Glow engine

[minh-thanh]

The same plan with me

 

[minh-thanh]

some modify : ( maybe good or not, i don't know...just thinking and doing, If wrong, I will add experience for myself )

 

[minh-thanh]

Hi all !
I have two questions:
- Can i use 4-stroke engine fuel regulator for it ?
- Fuel: How much nitro ?
Thanks.

 

[Keith whiddett]

You will need two stoke model engine fuel which is methanol and oil!!! 75%methnol 25 %castor oil it will run on this but 5 % nitro will help it run better. And a good 2volt battery for the glow plug. Good luck. lol forward to the video of it running

 

[minh-thanh]

Thanks Keith whiddett !

 

[Keith whiddett]

Meant to add you can use the same carberretta for two or four stroke

 

[minh-thanh]

I test run it, it's not running, i will unfix it and check it again, i'm wrong somewhere...

 

[kadora]

Try to inject /syringe with needle/ small amount of fuel straight into cylinder trough exhaust port.
This overflow sometime helps to start engine.

 

[ixb1]

Hi guys, its pleasant to see that my boy have more brothers around the globe.

 

[minh-thanh]

Try to inject /syringe with needle/ small amount of fuel straight into cylinder trough exhaust port.
This overflow sometime helps to start engine.

Thanks kadora !
It 's not run .

 

[ixb1]

Not runnig?!
If you remove plug and turn shaft,move its freely?
If you put plug into head and flip prop counter clockwise,did you feel resistance by compressed air and hear popping sound?
Filament in glow plug glowing if connected to baterry?

 

[minh-thanh]

Hi ixb1 !
remove plug and turn shaft,move its freely : yes
put plug into head and flip prop counter clockwise,did you feel resistance by compressed air and hear popping sound : yes
Filament in glow plug glowing if connected to baterry : yes
I think i make the clearance between the crankshaft and the font bearing to much

 

[ixb1]

If you put about 1/2 ml of fuel into intake valve and flip prop few times,fuel will drain from front bearing?

 

[minh-thanh]

Yes ! fuel drain from front bearing.

 

[ixb1]

How big is shaft clearance in bearing?

 

[minh-thanh]

ixb1 !
shaft clearance in bearing : 0.3 mm .

 

[ixb1]

Hmm this is too much.

 

[Mechanicboy]

Clearance of crankshaft is too much.. you need this book, see chapter two about fits and tolerances in page number 17 (part A).
The tolerance in crankshaft/bearing in front house must be very little clearance and running without friction when the engine is new. Use the adjustable reamer to adjust the diameter in the bearing and try each time until the crankshaft goes into bearing without slack.

Download this book part A and B, print out and create a book, worth to have in your workshop.
https://rclibrary.co.uk/files_titles/1996/Engine_Encyclopedia_RonMoulton_partA.pdf
https://rclibrary.co.uk/files_titles/1996/Engine_Encyclopedia_RonMoulton_partB.pdf

Picture of the set of adjustable reamer..

 

[Mechanicboy]

Front house bearing - 10 mm H7 = +0,000 - +0,015 = 10,000 mm - 10,015 mm
Crank shaft - 10 mm g6 = -0,005 - -0,014 = 9,995 mm - 9,986 mm

I prefer to make crankshaft first 10,000 mm when the shaft is polished with fine emery paper #500-800 or lapping ring + lapping paste for shaft if you want (+ or - not so very important in tolerance since the lathe is never 100% precision). Measure 10 mm diameter must be same in whole length of crank shaft, use emery paper if one of the part of crank shaft is too thick (must be parallel in length). Then drill the bearing house with 9,8 mm drill and use reamer to adjust the diameter, then ream into the bearing house and try each time with crank shaft until the crank shaft fit into the bearing without slack and rotate free with oil applied on..

 

[minh-thanh]

Hmm this is too much.