Grainger Mcmaster supply MSG supply ebay

 

You will need a throttle kick-down solenoid and an unloader valve for the pump but be warned these can be a bugger to set up properly. You can use a centrifugal clutch in place of the unloader but honestly the unloader does not cost a lot and works a heck of a lot better than a clutch, which IMO don't work well at all on a compressor. If you are considering just a single stage reed valve pump then a clutch may be your only real option but that setup on only 6 1/2 HP is not going to produce a lot of air.


www.surpluscenter.com

www.surpluscenter.com/item.asp?item=4-1499&catname=

 

I was thinking this This and ither the 6.5hp Greyhound or the 13hp Greyhound or the Predator equivlants..

Where would I get the kickdown?

 

Not sure about that particular pump since they changed them a couple of years ago but the cast iron version of that one was a darn good pump for the price, I know of two of them that have been in service about 3 years and are performing well. For sure you will need the 13 HP to run that one because 6.5 would not be near powerful enough, you need over twice the power rating when using a gas engine vs an electric motor and three times the power rating is not too much!


Just an idea here, how about using an electric clutch controlled by a regular compressor pressure switch? You would still need an electric throttle kick-down and you would need to sync the throttle and clutch but that should be doable. Not sure how the clutch/engine would handle the sudden jolt of engaging such a heavy load as that compressor pump but if you use the unloader valve that's normally used with the pressure switch in conjunction with the tank check valve the the pump would be unloaded when starting, just a thought.

 

I was thinking about an A/C clutch. being I have the compressor from a '75 Lincoln. But the local small engine shop may have an electric PTO clutch kicking around.. Might possibly use the PTO drive setup from my '68 Sears Suburban 12hp. Just back the mower up till the belt was tight, and run an unloader valve... That reed valve pump would get hot tho

 

An AC clutch would be way too light but a mower clutch should handle the load.

 

Well, digging this post out of the grave. HF has there 212cc Predator 6.5 HP's on sale with a coupon for $99.99 and I ordered 1 to at least have that part. I'm also going to use the 2hp rated single cylinder pump instead of the 2 cyl. The extra $200 for the engine large enough for the 2 cyl wasn't worth it

Is This the throttle control I need?

 

Let us know what you think about the Predator engine, I had one of the Greyhound engines and not only was I constantly having to tighten parts that were working loose but the darn thing sure didn't last very long. It was used on my log splitter and after less than an estimated 35 hours (I am sure the estimate is very close) I thought the pulley was loose on the crankshaft but when I checked it out it was the crankshaft loose in the case! I still don't see how that darn thing was not leaking oil because it should have been pouring out as sloppy as that crank was, I could grab the end of the crank and flop it up and down at least 1/8"! The darn thing went to the scrap recycler and was replaced with a Honda.


What I have been hearing is that the new Predator engine is much better built and every bit an equal to the lower end Honda engines, it has a bearing on the crank output instead of running directly on the Aluminum crankcase housing like the Greyhound.

 

I'm not too worried. ok, the cam gear is plastic but $99 and I could always put an OEM GX-200 cam in if it broke

Lifan produces genuine Honda parts to ISO-9000 standards.

 

The new engines are 212cc, so I don't know whether they'll be legal for kart racing or not, but they're still rated the same HP so who knows? I got one for my mini bike, so it doesn't matter to me, but for racing I'd want to check.

Word has it the stock flywheels will come apart if used ungoverned. Not a problem if used for a log splitter or compressor, thankfully. Iron cylinder liner and ball bearings on the crank. About as good as it gets for a clone of the Honda. 'Specially for a c-note.

 

word is there not legal for kart racing, and only 196cc engines remain in class.

Honda flywheels fit and NR racing has them cheap.. I'v also found the cams are not interchangable with any other engines except LCT cams are listed to interchange. NR racing has a stock class cam which is all steel.

 

I should have added that there are both cast iron (cheap) flywheels available as well as aluminum ones (not as cheap).

 

212cc Predator 6.5HP

The link below has them calling the 212cc Predator 7 HP. They also seem to be a little concerned about using ZDDP because of the flat tappets. Personally I do not thing there's enough spring pressure to worry about it.

Seems that the Predator has different rods, cams, and piston/rings than the Honda GX 200 and clones. The 212 cc Predator has a 70 mm x 55mm B/S, the old engine was 68 mm x 54 mm.

5 reviews are available- http://www.harborfreight.com/Predat...adv=40010&mr:trackingCode=5CC66A02-2336-E011-8262-001B2163195C&mr:referralID=NA

From HERE:

 

yep, the piston rod and cam as non interchangable is what I have come across also.. dunno where the 7hp comes from. HF lists as a replacement for 6.5hp but doesn't give an official rating in the manual

http://manuals.harborfreight.com/manuals/68000-68999/68120.pdf
there are some other pics on 1 of the karting forums.. they actually look quite decent

 

Another question.. being the HF pumps are single stage reed valve pumps, can they run continuous or do they need to shut down?.. reason I ask is I found the right unloader valve and kickdown, and the right size pulley to obtain just under the 1,100 RPM. But also found a centrifugal clutch with the right size pulley. with a regular gas unloader valve, I'm not sure how to make the pump unloaded for starting if I went that route. the diamater pulley I need is 3.67" calculated, and the cent clutch is 3.7", so it should be very close to perfect..
I'd like to go with the $8 pulley if I can tho. clutch is 10 times more money

 

Several unloaders here that are not dependant on the pressure switch- http://www.airtekltd.com/valves.htm

I'm not sure why you would have the compressor pump running constantly, but there may be a duty cycle rating- although I don't recall seeing anything like that before. I'd imagine the pump could run continually as long as the temperature wasn't excessive.

When all is said and done, is the engine going to go to an idle after the tank is full, then kick back up to speed when the pressure falls? If that's the case you will need a centrifugal clutch, unless you want to hand crank it every time.

 

If the pump is belted directly to the engine with no clutch, the pump spins all the time, and normally gas compressors run 2 stage pumps which are designed to do that normally anyway... But both of the HF pumps are single stage reed valve pumps which would normally fully shut down with the electric pressure switch and an unloader..

My setup will use a continuous run unloader designed for gas compressors, and has a port to operate the throttle kickdown.. But I'm not sure if a reed valve pump should continue to spin even at a reduced rate. theres a big diffrence in price between the pulley and the clutch

unloader valve

throttle control

But if it needs to shut down and I use the centfifigul clutch, I don't know how the pump head will unload, unless the vent will fully unload the compressor head.

 

Both of my compressors I have now, and all that I've ever had for that matter, were start and stop, not a continuous run, so you're into an area that I have zero experience. But my gut tells me the pump you have will not want to run continuously. There's no duty rating to it?

Unless I've missed something, the 'Load Genie" will unload the compressor at shut down for an easier restart.

 

It doesent have any duty rating listed, only that it's recommended to run at 655 RPM or 1/2 of it's max speed under most conditions. I would run it at max speed to get the 10 CFM@ 90 PSI, being it is not going to be used as a main compressor, only when I need more air

 

Normally driving the pump directly from the engine is the best way to do this and that's why factory gas compressors are set up this way but with that pump doing it that way may be a bad idea. I am about 99.99% sure that type pump is going to be splash lubricated which means it likely will not get enough oil while running in idle so you may be stuck with using a clutch for that reason. Rigging an electric clutch would be best but it can be really tricky to get it to work properly since it has to be synchronized with the engine coming back to speed from idle, if it kicks in too soon the engine can stall and if it kicks in after the engine reaches full speed it can be a really heavy jolt to both the clutch and the engine. A centrifugal clutch will solve that problem, will be cheaper and will be MUCH easier to set up properly. The downside is they tend to not last very long if the compressor is used a lot. Whichever you use you will still need an unloader for the pump and a kick-down actuator for the engine throttle and don't forget the backflow valve in the tank.



Cobalt, just a note about the Genie unloader, all piston compressors electric or gas (well all conventional compressors anyway) require an unloader to reduce starting torque and come from the factory with them already installed. In fact unloader failure is one of the biggest causes of electric compressor motor failure.

 

Min operating on the pump is 655 RPM, and at the 1,800 RPM idle that the engine is rated for, comes out to 532 RPM so it wont work. looks like a cent clutch is what it has to be. the 1 I found is rated for 13hp, it should last ok on the 6.5-7hp engine. It's smaller than the optimal size, and will run the pump at 864 RPM, but that's splitting the diffrence anyway

http://www.mfgsupply.com/gomini/gom.../gomini/gominiclutch/gominiclutchutility/gominiclutchutilityhilliard/h34p3.html

 

with a gas powered compressor you'll probably want it to run continuously when your using it. if you have to start it every time you need more pressure, it will get old very quickly. i know it did for me.

have you thought about getting one off craigs' list?

 

It will run continuous, just the throttle control will idle the engine during the time it's within the pressure range of the unloader, and with the idle, the clutch will allow the pump to stop as it should being only single stage..

I'v considered buying used on CL, but every one I find that's in the range of what I belive I could build this for ( $350ish ) I find looks like it's been stored outside or just plain abused.

 

i know you were talking about the continuos run time of a reed valved pump, i believe most of them are reed valved and use a slinger for lubrication.
i don't think single or dual stage really matters that much as far as run time goes.
if i can remember, in the next day or so i'll try to pull the module number off the compressor in my work van and look up a break down of the pump.

im not sure if an electric PTO clutch from a lawn tractor will work.
the mower deck belt does slip when you engage the clutch.
on a compressor with such a short belt, there won't be much if any slip.
i guess it could be worth it to try if you can get a used clutch for really cheap. i know new they are not cheap.
you'll need a pretty big pulley on the pump to get the RPM right.

most of them got stuck in the back of a pickup, so they can get to looking pretty bad.
aren't you in New York?
if so, this one may be worth a look, for parts if nothing else.
http://rochester.craigslist.org/tls/2722668044.html

could buying new be an option?
http://www.sears.com/shc/s/p_10153_12605_00931307000P?prdNo=1

to bad you can't run across what this guy did,
http://www.youtube.com/watch?v=UeAzZ3rj7K4

 

With the 12" pulley on the pump it comes with and the 3" clutch pulley, rpm comes out to 864 RPM, which is below optimal but above reccomended running speed of the pump..

Harbor Freights smaller 212cc gas compressor pump does seem to use there 3 hp pump that they sell for $139, so it may be safe to run it without a clutch.

I'll have to take a run to sears or HF to try to mimmic there setup.. Rochester is quite a drive for me, and for $600, I could buy 1 of the HF 220v electric models and run it with the 5k watt generator