Wacker GVR 151Y jumping jack compactor info

Hey all, this is a mostly informational post, as a web-resource for future old vintage Wacker packer owners. I found shockingly little info when I Googled up this machine to find out about its engine, I think due to its age (1960s) and lack of support, and inconsistent manufacturer naming. I hope someone finds this and it’s helpful. It took several days of websurfing and tear down to gather this info.

Boiled down, the older Wacker compactors (GVR 151Y) and other variants (GVR 100Y) have engines that are some form of West Bend 580 engine. This is a 4 hp 2-stroke, air-cooled, Reed valve, cross flow/scavenged, with points ignition. Most of them on jumping jacks have a yellow flywheel cover/shroud, and have rounded head shape/ fins and a cylinder jug that is integral with the top of the crank case and a centered top spark plug. Usually a Tillotson pumper carb is stock. They should have between 90-100 psi compression, but mine is still kinda running at 50 psi. Hence the reason I’m looking for rebuild options.

Many Wacker jumping jacks made after the GVR series and before the current production models, come with a WM80 model engine (the BS series of compactors ). Often with a grey colored shroud, and squarer head fins, this is still air cooled, but slightly different design to have a more stuffed crank case and I’m sure a few more mods for performance or reliability or maintenance. Parts and info for the WM80 engine seem to be plentiful so if you can get one, it looks to be possible to retrofit to a GVR. The nice thing is on the WM80 has a separate cylinder jug that can be removed so you should be able to do a piston/ ring job in place, and not touch the crank.
Back to the 580, the 580 name comes from 5.8 cu.in., or around 95 ccs displacement. And the 580 is usually somewhere in the engine model number engraved on a plate riveted to the engine, except in my case which had had the plate removed. But what is less obvious is that Wacker ( not West Bend) might be listed on the plate as the brand of engine, and the model number was 58057, or 58049, or similar which don’t get you to any West Bend parts lists on the web, because they’re too specific, not just a 580.
Also, since the company that made the engines changed hands several times over the years, it could’ve also been made under / named Chrysler, Chrysler Marine, US marine, Mercury Marine, or Power Bee. And many of these brands parts are compatible, if they are 580-based parts. The West Bend 610 and 8XX are not compatible designs directly. The West Bend engines were often used in outboard boat engines, go karts, chainsaws, and even Rokon mini motorcycles, if I’m not mistaken. New engine parts (besides gaskets) don’t seem to be available, but new-old-stock pistons, rings, cranks and cases come up on karting/mini bike/old engine forums and eBay , so keep an eye out there. Rebuilt engines are seem to be aimed at novice or non-mechanic karters, and are $500 or more. But the NOS pistons and rings were only about $50 each. I’ll include a link to this one mini bike thread was super helpful to me.

Maybe someday we’ll find a compatible piston or ring set we can get readily off-the -shelf! What’s crazy is that it seems full jumping jacks of this age are being sold for about the same price with an engine.

As far as the jumping jack hardware (non engine parts) itself, I have found primarily the corrugated boot/bellows available new for this jumping jack, but the metal foot-plates are around and there are only sometimes parts popping up on eBay, but not much else newly manufactured any more. With that said, most of the internal mechanisms are fairly robust and don’t wear if you keep oil in it, and dirt out. I even think my boot/bellows only cracked and failed because the carb was leaking and dripping on it for months before I got it, and the gas exposure ruined the rubber bellows. The green bellows PN is 1006882 , also common with WACKER BS60 BS70 BS600 BS650 BS700 DS70 DS72 And more.

More to come later!