Yesterday a mate brought his old 2 speed (now a push mower) GXV160 over because it wouldn't start. Ok no spark I didn't have a spare Honda coil, so I looked at using a Chonda coil. Just had to run a 6mm tap through the post that was in the Honda casting, easy fix, put the Chonda coil on and still no spark. Pulled out another Chonda, and gave it a spin and good spark. Put that coil on the Honda and still no spark. Ok must be a problem with the flywheel so swapped it for another one off a GXV160 in the scrap pile. No change still no spark. Ended up putting the rusty old cast iron flywheel from the Chonda on it and it ran like a treat. I hate it when I get something running and I don't understand why, it doesn't make any sense. The magnets in the Honda flywheels feel fine so I have no idea.
If it was me I would think none of the things that I changed actually related to the problem at hand and it was just the jiggling around that resolved the problem. Probably not the case here but I’ve had that scenario before.
Perhaps it has something to do with the chonda flywheel magnet count or position. What happens if you put the flywheel back on the scrap Honda motor? Do you get a spark off that?
Hi ironbark, I had riggeled and jiggeled for several hours before I resolved it. Can't do anything with the Honda wheels as they have been stripped and are in the ally scrap bin
Hi AVB, yes that makes sense, but they were installed the correct way. Just annoys me when I don't understand something like this. Anyway my mate rang last night and he said that it is now starting easier than it has for a while, so what ever failed was failing slowly for a while. He loves his Honda again but he still can't get his head around the rusty old Chonda flywheel that is underneath the covers
No it about which pole is leading the other. It been very long time since I had the papers on this [kinda wish I had scanned them] but old cast iron points engine had to magnets polarity reversed in order to work with the new magnetron coils. Basically they old points system was a positive ground system and new system uses negative ground system [ie NPN transistors don't work with positive grounds.].
A good example of this is a horseshoe magnet. if you flip it the polarity on the left changes to what previously of the right and vice versa.
Hi rollo, the couple of Chondas I was testing both have the same kill switch as the Honda. Not that it is relevant because anytime I am testing this stuff the first thing you do is remove the kill switch wire, but thanks for the thought.
I have now come up with something I haven't come across before, probably because I haven't tried it before. I went to fit a Honda GXV160 motor on an Ariens self propelled and the bolt holes don't match the Briggs bolt pattern. All the Chondas match the Briggs but these don't. It isn't a big deal , I can drill new holes but I was so surprised. Anybody come across this before
Came up with a strange thing on a Honda motor over the last few days. I went to bolt a GXV120 onto a Victa body but I think I must have taken one of the mounting bolts from this motor to bolt the GXV160 motor onto the Ariens a week or so ago. No problems I thought just grab an 8mm bolt. Tried a couple, no go, looked at the thread and thought it must be 8x1.00mm but no. I went back to it a couple of times over few days thinking what am I not seeing here. Last night I pulled out the thread gauges and couldn't believe what the thread is 5/16x24TPI. Why would Honda have done this, just bizare.
I’m thinking it’s probably a carry-over from the original?
I know in the 50’s a lot of Japanese engineering was a direct copy of something from either the US or Europe. There were parts of Toyotas that would directly bolt into Chevrolets and vice versa. Some bits of Toyota Crown you could use Chevy Nova bits for and it wasn’t a close match, it was exact.
To save on the costs of updates to tooling and processing many things don’t get changed, if it works they leave it be. There are huge economies of scale in production so the manufacturer might make vast quantities of things and continue with a bit of plant for as long as they can get away with it.
I know with one of my original 1970’s Toyotas, that’s now long gone, some of the same minor parts fit to a 2015 model. The cap off the power steering reservoir and the mounting clips for some engine ancillaries are identical.
Hi Ironbark, Makes sense but still strange seeing imperial threads on a Japanese engine. I won't be chasing up one bolt, one hole will get drilled out and a bolt and nyloc fitted
Maybe back when the 120 came out (about 1983) they supplied them bare and buyers (eg jetfast, superswift) tapped the holes as they saw fit. No point tapping the 8 or so holes under there at the factory if only 3 or 4 are used
Last time I looked there are quite a few mounting holes under honda motors
I think Tyler is on to it , as well as complete mowers imported, Honda motors and parts are imported, so some Honda models can be assembled in Australia, still to this day, below are some that are assembled here now .
Everyone knows that a 5/16 UNF thread is no good for alloy but this doesn't stop people using a fine thread in alloy.
Makes sense that the engines were imported then drilled and tapped here.
The reason the Honda and Chonda coils don't interchange is because the Honda has a E core coil with a 2 pole magnet (N S)on the flywheel to reverse the magnetic flow though the coil and the Chonda had a C core coil that uses 3 magnets (N S N) on the flywheel to reverse the magnetic flow through the coil.
Well there you go Max, that is good to know, but what is also good to know is that you can use a Chonda fanwheel and coil on a GXV160 motor, that I know, but you have to pick your Chondas because not all the Chonda coils are the same