Partner P100 Super surging

[dave86]

Hi all.  I just picked up a nice Partner P100 Super.  It seems to be in good mechanical shape, it starts with two pulls.  The problem is that it surges when running.  Any ideas on the likely problem and required fix?  Thanks.

[Guydreads]

Hmmm, sounds like crank seals very possibly. Could be a tuning issue, or the saw being quite lean. I don't know, I would have a better idea if you described "surging" a bit more.

[sablatnic]

Mine surged badly till I found the correct air filter for it. 
The normal rectangular Partner filter, but with a spacer insert in it. Surged without the spacer.

[Al_Smith]

"correct filter "  not that easy to find .It was just blind luck that I found four for $20 on flea bay .
Now a stab in the dark about the surging and it's only a wild guess .The ignitions on these things are of two types .The "ignitron " early type is nearly impossible to find .If so  they are very costly .I had one cut out ,intermittent failure .I replaced it with an after market coil for a 272 Husqvarna and that cured it .
Now another thought if that coil had been replaced with a coil from a concrete saw .I think like 1250 or whatever those are rev limited coils and will appear to cut out at higher RPM's .

[motzingg]

Not knowing anything about this particular saw... Any saw that's been sitting for awhile I always start with the metering diaphragm in the carb.  9/10 times that's the issue.  

[Al_Smith]

That too .It's a simple very popular and dependable carb, Tillotson model HS .Rebuild kits are inexpensive .

[sablatnic]

It might have a rev limiter in the carburetor, a brass cheese headed screw in the left side of the carburetor.
To show what it looks like, the rev limiter is the brass screw on the right side of this carburator:  https://www.hlsproparts.com/v/vspfiles/photos/HS-175D-2.jpg

[Al_Smith]

Not that I'm aware of it .That's a Husqvarna 2100 I think .

[Real1shepherd]

No, a Partner P100 was NOT a Husky 2100 in another color.

The PM1000, the Partner P100 and the Jonsered 1020 were all the same saw. Maybe you were talking about the carb pic, who knows......

Kevin

[sablatnic]

A few photos. I don't know, if it was used on the HQ 2100, but it was used on many Partners and Jonsereds.
If it is bothering you, you can block it from working by inserting an "office tablet" in the hole before inserting the limiter.
This isn't from a P100 but from  an S55 type saw, but same limiter.


 

 

 

[Al_Smith]

Unless you know the history of the saw you wouldn't know if the ignition is limited coil or not except if it's two piece "ignitron " unit which is unlimited .It could have been changed to a limited coil because those are easy to find .
Just a guess once again but I would think if it "surges " on a dead stick ,not under load but hits it a lick every time in the cut it's likely it's a  limited coil .Another guess if it's limited it should run about 8,000 .Which on a concrete saw would be about 5,000 RPM on the wheel speed .I've tossed chains but I'd never want wheel come apart .Scares me and I'm fearless.  

[Al_Smith]

I like this model of saw plus as a rule all Partners .What I don't like is how they present the IPL's .No description ,just numbers .As luck would have it in addition to the Partner P-100  I also have the McCulloch PM 1000 that has the descriptors .It BTW shows a one piece ignition coil rather than a separate trigger unit . 

[Real1shepherd]

A few photos. I don't know, if it was used on the HQ 2100, but it was used on many Partners and Jonsereds.
If it is bothering you, you can block it from working by inserting an "office tablet" in the hole before inserting the limiter.
This isn't from a P100 but from  an S55 type saw, but same limiter.


 

 

 

That governor was very common on big Tilly carbs.....all the 2100's had it. We plugged it with metal.

Other loggers bragged about using beer can aluminum, I used brass shim stock. It's a nominal punch size.....can't remember it offhand.

Kevin

[Al_Smith]

Regarding the Husky 2100 mine came from some island  off the state of Washington with a bad ignition .Which of course I replaced .What had been done to it I have no idea but assume the gov has been defeated because it will wind right up .It's got a K and N air filter and a V stack so I might assume it's been worked over some what .I've never had it apart and don't remember if I've ever fooled with the carb .That said it's a very powerful old saw and certainly is not slow .Commenting between the two ,Husky and Partner they all run 8 tooth 3/8" rims and will handle a 32" bar like childs play .Once again this is Ohio and seldom does one need this large of a saw and thus they spend most of the time resting on the shelf .Kind of hard to wear them out that being the case . 

[sablatnic]

It BTW shows a one piece ignition coil rather than a separate trigger unit .

Agree on the IPL.

I've seen them with 'mono block' ignition, with two blocks on the cylinder, and with a block in the console for the rear handle.
One of them need earth through the ignition switch to work, so has a normally closed switch opposed the normally open switch,  cannot remember which, but it has caused problems when changing from one type coil to another.

[Al_Smith]

It was a learning curve for me because I'd never worked on a Partner before .The P-100 in my opinion was the most thought of design of any brand I'd ever worked on .The oiling system being internally driven is just about flawless with provisions to oil the clutch bearing through a tiny weep hole in the crankshaft plus it has a thumb oiler .
My only complaint is the use of hex head ,flanged bolts to hold things together and almost impossible to remove on some of the case bolts. It had one torx head screw in the entire assembly which held the retainer for the flywheel side bearing .Little tiny thing 4MM ,I almost missed it .
Partner was very popular for concrete saws in this area back in the day .However this is not high impact high production logging  in this area being usually just selective hard wood cutting .These saws were not inexpensive although well made .
As it worked out from another web forum I was offered a complete dealers book on Partner which helped a lot especially with my lack of knowledge on these things .A little bit of knowledge goes a long way .
It was two saws and three crankcases and two years finding all the parts .Then about 4-5 days I had them both running during the worst  of the lock down .I've got a few dead and down trees large enough for saws of this size I need to cut up this summer so they will be tested eventually .Right now both have 24" bars  but I do have several 32" I could use .I might mention neither the P-100 Super or the McCulloch PM 1000 have governed  carbs because they will wind up .

[Al_Smith]

I might further mention these things have massively strong crankshaft bearings .I don't see how you could ever wear them out unless you get stingy with the mix oil ratio . Had it not for the fact I had the McCulloch IPL I never would have found the cross reference for the crankshaft seals ,the Partner list was just numbers I couldn't cross to anything .However the original seals were marked for size which you don't find on most seals .I saved them for future reference .

[Al_Smith]

Here ya go the only thing I've found different is the side brace on the P-100 Super .I think the reason behind it was to correct for a design flaw of using the back of the crankcase as a pivot point for the anti vib system  .If dropped it will break the tabs off like a match stick .I might add the D-handles are because these things are high compression with no decomp .I'm not some tough Paul Bunyan type west coast feller with blacksmith hands and gorilla muscles .That's been gone long time for me .

 

[dave86]

Hmmm, sounds like crank seals very possibly. Could be a tuning issue, or the saw being quite lean. I don't know, I would have a better idea if you described "surging" a bit more.

At full throttle, while cutting, the speed is not constant.  The engine revs up and down. Tuning it richer did not help.

[dave86]

A few photos. I don't know, if it was used on the HQ 2100, but it was used on many Partners and Jonsereds.
If it is bothering you, you can block it from working by inserting an "office tablet" in the hole before inserting the limiter.
This isn't from a P100 but from  an S55 type saw, but same limiter.


 

 

 

Thanks.  I made a limiter with a disk of gasket material.  Problem solved.

[sablatnic]

Don't let it rev too high, I've seen a couple of broken crankshafts in the past.

[Al_Smith]

No worries here because I've got them all tuned for power 4 cycling out of the cut .

[dave86]

No worries here because I've got them all tuned for power 4 cycling out of the cut .

Sounds like a good idea.  I will fatten it up.

[Al_Smith]

It's just something you learn after a while .One is it takes fuel to make power .Two is a slightly richer air and fuel ratio burns slower so it doesn't cook the piston .Three extremely lean mixtures might make a lot of noise but they almost die on the vine getting down and  dirty under load .Some people take a long time to let that sink in .

[sablatnic]

I prefer to let the limiter stay, doing its job, and then tune the saw in the cut, but du as you want, just remember that no parts are to be had.