Qty of 4 Poulan PP4218's - Cannot get carbs tuned.

[Fordiesel69]

How likely are these to have crankcase air leaks? I cannot get the carbs to adjust, and when they warm up they run lean, when cold they run to rich. I tried an aftermarket carb and they do the same.

And what is really funny is the 3618 has a factory 42cc engine in it. Not sure if this is on purpose or if someone was into it.

 

[jeepman3071]

That's odd about the 42cc engine, never seen that. As far as air leaks, with the saw running you can spray a bit of carb cleaner behind the clutch near the seal, and same on the flywheel side with the top cover off. If it dies you have a crank seal air leak.

 

[Slick3914]

J.U.N.K.

 

[jhs914]

J.U.N.K.

I owned a Poulan years ago. Junked it and bought a Husqvarna that has been bullet proof. Unfortunately I've heard that the lower priced Husqvarna's are now just rebranded Poulan's.

 

[97K15004WD]

Vacuum leaks can cause that for sure. Crankcase, carb, impulse lines, etc.

If it won't adjust out, and you have the OEM carbs, then you most likely have a leak.

Do you have a vacuum tester?

 

[wag123]

Vacuum leaks can cause that for sure. Crankcase, carb, impulse lines, etc.

If it won't adjust out, and you have the OEM carbs, then you most likely have a leak.

Do you have a vacuum tester?

A crankcase leak on a 2-cycle is not the same as a vacuum leak. It can't be tested with a vacuum gauge.
This POS chainsaw is known to have problems with the crankshaft seals/bearings, leaks are very common around the outsides of these seals. First make sure that the cylinder isn't scored, another common problem on this model. The only thing that you can do is take it apart and reseal it (and hope it works). You might try using anaerobic sealant (Loctite 515) around the outsides of the seals (in addition to the lower crankcase itself).

 

[Fordiesel69]

Yep, cylinders look good, I pricked the rings and although the pistons are varnished a little, the ring is completely free in the groove. I have access to a vacuum tester but I do not have a way to block off the intake side of the cylinders. I have blanking plates for the exhaust side.

I am never going to say these are decent saws. I got them in a whole truck load of 2 stroke stuff, and just need to get them running acceptable to be able to unload them cheap.

 

[Cujet]

I'd suggest that you could unload them for a few $ each, as-is and come out ahead financially, with far lower time invested. They don't run well because they are made poorly.

 

[97K15004WD]

I have rebuilt many chainsaws over the years. You vacuum test and pressure test them to find leaks.

On my Sthil MS880, there was a small leak in the case seal. Found with a pressure test.

The saw had previously passed the vacuum test. That's why you do both.

However, if the OP has a vacuum tester, that's one step towards solving the problem. It should hold pressure or vacuum for several minutes with no loss.


8.3 Leakage Test
Defective oil seals and gaskets or
cracks in castings are the usual
causes of leaks. Such faults allow
supplementary air to enter the
engine and upset the fuel-air
mixture.
This makes adjustment of the
prescribed idle speed difficult, if not
impossible.
Moreover, the transition from idle
speed to part or full throttle is not
smooth.
Always perform the vacuum test
first and then the pressure test.
The engine can be checked
thoroughly for leaks with the pump
0000 850 1300.
8.3.1 Preparations
Models with muffler secured with
spring clamp
– Remove the muffler, b 8.1
– Pull off the boot and unscrew the
spark plug.
– Set the piston to top dead center.
This can be checked through the
spark plug hole.

 

[2strokeNorthstar]

A crankcase leak on a 2-cycle is not the same as a vacuum leak. It can't be tested with a vacuum gauge.
This POS chainsaw is known to have problems with the crankshaft seals/bearings, leaks are very common around the outsides of these seals. First make sure that the cylinder isn't scored, another common problem on this model. The only thing that you can do is take it apart and reseal it (and hope it works). You might try using anaerobic sealant (Loctite 515) around the outsides of the seals (in addition to the lower crankcase itself).

You can also use 3 bond 1311, Yamabond,Hondabond. Whatever is easy to get. To test for leaks you need to seal intake and exhaust ports and pressurize the bottom end. Usually if you suspect a leak, it's true. Especially on small cheap motors.

 

[Fordiesel69]

Would motoseal at orieleys work ok for this?

 

[97K15004WD]

Would motoseal at orieleys work ok for this?

Tinman says yes

 

[97K15004WD]

Go to 9:58 and see what he uses:

 

[jeepman3071]

Love Tinman's Saws. Great guy with lots of info.

 

[Fordiesel69]

His videos are what got me off my a$$ to get my cs-670 up and running....

I just cannot get motivated in working on these cheapies. I think it is evil theybwould make the clamshell crankcase so shoddy that they cannot even wear out their first bar and chain b4 it starts to have an air leak.....

 

[jeepman3071]

His videos are what got me off my a$$ to get my cs-670 up and running....

I just cannot get motivated in working on these cheapies. I think it is evil theybwould make the clamshell crankcase so shoddy that they cannot even wear out their first bar and chain b4 it starts to have an air leak.....

I hear ya, I tend to gravitate toward the older better built saws over cheapies. Working on a Jonsered CS2240 currently that I picked up cheap for a friend. He had a little battery saw that wasn't cutting it, and was ready to buy a walmart cheapo chainsaw since it was all he could really afford. This saw should serve him much better.

 

[Fordiesel69]

I never followed thru with an update. All the poulan saws that were PP4218's and the 3618 I just unloaded them cheap. None would run good and I was not able to determine if there was an air leak. Had zero interest. There were other saws in the truck load more worth my time like a Husky 55, 350, 450, T435, and then some older non strato port poulan (the bright green ones) that were able to be restored.

Once I ready how bad the crankshafts are (that snap off) I decided to not spend once more second diagnosing. Why the crankshafts are so small for where the clutch rides is totally beyond me.

 

[nbpt100]

I never followed thru with an update. All the poulan saws that were PP4218's and the 3618 I just unloaded them cheap. None would run good and I was not able to determine if there was an air leak. Had zero interest. There were other saws in the truck load more worth my time like a Husky 55, 350, 450, T435, and then some older non strato port poulan (the bright green ones) that were able to be restored.

Once I ready how bad the crankshafts are (that snap off) I decided to not spend once more second diagnosing. Why the crankshafts are so small for where the clutch rides is totally beyond me.

It is good to know when to take a pass and move on. If you are fixing something to learn, that is one thing, but if your goal it to make a business from it then 2 cycle hand held products can be a big crap shoot with out all the right tools and knowledge.

 

[jeepman3071]

It is good to know when to take a pass and move on. If you are fixing something to learn, that is one thing, but if your goal it to make a business from it then 2 cycle hand held products can be a big crap shoot with out all the right tools and knowledge.

+1

I rarely work on cheap 2-stroke equipment these days, since the customers usually don't want to pay to fix it, and they usually need EVERYTHING in order to run again. Carb kit, fuel lines, filters, etc. Commercial grade saws or even the decent "pro-sumer" saws are worth it.

 

[IndyIan]

I have a husky 141(similar if not the same) and it wouldn't run right either after hundred hours. Neighbor messes with these and just drilled a 1/4-3/8" hole through the muffler, and now runs great again!
It is light plastic junk, but it is light, and narrow, and happily eats anything under 8" hardwood, and its a good saw for clearing branches off conifer trees for trails, and I did a ~100 cedar posts with it.