All I know about the Wen-Mac Kart

I like the looks of the engine, similar to the Atwood Wasp. I know some parts interchange. I've never been successful with my version of these engines to use them. They're very problematic to start. The venturi is suspect on mine. It's extremely small and would offer reason to the engine's anemic state. I find these engines flood extremely easy rendering starting very difficult until cleared. This would be the cause for any engine, the Wen-Mac has me reaching for the sledge hammer. I don't own the Rotor-Matic versions as mine are strictly air. I also know there's a few different versions of these engines usually depicted on the case by numbers of the series. I also believe there's the thinnest paper gasket under the cylinder known to man. If this gasket goes, fuel draw and compression is compromised.

Thanks Robert and Ken

I haven't seen the Ok version Robert, you have me looking.

And Ken the "Roto-matic" version is quite easy to start, in fact it's the best starter that I have seen on these small engines.  This one has a standard aluminum glow plug gasket.  I did not remove the head or backplate.  After Berryman's and hot soapy water/alcohol rinse it's clean and functions perfectly.  Why tempt fate.I have had bad experiences with these removing that backplate...........it ain't easy!!!!

Typical castor goo, got under everything.  I just dumped it in Berrymans and painted it on, let it sit for about 15 minutes and washed it off with warm soapy water.  Rinsed and dried.





Mounting posts for the engine module were broken, I saved one and replaced the other with posts that Jason made for me years ago.  



Engine cooling fan is strange.  Red plastic is made up of two parts and spin independently.  Flywheel is solid steel and heavy.  Cox wrench specially drilled to accept the larger Wen Mac shaft.

getback wrote:The fan looks like one that would catch air and spin with a force out the back for cooling ?/ Interesting that its independent from the CS .    That is one bigun all i can compare it to is the Prop Rod  Cleaning up good !

Thanks Eric, it's a work in progress.

And Robert.............Wow $749.99 A little out of my comfort zone. Cute though. Must be the engine and rare, the W/M blows it away for complexity.

https://www.ebay.com/itm/305150647035?hash=item470c655afb:g:0e4AAOSwoyxlC7-L&amdata=enc%3AAQAIAAAA4JlwupSt%2BvrvtDg2pjBbpt694EFp0EpaG3%2Fo9a0wNy2em%2FH%2FcXRkyaUYZFPo2KTCIGnNgwoyyKggMIcyBW2SVM01fHNdVt9ca9N04rG3ja%2FX%2BFWg18eWmeVUbc2ku5dK%2BPhFyUNwVuFJNz5MMIH3Ej9IroPF1PssF%2BfqficBqOEiz6A1TrxsNfpBWN8VYaVOA44vK1f8eI203fQoXQCfbkYwq6uc2v7DppQSBy3%2FI%2FKi45EWpLyw2iVHlaX%2F18AZHA6s%2B8uyb93M7B5OVv3LqQ%2BfA0jtIim%2Fd5hjzyf7%2FJ3o%7Ctkp%3ABk9SR_zInazhYg

getback wrote:I have seen a few of those on the Bay that's Hi usually around 350 will get you one

I was just looking on ebay for the part on the W/M Kart that I'm missing. I guess it's this steering mechanism.

Mine



ebay offer



Bad part is - it's connected to a partzer sale.  $100 or make an offer.  I made two $75 and $85, both declined.  So what..........I bit at $100.  Actually it's complete minus the second red foot rest.  Looks like the seller bought/found the replacement part to fix the broken steering mechanism presently on the Kart and never installed it.  See the broken off red foot rest.

When I see plier marks on a cylinder it makes you want to just punch someone in the face.

Ken Cook wrote:                 When  I see plier marks on a cylinder it makes you want to just punch someone in the face.

Agreed!!!!!!!

Especially on this one.  Beer barrel cylinder with a standard glow plug.  Very strange in W/M world and I haven't seen another one.  I wonder what Mk it is.  Anyone?

Bob, I think you have a hybrid there. I mentioned above about the ability to interchange with Wasp engines. Your engine certainly appears to have a Wasp cylinder head on it.

Ken Cook wrote:Bob, I think you have a hybrid there. I mentioned above about the ability to interchange with Wasp engines. Your engine certainly appears to have a Wasp cylinder head on it.

That is interesting, so it is possible for some parts swapping. I searched the Sceptre Flight engine archives, and couldn't find a beer barrel cylinder fin Wen Mac.

rsv1cox wrote:

Ken Cook wrote:When I see plier marks on a cylinder it makes you want to just punch someone in the face.

Agreed!!!!!!! Especially on this one. Beer barrel cylinder with a standard glow plug. Very strange in W/M world and I haven't seen another one. I wonder what Mk it is. Anyone?

I have found by carefully swedging the raised dimples with a smooth jaw needle nose or duck bill pliers, then carefully dressing with a file will make those look less noticeable. Also, the flaws may contribute to a drop in value, which means the item sells for less, which can make it fit one's budget.

I've done that to a couple engines, cylinder cooling fins and aluminum prop thrust plates. After dressing, they don't look as bad and helped to restore their looks with a sense of usefulness.

If it is too pretty, then it is less likely to be used.

George, I believe the Holland Wasp used what you refer to as the beer barrel head. I have both and sometimes the engines even had a H designation on the case to dictate Holland. The Atwood used a head which was more of a flat on the top and head tapered, this would be similar to the Wen Mac. Mark Bosen has shed light on this over the years. There's several variations of these engines. I own two of the Atwood Shrike .049's and these also have a beer barrel shaped cylinder. The head on the Shrike was a one piece glowhead which changed .049 power forever.

It will be interesting to see once I get it, should be soon as it's pretty close in Virginia.

Finished the Kart.  Engine has a nice compression pop, I cleaned out the fuel tank and added new fuel line saving the original nipple.  No more castor goo.  Added the missing steering column. Ka Bob Skewer painted yellow.  Looks only the front wheels do not turn, solid axle.  Has a bridle, but also fixed for straight-line string operation.



Now where to place it.  This thing is out-sized.  Won't go North/South.  I had to lose the Sandblaster and a Prop Rod to get it to fit.



Now back to repairing the Cox Army Locomotive (someone installed the trucks backward) and pay some attention to the neglected profile P-38.

getback wrote:I think Ken is right from what i have seen they came with the MARK V engine >>  https://www.worthpoint.com/worthopedia/gas-power-jr-kart-amf-wen-mac-parts-1814936449 and that don't look like one > https://www.ebay.com/itm/295807364241  

Eric, from your first link:

Ebay photo.

The aluminum cylinder fin cover for the sleeve is slightly tapered, but definitely not beer barrelled.

Here's the same model Mark V engine in a photo that is a bit clearer:
https://www.ebay.com/itm/235162019850 AMF Wen Mac .049 Mark V - Vintage Model Airplane Nitro Fuel Engine


Ebay photo by seller jmc-go.

Yes, the standard Wen Mac engines cylinder is "top heavy" where the engine is question is tapered at the top. Unusual.

In the past I have using the glow plug chucked it up on the drill press and used a fine jewelers file and 400 grit paper to remove the tool marks. Not sure how or if I will deal with this one.

I am more of a perfectionist, so I can get by with various hand files, emory boards, pliers, etc. without turning the cylinder to true the fins. Each has their preferred methodologies and practices.

I'm just amazed Bob, how you are able to turn sow's ears into silk purses.

Mystery engine:





Things that make you happy.  For most it's a night out or a new something.  For me it's something old and beat up.  With this second Wen Mac Kart it was like Christmas.  Seller had wrapped each piece individually in bubble wrap.  I smiled as each piece unwrapped seemed worse than the piece before.  

Worst part is the engine mount, all four mounting posts are broken off.  I will have to make a new one out of wood and join it with the fuel tank whose fuel nipple happens to be intact, rare for these.  





Cox Semi trailer came at the same time, axles broken along with couplers. It's ok I have a NIB coming.  The Kart is more complete than the first with the steering shaft and a mount to lift the rear end off the ground for starting/running.

Cleaned the cylinder up a bit. Drill press chucked up using the glow plug. Spun with 100 grit w/d paper, then 400/800 and fine steel wool. Went as far as I dared but got rid of 90%. Still needs some detail work.

Great photos and article Bob!

Yep, its a Wasp Head. LMK, if you need a good one?

Mark Boesen wrote:Great photos and article Bob!

Yep, its a Wasp Head. LMK, if you need a good one?

Thanks Mark.  Maybe, I'll let you know.  Meanwhile............

I have a bid in on these two gems:




Check the cylinder on the left and the V (5?) marks.....................Very similiar to the Kart engine.

lol, are they paying you?

yep, that's odd to see Atwood head on a Wen-Mac twice like that...