Weed eater engine conversion

[ben2go]

con

I think

[Paraprop]

OK. Below I have put together some key data:

The long tail shafts are made for the HONDA GX engine series.
There are 2 basic versions. They are related to flange and PTO shaft size.

Small version is made for GX120, 160 and 200 and their clones of course
Large version is made for GX240, 270, 340, 390 and their clones.

Both versions do exist WITH and without reduction (direct drive as seen on earlier pictures posted)

For Small version reductions available are 2:1, 2.5:1, 3.2:1
For Large version reductions available are 2,5:1, 3.2:1, 3.6:1

Propellers are available from 5” till 11” diameter in 0.5” increments and from 11” to 17” in 1" increments. No Pitch given.


Example:
A standard GX200 out of the box will use a prop in the 6.5” to 7” range with the direct drive shaft. Whereas my marine version of the GX200 will use a 7” to 7.5” depending on the boat type and load on the same direct shaft.

However with reductions the props will go up to 11”, 12”, 13”and even 14" for the 3 respective reduction ratios.

The smaller GX120 engine weighs about 13 kg or 29 lbs whereas the GX200 is about 16 kg or 35 lbs.

Right now I am working out part costs and shipping.

Is there interest for the Large version too or can I focus on Small version with related reductions and props ?

Thanks
Dan

[Paraprop]

The shaft housing consists of a 1 1/2" external Diameter pipe which was galvanized.

The shaft itself is made from an 18mm steel rod. This steel rod is taperred on the propeller end and a key fitted. This is where the propeller will be mounted. finally a brass nut and a washer is locking the propeller on the taper.

On the coupling end a 22mm adapter with a flat is threaded on it. this flat will interlock with it's female counterpart located in the aluminum coupling housing.

From end to end, I measured the entire shaft to be 93" long.

[muddin redneck]

do you have any pics of the inside of the coupler? does it have any bearings or bushing in it? what is the brand of the long tail kit assembly?

[Paraprop]

Here it comes...

The coupler is an Aluminum casting with 2 bearings inside.
At the engine end there is an adapter which is bolted onto the engine PTO shaft with a Key. The other end of the adapter mates to the coupler shaft.

On the Long Tail shaft side of the coupler, there is the matching female end to receive the flat of the long tail shaft end.

All the elements shown on the picture including bolts and keyway are all that is needed to mount the coupler onto the engine in a few minutes.

A 3 kg carton box can take this Small version coupler unit + max about 3 propellers (6.5")

[Paraprop]

Most was already said for the Props.
below a few pics.

first one top and side is the 6.5"

second one is an 8"

Propellers are available from 5” till 11” diameter in 0.5” increments and from 11” to 17” in 1" increments. No Pitch given.

[Paraprop]

Below picture shows the cast aluminum throttle lever which fits onto a pipe and the chromed throttle plate which is a direct substitute to the Honda governor/throttle plate normally supplied with the Honda and clone engines.
Throttle cable can also be provided.

[Paraprop]

The Last 2 elements

The engine Plate with swivel mount, complete with engine fixing bolts.

The handle bar where the throttle lever will be mounted. The throttle cable goes into the tube through the second orifice seen and comes out at the end of the tube to connect to the engine throttle plate.

[Kingfisher]

This thread is six and one half years old and has over 700 post. It is by far the longest thread that I have ever read. Paraprop has brought something to the table that this group is going to eat up. If not the complete unit, then the pieces. There are some people in this thread that are very talented and have nearly reinvented the wheel producing their own version of the longtail. It may not have been as much fun but having the parts that Paraprop is showing us, available to order and use, would have put them on the water a lot faster. Just having a selection of props to choose from would have been and still would be a good thing.
Paraprop if you can fill orders for parts or complete units at a fair price you may do very well with this group and others that want a longtail type rig.

[Mark Wo]

Yes, I like everything I see as well but do have a couple of questions.

1. Parts - where do you get parts if the motor has some issues. After purchasing a Chinese made motor that broke, finding the correct parts to make the thing work again has proven impossible.
2. Cast aluminum prop. If it is cast and you are running this much power to it, I'd be worried about it cracking. I don't think cast aluminum would work well using the motor the way hunters use a mud motor. The pic's look like hte motor is forged however, not cast.

I'd too would love to purchase one of these motors.

Mark

[hoytedow]

Well done, paraprop!

[rbinhood]

Where did you obtain the exploded diagram of the Ryobi electric start weed trimmer contained in one of your earleir posts? I recently obtained one of these power heads and am in the process of doing a longtail conversion. I am running the prop through the standard gearbox that is at the end of the trimmer head. I would like to get all exploded views for this model, including attachments, if possible. Any suggestions appreciated.

Thanks.

[Paraprop]

1. engine after sales:
My wife is an official Honda dealer. We do carry all the spare parts for our engine. We do even tune those engines for racing applications.
By the way if you use Chinese clones, you can use original Honda parts to replace the weak chinese parts.

2. Those props have proven themselves here in Thailand in the most difficult environment for several decades already. This technology is nothing new here. The only innovation is that we came up with a good aluminum cast design for the coupling unit. But even this unit is already proven for 4 to 5 years of heavy use by all trades on the sea, rivers, canals and lakes.

Here in Thailand, Laos, Cambodia and Burma, the people make their living with such small boats and use them everyday the whole year round. Honda has taken over the market because of reliability and availability of a good distr. network.

[GOOSE316]

Let me say this has been a learning process.

Ordered a motor, kill switch, fuel tank, and cover from monsterscooterparts.com.

On the first shipment I got the motor and kill switch. I then called back, and had to wait another week to get the tank. When I got the tank , the cover wasn't in it....so another week.

Issue 1. The fuel tank was exact and had to be shimmed out with 2 nylon spacers in order to fit the motor, not really a big deal, just another trip to truevalue.

Issue 2. The electric start worked great, however the way it was assembed left a little be to be deisred. The pull cord did not engage the electric start which made it useless. I had to dissasemble the electric start and not only grind off the 4 screw studs but I had to grind the circular spacer that attached the pull start to the electric start.

Issue 3, The carburators on these things take a not very standard throttle cable end... looks like a small cylander...not your standart elbow connector.

Issue 4, The fuel tank leaks like a banshee

The next issue or obstacle would be... and nothing of anyone's fault really is the Honda Clutch kit that OrphanedCowboy reccommends doesn't exactly fit. It needs shimmed out with 4 1/8 spacers in order for the clutch bolt heads not to rub the clutch housing...not a biggy but locked the motor up when I first started it.

Its all built and assembled minus the trigger/throttle handle i'm still waiting for on ebay...been longer than it should have been.

The motor did start right up, however, the cover for the carburator that reads CHOKE ON and OFF is backwards, when the choke is positioned on, its actually off... kinda funny.

I like the idea of a weed eater engine, but finding something that would be more readily available would be a better choice. In my opinion.

[GOOSE316]

Will also add, I took the muffler off and turned it upside down to point away from me...