New engine, 79cc predator for high mobility air compressor

[oil pan 4]

I haven't fired it up yet. I'm rebuilding my ancient 5hp Briggs flathead air compressor to be lighter and easier to move and easier to start. The old flat head needs a squirt of carb cleaner if I want it to a least pop on the first pull. It really really don't want to start when it's cold during the winter.
I'll probably sell the old flathead it on fb marketplace.
The predator 79cc has a foam air filter, I'll be spraying that down with K&N air filter oil to keep the dust out out of the engine.
For break in oil I figured I would use the sj rated STP oil they sell right next to the predator engines.
The engine doesn't have provisions to attach the unloader bullwhip to the throttle lever, but I should be able to figure it out.
I'm putting a smaller lighter air compressor on those tanks too, HF used to sell an aluminum body, head and pulley compressor years ago, I made an electric air compressor out of one. I'll poach that compressor off my electric and replace it with a cast iron one from HF. That aluminum twin cylinder compressor can still be found on the assembled wheelbarrow air compressor they sell currently.
So for break in oil changes I'm thinking change the oil a 1hr then again at 3hr?
Has anyone used any of these 79cc predators? What are they like? Easy to start?

 

[Ausfahrt]

I don't have any experience with the 3hp 79cc engine that you have but the larger Predator engines that I bought have been solid. The idea of repowering old equipment to keep it functioning as intended appeals to me and applaud your efforts.

Are you concerned at all about replacing the original 5hp engine with a smaller one? Any pictures?

 

[meep]

I had a smaller predator engine, one of the few I’ve heard of with problems. The compression release would get stuck in run mode often, but I learned to tap it smartly with a hammer where the camshaft bearings were on the pto side - worked every time. Sipped gas, burned clean, and I ran it hard on a pressure washer.

I would think you’d want the 212 CC motor? It’s probably a closer power match. If you go with the 3hp and it’s under-powered however, you can use a smaller pulley and carry on - it would be a touch lighter - however I think either will be less weight than the old Briggs.

 

[oil pan 4]

I had a smaller predator engine, one of the few I’ve heard of with problems. The compression release would get stuck in run mode often, but I learned to tap it smartly with a hammer where the camshaft bearings were on the pto side - worked every time. Sipped gas, burned clean, and I ran it hard on a pressure washer.

I would think you’d want the 212 CC motor? It’s probably a closer power match. If you go with the 3hp and it’s under-powered however, you can use a smaller pulley and carry on - it would be a touch lighter - however I think either will be less weight than the old Briggs.

Oh I already have a really big Honda gx200 powered compressor with aluminum and cast iron compressor it's got about 4 foot long tanks it weighs nearly 140lb. This is just going to be my small and easy to move tiny compressor. This little one has smaller nearly 3 foot long tanks, it's going to be light. I'm going for under 80lb, I'm not even going to put a belt guard on it.
This is for when I just need to fill a tractor tire, or car tire, blow dust around, blow down a hot water heater, sand blast something tiny like a crack for a few seconds so I can get the dirt out of it and weld it, run a half inch impact for one tire. Or God forbid a roofing nailer.

 

[oil pan 4]

I was about to put the engine on the tanks last night and maybe fire it up. Figured I better magnaflux around the bolt slots. Sure enough there are several cracks I couldn't see.
My magnaflux powder is just grinder dust that I swept up from around the bench grinder.

 

[oil pan 4]

I welded up 4 cracks with my gtaw rig.
I fired it up and ran up a half hour on it so far. With a 2.5 inch pulley it builds air pretty slow I'm going to see if tractor supply has a 3 inch pulley.
I had that 2.5 inch 5/8 keyed bore pulley in my junk collection and figured I would try that first.
It works as intended so far.

 

[oil pan 4]

Real easy to start, starts first pull every time like a Honda engine, sips fuel. Not even filling the fuel thimble all the way up, about 3/4 full gives an hour of run time.

 

[oil pan 4]

Ran the little 79cc air compressor for all it was worth yesterday to obtain a maximum oil temperature.
Full tank of gas, ran till it was out of gas, 90f outside, maintained 70 to 110psi in the compressor tank, never let the unloader trip.
The oil temperature when it ran out of gas was 210f.
So use your favorite flavor of oil that ends in 30.

 

[#18FAN]

Ran the little 79cc air compressor for all it was worth yesterday to obtain a maximum oil temperature.
Full tank of gas, ran till it was out of gas, 90f outside, maintained 70 to 110psi in the compressor tank, never let the unloader trip.
The oil temperature when it ran out of gas was 210f.
So use your favorite flavor of oil that ends in 30.

A 79cc engine can’t be running a big pump at all.

 

[oil pan 4]

A 79cc engine can’t be running a big pump at all.

Yeah that's the point.

 

[oil pan 4]

Well the mini compressor has been in service for a year and I've barely used my big gx190 powered compressor.
My little 79cc has been my go to machine.
I'm thinking take my Honda engine off there, stick a predator 212cc on there and sell it.