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drifter 10-04-2010 01:25 PM

What engine is this? Sachs???
 
1 Attachment(s)
Can anyone identify this engine.
There is no name or identification on it as to maker or size.
The rear of the cylinder base says "Mahle"

It's about 7" tall and about 6" in length.
It has a Tillotson carb.

Any help appreciated

Antique 10-04-2010 02:02 PM

RE: What engine is this? Sachs???
 
One of the very best RC engines ever...
3.7 or 4.2 Sachs Dolmar chainsaw conversion...
Look on the base of the cylinder...a 4.2 will have a 49ZN case into it, a 3.7 will have 47 ZN..
It will outrun and outlast any Chinese engine ever made...Maybe not in WOT rpm, but any other category.,.
1000 hours cutting down trees is normal for these....In the woods...Using whatever oil the lumbejacks had on hand...

drifter 10-04-2010 02:22 PM

RE: What engine is this? Sachs???
 
Antique,
Thanks for the reply.
I was thinking Sachs because of the orange color.
There is nothing on the cylinder base except the letter "V" and "1 K" under that.

It pulled my 30lb plane around very well. I just have no idea what size it is.

Thanks again.

JLB 10-04-2010 03:47 PM

RE: What engine is this? Sachs???
 
Wow !! A blast from the past as I believe that's one of mine. I converted Sach 4.2's primarily for B & B who sold most of them for me. They were a great engine with plenty of power and durability and I built over a 100 of them. The majority of engines built since then with machined cases used the Sachs cranks, rods, pistons and cylinders until recently as we're now seeing different and cheaper internals showing up.

drifter 10-04-2010 04:48 PM

RE: What engine is this? Sachs???
 


ORIGINAL: JLB

Wow !! A blast from the past as I believe that's one of mine. I converted Sach 4.2's primarily for B & B who sold most of them for me. They were a great engine with plenty of power and durability and I built over a 100 of them. The majority of engines built since then with machined cases used the Sachs cranks, rods, pistons and cylinders until recently as we're now seeing different and cheaper internals showing up.

Thanks for the additional info regarding size.

Do you happen to recall the size of the prop bolt?

Andika 10-04-2010 07:41 PM

RE: What engine is this? Sachs???
 
Very good engines.. my father's 2T motorcycle was like this. http://www.rcuniverse.com/forum/js/f.../sad_smile.gif

http://fotos.sapo.pt/JCmtt788ELhKfvOd2jtm/

JLB 10-05-2010 01:21 PM

RE: What engine is this? Sachs???
 
Sorry but I do not. Nowdays I seem to be lucky to find my way home almost every time.

drifter 10-05-2010 01:38 PM

RE: What engine is this? Sachs???
 


ORIGINAL: JLB

Sorry but I do not. Nowdays I seem to be lucky to find my way home almost every time.
Thanks anyway.
Found out it is 5/16-24
The nut from my TT 120 fits perfectly.

STUKA BARRY 10-05-2010 02:49 PM

RE: What engine is this? Sachs???
 
That engine should swing a 22X10 or 22X12 three blade with no problem. Sorry, I cant help you with two blades.

drifter 10-05-2010 04:25 PM

RE: What engine is this? Sachs???
 


ORIGINAL: STUKA BARRY

That engine should swing a 22X10 or 22X12 three blade with no problem. Sorry, I cant help you with two blades.
You're quite right.
It turned a 22x10 three bladed prop in the 30 lb plane it was in.
Easy loops from level flight.

I just didn't know what engine it was.

cap10b 10-05-2010 07:08 PM

RE: What engine is this? Sachs???
 
Down here we used to call them "Orange Case Sachs" The old A&M engines was started by a man named Al Willart who took the orange cases and cut the motors out, cnc a back plate, added a spring start, his motors had the chrome or polished mag covers, add a prop hub crank that baby up and go fly. The first motors were 3.1, then 3.7, then 4.2 I believe he did make some 5.8's. Loudest and heaviest motor this side of hades. I think the height of the Orange Case sachs craze was at Bryons flyins, where J.W. Jones took one of AL's motors mounted it in a Zirolli P-47 and cranked that baby up and flew pass after pass after pass down the runway and everyone just dropped their mouths open at the sound. This was the first time anyone heard a prop rip like we often do now. Those old orange case motors in one of the Bud Nosen or Zirolli big warbirds was the cats meow back then.

Just a little vignette of Texas RC History.

JDS




Tired Old Man 10-05-2010 09:43 PM

RE: What engine is this? Sachs???
 
It's always good to remind people once and awhile that our foundation gas engines did not originate in China, Germany, or Arizona.

Antique 10-05-2010 11:02 PM

RE: What engine is this? Sachs???
 
Anybody in this gasser stufflong enough know that ONE of the very first gassers came from just outside PHOENIX Arizona...It was a 28cc forerunner to the Ryobi....Sold by Hobby Lobby...Had mounting lugs just like a glow engine and came with a long cast motor mount and exhaust header..It couldn't be hand started and came with a rope and pulley for starting...
It was also sold as a gas powered drill....Had one of the first, can't remember how long ago it was...
The big sellers were Canadian Quadras and Japanese Zenoahs...Only the best survived..

Super08 10-06-2010 12:19 AM

RE: What engine is this? Sachs???
 
...and the Canadian Quadra 42 became the US 41. I remember seeing my first gas engine back around '81 in a hobby store. They had a Zenoah and a Quadra. If I recall they were both around 20~23cc engines. I thought they were huge. At that time the biggest engine I had owned was a .61 glow.

Keefer 07-30-2018 03:59 PM

Similar Question on Sachs Domar - size?
 
Any chance some of you smart folks could help me figure out the size of this one? Other than some smudge blue ink, there's no markings that I can find.
Help?
Thanks!

https://cimg1.ibsrv.net/gimg/www.rcu...fe0451c457.jpg
https://cimg3.ibsrv.net/gimg/www.rcu...3ede0e666f.jpg
https://cimg4.ibsrv.net/gimg/www.rcu...fc50dc91ea.jpg
https://cimg2.ibsrv.net/gimg/www.rcu...61f5fcd7bf.jpg

CK1 07-31-2018 09:05 AM

It's for sure that it's a Sachs engine .You will need access to the face edge of the cylinder base flange to get the cylinder # . 44ZN is a 3.2 , 47ZN is a 3.7 and 49ZN is a 4.2 The numbers should be located just behind the flywheel shroud. You may need to unbolt the cylinder to raise it up enough to get to the numbers . I'm fairly certain its a 3.2 .

Keefer 07-31-2018 07:43 PM


Originally Posted by CK1 (Post 12451428)
It's for sure that it's a Sachs engine .You will need access to the face edge of the cylinder base flange to get the cylinder # . 44ZN is a 3.2 , 47ZN is a 3.7 and 49ZN is a 4.2 The numbers should be located just behind the flywheel shroud. You may need to unbolt the cylinder to raise it up enough to get to the numbers . I'm fairly certain its a 3.2 .

Thanks sir!
Odd to me that a manufacturer would hide their designators that way. I can easily pull the head on this one, but I have another buried in the nose of a 112" P-51. I'm not sure I want to go through that trouble to figure out the size.

Truckracer 07-31-2018 07:59 PM

The numbers are clearly cast on one face of the cylinder base flange. Not hidden at all. I’m not sure where they would put those numbers that would be easier accessed. Heck, most engines have no ID numbers anywhere.

Keefer 07-31-2018 08:08 PM

Ah - OK thanks Truckracer. When CK1 said "face", I took that as the mating face between the cylinder and the crankcase. I think I get it now and will take a closer look. Much thanks!

Truckracer 07-31-2018 08:54 PM

Whatever the size that should be a fine engine. Maybe carve a bit of weight off it and convert to EI and it will run rigjt there with most modern engines and with less vibration.

CK1 08-01-2018 02:33 AM

The numbers can in fact be hidden from direct view on the OE version of the chainsaw crankcase .The OE case obstructs the front view of the cylinder flange face , unlike the r/c versions with which the numbers are clearly visible from the front of the engine

r ward 08-03-2018 03:34 PM

what chainsaws would look for to find one of these to convert ? I live where there are abundant logging equipment and chainsaw repair shops/dealers and they all have old chainsaws laying round.

CK1 08-03-2018 04:29 PM

Dolmer saw used the Sachs and Mahle cylinders
Dolmer 115i for the 3.2 and a Dolmer 120 super for the 4.2 .
Dolmer 133 for the 5.2 and Dolmer 143 for the 5.8

bjb050 04-05-2021 01:31 PM

Sachs 3.7
 
Hi,
I have a Sachs that looks just like the one Keefer posted. I verified it's a 3.7 and found a guy to rebuild the carb. I got a new spark plug but am not getting any spark. I think there may be rust on the magneto, but I can't figure out how to pull that shroud off the flywheel to get inside and take a look? Any ideas?
Thanks
Bernie

Truckracer 04-05-2021 03:32 PM


Originally Posted by bjb050 (Post 12671836)
Hi,
I have a Sachs that looks just like the one Keefer posted. I verified it's a 3.7 and found a guy to rebuild the carb. I got a new spark plug but am not getting any spark. I think there may be rust on the magneto, but I can't figure out how to pull that shroud off the flywheel to get inside and take a look? Any ideas?
Thanks
Bernie

If like the one above, that engine appears to be an EI conversion as there is no visible mag coil. Maybe one of the ones that Ralph Cunningham did or something similar? The EI would appear to be behind that cover where the flywheel once lived. The cover should come off if you remove the prop driver hub. But just guessing as I haven't worked on that version Sachs before. Look earlier in this old thread and you can see the mag equipped version as the flywheel and coil are clearly visible.


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