MODED Poulan Wildthing 2375

[Jeff Lary]

http://www.arboristsite.com/chainsaw/65949.htm

Basically a system to address the fundamental problem with 2-strokes, where a portion of each incoming fuel/air charge gets blown out the exhaust port unburned. Strato fills the transfer runners with filtered air (no fuel) so what gets blown out the exhaust is mostly just air with no fuel.

Thanks I think i get it have a good weekend.

 

[leecopland]

Chromed piston or bore

I'm confused with the chrome aspects of Poulan saws, ie some have chromed pistons and some seem to have chromed cylinders.

Questions
1. I'm guessing that an engine can only have one of these chromed either piston or cylinder.

2. If that is true what would happen if both were chromed?

#. It seems to me that an un-chromed, aluminum or magnesium, cylinder would not last long with a steel ringed piston flying up and down.

Please someone put me out of my misery.

Thanks,

Lee:msp_confused:

 

[Eccentric]

I'm confused with the chrome aspects of Poulan saws, ie some have chromed pistons and some seem to have chromed cylinders.

Questions
1. I'm guessing that an engine can only have one of these chromed either piston or cylinder.

2. If that is true what would happen if both were chromed?

#. It seems to me that an un-chromed, aluminum or magnesium, cylinder would not last long with a steel ringed piston flying up and down.

Please someone put me out of my misery.

Thanks,

Lee:msp_confused:

If both surfaces (bore and piston) were chromed, the chrome plating would gall and peel/fail in short order. I share your thought that having the bore (which has the rings riding up and down on) bare, while having the piston (which is supposed to 'float' on a film of oil) chromed seems backwards and a bad idea. However, at least on these Poulans it seems to work very well. The many thousands of Poulan Micro series, Poulan 3400/3800 saws, Poulan weedeaters and blowers, and WT type saws run and last quite well with this arrangement. The lawnmower engines of the 1970's and 1980's with this setup didn't work as well in my experience.

I prefer chromed bores (or iron/steel liners) in chainsaws, but can't really say much bad about the chromed piston saws. My only real complaint with them is that it's harder to make an accurate assessment of the condition of the cylinder of these engines by peaking through the exhaust port. The chrome on the piston is quite durable, and will look fine and dandy even when the cylinder has been roached. Much easier to see (at a glance) when things are FUBAR with the chromed bore/bare piston engines....

 

[Chris-PA]

See my post above (http://www.arboristsite.com/chainsaw/117370-2.htm#post4172225)

What I didn't say is that what I called the Poulan 2250 family is available both ways - the Poulan Pro versions are chromed bore while the Poulan versions are chromed piston. I believe the chromed piston versions have Nikasil bores, but I'm not sure. I have not found them to be as durable.

 

[Eccentric]

See my post above (http://www.arboristsite.com/chainsaw/117370-2.htm#post4172225)

What I didn't say is that what I called the Poulan 2250 family is available both ways - the Poulan Pro versions are chromed bore while the Poulan versions are chromed piston. I believe the chromed piston versions have Nikasil bores, but I'm not sure. I have not found them to be as durable.

The chromed piston saws do not have Nikasil bores. The bores are bare aluminum with a high silicon content IIRC.

 

[Chris-PA]

The chromed piston saws do not have Nikasil bores. The bores are bare aluminum with a high silicon content IIRC.

Thanks - I wondered about that.

 

[Eccentric]

Thanks - I wondered about that.

I went to a Briggs and Stratton school in the early 1980's. They referred to the bores in their 'lightweight' engines as "high silica content alluminum" and said the hard surface was something like .020" thick IIRC (and beyond that the cylinder was 'soft' aluminum). Funny thing is, Briggs sold oversize pistons for some of these engines. They were only .004" or .005" oversize IIRC. The idea was to open up the bore that small amount using an expanding three stone hone. I only did that once (on an 8HP horizontal shaft Briggs on a rototiller). Wasn't too impressed with the results....

 

[old 040]

I'm going to re-post this here because people invariably confuse the different Poulan models:

<blockquote>This is what I've learned about the older plastic Poulan saws – by older I mean pre-strato engines. There are similar Craftsman versions of many of these (not the Husqvarna), which sometimes have slightly different mix of features.

Poulan Wild Thing

Models include the 1950, 2050, 2055, 2150, 2175, 2375, PP210, PP262 in displacements from 33cc to 42cc. There is no anti-vibe and they can be identified by the primer bulb and the distinctive vertical duct bulge that runs from the top of the recoil cover into the top cover. They're not that light and fairly wide, but not too bad either.

The engine is a basic clamshell type with a slug piston and open single transfers. The connecting rod is a flat cross section (stamped?), but is fairly thick and I've not heard of this being a weakness. Flywheels have deep fins and they appear to move a lot of air.

Some have chain brakes, some don't. Clutches are outboard type with simple spur drive sprockets. All use 3/8 LoPro chain. Most use Walbro WT carbs and foam air filter that works OK if it's oiled. The plastic clutch cover/chain brake tend to warp a bit over time, especially with heat from the clutch area, as they are supported only at the bar studs. Bar studs are toggle head bolts and go though the plastic case (as opposed to being threaded into the plastic like an MS250).

Poulan 2250

Models include the 2250, 2550, 2555, PP220, PP230, PP260, in displacements from 36cc to 42cc. These are the same basic design as the Wild Thing family, but have A/V. The A/V uses a spring-type suspension for isolation, which tends to be rather soft and allows a fair amount of movement, but it is smooth. There are considerable differences in the choke and throttle linkages, on/off switch, the carb, the top cover and the air filter mount. The top cover on these has two internal ridges that help keep the air filter seated, which the Wild Thing ones do not have. The choke is located on a terrible position and is really hard to access with gloves.

Chain brakes were optional. All use 3/8 LoPro chain.

Poulan 2500

Models include the 2500, 2600, 2700, 2750, 2775, 3050, PP255, PP295, PP4620, PP310, PP315, as well as the Jonsered 2036 and 2040. Displacements run from 36cc to 49cc. There is no primer bulb, and the Jonsered versions have a different shaped recoil and top cover just for decoration. The engines in this family are different from those in the Wild Thing family saws. For one, the crank is about 1/2” narrower, and the flywheel has shallower fins, allowing the whole saw to be lighter and much narrower as well. They are about 10lbs.

The connecting rod has an I-beam cross section. They use a chromed bore. The exhaust port shape is very similar to the Wild Thing, but the intake is a bit different. These saws respond very well to opening up the muffler and make a surprising amount of power for their displacement. They use Walbro WT carbs and a flocked air filter.

There is an external handle frame with a spring-type suspension for isolation, which tends to be rather soft.

Some of these are labeled “Turbo” and some are “Super Clean” - the Turbo versions use the small scoop by the flywheel fan to keep debris out of the airbox, while the Super Clean ones just have a pickup in the air stream between the cylinder and the carb. Only the Super Clean type parts are available any more, but they mostly interchange – there are some differences between early and later saws regarding the intake boot and impulse line.

Chain brakes are on most later saws. Most of these use 0.325” chain.

I have found three design weaknesses on these saws. First, the muffler heat shield on earlier Type I saws fatigue fails in the area around the muffler outlet. If you have a chain brake it can melt when the deflector falls off, and heat damage around the muffler is common. Second, the engine mount screws often back out. There is no locking hardware and they sit in a floating shoulder bushing that can spin so it would not work well anyway. Locktite will not work well with the thread type on the original screws. Many saws have been damaged by lost or broken screws. Last, the A/V mounts are easily damaged if the saw gets pinched and a gorilla tries to yank it out.

Husqvarna 36

Models include the 36, 136, 141, 142 in displacements from 36cc to 40cc. These use the same engine family as the Poulan 2500 series, but have a different “saddle” type case that fits over the handle/tank and has rubber A/V mounts. The A/V system allows less movement than the spring types used on the Poulans. The size and weight is about the same as the Poulan 2500 family. The air filter looks similar to the 2500 but is slightly different, and all use the Turbo filter scoop. Some of these are 0.325” and some are 3/8 LoPro chain, and the 142s came with 0.043” Microlite. Clutches, drive sprockets and bars interchange on all these saws.

The 142e saws come with catalyst mufflers that are very restrictive. With a little bit of work the muffler and heat shield can be replaced with the parts from the 141, which really helps power.</blockquote>

hmmm.......sure looks like this thang has AV.....

 

[redunshee]

Your right. The 2375 Wildthing was not a strato saw whereas the 4018 series was.

 

[kwhite87]

I tried one of these out for my first porting try. They are right. That saw cuts twice as fast as before. We will see how long it lasts but its a mean s.o.b

 

[John Walsh]

I just love this site! I'm a hot-rodder from way back. I just picked up 2 Poulans and a hard case for $30 from a gentleman from Facebook Marketplace One saw, a 2375 Wild thing, was complete except the owner tried to replace fuel lines unsuccessfully. The other saw is a damaged (looks like tree felled on it) 4218AVX parts saw, which had great compression but damaged top cover and handle, no bar/chain or sprocket cover. Some interesting things about the Wild Thing are that there was a steel insert in the exhaust port, which I removed. The port looks much larger without it. I also did a mild muffler mod since the saw was disassembled far enough to make it pretty easy. Used a straight blade screwdriver twisted in the two rear outlet ports to enlarge them and drilled out the holes in the internal baffle with a 15/64" drill bit. Unfortunately, it looked like the PO tried to force the larger of the two tank fuel lines in, resulting in some damage to the "donut" molded into the top of the hole. I was able to get the saw running in three pulls and it cuts like a SOB. Much better than my older Wild Thing. I have some questions about this newer Wild Thing and some observations about modding saws, particularly these cheap Poulans.

QUESTIONS: 1) This newer WT has a different carb/filter arrangement than my older WT. The older one had a "Pac man" shaped filter housing with a felt filter. The newer one has a different filter housing (think rectangle with top side shorter than bottom)and a foam filter. In the box of parts given to me, there was no cover over the foam filter like my other WT with the felt filter has. Should there be one? If there should be, does anyone have one to sell to me?
2) The older WT has a working chain brake, but the newer WT has a chain brake handle that isn't connected to anything and doesn't look like it ever was. I took sprocket cover off when I found CB handle wouldn't move. WTF? Can one be added? Parts saw has no sprocket cover or CB handle to pirate.
3) The saw leaked gas out of the larger tank hole when I got it running, so I was going to ask posters if they had a fix in mind (remember, hole was boogered a bit). I was going to use a 2 part epoxy at hole/fuel line, but the next day leakage seems to have stopped or been negligible, which I attribute to fuel line conforming to damage, sealing off the leak. If it had continued leaking, any ideas?

OBSERVATIONS: As a new member,I obviously haven't seen even a good amount of the hot-rodding saws posts, but I haven't run across anyone maximizing the stock carbs. In the old days we would disassemble throttle plate and file a round cross section throttle shaft into an airfoil shaped cross section (with throttle fully open), and remove any protruding threads on the plate screw. If this is on other posts, forgive me my newby status. If anyone wants to do this mod, be careful! The throttle plate is precision ground to only fit one way. Often the hardest part of the mod is getting the plate screw backed out, as some manufacturers stake the end of the screw to keep it in place. When reassembling, use red loctite to keep screw in place. If you ever need to remove it, a soldering iron on the screw will melt the loctite.

 

[Yotaismygame]

What were hot rodders from way back doing to saws?

 

[Huskybill]

Gave my son a new wildthing he ran it, beating the snots out of it for 25 years using left over maxima super m dirtbike gas. It’s still running today.

Any two stroke can be modded. I took a 71 suzuki ts125 piston ported and trimmed 1/8” from the piston skirt. It was beating newer Kawasaki kx80’s in the straights. A kid on a 80 complained to his dad that old bike just beat me. The dad grunted that’s a motorcycle. It’s a antique dual sport. Hearing that makes me wish I ported the cylinder. Having 125 cc is 125 cc no matter how old.

 

[John Walsh]

What were hot rodders from way back doing to saws?

Saws were not even on the radar. My favorite 2-stroke was a 1979 Yamaha RD400F. With expansion chambers and bored carbs, shaved heads, it would regularly spank 750 4-stroke sport bikes of the period

Gave my son a new wildthing he ran it, beating the snots out of it for 25 years using left over maxima super m dirtbike gas. It’s still running today.

Any two stroke can be modded. I took a 71 suzuki ts125 piston ported and trimmed 1/8” from the piston skirt. It was beating newer Kawasaki kx80’s in the straights. A kid on a 80 complained to his dad that old bike just beat me. The dad grunted that’s a motorcycle. It’s a antique dual sport. Hearing that makes me wish I ported the cylinder. Having 125 cc is 125 cc no matter how old.

My used WT was a $50 purchase 20? years ago and just wont quit. Went thru numerous chains and 3 or 4 bars, still keeps my outdoor woodburning furnace fed to this day. Muffler modded the non-runner WT I recently bought and it seems to cut even better than the older WT. Love me some saws!

 

[cedarhollow]

not for nothing but i had a pair of wild things, and i was a pulling pro by the time i got them things started, i gave them away and got into stihl's

 

[John Walsh]

not for nothing but i had a pair of wild things, and i was a pulling pro by the time i got them things started, i gave them away and got into stihl's

not for nothing but i had a pair of wild things, and i was a pulling pro by the time i got them things started, i gave them away and got into stihl's

Primer bulb pushed 3-4x, choke on full, first pull it pops, choke off or half, throttle pushed open with my toe, screaming saw on 2nd, or at most 3rd pull, every time