Husqvarna 51 really troubling no start

[pcguy2u]

Had lots of symptoms that seemed to be different from one time to the next. Short story; 90 psi compression, new carb, new magneto coil, new plug, new gas filter/hose, fresh gas/oil and it won't even pop. Before new fuel, sprayed some starting fluid into the carb with the butterfly open and not even the slightest pop.

During testing from one time to the next, sometimes the plug was wet and other times it was dry, as it is now; fuel line shows fuel. No priming bulb on this carb.

Pulled the flywheel to inspect the key and it wasn't really well defined, but it didn't look damaged. Could this be timing?

The original coil produced spark that was more obvious when turning the engine over with a drill. New coil shows better spark at lower RPM.

Any ideas?

TIA, Nick

 

[lone wolf]

Had lots of symptoms that seemed to be different from one time to the next. Short story; 90 psi compression, new carb, new magneto coil, new plug, new gas filter/hose, fresh gas/oil and it won't even pop. Before new fuel, sprayed some starting fluid into the carb with the butterfly open and not even the slightest pop.

During testing from one time to the next, sometimes the plug was wet and other times it was dry, as it is now; fuel line shows fuel. No priming bulb on this carb.

Pulled the flywheel to inspect the key and it wasn't really well defined, but it didn't look damaged. Could this be timing?

The original coil produced spark that was more obvious when turning the engine over with a drill. New coil shows better spark at lower RPM.

Any ideas?

TIA, Nick

Well 90 PSI if accurate is not acceptable. Re test, cross check that gauge on another good saw and make sure you keep pulling the saws over till the gauge stops rising. also pull the muffler and look and see if the piston is scored.
When you put new parts on were they Chinese knock offs or OEM?

 

[grizz55chev]

Well 90 PSI if accurate is not acceptable. Re test, cross check that gauge on another good saw and make sure you keep pulling the saws over till the gauge stops rising. also pull the muffler and look and see if the piston is scored.
When you put new parts on were they Chinese knock offs or OEM?

90 psi is a no go!

 

[pcguy2u]

Bought the carb from eBay from a guy that I had previously purchased the same carb from and that one is still working fine. The fact that it won't pop with starting fluid seems to eliminate the carb.

Pulled the cord until the compression stopped rising.

The piston looked find from the carb side. Will check the exhaust side.

Thx...

 

[ironman_gq]

100psi minimum, absolute minimum and that's well due for a rebuild. A healthy engine should have 140+ if the gauge is accurate.

 

[pcguy2u]

The exhaust side is heavily scored. Looks like this one is dead... Should have checked it sooner.

Thx again, Nick

 

[ammoaddict]

The exhaust side is heavily scored. Looks like this one is dead... Should have checked it sooner.

Thx again, Nick

Pm me if you would like to sell it cheap.

 

[Vintage Engine Repairs]

Your second sentence is all I needed to read. 90 psi won’t run.

Edit: Everyone beat me to it.

 

[lone wolf]

Your second sentence is all I needed to read. 90 psi won’t run.

Edit: Everyone beat me to it.

Thats OK there will be hundreds more.

 

[pcguy2u]

Have pulled on a lot of chainsaws and it feels right; I also believe the compression gauge is accurate... But, it is what it is. The saw belongs to my neighbor; just doing him a favor. He's going to list it on Craigslist. Shipping is a problem with a parts saw...

Thanks again,
Nick

 

[lone wolf]

Have pulled on a lot of chainsaws and it feels right; I also believe the compression gauge is accurate... But, it is what it is. The saw belongs to my neighbor; just doing him a favor. He's going to list it on Craigslist. Shipping is a problem with a parts saw...

Thanks again,
Nick

Shipping prob 12.00 - 15.00 with https://www.pirateship.com/rates

 

[ValleyForge]

I think a stihl sells a fix for that …lol

 

[lone wolf]

I think a stihl sells a fix for that …lol

Oh yeah!

 

[Wood Doctor]

I think a stihl sells a fix for that …lol

As Wolfie said indirectly, for about $200 plus shipping. Stihl's fixes for anything cost an arm and a leg.

 

[a. palmer jr.]

90 psi is a no go!

90 is barely usable if the saw has reed valves, 120 or so is minimum with piston ported engine. There are sometimes exceptions of course.

 

[Bubster]

Have pulled on a lot of chainsaws and it feels right; I also believe the compression gauge is accurate... But, it is what it is. The saw belongs to my neighbor; just doing him a favor. He's going to list it on Craigslist. Shipping is a problem with a parts saw...

Thanks again,
Nick

Scored piston/cylinder can make enough drag to make you thing compression is ok.I have been fooled by a few saws.

 

[pcguy2u]

One other thing on the compression. My 55 Rancher has a compression release which temporarily makes it much less compression. But in contrast to the 90psi being a non starter, it always starts??? Hmmmm...

 

[Duane(Pa)]

You could put a Meteor 55 topend on that in a heartbeat. Fun little project...

 

[a. palmer jr.]

Scored piston/cylinder can make enough drag to make you thing compression is ok.I have been fooled by a few saws.

Fuel and oil down in the crankcase also makes it feel like it has more compression than it really has..

 

[a. palmer jr.]

I have an old Lawn Boy mower that has barely 90 psi compression that has run for several years, but again, it's a reed valve engine. I think the reed valve engines are illegal now for some reason.