Which collet for my OS 21RG-M

[dannyual767]

I know the threads are 1/4-28 and I've got a collet for it but I can't tighten it down. The engine's flywheel has a recess and the collet's hex goes inside the recess so I can't get a wrench on it. Which collet should I be using? Brand and part #? It has to have enough hex to stick out of the recess so I can get a wrench on it.

Danny

 

[waltr]

This Prather collet from tower should work fine.

http://www2.towerhobbies.com/cgi-bin/wti00...=LXDP84&P=7

They're both 1/4"x28 and you'll be using a 3/16" cable.

Good luck,

Walt

 

[dannyual767]

This Prather collet from tower should work fine.

http://www2.towerhobbies.com/cgi-bin/wti00...=LXDP84&P=7

They're both 1/4"x28 and you'll be using a 3/16" cable.

Good luck,

Walt

Walt, that may work. I'm a little concerned with the size of the hex at the engine end of that collet. I don't know if it would fit inside my OS engine flywheel recess or not :unsure: .

 

[dannyual767]

Here is a picture of the engine and you can see the indention in the front of the flywheel:

http://www2.towerhobbies.com/cgi-bin/wti00...=LXALL8&P=0

Is anyone running this engine and if so, what collet are you using? Thanks.

Danny

 

[dannyual767]

Anyone :unsure: ?

 

[Lar'Dog]

B) Danny,what boat are You putting that engine in? :blink: Later

 

[waltr]

Here is a picture of the engine and you can see the indention in the front of the flywheel:

http://www2.towerhobbies.com/cgi-bin/wti00...=LXALL8&P=0

Is anyone running this engine and if so, what collet are you using? Thanks.

Danny

Oh,

I didn't know about the opening on the flywheel.That is a little different.

If you can measure the size of the hole and the depth,

I can double check a few different collets when I get home from work.

 

[dannyual767]

Lary, its going in my old Dumas DV20 that I started building in 1990. I recently gutted the thing and sanded all of the paint off of it. I've torn out bulkheads on the inside and I've removed the submerged drive system. I have a used Speedmaster stinger for it now and the OS engine is brand new from Towerhobbies.

Walt, I'll try to get those measurements for you.

 

[Krusty 181]

Hello Danny , i was using a OS RZM for a little while which has a similar flywheel so i know the problem your talking about , i ended up with an collet that was the right thread , but ended up making an alloy spacer ( like a thick washer ) to space the collet out enough to get a spanner onto it , it worked fine , it never came loose there was plenty of thread for the collet to bite onto , it was a simple fix as i could not find a collet that would suit either

hope it helps

Andrew

 

[Ben Daigle]

I used an aeromarine collet #1732 @ www.aeromarinerc.com with no mods.

 

[dannyual767]

Guys, in this picture you can see my blue head OS21RG-M engine and my OPS 67. You'll notice the indention in the OS flywheel. The indention goes in a solid 3/8". You can see the collet for it on the ground. If I were to add enough spacers to bring the collet out enough to get a wrench on it, the collet wouldn't grab onto enough of the crankshaft threads :angry: . You can see that the crank threads don't even protrude past the indention of the flywheel !

What I need is a collet like the one on my OPS! I bought this collet when I bought my OPS 65 way back in 1979! Does anyone know what brand it is???? It has plenty of hex length that would stick out of the flywheel of the OS engine. If only it were threaded 1/4-28!

Anyone have any idea who makes the collet that is on my OPS engine in the picture?

 

[dannyual767]

I used an aeromarine collet #1732 @ www.aeromarinerc.com with no mods.

Ben, would you happen to have a picture of this collet? I need to make an order with AM anyway but I want to make 100% sure that what I buy will work with this OS engine. Thanks!

 

[sport hydro]

I have an OS21RZ-M and I use the Octura 1/4-28. It has a thicker hex head on the end. I have no trouble with fitting a wrench on it.

 

[dannyual767]

I have an OS21RZ-M and I use the Octura 1/4-28. It has a thicker hex head on the end. I have no trouble with fitting a wrench on it.

Sport, does your Octura collet look anything like the collet on my OPS 67 in the picture? If that collet had the correct 1/4-28 threads, it would work on my 21RG-M. Does your RZ-M have an indention in the flywheel? Mine is indented 3/8" so I lose that much of the hex on the collet. You can see that the my collet on the ground by the OS engine would never work . Do you have a picture of your Octura collet?

 

[Saugling]

I use the RZ flywheel, but it is modified, the front looks like your OPS flywheel.

 

[dannyual767]

I use the RZ flywheel, but it is modified, the front looks like your OPS flywheel.

Did you modify it because you couldn't find a collet that would work?

 

[gil sonsino]

If I'm not wrong it is an old NORCO(out of business for long time) collet that I used to use on my Picco's and OPs's.

Gill

 

[dannyual767]

If I'm not wrong it is an old NORCO(out of business for long time) collet that I used to use on my Picco's and OPs's.

Gill

Thanks for the info, Gil. It doesn't look like I'll be able to buy one like it then .

 

[troytron1]

If you can find someone with a lathe, have them turn the lip off back to the solid part.

 

[sport hydro]

I have an OS21RZ-M and I use the Octura 1/4-28. It has a thicker hex head on the end. I have no trouble with fitting a wrench on it.

Sport, does your Octura collet look anything like the collet on my OPS 67 in the picture? If that collet had the correct 1/4-28 threads, it would work on my 21RG-M. Does your RZ-M have an indention in the flywheel? Mine is indented 3/8" so I lose that much of the hex on the collet. You can see that the my collet on the ground by the OS engine would never work . Do you have a picture of your Octura collet?

My flywheel is the same as your RG-M. The hex area on the Octura is about the same 3/8" that the inset is. This still allows me to get a wrench on it. I'll try and get a picture of it.

On a side note, can anybody tell me where I can get a replacement crank for my 21RZ-M? OS discontinued them.