Restoring a Poulan 3400

[redunshee]

If I hold the flywheel and clutch then push push down on one side, while pulling up on the other, there is some rocking motion. There is a little back and forth play but nothing that I think would be a issue. I will have to wait till I get inside the case before I make a decision on the bearings and thrust washers. I have been told that the type of bearing that the 3400 uses will seem loose when compared to ball bearings, but I have no experience to base that on. I have never personally had to replace the crank bearings in a saw before, though I did buy and part out a Husqvarna 394xp that had bad bearings.

I've simply pulled side to side on one side and then the other. If there is play then I guess I'd replace the bearings seeing as how you are going to split the case anyway. A little in and out play is okay. When I've replaced bearings the first thing I did was to do one and compare the depth to the other side. I simply used the correct size socket and knocked it out. You are going to have to replace the crank seals as the bearings are punched from the outside of the case in. They are reinstalled in the opposite direction i.e. from the inside out.
Bob

 

[Roanoker494]

I've simply pulled side to side on one side and then the other. If there is play then I guess I'd replace the bearings seeing as how you are going to split the case anyway. A little in and out play is okay. When I've replaced bearings the first thing I did was to do one and compare the depth to the other side. I simply used the correct size socket and knocked it out. You are going to have to replace the crank seals as the bearings are punched from the outside of the case in. They are reinstalled in the opposite direction i.e. from the inside out.
Bob

That is about what I am figuring on. If I am going to be right there at the bearings and thrust washers, then why not replace them?

 

[redunshee]

That is about what I am figuring on. If I am going to be right there at the bearings and thrust washers, then why not replace them?

Well, it is unusual for the bearings to be bad. They can be but it isn't the norm. As far as Thrust washers I guess I've never replaced them as the end play has never been too bad. However its your dollar so go do it. By the way I've had good luck by putting a thin coat of a good sealant around the outside edge of the crank seals prior to installing. Also heed ModifiedMark's suggestion about wrapping foil etc. around the step on the clutchside crank end. You don't want to have the rubber gasket on the crank seal flip out on you. I also put a little 2 cycle oil on the crankshaft to ease seating the seals. Set them even or slightly below the case.
Bob

 

[redunshee]

a little press for pushing the wrist pin in & out of the rod on these poulans. the key is the joiner nuts for the 10-24 allthread rod. regular 10-24 nuts stripped out on me. it wouldn't hurt to warm the rod up. they are tight.
drill optional.

Help me by explaining a couple parts. I see you are using a socket to accept the wristpin as its pushed out. Are those two large nuts on the pushing side, joiner nuts? Guess I'm unfamilar with the term.
Thanks

 

[Roanoker494]

Help me by explaining a couple parts. I see you are using a socket to accept the wristpin as its pushed out. Are those two large nuts on the pushing side, joiner nuts? Guess I'm unfamilar with the term.
Thanks

I went to lowes today and picked up everything from the hardware department. The large nut you see is called a coupler nut and I bought one steel spacer to catch the pin one slightly smaller than the wrist to pull/push it into the rod. I have built many of these set-ups before for removing/installing suspension bushings on cars.

 

[Roanoker494]

Well, it is unusual for the bearings to be bad. They can be but it isn't the norm. As far as Thrust washers I guess I've never replaced them as the end play has never been too bad. However its your dollar so go do it. By the way I've had good luck by putting a thin coat of a good sealant around the outside edge of the crank seals prior to installing. Also heed ModifiedMark's suggestion about wrapping foil etc. around the step on the clutchside crank end. You don't want to have the rubber gasket on the crank seal flip out on you. I also put a little 2 cycle oil on the crankshaft to ease seating the seals. Set them even or slightly below the case.
Bob

I have decided not to mess with the bearings and thrust washers. Is it possible to replace the seals without cracking the case? They look to install from the outside. I will make note of the suggestions on installing the seals, seems to be very solid advice to me. Being from a automotive background I am familiar with the concept of installing the seals, much like a valve stem seal on a cylinder head.

 

[rms61moparman]

I have decided not to mess with the bearings and thrust washers. Is it possible to replace the seals without cracking the case? They look to install from the outside. I will make note of the suggestions on installing the seals, seems to be very solid advice to me. Being from a automotive background I am familiar with the concept of installing the seals, much like a valve stem seal on a cylinder head.

Possible?..............Yes!

But I wouldn't attempt it.


You will have to have a long pipe to put down over the ends of the crank to press the seals in.
Keeping that rig "somewhat" perfectly perpendicular to the case bores will be a TRICK!
Of course you already know the result if you get it cocked and drive one in crooked.
It just seems a lot easier to split the cases and install the seals.....at least to me.


Mike

 

[redunshee]

Possible?..............Yes!

But I wouldn't attempt it.


You will have to have a long pipe to put down over the ends of the crank to press the seals in.
Keeping that rig "somewhat" perfectly perpendicular to the case bores will be a TRICK!
Of course you already know the result if you get it cocked and drive one in crooked.
It just seems a lot easier to split the cases and install the seals.....at least to me.


Mike

Good point Mike, though I've had good luck using a socket to press in the seals. A 17 or 18mm deep socket fits nice. I am also extremely careful to drive it in perfectly straight though I'd be lying if I said I didn't need to tap one side down a little more than the other at times. Just check your progress as you go and go s-l-o-w-l-y. If you don't need to split the case it can be done and is probably the more common practice. Getting them out is a little more work with the case unsplit.

 

[sefh3]

I would split the case to install new seals. The 3400 is one of the easist cases to split. If you already have the bearings, I would install them. Why not? It's a piece of mind for me.

 

[Raz900]

A little heat on the rod helps with getting the pin in (or out). I heat it up with a MAPP gas torch. You don't want it glowing red, but even a couple 100 degrees will expand the rod a couple .001" making it easier to get the pin through. From my years in the auto engine shop, we heated auto con rods to about 1000 degrees to get pins in with no press. (maybe more... stubborn Ford 302 rods use to get 2 rounds in the timed oven and turned blue/black/white)

Coat everything with a good assembly lube for that first cold start. With no immediate oil to lube bearings and rings, the assembly lube is vital. I use this stuff from VHT, VHT Engine Assembly Lube Link. Also learned that one at the shop. We used it on all bearings, rockers, springs, pins etc (everything except the cam lifters). The aerosol can makes it easy to get into corners and small places.

 

[Roanoker494]

Coat everything with a good assembly lube for that first cold start. With no immediate oil to lube bearings and rings, the assembly lube is vital. I use this stuff from VHT, VHT Engine Assembly Lube Link. Also learned that one at the shop. We used it on all bearings, rockers, springs, pins etc (everything except the cam lifters). The aerosol can makes it easy to get into corners and small places.

Glad you mentioned something about assembly lube, as to this point it had not even crossed my mind. A trashed P/C would be a pretty site on a freshly rebuilt saw.

 

[Roanoker494]

I would split the case to install new seals. The 3400 is one of the easist cases to split. If you already have the bearings, I would install them. Why not? It's a piece of mind for me.

That was my thoughts on the bearings. If I am going to put all the money into a full restoration then I should do the bearings also. Problem is the bearings are showing as NLA everywhere I have looked, thrust washer are still available at $3 each. You, or anyone on here, happen to know anywhere that might have the bearings?

 

[rms61moparman]

That was my thoughts on the bearings. If I am going to put all the money into a full restoration then I should do the bearings also. Problem is the bearings are showing as NLA everywhere I have looked, thrust washer are still available at $3 each. You, or anyone on here, happen to know anywhere that might have the bearings?

Mark gets them from Motion Industries I think!
If I'm not mistaken, he said they were a pretty standard bearing.
He should be back tonight and will chime in I'm sure!


Mike

 

[turtle561]

i got the bearings and seals at a local bearing house. the bearings are torrington BH108-$6ea,same as came out. seals were maybe $4ea. don't have the invoice.
thrustwashers@ $3.50ea. on ordertree.com/ rings $5 ea. from them too.

 

[Roanoker494]

i got the bearings and seals at a local bearing house. the bearings are torrington BH108-$6ea,same as came out. seals were maybe $4ea. don't have the invoice.
thrustwashers@ $3.50ea. on ordertree.com/ rings $5 ea. from them too.

Thank you very much, part numbers are worth a million words to me.

 

[Roanoker494]

I found the bearings and thrust washers locally and got the lower end rebuilt today, already had the seals here. Just waiting on my carb kit and piston rings to get here so I can finish up the mechanical side of this restoration. My gasket kit did not have a gasket for the crankcase halves so I used the black silicone that Mopar uses to make oil pan gaskets, that ought to hold it. I want to thank everyone for the help they have provided.

 

[Roanoker494]

The 3400 is coming along nicely. SO far I have replaced the crank bearings, seals, piston rings, rebuilt the carb, replaced all the gaskets and installed a like new piston and cylinder. I have all the parts here to finish it up, except for paint. The spray cans I picked up earlier ended up to be no good, they were free anyway. As soon as I get it all together I will get some pictures up.

 

[Modifiedmark]

Pictures? Those will be nice to see.

Mike will probably be along shortly asking for a video! :hmm3grin2orange:

Sounds like its coming along good, easy saws to work on aint they?

 

[Roanoker494]

Pictures? Those will be nice to see.

Mike will probably be along shortly asking for a video! :hmm3grin2orange:

Sounds like its coming along good, easy saws to work on aint they?

I will have to say it is a easy saw to work on, have not had any problems yet. Even remembered to pay attention and I put the piston on the right direction the first time. Parts can be a little more troublesome to find, compared to the Husky 50/51/55 saws I was working with. Those Husky's are like the old Chevy 350 engines, there is a million and a half of them out there.

 

[Roanoker494]

Here is how it sits as of now.

Wish I had taken some pictures of the saw while it was completely apart. This is how it sits as of right now, have not done a compression test yet. It had 120psi to start but has now gotten a tight fitting top end, new rings and I eliminated the stock head gasket. Hoping for better numbers now. Going to end up getting another top cover because of the burn marks on this one. A local shop has a NOS black cover for $10, probably going to go that route. Mine was missing the thumb screw that holds the air cover on, going to have to fashion something up there.