OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions on Other Engines Replica Honda engines, Scott Bonner & Pope.

Hello, The two engines pictured look much the same.
I haven't had these engines before and plan to make one out of these two.

The donor engine (off a Scott Bonner) has carb missing & more.
It will give up its starter and starter cup & magneto.

I think I have read in some threads here that parts are inter changeable.

Hi mark electric, the pope spitfire 40 chonda is similar to the honda gxv140 and I don't see any reason you couldn't make a good engine out of the two . The pope chonda is a surprisingly quiet and smooth engine as is the honda gxv140.

The key difference between most Chondas is the way the starter/blower housing mount up to the block. Some have 3 studs on the block (like the Scotty) the the starter bolts up to. Others, like their Honda counterparts, mount up around the perimeter of the block using M6 bolts.
It depends if the 2 are the same, in that regard, otherwise you could find yourself turning the spitfire into the donor engine and mounting the Scotty to the Pope.
Keep us posted on your progress.

Thanks Roebuck, bigted
I will strip and clean them up. Both engine turn over nicely.
Will take a few pic's and let you know how I go.

This is obvious Mark: remember, the chondas are made in the same three types as the Hondas: GXV120, GXV140, and GXV160. Quite a lot of parts are different between those three engine sizes. As Rob and Theo said, provided both of your chondas are GXV140 clones, your only problem will be checking whether the manufacturer deviated from the Honda design in some minor way, right where it will be least convenient. I suggest you check that the parts will bolt together before you get too far into the project. If the two engines are different sizes, there will be more subtle differences (different flywheels, different ignition modules, different ignition module mountings, spacers under ignition modules, etc.)

Rob and Theo both know way more about these differences than I do, so I'm sure you'll be able to get good information if any difficulties crop up.

I have put the pope starter and starter cup on a rover before, it was a direct fit, the starter cup has to remain with the relevant starter otherwise it all just bolted together.

Thanks MrMckay, I haven't done it myself, but that fits my preconceptions.

On what I've seen so far, the cylinder block and other core components on chondas are identical to Hondas, but the trim items (in particular, cowl, starter, air cleaner, governor plate and muffler) are quite different both from Honda, and from other brands of chonda. They mount the same way, so they are interchangeable as complete assemblies, but the parts of those peripheral components are not the same either as Honda, or as other brands of chonda.

The concept seems to be, everything is interchangeable except individual parts of peripheral, bolt-on bits. That way all of the core chonda parts can be sold as spares for Hondas, and if you have them, you can replace any of the parts of a chonda with genuine Honda parts. That is very convenient for chonda sellers, Honda owners, and chonda owners. It probably doesn't thrill the Honda dealers so much, however.

Thanks, this has been a bit a discovery, I enjoy seeing the differences in design.

This went surprisingly smoothly. It is all finished and is running nicely.
Noticed that it runs quiet, smoothly with very little vibration.
Had to swing across from the Scotty, starter and cup, magneto, metal flywheel shrouds ,governor plate and other bits and pieces.





I have a Victa V40 here that I am now stripping and am noticing it is different again.

Hi Mark Electric , The victa v40 engine ,you should find is similar to honda gxv120 engine. and is a good little mower as well. You have done a nice job on the pope/scotty too . Cheers

Cheers, I normally walk past these types of OHV mowers at the recycle centre, I might start getting them now. LOL
I've already stripped the V40 and have the carb soaking tonight. Will let you know how it goes.

Whenever I get a chonda I check the compression , it can save you a lot of headachs and give you a better idea of the life it might have left in it. Mostly come across dirty carbies in these .

Mark, if you had to fit the other chonda's ignition module, it sounds as if one of them was a different sized engine from the other.

Honda used two different ignition modules on the small vertical engines. This one was used on the GXV120:


This one was used on the GXV140:


Note the offset mounting holes on the GXV140 module, which Honda described as Capacitive Discharge. You can see that the GXV140 had mounting holes for both modules:


The GXV120 module (called N type) used yellow and red holes, the GXV140 module (the CDI one, called A type) used yellow and green. I haven't heard of an N type module being fitted to a GXV140 engine. You have to put spacers under the CDI module, to bring it to the correct height to match the flywheel - it has a thinner laminated core.

The GXV160 cylinder casting also has the bosses for all three holes, and may be fitted with either N type or A type module. It requires 3.2 mm spacers for N type, and 6.2 mm spacers for A type modules.
Flywheels have different heights to suit the spacers: no spacers for GXV120, short spacers for GXV140 with A type, short spacers for GXV160 with N type, and tall spacers for GXV160 with A type.

Note that The GXV120 only has two mounting pads for the module on the cylinder casting, and only the N type module can be fitted.

I think you'll find that chondas use exactly the same system as Honda for all that.

Hello Grumpy, I am doing a run of OHV engines and do have 2 x GXV140's to do.
So that information is great.
I haven't touched a GXV120 as yet.

I swapped the magneto on the Chonda because the lead was broken on the Pope engine.
If I repair the lead it will more than likely be serviceable.

Please see images of Victa V40 engine.
This one has the disc breather, the previous 2 engines had what I call a reed valve type breather.

Images of Chonda Magneto's.

Both those modules are N type, fitted to all GXV120s, some GXV160s, and no GXV140s. In other words, it all fits Rob's experience that the two chondas you've reported would both be GXV120 clones. I'd repair the broken plug lead and put the module into the junk box as a spare, but the repair takes time and effort, which may not be worthwhile. The engine you've just shown with the white plastic disc PCV valve (Honda uses a brown impregnated-fibre disk valve, fully interchangeable with the white plastic one) is also a GXV120 clone.

I don't understand what you referred to as a reed type breather valve. I haven't yet heard of a chonda that doesn't exactly copy Honda's disc valve, except they use that white plastic disc instead of the brown fibre one. Can you show us some pictures please?

I fixed the lead today seeing it was in my hand.

With reference to the reed valve type breathers, I used to work in refrigeration for quite a while and in the compressors they used reed valves, which I are a piece of thin spring steel.
They are pictured above in post #58348.
I will take a close up tomorrow.

This V40 engine wasn't turning over nicely, it wasn't seized but had some resistance, so I pulled it all down to find presence of water. Not major, intake valve shaft small signs of rust. Piston and rings were choked with brown rusty liquid.

Engine was low on oil, thought the bottom seal was leaking, turned out the sump plug had a slow leak.

I'm glad you posted that, Mark - I see it has not only a plastic camshaft, but a very simple decompressor mechanism that may or may not stand up in the long term. That whole assembly is copied from the GXV140 instead of the GXV120 which the remainder of those engines is cloned from. I'm disappointed - the GXV120 is my favourite small mower engine, and I had been thinking I might one day acquire a chonda of 120 cc for my own use. That idea is now off the table, unless I fitted a GXV120 or GXV160 Honda camshaft (all cast iron, with a decompressor of considerable elegance as well as excellence).

You will need to look closely at the piston rings, to see if they are significantly rusty. The crankshaft is cast iron, and does not rust easily, and the aluminium connecting rod doesn't rust at all. Note in the bottom of your last picture you see the large oil return passage, which shows Briggs how it should be done.

Reed valves are used in some of the better 2 stroke engines, but I'm cautious of the idea of using them as PCV valves. However I want to see their design before I express any negative views.

Hello, the rings seamed serviceable to me.
Top ring was chromed and marked "s"
Second ring was marked "T"
Oil rings were the rail type.
I have fitted them with the markings facing up.

An example of the ring end gap, second ring 0.008".

Valves lapped and clearances set as per GXV120 Specs. 0.006" IN and 0.008" EX
Piston fitted with arrow facing the push rods.
Timing marks on the gears clear to see.



Below is the breather type on the Pope and Scott Bonner engines.
If these types of valves leak I have flipped them over in the past.

Thanks for that Mark. I've had a close look at a couple of sets of very worn chonda rings in the past (courtesy of Rob) and I believe they were of good quality and had lasted a very long time in service. They seem visually identical (except for markings) to late-model original Honda rings. If you only have an 0.008" gap in the second ring (the fastest wearing one, and the only un-chromed one), I don't think that engine has been used beyond a bare running-in period at most. That is close to the minimum gap specification for a factory-new engine.

A few months ago we had a member (charmaine) reporting symptoms which sounded very like the results of a solidly stuck-closed PCV valve on a chonda, and I couldn't understand how it could happen with the Honda disk valve. Now I think I can see what happened - that cheap flapper looks as if it were specially designed to stick, and the vent-hole below it looks to be a fraction the size of the Honda one, so it may block as well, especially if the so-called valve is stuck closed some of the time.



(Picture cropped from one of yours, above, with red circle added around PCV port).
Like the plastic camshaft and simplified decompressor from the GXV140 that we are seeing on your GXV120 clones, it seems at least some chondas are not true copies of Hondas. So far it seems the Pope and Scott Bonnar chondas are on my don't bother list. I've seen some of the details of a number of Sanli GXV120 chondas, which seemed to be quite accurate Honda copies - but I don't recall seeing the camshaft.

To be fair to the GXV140's plastic camshaft and clockwork-style decompressor, they seem to work properly on the GXV140s as far as I know. However the GXV140 was a sort of interim, ultra-lightweight engine made in the US-only, and it went out of production in 2003. The GXV120 is still in production now, after 31 years so far.

Finished assembly today, It was hard to start & when it did it wasn't running very well at all. Of course I thought the worst & that I had assembled something wrong. Pictured below on the left is the plug it came with. So I tried the one right and it started better and ran better, but was surging up and down.


Not wanting to remove the carby again for cleaning, I cleaned up and tried a bunch of plugs.

It ran the same with each one.
So I bit the bullet and pulled it all apart again to clean the carb again.
What I did was remember to clean the emulsifier tube a lot better.
This time using my jet drills, feeling my way, I worked a slightly larger size drill through all the holes, using the back of the drill, I also I guess force a larger size through the jet as well.
Once all put back together, it now runs as it should.

A few pic's.