Compressor pump engine

motorhedfred said:
Ok, remember my ramblings about turning an HF v-twin compressor into an I.C. engine ? Well..... I was shopping Craigslist and found something interesting. It's a 90 degree v-twin compressor with 1.75" bores and 2" stroke. It has nice round cooling fins on the cylinders and plenty of them. I bought it and the pics are here....

Bicycles and BTRs pictures by motorhedfred - Photobucket

There's a nice big tapered roller bearing behind the round plate on the side. The crank and rods look plenty beefy, but I doubt I'll be able to use the heads. The motorcycle in the pic is my 250cc Hyosung. I put the compressor pump in front of it for size reference.

I would like to try automatic, atmospheric intake valves and exposed rocker arms for the cam driven exhausts.

Should be a challenge.

MHF
Click to expand...

This is what I'm up to.
 
I'll definatly be watchin and participating in this thread! I want to make my 3 cyl Speedare run.
View attachment 42200
I have seen some utube clips where compressors were converted into engines. Hafta go find those again and study them. I saw them in some of the clips that showed homebuilt mini v-twins ect.

I have an old air cooled Fuller and Johnson pumpjack engine that has atmospheric intake valve, to study for design ideas.
Wouldn't be hard to modify an old 6 cyl tractor magneto to be chain driven for old school lookin igniton.
Gonna be looking hard at all type small engines too. Might find some heads that can be retrofitted.
I jacked this pic from the other thread. I want to try for something like this.
'09%20Curtiss%20.jpg
 
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I must be wording my search wrong on youtube. I never found any vids for this. I was wondering the same thing about adapting heads from other engines.

MHF
 
Somewhere in the dark past I saw and early engine design with and atmosphereic intake and an exhaust port. Is this possible or am I just remembering it wrong. Seems feasible. I guess there would be some fuel lossage at the bottom of the intake stroke, but maybe no more than the early 2 strokes. If this works, would make a compressor conversion pretty easy. I doubt it would be a real popwer house, but if it would putt-putt a bike down the road at 10-15mph would still be pretty cool.
 
cannonball2 said:
Somewhere in the dark past I saw and early engine design with and atmosphereic intake and an exhaust port. Is this possible or am I just remembering it wrong. Seems feasible. I guess there would be some fuel lossage at the bottom of the intake stroke, but maybe no more than the early 2 strokes. If this works, would make a compressor conversion pretty easy. I doubt it would be a real popwer house, but if it would putt-putt a bike down the road at 10-15mph would still be pretty cool.
Click to expand...

Tht description sorta matches the old Fuller& Johnson pumpjack engine I have. It has an atmospheric intake, and an exhaust rocker like most of the engines of the era. But it also has an exhaust port that opens at the bottom of the stroke. Some think this extra port was to let out more exhaust (and heat) than just the valve would during ex stroke, to aid cooling this air cooled engine.
 
That looks like a good candidate. It appears to have a massive cast iron head that may be easier to retrofit poppet valves and ports than my Speedair heads.

The 5.2 number in the model # may be reference the volume of the cyl. 5.2 cu.in.? 520 c.c.? Just a guess.
 
I like that one cannonball2. The fins on the ports and the way they're already pointed out to the sides make it look a couple steps closer to an internal combustion engine than mine.

I "googled" Schulz, MSI, 5.2 and came up with this....

Single Stage Compressor Pump MSI 5.2 ML -

If you plug the cylinder size number (I assume they mean bore size) and stroke length listed into the bgsoflex.com displacement calculator, you get 4 cubic inches or 64.8cc.

Looks like they've got some parallel and V twins too.

MHF

P.S. Wayne Z, I looked up a youtube vid of a Fuller & Johnson pumpjack engine and the head is what I originally had pictured for the valves and ports if you imagine some cast iron pipe tees screwed into the heads with a bronze plug in them. The bronze pipe plugs would be drilled to accept the valve stems.
 
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OK, I think I found a head that could be retrofitted to the Speedair compressors fairly easily. I took this off of a chinese 3kw genset with a bore of 68mm. From the outside it looks almost identical to the 99cc and the 212 HF engines heads.
IMAG0112.jpg

IMAG0111.jpg

The bolt pattern on my Speedair is 2.5 x 2.5 "
The bolt pattern on this head is 2.5 x 3.25".
After the rockerbox and other extraneous material is sawed away, new holes could be bored to get the 2.5 square pattern.
 
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Wow ! That's exciting news. Thanks Wayne. I wouldn't have thought they'd be that close. Maybe one or both of the head bolt holes that don't line up could be used to pass pushrods through.

I've been trying to come up with a way to keep both exhaust ports to the outside of the vee and intakes in the middle ala HD. I think the cam problem would have to be solved by a lobe for each valve, with one cylinder's cams rotating opposite of the crank. My pump has the 4 bolt cover on the side that holds the race for the tapered roller bearing. I'm probably going to have to have the end of the crank slotted to drive a gear or sprocket for the cams.

If you've ever noticed, a Sportster has parallel pushrod tubes while the big twins converge at the bottom like a narrow V. This is because a Sportster uses a gear for each valve. I've seen stock Sportster cam sets fairly cheap on eBay. Planning on sniping a set soon for a trial mock-up.

MHF
 
You could probably easily reverse use the ports on one head and work OK . One cyl would have different power than the other because of reversed valve dia, but it prolly won't matter much.
If ya really want to, the heads could be machined for larger seats on the exhausts and then the power from each cyl would be even.
 
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I have heard that some of the small Honda industrial engines have a cog belt driven overhead cam with only one lobe for both valves. How'd they do that? Maybe one could study that and make one lobe work for 2 cylinders?
I saw where one guy on utube converted a v-twin compressor. He modified the crankshaft to have a stub that extended thru the rear bearing case, to drive the cams.
 
A few weeks ago I bought a vertical shaft Honda GCV160 powered pressure washer for $25. The guy had left the washing fluid on it over the winter and it froze, ruining the pump.

Apparently, that happens a lot around here as there's always a few on Craigslist. A replacement pump, or a repair job costs almost as much as buying a whole new washer, so people sit on the ruined one for a while, then realize it's just taking up room and they sell them.

My intention is to mount with the shaft horizontal. That puts the carb in the rear and exhaust in the front. The nice round mounting flange looks BTR-ish and it's bolted to a fairly thick plate on the washer cart. I plan to make a template the size of that plate, mark the chassis tubes on it and cut the mounting plate to bolt 'er in. I'll do this first to get a motorized bike rolling while I work out the details on the lil' twin.

As to how the single lobe works 2 valves....it's similar to my old 4-stroke pushrod Ryobi 26cc wacker engine. There are 2 rocker arm/cam followers that contact the lobe about 45-60 degrees apart. Depending on their pivot point and clocking locations, they either push down on a valve tip, or up on a pushrod. On the Ryobi, the arms are shaped like this Γ˚ and on the Honda, like this ˚Γ. On the top horizontal leg, the dot represents the pivot point and the other end does the work. The bottom of each vertical leg has a follower that rides on the cam lobe. There's a mirror image of these for the other valve in each engine.

I wish I could explain it better in text, but there's nothing in the Windows character map that looks any closer. Imagine a traditional cam lobe shape rotating inside a pair of mirror image upside down capitol Ls and I think you'll get it.

Honda GC160 Parts List and Diagram - (Type QHAJ)(VIN# GCAH-1000001-9999999) : eReplacementParts.com

Look at page B and study the parts diagram for the valvetrain.

MHF

P.S. is this the compressor engine you're talking about ?

Double the R.A.G.E. - scale V-Twin model Engine (Homemade) - YouTube
 
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