OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Tech Talk Sachs made a Wankel engine lawnmower in 1972

Well I have been wanting to know about the Sachs made a Wankel engine lawnmower from 1972.For quite some time,manly as I would truly love to have one.I guess the biggest problem with that is I don't think he had them in this great country of ours.I mean how great would it be for a mower collector (Me that is) to have a rotary powered rotary? For those that don't believe me here look at these.


Also a you tube link or 2:



I've try doing research on the net but all I can really find out is, Felix Wankel the German engineer,whom came up with the idea. So if anybody knows anything about these,or even better if they can get hold of one that would be great.I like them a lot.Would love to have one.

The Wankel rotary engine has been used fairly extensively for two purposes: as a compact portable petrol engine for items like generators, small off-road vehicles, etc., and as an automotive powerplant. The first production cars I know of that used this engine were the NSU Spider in 1964 and the NSU Ro80 in 1967, but they were followed by a long series of Mazdas, starting with the Cosmo in 1967 and the R100 in 1968, followed by the whole RX series up through the RX7. I can recall test-driving an R100 when they were first produced, and being underwhelmed - I've never driven another car with as much clutch slip when power-shifted. Also, the Wankel engine was very smooth but severely lacking in low speed torque (which was probably the reason Mazda expected to get away with the inadequate clutch capacity).

At one time General Motors and many other car makers took licences to make the Wankel engine in huge numbers for small cars, but at almost the same instant, emissions controls became mandatory and the concept became undesirable.

I think the Wankel engine is now only found in applications where fuel efficiency, durability and exhaust emissions are less important than light weight and small size. Portable generators to be air-dropped by the military might be among the more important examples. It would be a bit expensive for a lawnmower, and rather a pain to overhaul, but otherwise that is probably a reasonable application. Sachs has been making Wankel engines for decades, selling them as multi-purpose powerplants in the same way as Briggs and Honda sell small engines.

That maybe true but [bad word] I want to find one. I wonder if there are any in Australia?

The engines can be found easily enough in aus from the mower, I have a couple of mates that have one each,

Every NSU RO80 I have seen has been fitted with a mazda rotary at some stage of their lives thanks to reliability, interesting car, inboard front disc brakes, an a rather odd clutch/gearbox arrangement.

I had an rx7 at one point, it was all fun and games until it let go of its apex seals in a rather spectacular fashion

The original mower manufacturer was Arctic Enterprises, you can read an early report on the mower from 1973 here:
http://books.google.com.au/books?id...tary%20engine%20lawn%20mower&f=false

Here is their calalogue advert, showing 4 models of rotary push mowers, produced in 1972,1973 and 1974 model years:
http://www.bosscatlegacy.com/acproto/tractor/acprotonstrac.htm
It appears from the catalogue that most of the mowers were painted an extraordinary shade of puce. A remarkable marketing decision, I would say. Perhaps there are even more transvestites in the US than I had previously thought.

The engine was a Sachs/NSU KM3. I've read two reports that the mower was a disaster in some countries because the coir matting air filter element was ineffective, resulting in extremely rapid engine side-plate wear. One report said this happened in NZ, the other said it happened in Australia. The NZ report was more detailed and was a first-hand report. I also found several reports that the ignition coils on those engines were very unreliable.

Here is a 2007 report by a person who owns one of the mowers, and the report by the NZ person who said the engines wore out their side plates very quickly:
http://forums2.gardenweb.com/forums/load/lmower/msg1016374624654.html

So, most likely the mower was sold in NZ, and very likely it ended up being held in low regard. Perhaps you can find one for sale in NZ.

Awesome work grumpy well done.I'm glad I asked now I have been looking for weeks and didn't even come close to that much info.Thanks grumpy,now to start the search for one.

A rotary mower how cool is that now all it needs is a Bridge Port!...I will take two thanks...

Hi Chris125,

Bridge port would be pretty cool, The First thing I thought of was the full peripheral port job when I saw the Rotary!!!

Had an RX4 coupe once....wap wap wap wap... It was cool to pull up nxt to someone @ 110kph and give them the gearbox count down from 5th to 2nd and then take off.... 90-95mph was its comfort cruise speed but melted/burned out extractors at least once a year.... if I was "nice" to it

Would be great to get one as a curio for sure.... I wonder if anyone put one in a kart? They seem to have not found favour in a mower (for good reason), although my old man would like its low profile for pushing under shrubs when doing a utility type yard clean up.

Apparently they didn't have a lot of torque,but I guess that just goes with the hole setup of the rotary,but they were smoother than a piston engine.
Here are some more pictures of them.







I would love to be able to get one.How great would that be?

Your right, a rotary engine is poor for torque and speaking for the 13B very smooth running, I liked them for a while. (so did the petrol stations, exhaust shops, brake shop etc.)

Geeze they get a bit tall after you put on the fan etc. so much for the low profile!

Have you tried a NZ site as per grumpy's suggestion? know any Kiwi's?

I have a good Kiwi site etc. somewhere, I'll have a look over the nxt week or so, and seeing a Kiwi expat over the break (who goes back on occasion), I'll ask...

Merry Christmas Mr. Blumbly

Cool thanks Fast Grass.No I haven't check any NZ sites yet.Hopefully will get some time over the weekend.I know this is going to be a hard search but [Censored] I want one now.There has got to be one somewhere.
Also a Merry Christmas to you and all your family and friends.

Ahh yes I forgot about this post ... I asked around and spent a bit of time with an expat Kiwi he reckon's the thing to do would be to get onto the NZ Govt. / business exporter's list? and ring around to see who has a container coming to your part of Aus. I reckon you could get a couple of mowershops close to port to send you a trade in or put a wanted post up on a NZ mower site or NZ Ebay / Kiwi (gum) Tree etc. My Kiwi contact reckons that you could probably get it in a container that was not full and sent for nil$, might cost you a few beers at the Kiwi end but...who knows you might even find a few "export twins"

OK cool thanks fastgrass that my be something I need to look into.Don't suppose your friends knows of anybody there with one?

No worries Mr Blumbly....... er he didn't seem to keen to talk mowers, (he didn't give a tinker's cuss about them) so I had to hold his interest on other matters to get this suggestion. Good luck! Check those NZ sites out mate, I've lost my bookmarked one some how.... I'm sure you will find a keen Kiwi!!!

OK will give it a shot. After all I have no other ideas.

I own one of these rotary mowers its a sachs km3 about 1972 on a masport body of around the same year. i have done a port job to ova lap the intake and exaust this gives it a pulse it screams with flames owt the exaust i wouldnt call it a bridge port because these are a 2 stroke set up with a percentage of ful air mixs cums thru the crank case witch has roller bearings i dont know how urd get away with a pp port bcause of this i love using mine and would only part with it 4 the rite price or id rather hold on to it with my collction it so cool.

Wow, those are really cool, I believe they were sold in the US for a short time, though they looked nowhere as nice as those machines there... the obly picture of an American model I ever say was large and boxy and was as ugly as could be expected.

Kori

Well that's cool. I guess it all depends on what is the right price. If you have an idea of what price you want then send me a pm. Other than that please keep your eye out for one for me. I'm not sure I will be able to find one here in Australia there were defiantly more of them in New Zealand. So if you could keep your ear out that would be great. Let me know how much you would like,kind of sounds like you are attached to it. So you might be too high for me,but lets see anyway. Thanks wayde.

yea this is the only one iv eva seen i actulay got it from the dump sumone wouldnt of had any idea ha ha

Yes it just makes you wonder how many are in landfills.Have you got any pictures you could pop up here?