O.s. 21tm

[Scrogg]

I'll be waiting, I Hope breakin goes as easy for you. Mine is still running warm but does not give me any trouble. It freed up a few more RPMs as well last night. It is getting faster.
One more thing, you'll have to dremel away a bit of plastic on that roto backplate. The header will hit, it is a tight fit.

 

[Greyhound]

I put the engine in 3 days ago and help my kid break in the mill. I didn't do anything with other parts except to cut the plastic on the roto backplate. thanks for the info, it was useful, when you install and know what to expect is really handy.

now my kid is just pop the front wheel for all the time. Nothing breaks yet.

I'll try to get the pic on later.

 

[Scrogg]

Sweet! I had a failure earlier this week.. The OWB locked down on the starter shaft and chewed up the shaft beyond repair. The OWB had already seen 3 gallons of use on my old 3.3, it never slipped though. It just pooped on me no warning.

 

[Greyhound]

What OWB?

 

[Greyhound]

Here are the pics. Sorry for poor work on the body. It's Proline desert rat. I drilled 2 holes, one to pull open the lid and the other for filler nozzle to insert.

 

[Scrogg]

Cut a hole in all three windows for engine cooling. Make them about 1.5" diameter. I usually trim my cooling holes to match the shape of the window it's in. The Desert Rat is a great body, I have one. I ran it forever, I can't even crack the thing.
Nice Revo!

 

[Greyhound]

Thanks for the tips scrogg!

 

[Scrogg]

Well the brand new starter shaft and brand new OWB locked down in about one hour of running. anybody else run into these kind of issues?
I am about ready to put a new 3.3 back in it. Can't win races with a engine you can't start!
I compared the starter shaft diameters between the Traxxas and the O.S. There is a slight difference. I guess this is why I am having bearing failures. I am going to call O.S. and find out for sure.

 

[Captain Chaos]

Not sure because I run the starter box.I was hoping you tested the gear change I was wondering how it worked out.

 

[Scrogg]

Nah man, I can't run it like this. The backplate bushing is worn and allowing the starter shaft to flop around.
LHS has a new 3.3 coming for me. O.S. will be getting this engine back.
I have read on other forums of people having this issue with the 18TM so it is nothing new, they better honor their warranty!

 

[MrClean]

Nah man, I can't run it like this. The backplate bushing is worn and allowing the starter shaft to flop around.
LHS has a new 3.3 coming for me. O.S. will be getting this engine back.
I have read on other forums of people having this issue with the 18TM so it is nothing new, they better honor their warranty!

Damn, sorry to hear about the trouble with that engine, I know you were liking it at first. I'm certainly no expert and only have experience with the 3.3 and the .26SS on the LST but I really like the 3.3. I was having trouble tuning it at first, of course it was my first nitro but now unless I change something to affect the tune it seems to hold it really well. I think the switch to O'Donnels helped a bunch to. Hope they honor their warranty too!

 

[Greyhound]

Scrogg, wouldn't you consider the roto start? I had a gallon thru and no problem so far.

 

[Scrogg]

I am using a roto, mine made it to the one gallon mark no trouble as well. I have 1.5 gallons on it now. 2 starter shafts and 3 OWBs and one worn out engine backplate bushing. The OWBs never slipped or anything, they just exploded.

 

[Greyhound]

Scrogg! Should I be worried now?

 

[Scrogg]

Time will tell! I hope yours holds up!

 

[Scrogg]

I figured it out, it was my fault mostly....I have a Duratrax roto backplate for the 3.3 installed.THis roto backplate allows the OWB to slide back and forth on the starter shaft a good 1/4" or more. The bearing was sliding back into the roto backplate and wobbling due to the roto gears being a free floating design.
One extra shim in front of the OWB and a piece of fuel tubing inbetween the roto backplate and the OWB fixed the slop issue. I placed a 1" piece of fuel tubing lengthwise into the roto backplate. I'd show a pic but a new computer and camera software MIA are preventing this.
So if you run a roto backplate, check for slop!
I also dropped to a 15T CB, the engine now hauls butt at 220F and did not kill the OWB.

 

[rckid91]

great to hear man

 

[Greyhound]

What is OWB stand for?

 

[rckid91]

owb= one way bearing