038 super top end rebuild

[KarlD]

Mine has a bing 48 on it. I’ve just bought a bing 48a rebuild kit...hope it’s going to fit.

I’m rebuilding this saw for kicks, I think I’ll put an 18” bar on and enjoy the grunt

 

[KarlD]

no port in back half?

No, nothing other than the Louvre...and it gets worse

 

[Mad Professor]

You want to get a muffler case with two outlets, or ad an outlet. They made a triple port muffler, but I've never seen one.

IMHO 038S Tilliston and 038M Bings run the same in my 038M conversions. The early 038 Tilly had a smaller bore. Bing part$ are expen$ive

 

[rocketnorton]

i dont have a pic handy, but ya need rear port & opened some, as mentioned.
maybe he has one.
i, too, have not seen the 3p.

 

[KarlD]

My plan, which might be retarded, is to remove both baffles and drill an appropriately sized hole/holes (80% of the size of the cylinder exhaust port?) in the front or side of the muffler. I’m not worried about noise too much or sparks at all (I’m in the wet UK) but just want maximum power. I also don’t really care how it looks. Thanks for the feedback guys

 

[Mad Professor]

Dual port mufflers are common and easy to modify. Even just get the inner case, used

If you want to use yours, do a search: member Lakeside53, stihl 361, muffler mod. Pics are gone but a great thread.

 

[KarlD]

Ok lol I will rethink. I’ll have a look at the thread too. Is this the sort of muffler you’re talking about! Seems expensive!
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/323876423271

 

[Mad Professor]

I've found whole used dead saws for <<less $$$. But that is the better inner casing.

 

[Teemore]

An aftermarket 038 dual port exhaust isn't too expensive - this seller is UK based too: https://www.ebay.co.uk/itm/Exhaust-...103431?hash=item469ae05387:g:qtsAAOSwhFZdSaor

Post-Script- I've had luck with AM 52mm cylinders sold by this UK based Ebayer _ https://www.ebay.co.uk/str/MENDASAW-LIMITED?_trksid=p2047675.l2563

 

[KarlD]

I’ve just ordered that muffler, save compromising the build by modding the old one badly.

I’ve also decided not to mess with the porting until I know a fair bit more...so the saw will be staying in bits until I’ve done some reading.

Reason for this is that minimal reading on here shows me that making a positive impact on performance is not as easy as just widening the exhaust port. When I realised I didn’t know what transfers were or what they did, amongst other things, I decided I should get a book first.

Thanks for the help and advice fellas, I will be busy for a while

 

[KarlD]

An aftermarket 038 dual port exhaust isn't too expensive - this seller is UK based too: https://www.ebay.co.uk/itm/Exhaust-...103431?hash=item469ae05387:g:qtsAAOSwhFZdSaor

Post-Script- I've had luck with AM 52mm cylinders sold by this UK based Ebayer _ https://www.ebay.co.uk/str/MENDASAW-LIMITED?_trksid=p2047675.l2563

Thank you...weirdly your post just popped up now; when I put the post up yesterday yours wasn’t there...so I’ve already ordered the expensive muffler

 

[KarlD]

An aftermarket 038 dual port exhaust isn't too expensive - this seller is UK based too: https://www.ebay.co.uk/itm/Exhaust-...103431?hash=item469ae05387:g:qtsAAOSwhFZdSaor

Post-Script- I've had luck with AM 52mm cylinders sold by this UK based Ebayer _ https://www.ebay.co.uk/str/MENDASAW-LIMITED?_trksid=p2047675.l2563

And I’ve already got this piston on the way https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/401241316246

 

[Mad Professor]

I’ve just ordered that muffler, save compromising the build by modding the old one badly.

I’ve also decided not to mess with the porting until I know a fair bit more...so the saw will be staying in bits until I’ve done some reading.

Reason for this is that minimal reading on here shows me that making a positive impact on performance is not as easy as just widening the exhaust port. When I realised I didn’t know what transfers were or what they did, amongst other things, I decided I should get a book first.

Thanks for the help and advice fellas, I will be busy for a while

Without porting it it is easy and worthwhile to polish the ex port. There will be less tendency for carbon buildup.

Concerning porting. There is a thread by Mastermind of a 038 to 038M conversion. He did a bunch of port work but that should be quite similar to what would work for a 038S.

You could live with the 038S as is, and look for a good OEM used 038M cylinder to port.

 

[KarlD]

Without porting it it is easy and worthwhile to polish the ex port. There will be less tendency for carbon buildup.

Concerning porting. There is a thread by Mastermind of a 038 to 038M conversion. He did a bunch of port work but that should be quite similar to what would work for a 038S.

You could live with the 038S as is, and look for a good OEM used 038M cylinder to port.

Thanks mate, I’ll have a look for the thread. I have found a bunch of threads about porting an 038, but most are so old that all the pictures have gone. Now that would not really be a problem if I fully understood the terms used in the posts, which atm I don’t hence the reading list. I’ll see have a look for the mastermind one tho and if there’s pics I’ll be away

 

[Teemore]

Thank you...weirdly your post just popped up now; when I put the post up yesterday yours wasn’t there...so I’ve already ordered the expensive muffler

My post was "Pending administrator approval for a while...." The conversion to Magnum spec is fairly straightforward.

 

[KarlD]

So now that my laser temperature gun has turned up from China I have split the crankcase; 200 degrees celcius and a few whacks with the mallet and job done...result

Can anyone tell me what this circlip is for? It will probably be obvious when I remove the seal on Sunday but I want to know now

Other side


Also, I think I need new crank bearings..


This weekend if I get time I will take a picture of all the new parts I have to refit during the rebuild...so that you knowledgeable lot can tell me what else I need

TIA

 

[Mad Professor]

The circlip locates the proper seating depth of crankshaft bearing clutch side.

 

[KarlD]

The circlip locates the proper seating depth of crankshaft bearing clutch side.

Nice...thank you. That saves me having to ask another question

 

[KarlD]

Well here we are, everything cleaned and ready to be re-assembled...once I get the crank bearings inner races off tomorrow. I don’t have a puller small enough atm so will carefully cut them off with my Dremmel. I’m used to fiddly little jobs like that so I’m 100% confident I can do it without touching the shaft.

 

[KarlD]

So...I have a few questions

1. The new piston came with new rings but when I ordered new Stihl piston circlips they sent me new Stihl rings instead. Should I use them or the ones supplied with the piston?
2. When I pull the two crank cases together I will obviously use the new gasket...but should I lightly apply some hylomar sealant or equivalent on both sides of the gasket as well? I’m thinking not but I’ve read plenty on here that says I should...
3. Should I omit the base gasket and measure squish, or should I install the base gasket and measure squish...or does it not matter?
4. What is the order of reassembly of the bottom end? I’m thinking (first time ever so be gentle if it’s retarded): -
4.1 - both crankcase halves in the oven
4.2 - both crank bearings in the freezer
4.3 - drop the bearings (lol as easy as that) into the crankcases
4.4 - both crankcase halves in the oven
4.5 - crankshaft in the freezer
4.6 - install the crankshaft into one half crankcase first and then pull the other half crankcase on
Dammit I have forgotten about the crankshaft oil seals...
Right guys tear into my jibber above, please tell me if I’m on entirely the wrong track or if I’m close.
TIA