Old Skool

It's called The Fix!

On another note, my NTC3 has developed an appetite for diff gears all of a sudden. Ran it last weekend with the Yokomo one-way front/solid axle rear on a large VHT-treated track. No problems. Returned for a day of testing/tuning today. First the front gear gave out. Replaced it. Then both the rear ring gear and the pinion stripped. Okay, replaced those as well...not too happy but it needed to be done. After the next tank and staying off the boards, the front gave out again.

Okay, now I'm pissed.

I ripped out the one-way and rear solid axle and stuck the stock diffs back in. For the record this car is going to be torn down to the last screw and rebuilt when my Fix parts arrive next week. I must have replaced the diff cases on both ends of the car at least twice ever since I bought it. When it's intact it's untouchable, but the fragility has to go.

fastharry™

iTrader: (4)

I would absolutely save those parts,and with a nice letter,send them back to associated.....and DON"T send them to customer service.....send them to Roger Hustings...orsend them to Cliff Lett....Or,in fact,Gary Owen..this way you KNOW the parts are getting to the top....

let them know EXACTLY what you've done,and the track surface your're running on....and a breif history of the car.....



I'd also shim the gears tighter when you rebuild it....

CHUCKMANDO

iTrader: (4)

I went to run yesterday locally, where mostly 1/8s go. Unpacked everything to notice I forgot my mrx3 . Oh well it was tc3 against 1/8's again. Good news is nothing got broken. Went up against 5 1/8s. All very expiranced and 1 was A main open driver. Of course, they had alot more top end, but the tc3 held its own. One of them was having problems in the beginning and I was able to stay ahead most of the time. Most of the time, I wouldn't get laped on a large pretty much sweeping track, with a couple of hairpins. Matter of fact, the A main driver watching me practice, complemented me on how well the car was hooded up. For all of us that didn't jump ship, we know the real deal. GO NTC3.

NOW, if it can only stop raining out here in the east. Next weekend, a big race and the extended forcast for Sat is rain again Harry, you still going?

fastharry™

iTrader: (4)

I'll be there...I'm hoping to go Sat.....and stay over at the local hotel...got to watch the weather.

bbntc3

WE'll theres a difference in a electric TC3 conversion shocktower and a NTC3, Theres not even a place to add the fix on a electric TC3 shocktower.
You think "THE FIX" will fix the gear stripping?? LOL LOL !!
Shimming the gears correctly and staying off the boards will do more for the diff gears than the fix.
Hmmm, I thought all you guys had no diff gear problems ? I thought I was all alone with this problem.

fastharry™

iTrader: (4)

bb,I agree with you.....I think the shimming will really help....I haven't had any[problems],but I did notice the differnce in play in the rear gears between my 2 cars.....


one thing I have noticed,is that the diffs do tend to loosen up..and that the gear lube gets thrown out of the diffball's AND off the ring gears......

one guy recomended a drop of 100,000 silicone fluid on the ring gears instead of the associated stealth lube..that may stay on better....

maybe the gears get dry and heat up...

bbntc3

I have been using dielectric grease by Dow Corning, it seems to conduct heat better and not melt down has fast. I think you are correct Harry the diff lube gets hot and runs out letting the ring gear get dry and over heat.
It's wild how diff people seem to have different gear problems. I never stripped a front diff gear with a solid or a oneway, but have about 3 sets of team cvds twisted up like pretzels out of the front.
My diff gear problems has always been in the rear, either the Richey power would rip the teeth off the diff or the center of the ring gear always melted down. The new gears and maybe the new greese I'm using has work out ok for me so far.. No gear problems at all so far this year.

fastharry™

iTrader: (4)

that guy who said there's different amounts of play with teh 2 sp shaft also had a good point....and that since he started shiiming,he;s had no problems....

OLD School's running ona VERY high traction surface...and thats also critical to gear heat...

but,on the other hand,the car is so easy to work on,if I have to pop the diffs to retighten and relube them before every race day,who cares....

it still takes WAY less time to do that then to put my HPI's back in tweak


and one thing we ALL agree on...when this car is running,it is the fastest car we've driven....


I also think that this problem would occur on any shaft drive car.with ball diffs.....the responce is so great,there's no play anywhere,and when you hit the boards on power,theres no slip to absorb instant shock..

alucard13

what do you guys mean by shimming the gears?

Shiloh

So far this year, the NTC3 is dominating at our local track as well. Yesterday for example, the NTC3 grabbed 1st, 2nd, 4th, and 5th in the A main at our local track. One serpent managed to squeak into 3rd place. The guy with the serpent was the only racer using a one way, and he was driving his butt off to even hold 3rd place. The first place NTC3 driver had a full lap over the serpent driver. The NTC3 is the real deal.

Shiloh

alucard13: You can shim the input shafts and the diffs to control how tight the bevel gear mesh is. You want there to be a little play, so the gears do not bind. But you do not want very much play, since that can lead to stripping the teeth from the bevel gears. I strongly recommend the white delrin bevel gears, since they are machined instead of molded. This lets you set the mesh much tighter with causing binding. The molded gears have sloppy tolerances, and it is more difficult to find a perfect gear mesh with those. With the molded gears, I would suggest shimming them so they actually bind and then run the car to break them in. The molded bevel gears wear easily enough, so you can actually wear some play back into them that way.

alucard13

at one of our tracks they are going to have a 2 hour endurance race at the end of june. right now i am running mostly stock stuff. any suggestions on what spur gears and pinions will last that long? if so can you post a link? I have the mugen mr12 engine so i should have enough stamina. i just gotta richen it out a little. also if anyone has done an endurance race what tips can you give me? Thanx for the help

also, what kind of reciever battery will hold up for two hours? 1100mah? also what kind should i put in the transmitter that will hold up for 2 hours? for a reciever batter what are the best? I have a JR XRS3i.

Old Skool

A-HA! My LHS is getting a shipment of the Delrin gears in this week, so I will be stocking up on a couple of sets of those and extra shims. Thanks for the clarification! For the record I've been alternating between an Ofna 7-port and my RTO. The 7-port has a lightened 3-shoe/HD spring setup while the Ritchey has the MIP clutch. The former is snappier and the latter is smoother but non-adjustable. Tires are Nitro Shoes foams, 45 front/40 rear, and I no longer have any swaybars. For a giggle I replaced one rear tweaked alumin bone with the composites, and I can detect no negative effect on the handling. During the rebuild I guess I'll do the other three too. My poor GH chassis is all scratched to hell now.

And it's a damn shame that I can't use the perfectly good spare Mugen centax clutch that's just sitting in my old decomissioned MTX-2...

fastharry™

iTrader: (4)

OS....make sure you catch all the hints that have been posted..

• spin the diif rings in the gears,make sure they are free
• make sure you lube the orange rulon washer
• make sure you compress the diff spring with pliers...(as per the instructions)
• USE the white gears
• shim them if needed..esp the rear set..
• make sure you lube the ring and pinion gears
• after you rebuild the diffs...RECHECK the tightness of them after a few tanks...(I guarenteee not everyone is doing this)
• Maintain the diffs....Even if they feel smooth,take em slightly,throw some stealth lube in there..before you button everything up..throw some more lube on the ring gears..

fastharry™

iTrader: (4)

well,to say I am AGGRAVATED is to say the least....




I'm installing LUNSFORD hinge pins and TI balls......

GUESS WHAT!!!!!!...the upper hinge pins are undersized...there's now a ton of slop in the upper arms...''



so I go to install teh pivot balls.......

Not only are the threads that screw into the arms WAY undersized(I mean,they are off over 5 thousansths....they just about fall out by themselves....)..

but the pillow ball themselves are undersized........they are absolutely un-usable.......

there is so much slop in the car,its ridiculous......



Does any company even check anything any more?!!!!!!!!!

I'll call them tommorow.....and I will light up the phone line...