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TMX 3.3 4909 Rear Center DS Replacement

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Hey Guys, I looked through some older tmaxx treads but didnt see any Drive shaft replacment threads.

Heres my story, I was running my tmaxx out in the street and in my front yard when i noticed a big performance change so i hit the gas a few times on the grass to see what the issue was when i noticed only the front wheels were pulling. I shut it down and flipped it over and noticed that i threw a pin in the yolk on the rear center drive shaft transmission side.

Being the total rookie on this i just wnt down to the hardware store and purchased some piano wire that was a hair to big for the receiving hole for the pin. With a drill and some sand paper i was able to get the piano wire the perfect size for the hole in the yolk. I was able to get my new homemade yolk pin in snug with the assistance with a small ball pein hammer.

The next day i took it out for a spin to see if it was going to work. So i fired it up and did some runs up and down the road with minnimal throttle and was running fine so i made another pass and was really getting on it when the pin came out again only this time it came out and lodged into a smooth round bell on the back side of the rear gear that meats up with the transmission gear and it fliped over in the road.

with all the above drama this brings me to you guys lol, so this is where i stand. I ordered a new set of center drive shafts from RC Super Store heres the link to the exact ones i orederd.

http://www.rcsuperstore.com/Traxxas_Steel_Center_Drive_Shaft_Set_T_Maxx_3_3_p/tra4949r.htm

I took the old rear center ds off yesterday afternoon in which i had to drop the transmission by taking the 8 or so screws from the bottom rail. I then was able to get the set screws off then removed the drive shaft and yolks. Upon further inspection i found that there were set screws that held in the yolk pin WALLA thats why i threw it lol. I had no idea that these trucks were that intricate down to having set screws to hold the yolk pin.

If you are still reading at this point i appoligize for the lenghty post.


My question is once i replace the drive shafts is there anything i need to do special in order to remount the transmission. I do not want to create more problems trying to fix my original problem. I am looking forward to actually running this thing for a few hours in one day with out major malfunctions.

Here is a pic of the original drive shaft
 

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Nope nothing special, recheck your Clutch bell to spur gear mesh, & be careful not to over tighten the trany screws as you don't
want to pull the treads out of the case.

The pin coming out of the MIP shaft is a coming problem, be happy it didn't shell the trany gears too boot.

The 4949R CVD's shouldn't give you any trouble on the install.
 
To check my clutch bell to spur gear mesh do i just roll the spur gear with my finger for any resistance?

Also I dont know what MIP stands for lol, its my first go around here dont know all the abbreviations yet.

Is there any type of recommended thread locker that i can use like loctite, i wouldnt think you could use the industrial strength stuff on such small screws due to the fact you could never get them back out with out stripping the hex head.
 
To check ur gear mesh just use the paper trick,put a slice of paper between the two gears and slide the engine over and tighten,u should wind up with an accordian looking piece of paper when done correctly,...."mip" is a company that makes "hop up parts" ..nitro 4910 was refering to the center shaft made by them,........only use the blue threadlocker,plenty of us here use it.
 
Your original shaft is a good one that is made by moors ideal products (MIP):
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDXN8&P=7

They were the ones most would buy back before revo-spec axles came along.

Just make sure to use good locktite on the set screws. I proffer the gel/stick loctite to the liquid as it seems to do better on the small screws we use for RC.
 
How to "bulletproof" your MIP CVD's
http://www.hpiracing.com/walkthroughs/rebuild-cvd.htm


The easiest way to learn is by putting a strip of paper between the gears.

Adjusting the Spur Gear/Clutch Bell Gear Mesh page 25 in the T maxx manual:)
http://traxxas.com/sites/default/files/4909_manual-2005.pdf
The ideal spur gear/clutch bell gear mesh for T-Maxx 3.3 is 0.1mm.

To set the gear mesh, place a strip of standard letter/A4 size copy or printer paper (about 0.1mm thick) between the mating teeth.

Loosen the four engine mount screws from the bottom side of the chassis (see image) and slide the engine mount up to push the clutch bell gear
against the spur gear so the paper is not too tight to pull out or too loose that it will fall out.

Tighten the engine mount screws securely.

When the paper is removed, you should feel only the slightest amount of play between the gears (almost none) and there should be no
binding or friction.

Spurgearmesh_zpse2aed062.webp
 
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WOW! thanks for the great info, does MIP sell the replacement pins and set screws? if so i will go ahead and install the new ones i ordered and then bulletproof the MIP's for back ups.

The paper trick for the gear mesh looks pretty simple and to the point i should be able to handle this.

I got the truck used so i have no clue what is stock and what is upgraded, I will post a pic of the truck later today maybe you guys could let me know what i have.
 
Well i got it all together and about to run a test trial in the back yard once my quick starter charges, got my fingers crossed.

Thanks Nitro4910 for all your advice, i did in fact have to adjust the motor into the spur gear. The paper trick worked well.
 
WAhooo!!

It worked well as far as i could tell being in the dark, i ran about an 1/8 of a tank through seem to run ok and started with ease even though the temp high 30's and when i put it up it was in the 80's. Hopefully i will have some day light to run it tomorrow aftr work.

Thanks, Jason
 
Good deal!

Do remember that you will need to tune it to the ambient temp, it will need to be richer then your summer tune
with the cold dense air getting packed into the engine.

If you have trouble keeping the engine above 200°F you can put a wrap or two of aluminum foil around the
cooling head & poke holes in the foil till you get the right amount of heat retention.

Have fun with it!:)
 
Thanks again Nitro4910, i ran the first tank through too rich i had oil all over the exhaust and body. My second tank i had it dialed in pretty good was pullin wheelies from a dead stop and and while rolling. I really like to play with the tunning even though i did get it hot 2 times. I dont have a heat gun yet so i used the gross spit and sizzle test lol, now that i think i got this somewhat reliable now, i am going to purchase a temp gun just to be safe.

Any recommendations on a cheap but reliable temp gun?
 

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