Husqvarna 51

[crashagn]

Puzzled on this 1 so thought I would post to see of some opinions. 51has been working great all summer untill yesterday. I was bucking up some ash and had about a half a tank of fuel through and saw just puttered out. Humm.. ok, so with the bar still in the cut 1 gentle half pull on the rope it started right back up and 4 cuts later it did the same thing. It was a stop like a kiill switch were it just stops, it was a lose of power and 2-3 seconds it died. Not like starving for fuel. But to rule the fuel out I topped the tank back off and it wont even pop over. On the bench heres ths following I did

old plug has darn good spark. It will ignite fuel out of the jug with plug sitting on top.
it will ignite fuel when dumped into the cylinder
It ignites fuel normaly with plug resting ontop of the jug.
it will not pop over with plug in the jug or with a trickle through the carb or a trickle dumped into the jug with plug put back in.
Ive tried new plug, new fuel filture.
With a dry plug in the jug I can pull on the rope 2-3 times and it will not start and after pulling the plug it will be wet
Compression around 100

I have yet to tear the carb off. I have also dumped the fuel out of the tank and refilled. Fuel is fresh mix and no issues with the 371xp and 137

 

[Chris J.]

...Compression around 100...

Your compression is pretty low. Pull the muffler and check the exhaust side of the piston, and pull the carb and check the fuel side of the piston. Something tells me you're not going to like what you see.

 

[Guido Salvage]

Your compression is pretty low. Pull the muffler and check the exhaust side of the piston, and pull the carb and check the fuel side of the piston. Something tells me you're not going to like what you see.

I agree, sounds like there may be a rebuild in your future.

 

[crashagn]

well low and behold there be scratches and grooves when I pulled the muffler. Pulled the jug and looks like i will be ordering (if I can find em from Baileys) New jug, piston and ring and gaskets. Really not to bad for a 7+ year old saw bought from ebay....

 

[Guido Salvage]

Have you tried to clean up the cylinder with acid? I would try that before investing in a new one.

 

[Kenskip1]

51 Husky

If you are going to get a new cylinder why not get a 55 replacement?Besides a cylinder and gasket you will need a compression release.Put a bit more UMPF in your 51. I believe it is a direct bolt on, Ken

 

[Kenskip1]

Something is puzzling me. Why did this happen now? Old mix?A bad gas line? I would take a look deeper into the fuel system.I suspect an air leak.No need to spend the monies and have this happen again, Ken

 

[PogoInTheWoods]

Have you tried to clean up the cylinder with acid? I would try that before investing in a new one.

Absolutely. But before ya start tearin' it down too far to do that, either do, or have done, a vac/pressure test to check for an air leak as the possible cause of the problem. The intake boots on those saws are notorious for developing air leaks. Ya may need to include one in your order.

I'm doing a 51 for my nephew right now. Cylinder cleaned up real nice with the acid treatment and some patience. Now I need to figure out the difference between an EPA and a non-EPA 51 to order the right piston.

Poge

 

[Roanoker494]

Absolutely. But before ya start tearin' it down too far to do that, either do, or have done, a vac/pressure test to check for an air leak as the possible cause of the problem. The intake boots on those saws are notorious for developing air leaks. Ya may need to include one in your order.

I'm doing a 51 for my nephew right now. Cylinder cleaned up real nice with the acid treatment and some patience. Now I need to figure out the difference between an EPA and a non-EPA 51 to order the right piston.

Poge

Model 51 has 45mm bore
51 EPA has 44mm bore

 

[PogoInTheWoods]

Model 51 has 45mm bore
51 EPA has 44mm bore

My IPL is evidently a pre-EPA version.

503-16-77-01 it is. Thanks, mang!

Poge

 

[Roanoker494]

My IPL is evidently a pre-EPA version.

503-16-77-01 it is. Thanks, mang!

Poge

Here is the IPL I pulled the snapshot from.

 

[crashagn]

If you are going to get a new cylinder why not get a 55 replacement?Besides a cylinder and gasket you will need a compression release.Put a bit more UMPF in your 51. I believe it is a direct bolt on, Ken

There wasnt a compression release on it before and I never had a problem drop startin the saw. My 371xp used to have a compression release but not no more.. Dont have a problem startin that 1 or the Makita concrete saw..

I opened up the muffler about 3 months after I bought it and retuned..Again that was 7+ years ago. The grooves in the jug are perty deep.

PogoInTheWoods - Good idea on the intake boot. Will have to add that to the list.

 

[SawGarage]

OUCH!! :bang:

lean, or LACK of oil.....

check for air leaks...

you SURE the saw was retuned properly after opening up the muffler??

 

[crashagn]

OUCH!! :bang:

lean, or LACK of oil.....

check for air leaks...

you SURE the saw was retuned properly after opening up the muffler??

"3 months after I bought it and retuned..Again that was 7+ years ago". I am guessing it was more of a air leak that caused this.

 

[Kenskip1]

There wasnt a compression release on it before and I never had a problem drop startin the saw. My 371xp used to have a compression release but not no more.. Dont have a problem startin that 1 or the Makita concrete saw..

I think that you missed my point.If you did go to the 55 cylinder it has a port for a compression relief pre drilled.This is what I meant. If you decide to go this route then you WILL need the part mentioned,Ken

 

[Brian VT]

There wasnt a compression release on it before...

I think that you missed my point.If you did go to the 55 cylinder it has a port for a compression relief pre drilled.This is what I meant. If you decide to go this route then you WILL need the part mentioned,Ken

I recently put a 55 p&c on a 51 and I plugged the hole with a head-less Allen bolt from the local hardware store.

 

[MechanicMatt]

Ahh, my 50 looked worse when I got it. A bit of acid lots of wet sanding and a new ring and she lives again. Real little screamer now :hmm3grin2orange:

 

[rms61moparman]

Be sure you check the impulse seal real good.
They are bad about breaking down over time and leaking.
I replace them EVERY time I pull the carb on one.


Mike

 

[SawGarage]

Be sure you check the impulse seal real good.
They are bad about breaking down over time and leaking.
I replace them EVERY time I pull the carb on one.


Mike

Gotta agree with Mike there...

I had a 2050 j-red that wouldn't idle down to save my life! and that is why..

they are about $1...

Jay

 

[ncfarmboy]

Gotta agree with Mike there...

I had a 2050 j-red that wouldn't idle down to save my life! and that is why..

they are about $1...

Jay

Please tell me where you're getting them for a $1.00.
Shep