience the aftermarket top ends aren’t the same as OEM.

My understanding so far is that I would have to change the carb+intake for the 52 (272 cylinder?) bore size right?

 

[hi5]

That’s really low comp for a 61

Yep, this is a big part of the reason I am asking for advice on what to do with the saw... Right now I am thinking a cheap 52mm 272 top end and see how it runs, I can't imagine it could be much worse than a piston slapping 125psi assembly... Hopefully it sounds better too

 

[HumBurner]

Is the slap the higher pitched rattling sound? Hard for my ears to hear on a video.

 

[hi5]

Is the slap the higher pitched rattling sound? Hard for my ears to hear on a video.

idle sound

should be easier to hear in this video...

 

[NSEric]

My understanding so far is that I would have to change the carb+intake for the 52 (272 cylinder?) bore size right?

Yes and no.
You can bolt the 61's carb and intake onto the 272 cylinder but you need 272 carb bolts, they're 4m and the 61 is 5m bolts.
The 272 has a slightly bigger carb and it will make a little more power/rpm than the carb off the 61, if you dont care about getting every last little bit of power the 61's carb is fine.

I put a cheap amazon 272 kit that comes with a carb and intake on a wore out beat up 61.
The aftermarket intake didnt line up with the port on the cylinder very good and wouldnt seal up and the carb bolts were too long. I ended up using the 61's intake block, home made gaskets with the am 272 carb and shortened the bolts. If you reuse the 61's air filter and holder it fits under the top cover fine. I did a little porting on the cylinder and it's quite strong.

 

[singinwoodwackr]

Yep, this is a big part of the reason I am asking for advice on what to do with the saw... Right now I am thinking a cheap 52mm 272 top end and see how it runs, I can't imagine it could be much worse than a piston slapping 125psi assembly... Hopefully it sounds better too

Don't go the cheap route. Stick with Meteor kits or even Hyway if you can't get OE.

 

[cookies]

With internal parts you get what you pay for. If this is just a toy you plan to repair to run a little or play with then put it away on a shelf or sell once running then use a aftermarket kit like hyway or meteor with meteor being a hair better. If you plan to use that saw for real for another 20-30 years get a oem piston or p/c kit and be done with it.

 

[ballisticdoughnut]

My understanding so far is that I would have to change the carb+intake for the 52 (272 cylinder?) bore size right?

You’ll need the 272 intake block, rubber seal, bolts, and gaskets. The 61 carb (most likely a HS163) will work but it’s on the small side for a 272 top end. HS224 is the carb you want. Same size throttle bore and venturi as the stock 272 carb, and has the proper throttle shaft so you can still make idle speed adjustments without modifying the top cover. Can’t speak on using the 61 intake block, never done it. They look similar to the 268/272 block but they’re not the same.