New Guy - Just Bought a 038 AV Magnum - Where to Start on Maintenance and Mods?

[bulletpruf]

Fellas -

Grew up in the country and am fairly handy with a chainsaw, but have never had a real pro model (have a Poulan Pro 295, but I don't think that counts). Decided to fix that and bought myself a fairly clean 038 AV Magnum on eBay. I paid top dollar for it - about $360+ shipping) - but I'm ok with overpaying for something that I'll probably never sell.

Anyway, the saw looks fairly clean, said to run great, doesn't look like it's been subjected to serious abuse. Of course, that's no reason to leave well enough alone! Frankly, one of the reasons I wanted an older saw is to have something to tinker with.

So, I've done a bit of research, and here's my basic plan -

Compression check

Leakdown test

Check crank pressure -- how do I do this?

Examine cylinder for aluminum transfer and/or scoring.

Change fuel line.

Change impulse line.

Check intake boot for cracks.

New spark plug - Bosch or NGK? What #'s?

Switch from spur to rim sprocket.

Muffler mod? If this is a Magnum, it should have a 3 port muffler, right? If so, can I pick up some power by modifying it?

Port the head? I've got the necessary tools.

I'll do all the work myself. My other toys include a 68 GTO convertible (owner built 455 and TH400), 66 Fairlane GT convt w/428 and 4 sp, 71 Javelin with 401, 4 sp, 72 Alfa Romeo GTV. Owner built, owner abused.

Thanks!

Scott

 

[cus_deluxe]

Your list looks good. Dont forget to check squish clearance, you may be able to delete the base gasket. Also its pretty easy to play with a slight timing advance to see if that helps. Have fun!

 

[bulletpruf]

Ok, I'll check the squish and see if I can tweak the timing.

Thanks,

Scott

 

[LoveStihlQuality]

For pressure and vacuum test, I use a Mityvac Elite on Amazon. Need to block off exhaust port and intake. And connect to impulse line or a special manfold. Others have all kind of tricks . PM me and I'll describe step by step. Suggest getting it running and tuned stock before you begin any mods. Also can get IPL and service manual from the Beg For Manuals thread. Those guys rock!

Sent from my SM-N900P using Tapatalk

 

[bulletpruf]

I'll check out the Mityvac Elite. Got the IPL and service manual. Sending you a PM.

Thanks!

Scott

 

[rocketnorton]

subbed. had 3 supers. got mag this summer. fav creamsicle. a 044's tryin hard to change that, tho...

 

[bulletpruf]

Yeah, I was searching for an 038 Magnum, but the 044 was a close second.

 

[bulletpruf]

Saw arrived today. Looks to be as advertised. Need to do a compression check, pull muffler to check cylinder, and basic cleanup for now. Pics to follow. Thanks

 

[rocketnorton]

mine is @ 155, w/nice piston & gasket. last super was 150.

 

[bulletpruf]

mine is @ 155, w/nice piston & gasket. last super was 150.

Ok, thanks for the details.

Scott

 

[bulletpruf]

038 Magnum arrived yesterday. Seems to be pretty much as advertised.

Came with a 20" bar, a worn out chain, and a new chain.

 

[bulletpruf]

According to the faded plate, it is indeed an 038 Magnum (should be German made, not Brazil) but I'm assuming anyone could swap that cover. so do I need to pull the cylinder to measure or is there an easier way to tell?



Haven't pulled the muffler yet to check the piston.





Lousy picture, but the NGK plug looks pretty good to me - light to medium brown and dry. However, I'm a 4 stroke guy, so I'm not sure if that's good for a 2 stroke or not.



Compression looks good - right at 158 psi.



And a size comparison with the other new saw on the garage - the 070 that arrived from Germany today.



Anyone see anything interesting, jacked up/needs replaced, etc, in any of the pictures?

Thanks,

Scott

 

[rocketnorton]

measure bore when ya take muff off.

52mm = m
50 = s
48 is first version.

your caps are older, as is knob on a/f cover. i'm curious, too.

 

[bulletpruf]

measure bore when ya take muff off.

Yeah, after I posted that, I figured I could stick the tail of caliper into the bore and get a pretty close measurement.

 

[bulletpruf]

Good news - the piston looks great, at least on the exhaust side. It's also 52 mm, so that checks out as a 72 cc Magnum. Serial number is 118721297 -- any way to figure out what year it is from this? According to the acres site, production started in 1985.

Thanks

Scott

 

[bulletpruf]

Cleaning and disassembling. Top cover is in decent shape, but I need a new 038 Magnum tag; anyone know where I can find OEM or a quality aftermarket replacement?

Picked up a new OEM side cover on eBay. The one on the saw was damaged.

Muffler is in decent shape, but not sure how to modify to improve power a bit. Any tips?

Thanks

Scott

 

[bulletpruf]

Found details on muffler mod and realized that I have a single port muffler when I should have a dual or triple port. Anyone have a good dual or triple port 038 muffler that they want to sell?

Thanks

 

[deadtrees]

I have a 038 MAG that I bought new that was made in Brazil. Be careful when modding the muffler. I got a hole too close to the top and it wanted to melt the top cover plastic. I had to cover that hole.

 

[bulletpruf]

I have a 038 MAG that I bought new that was made in Brazil. Be careful when modding the muffler. I got a hole too close to the top and it wanted to melt the top cover plastic. I had to cover that hole.

Ok, thanks for the heads up.

Scott

 

[Big_6]

Ok, thanks for the heads up.

Scott

Fill that (tack weld,) hole with a sheet metal screw.
I did it that way.