Weed eater engine conversion

[muddin redneck]

john
if you use a shorter shaft have you considered the different (steeper) angle it would give the engine. you may have to worry about the oil in the crankcase if you go to a shorter shaft. just something to consider. have you done any speed tests with the engines?

[pistnbroke]

I have the chain driven lifan so the motor is at the same angle as the shaft ...tip it down as far as your mounting permits ..about 15 deg .then top up at the highest filler hole ...no problems so far ....( has 60in shaft)

I dont see what you would need to import other than the coupling casting from motor to shaft ...the motors are cheap enough on ebay

[rbinhood]

John:

Does the air freight cost that you refer to apply to an entire motor + shaft set up, or just the parts for the conversion? Thanks.

[John O`Neal]

The shipping costs refer to the longtail kit less engine. It does not include packaging costs at the point of origin.

[rbinhood]

John:

Have you looked into whether there may be a cheaper shipping alternative? Not sure of the weight of the parts, but that seems a bit high for only the conversion kit. Thanks.

[JOBBER]

This is J. O'Neal's photo. I questioned Paraprop about this and he felt it didn't change shipping much. What if only the parts highlited by the green rectangle were shipped. Less the motor of course. Also included would be the: throttle cable, prop, shaft bearings, and misc. hardware. If the drive shaft, shaft cover tube, steering handle, and skeg were not included the package would seem pretty small. Instructions could be included for obtaining and/or fabricating the non-shipped parts locally. The packaging and shipping costs would have to decrease? Maybe others could shed some thoughts?

[rbinhood]

I have to believe that shipping on the items pictured would be reasonable, say $20-$30. I think costs go up quickly when you have long or heavy objects. The shafts and tubes could easily be obtained in the States.

[goose_716]

I ordered a 1 inch shaft with a .125 wall from discount steel believing that would give me a 3/4 or .750 inside diameter. Well I was wrong the 3/4 inch seal and bearing will not go into the shaft any suggestions. I believe i can spin the bearings on sand paper and make fit but the seal not sure what to do.

[hoytedow]

If you want a wall thickness of 0.125" and internal dims of 0.750", o/s dims must be 1.250".

[pistnbroke]

why do youi need a 3/4 shaft ? Is it 200 HP ? I have 8 mm ( 3/8)on my 6.5 hp geared down 2:1 and its fine ( 3 bearings ) ..why not use 1/2 in with 3/4 at the engine end if you need it to match the engine ???

My engineering alway fits where it touches .....ha ha

[goose_716]

If you want a wall thickness of 0.125" and internal dims of 0.750", o/s dims must be 1.250".

I can honestly say i don't understand that if the outside dimensions is 1.250 and the wall thickness is .125 seems to me the inside diameter would be one inch not 3/4 inch Where is my math going on this?

Pistonbroke when i say shaft i mean the outside pipe and the drive shaft is only 3/8 of an inch the seals that i have are 3/8 id and 3/4 od same with the bearings

[hoytedow]

Originally Posted by goose_716

If you want a wall thickness of 0.125" and internal dims of 0.750", o/s dims must be 1.250".

I can honestly say i don't understand that if the outside dimensions is 1.250 and the wall thickness is .125 seems to me the inside diameter would be one inch not 3/4 inch Where is my math going on this?

Pistonbroke when i say shaft i mean the outside pipe and the drive shaft is only 3/8 of an inch the seals that i have are 3/8 id and 3/4 od same with the bearings

Get a piece of graph paper. Make a drawing to scale and then measure it with a ruler.

[goose_716]

Sorry another question with the 52 cc motor. I see the much larger clutch plate and such on this as opposed to the 31 cc motor. From the plans that i received you had to take the 3/8 inch drive shaft and squre it off to 1/4 inch to work on the 31 cc motor. To be honest i thought it was inserted into a square tubing or something off the motr that was 1/4 inch but as i look at the 52 cc motor i don't see anything that the drive shaft inserts into do you just put it as close to the center as you can in between the clutch plates I wouyld think the large spring would be in the way. Please help.

[muddin redneck]

goose
i have been working on a mud motor too. my steel for the project was ordered from discount steel. due to imperfections in steel production not all tube are created equal. the bearings and seal you have are made with very precise equipment the steel tube you bought was not. you are lucky though that the bearings didnt go in the tube this way you can still have it machined to fit your bearings seals. that is what i had to do. after talking to the machinist that did the work he said that it would not be possible to buy tubing and be able to buy bearings that would just fit perfectly. hope this helps.

[goose_716]

This is the first that i have noticed anyone comment about this vary size in the aluminium shaft