What do I do with it now....(First Project Craftsman 3.7)

[Magic_Man]

So I've been a long time lurker here but only recently joined. Hanging out with you guys has given me a bad case of CAD. I was looking for a first project saw when low and behold I tripped over this thing at my father in laws old garage. His garage has been closed for 10 plus years and who knows how long the saw sat there before then. It's crusty and covered in grease as you would expect for sitting in the corner of a full service auto garage for all those years.




So the first thing I did was tear it down and give it a once over. Gas was gummed up,but it had fire and a fresh plug. Piston shows some wear and a few marks, but I've seen worse. It is wearing a practically new Oregon 18" bar with a Stihl chisel chain. My research shows that this is a Poulan 3800 if I am correct.





After tearing it down I decided to try to bring it back to life. Went to the local saw shop and picked up a carb kit, fuel line, and filter. Carb cleanup and fuel line was quick and easy. I flushed the tank several times with mix gas until it was clean. I can see why this hobby is so addicting. Back together and time for a test fire, let's see if it still has any life left in it.



I set my carb screws to 1 1/2 turns out and started yanking. It took a while but eventually I got a pop, then a half choke fire. Took a few minutes to warm it up and adjust the carb in, saw seems to run ok but still starts hard even warm.

Decided to go to town and buy a tool I didn't have yet, a compression tester. Came home and that's when I found this.


It's best test was this one at a hair over 115psi and took lots of pulling to get it,the two tests before this landed at 105 and 110psi. Is this normal for these saws or am I beating a dead horse ? If it's a dead horse what else can be done ? Seems Poulan 3800 top ends aren't laying around everywhere and certainly aren't cheap like the orange colored saws. I certainly can't hurt it, and only have about $15 worth of parts in it at this time. I do recall finding a post long ago about a Poulan/Stihl hybrid of sorts.......

 

[joe25DA]

115psi isn't great. Might be runnable, the 3400/3800 saws typically run well around 125psi and 140psi would be high. The 3700/4000 saws usually pump better numbers 150psi to 160 both mine are in there.
How's is the piston, in your picture we only see a bit of the crown. Let's see that then if it's ok pull the jug remove the base gasket Moto seal it and a new set of rings, you did the carb and fuel lines already. Real easy saw to wrench on

 

[67L36Driver]

Top end is shot. You might get by with just piston & rings or just rings.
110 won't cut wood.

 

[blk05crew]

115psi isn't great. Might be runnable, the 3400/3800 saws typically run well around 125psi and 140psi would be high. The 3700/4000 saws usually pump better numbers 150psi to 160 both mine are in there.
How's is the piston, in your picture we only see a bit of the crown. Let's see that then if it's ok pull the jug remove the base gasket Moto seal it and a new set of rings, you did the carb and fuel lines already. Real easy saw to wrench on

Well said Joe, I'd resurrect it for sure.

 

[Wood Doctor]

I must admit that I worked on one of these saws three years ago at a friend's request. It runs perfectly today.

2.54 x 2.54 x 2.54 x 3.7 = 60.63 cc

Because 3.7 cu. in. may be just an approximation, the actual cc displacement could be larger than this. Figure about 61 cc.

 

[Magic_Man]

115psi isn't great. Might be runnable, the 3400/3800 saws typically run well around 125psi and 140psi would be high. The 3700/4000 saws usually pump better numbers 150psi to 160 both mine are in there.
How's is the piston, in your picture we only see a bit of the crown. Let's see that then if it's ok pull the jug remove the base gasket Moto seal it and a new set of rings, you did the carb and fuel lines already. Real easy saw to wrench on

I will pull the muffler back off and get a better picture of the piston or I may just go ahead and clean it up well enough to pull the jug and take some pictures that way.

 

[rustycj82]

Like you I am a new member too. The saw my not be worth much fixed up but the way I look at it if the price for parts aren't bad it's worth the adventure. I've fixed several lost causes in my day and have sunk too much money but i gained a lot of knowledge. I say go for it and take pics.

 

[Magic_Man]

Like you I am a new member too. The saw my not be worth much fixed up but the way I look at it if the price for parts aren't bad it's worth the adventure. I've fixed several lost causes in my day and have sunk too much money but i gained a lot of knowledge. I say go for it and take pics.

That's where I am with it too, I don't mind spending a few bucks on parts to earn some education and confidence. I would rather screw up something on this saw than screw up a valuable saw.

 

[Justsaws]

You need to look at the intake side of the piston. If the saw has seen a good bit of work the intake side could be well worn and many times that also renders the cylinder unusable. Lots of those saws were run with air filters that were decorative, passing the fines into the cylinder and ruining the intake side.

Good runners when they are in good shape. Track down a new air filter before spending money on a piston and or cylinder. Used to be after market air filters commonly availible, do not know anymore.

 

[Magic_Man]

You need to look at the intake side of the piston. If the saw has seen a good bit of work the intake side could be well worn and many times that also renders the cylinder unusable. Lots of those saws were run with air filters that were decorative, passing the fines into the cylinder and ruining the intake side.

Good runners when they are in good shape. Track down a new air filter before spending money on a piston and or cylinder. Used to be after market air filters commonly availible, do not know anymore.

I'm going to clean it up and pull the jug tonight. I will post pictures of what I find for everyone to see.

I picked up a new air filter when I was at the saw shop, they had a few on hand. Really the old filter was in pretty good shape but was rotting away from age. I do need to address the gasket the filter sits on, it's not in the greatest of shape.

 

[JonCraig]

I second those that say to fix it. I had a 3400 that REALLY surprised me. Was easy to work on, and VERY strong runner. From back in Poulan's golden days...

 

[Chris J.]

That saw is definitely worth getting going. The 3400 and 3700 were big sellers for Poulan, even more so if you take into account the ones sold re-badged for Craftsman, and other companies.

I'm thinking a runner might set you back about $80.00 (maybe more, maybe less, a lot depends on where you live, and plain old luck). Since you got it free, and have spent about $15.00 so far, you could spend another $65.00 before you go into the "red."

I have two Craftsman (Poulan) 3.7s. The runner cost about $60.00. The one that was stored for a couple years (maybe longer, the guy didn't know the last time his deceased uncle ran it) cost $35.00.

 

[Magic_Man]

Tore it down and took some pics last night. Everything looks ok to me, but I am a greenhorn when it comes to chainsaws. So if you guys could give me your opinion on what you see I would be great-full.

Intake Side:


Exhaust Side:


Intake Side:


Exhaust Side :

 

[Chris J.]

I'd lean toward a better piston, VG condition used, or new (if available). The intake side looks pretty rough.

 

[1Alpha1]

Poor chainsaws. Most get used, abused, run hard, and then put away wet.

Where's the love?

 

[joe25DA]

I'd clean up the piston a bit, ring it and Moto seal the jug. Not bad at alk

 

[Wood Doctor]

Poor chainsaws. Most get used, abused, run hard, and then put away wet. Where's the love?

True, true. The only reason the one I worked on was still running is that I think it's been used about five times in 20 years. However, for owners who only use them occasionally, they seem to perform OK.

 

[Magic_Man]

I'd clean up the piston a bit, ring it and Moto seal the jug. Not bad at alk

Pardon my lack of knowledge, what do you mean by " clean up the piston" ?

 

[joe25DA]

Pardon my lack of knowledge, what do you mean by " clean up the piston" ?

Polish it up with some Emory cloth or 600 grit. That piston is chromed, not that it matters cause I've done it to bare Pistons too.

 

[Magic_Man]

Polish it up with some Emory cloth or 600 grit. That piston is chromed, not that it matters cause I've done it to bare Pistons too.

Thanks, I found a ring set on eBay for $17.99 shipped.
Do I need to do any prep to the cylinder before I put it all back together ?