Author Topic: Stihl 025 250  (Read 5066 times)

0 Members and 1 Guest are viewing this topic.

Offline Fish

  • Piped Saw
  • *****
  • Posts: 309
  • Karma: 39
Re: Stihl 025
« Reply #80 on: July 12, 2014, 05:02:27 pm »
I believe that there was an older coil and flywheel, but I would bet on the Walbro, they have always made a good carb.
I don't think that I will ever be a big Zama fan....

Offline 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6437
  • Karma: 249
  • For The Love Of Chainsaws
  • Location: NCO
Re: Stihl 025
« Reply #81 on: July 12, 2014, 08:16:20 pm »
There's at least two different coils in these.
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Offline 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6437
  • Karma: 249
  • For The Love Of Chainsaws
  • Location: NCO
Re: Stihl 025
« Reply #82 on: July 21, 2014, 08:38:25 pm »
I've been using this 025 saw. I've been encountering difficulty also.

The ignition was missing and intermittent. You know that the original situation with the saw was that the engine unit was loose and jiggling around in the case. The flywheel was hitting the coil. Also the coil wire wasn't routed correctly and the cooling shields had almost cut the plug wire in two. You could see the bare wire. Up inside the spark plug boot, there was some kind of deterioration or oxidation. It was like full of black powder up in there between the boot and the wire. So I put a new coil and wires in the saw. This wasn't easy to do for I had to take the top cover loose except for the buffer on the front and pry for all I was worth between that plastic shield on the intake side of the engine unit and plastic crankcase to get all the wires through a little channel right above the coil so the wires will be on the operator side of the plastic shield. If you do not do this the air flow shield extension on the starter cover will try to cut the wires in two.

I've had trouble with the pull starter coming apart. Something caught and when I jerked on the cord a second time, I pulled the knot in the cord through the handle. Wasn't too bad for the knot caught on the bushing of the starter cover. I cut the knot off - rethreaded the cord up through the handle and tied a fatter knot in the cord.
A couple times later I went to start the saw, it sounded like a 22 rifle shot and the starter would not grab the flywheel.  I took out the starter and the pawl fell off onto the ground. I found the little spring clip hair pin pulley retainer on the ground also. With these parts off the pulley I observed that the post for the pulley on this early starter housing was only like 12mm in diameter whereas the hole in the newer style pulley was some 16mm. You could wobble the pulley all around. There is a raised area on the pulley that fits around a raised area of the flywheel to shield the pawl mechanism from wood debris. But the shield part was worn off on one side of the starter pulley even though it had been recently replaced. Now remember this is the saw with the engine originally jumping up and down inside it. I re-installed the damaged pawl, stainless washer, and pulley retainer clip and started the saw.

Thinking later and pricing the parts I would need, it was cheaper to get another starter assembly. For there wasn't anything any good about the old starter except the spring. It would work but not reliably. The old 1991 025 now has a MS 250 starter assembly. Nothing left of the original chainsaw except the cylinder, flywheel, and crankshaft?

It sure starts, runs, and cuts good now. It has taken a awful lot of parts to make this saw reliable over time by me and the original owner.

Makes you want to think about staying away from another project saw this old?
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Offline 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6437
  • Karma: 249
  • For The Love Of Chainsaws
  • Location: NCO
Re: Stihl 025
« Reply #83 on: September 11, 2014, 01:33:12 pm »
I decided to take a used MS250 clamshell engine assembly and "freshen" it up to have on hand for I have three of these series of saws.

I bought a complete bare engine from Custom Chainsaw Parts on Ebay for $45. The ad said "Good Condition" and they had a 99.8% feed back.

I was thinking that it likely wasn't perfect but I could put seals in it and use it?

I received the engine and it was "as removed from the chainsaw". (Dirty) It had decent compression. The piston looked perfect and almost new on the exhaust side but I looked down the intake boot and the intake side of the piston was as smooth as a baby's behind and there were no machine marks. The crank bearings were very rough with dried crud. Goes to show one that most ads on Ebay are somewhat embellished and the product is never as good as claimed. The bottom line . . . I had a good cylinder. The price I paid was OK for a good cylinder.

So then I decided to put a Meteor piston and rings in the engine as well as seals. As I removed the pan from the engine it was obvious the bearings were rough and the engine was all dried up and had not been run in years. The PTO bearing fell towards the seal which meant it was loose on the crankshaft. Not a good sign. The crank was not galled. I used a bearing clamp and puller on the flywheel side and removed that bearing. So I tried the flywheel side bearing on the PTO side and it was tight and wouldn't start on. So I was thinking that the bearing was of poor tolerance. The bearings were made in Turkey. One seal was not a Stihl brand but the other one was. But here I was without new bearings. I happened to remember I had a set of Husqvarna 372XP bearings and sure enough they were the same size as the MS250 bearings. The old seals were as hard as Kelsey's nuts. But overall, it appears the engine had been repaired to some extent at one time? It had Dirko on the joint between the cylinder and the pan. Someone had done a nice conservative job of applying it also. The cylinder wall was like glass and perfectly smooth.

I heated the new bearings to 350F in the wife's oven and dropped them in place on the crank. The flywheel seal slid right in place but I had to jockey the clutch side seal over the shoulder. You push the seal against the crankshaft and then push the slack side over the shoulder. Then you push the seal the opposite direction and jockey the other side over the shoulder. The bearings fit tight against the counter weights but the seals stand away from the bearings a couple mm. The seals fit in a lipped pocket in the crankcase.

The wrist pin clips were a PITA to get into place with my numb fingers but I got the job done without loosing one. I rolled the rings on the piston. You cannot use a ring compressor to install the piston for the cylinder wall is recessed up in the cylinder. But there are guide ramps for the rings. Get the rings aligned with the locating pins on the piston and everything square and ease the assembly into place.

I had previously used 320 grit wet or dry paper on a pane of glass to level off the pan cap and the bottom of the cylinder. The pan cap was more warped than the cylinder but not off very much. So I applied a very thin coat of Dirko, let dry for a few minutes, and put the pan on. I had a extra set of bolts and the metal bushings from a old case assembly to hold the cap in place until I get ready to use the engine.

That's it - ready to go.
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Online 3000 FPS

  • Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 4459
  • Karma: 273
  • Location: Carpenter, Wyoming
Re: Stihl 025
« Reply #84 on: September 11, 2014, 09:44:45 pm »
Well it sounds like all turned out well.  Great job and how did like the meteor piston.
Are you sure those Husky bearing are going to like being in a Stihl crankcase.
PP 505, 475, 445.

Offline 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6437
  • Karma: 249
  • For The Love Of Chainsaws
  • Location: NCO
Re: Stihl 025
« Reply #85 on: September 11, 2014, 10:30:24 pm »
So far I've only bought Meteor pistons for my chainsaw escapades. They have all had the non-eared wrist pin retaining rings.

This Meteor piston was bought from HLS and the USPS tried its best to ruin the piston Plus USPS took the piston on a national excursion to Minot North Dakota from Miami and then to Cleveland and eventually here. The box was rolled into a ball. The wrist pin bearing was squashed flat with the needles all loose out of the cage. HLS sent me a new bearing and it came directly here no problem. I measured the piston every way and could not see anything wrong with it despite the shipping box damage.
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Online 3000 FPS

  • Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 4459
  • Karma: 273
  • Location: Carpenter, Wyoming
Re: Stihl 025
« Reply #86 on: September 11, 2014, 10:41:36 pm »
When you run it let me know what you think.
PP 505, 475, 445.

Offline 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6437
  • Karma: 249
  • For The Love Of Chainsaws
  • Location: NCO
Re: Stihl 025
« Reply #87 on: September 11, 2014, 11:33:04 pm »
Last year, in the early spring, I used a Meteor in a Dolmar 115i and another Meteor in a Dolmar 6800i. Both have run perfect. I bought the pistons from the Israeli.

With the 115i, it free ported about .010" but the saw ran fine.

I bought a couple single ring Meteor pistons for Husqvarna 372's last summer, also from Israel, but have not used them yet. I did fit them in the cylinders and everything seemed OK.
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Offline 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6437
  • Karma: 249
  • For The Love Of Chainsaws
  • Location: NCO
Re: Stihl 025
« Reply #88 on: September 17, 2014, 03:13:13 pm »
1991 Stihl 025

This is the saw from previous posts. Hardly anything is 1991 about it anymore except the cylinder and crankshaft. The engine was rebuilt at sometime in the past. Most everything else except the top cover and filter cover is MS250. To see it setting on the tailgate of the truck, it is a 025 with a MS 250 tank and starter assembly. Most everything else is not 1991 era including the 025 top and filter covers or the air filter. The carburetor is also a Walbro WT-215 which is larger than the original Zama.

I used it some today. I used my MS 250 Monday.

This older 025 certainly holds its own with the MS 250 in spite of the smaller bore. It is a very healthy running 44cc chainsaw. A real joy to use. As to which of the three saws I have, to use one, it would depend more on how sharp the chain was and how much gas and oil was in which chainsaw.

If you've used some of the Chinese produced home owner saws in Homelite, McCulloch, and Poulan style brands, The Stihl 025/MS250 series of saws really shine if they are tuned up correctly in spite of them being a plastic body, clamshell style, home owner class chainsaw.

The fact that little of the original chainsaw remains, goes to show how a long term use firewood chainsaw can be kept up as long as reasonable care and parts are available. The Stihl 025 came out in 1991 and its updated brethren, the MS250 was last made early this year. So the saga went on for 23 years.

I have several older Stihls most of which are 2000 or newer. In rebuilding some of them, it is no more expensive than rebuilding a box store Chinese made yard device.
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Offline Cut4fun .

  • Administrator
  • Nitro Hotsaw
  • *******
  • Posts: 21876
  • Karma: 522
  • OHIO REDNECK Saw Repair Getter Done
    • Redneck Chainsaw Repair
Stihl 025
« Reply #89 on: March 29, 2015, 01:59:22 pm »
Had a stihl 025 dropped off.

Complaint is. Once it is hot from cutting and he refuels. Wont start or very hard to start, almost like flooded he thinks.

Whatcha think?  Going to see if I can get it to do it before I start. I was thinking the tank vent but who knows right now. Tank vent wouldnt make act flooded I wouldnt think. Plus he never pulled plug to confirm anything like wet plug.
REDNECK Saw Repair Getter Done

 

Related Topics

  Subject / Started by Replies Last post
Stihl 026 260

Started by Cut4fun « 1 2 ... 9 10 » Stihl

98 Replies
6132 Views
Last post May 13, 2019, 03:00:53 pm
by Cut4fun .
2 Replies
1299 Views
Last post March 21, 2011, 08:19:57 pm
by Cut4fun
Stihl 038

Started by Cut4fun Stihl

9 Replies
1768 Views
Last post September 30, 2019, 10:00:23 am
by Al Smith
Stihl 070 090

Started by Roanoker494 « 1 2 » Stihl

15 Replies
1431 Views
Last post December 14, 2013, 03:02:01 pm
by Cut4fun .
Stihl 024

Started by Cut4fun Stihl

5 Replies
4148 Views
Last post July 13, 2018, 06:14:59 am
by Al Smith
Stihl 034

Started by Cut4fun « 1 2 » Stihl

10 Replies
706 Views
Last post July 07, 2012, 04:41:10 am
by brokenbudget
0 Replies
262 Views
Last post December 26, 2013, 09:50:16 am
by Cut4fun .
10 Replies
566 Views
Last post September 28, 2017, 09:10:54 pm
by Cut4fun .
0 Replies
321 Views
Last post June 21, 2016, 04:24:11 pm
by Cut4fun .
0 Replies
95 Views
Last post May 29, 2019, 11:11:14 am
by Cut4fun .