JATO FEVER

With good break in and no overheating how many gallons of fuel before my jatoengine is worn out?

nitroholic

I got about 4 beating it all the time.I ran only Odonnel 20% speed blend,no traxxas blue BS!

JATO FEVER

wow only 4? I hope to get more that . Im on my third gal now. In another truck that doesnt go as fast will you get longer life?

nitroholic

Also rebuilding one to be new again i just got a new one bidding on ebay.By the time you rebuild it's almost the same price to just start over.I did get a good deal though and i just happen to win the auction.That was my Jato.I have some ways to get your jato to go 75+ almost 80.I found the key experimenting.Only problem was is the engine does labor a bit of the line cause it's all top end.I had mine geared unbelievably crazy.The spur i ran is now discontinude i think.I kept mine. I know if i put them up for sale they'd sell quik.I thought about it seeings i sold my jato,but i do miss it sometime and might use the same ratio in another one.Engine does take a beating with it geared like that though.

1QwkSport2.5r

Barring any cold break-in runs, I see no reason why a Traxxas engine wont get 7-10 gallons before the piston and liner end up being worn out provided its not tuned to absolute peak screaming rpm and good fuel with some castor is used. I have one 3.3 that was in a T-maxx for 3 gallons and now a Rustler for another gallon and the piston will still push the sleeve out of the crankcase with the head off.

I use 10% oil for going fast, and 12% for just bashing around. 16% oil for break-in, and all 3 blends use a 50/50 blend of castor/synthetic.

I think Traxxas engines really aren't as bad as so many people make them out to be. They need to be broke in hot, otherwise the tight pinch beats the conrods to death a lot of times.

JATO FEVER

Does moving your piston to bottom dead center when not running help add life?

1QwkSport2.5r

I doubt it "adds life", but it will help let the leftover fuel residue evaporate in the crankcase and lessen the chance of rust or corrosion forming. I do it on all of my engines although the majority of my engines run on only 5% nitro so I don't worry about it too much. If your fuel has no castor oil in it, use after run oil and lots of it. I use Dexron III transmission fluid and a dribble of seafoam for ARO if I'm going to store an engine for more than a month.

SLAYERDUDE

The theory of BDC is the engine not cooling and letting the sleeve contract on the piston at TDC causing the sleeve to get "stretched out".
Main cause of 3.3 failure from what I've seen is the conrod splitting like a log, this is because they used the 2.5 rod in the 3.3.
There's a company (maybe 2) that makes a beefier rod for the 3.3.

Preheating may prevent this, but the Crapxxas 3.3 is the only engine I've seen repeatedly split rods down the middle.
In fact, I've never seen any other engine split a rod like that, just google images for 3.3 split rod....

JATO FEVER

WOW those pics are scary. Who makes the tougher rods? gonna use one when i need a rebuild. Thanks for all the info.

mattster1971

You have two choices. Davis Diesel makes one, they have a good reputation. The other choice is Rb mods, also good reputation newer company. I think the rb conrod looks sexier but who cares its inside the engine. Anyone have testimonials on either one?

JATO FEVER

The davis diesel rod looks tough. i could not find a pic of the rb rod . what about piston and sleeve will stock be fine or go bulletproof there also?

mattster1971

Do they make a different replacement piston and sleeve? If so, I am not aware of it. The RB Mods version is listed on their website. AND they have a heavy duty shaft as well, looks so nice. If I wasn't just using this sucker to run up and down my street I might invest in all these upgrades. For now, I will have to be happy with the rebuild I did about 4 months ago with a new sleeve piston and traxxas conrod. I will replace with one of those other conrods if this one goes out again, I just hope if it does split it doesn't beat the crap out of my piston skirt again, I would like to salvage some parts.. ugh. If I had the funds I would take a stock 3.3 get RB to replace the shaft and conrod and do their magical porting. Then I would replace the carb with something a little throatier and up the exhaust for more capacity. Maybe even change the cooling head at different seasons to get better cooling. I can't really justify the cost of the new 3.3, plus the RB modding and porting, plus new carb, plus larger exhaust so I can irritate the neighbors a little more. Lol

westoakmech

I run the davis rod in my 3.3, no problems.

On2_n_On4

some people do... but I would spend money on a 3.3 (read my sig.)
If you do, buy new bearings while you are it.

On2_n_On4

part # just in case, I think they were like $25 or $30.

1QwkSport2.5r

If you want to save yourself $20 or more, buy your bearings from RC-Bearings.com. You will get the same bearings from RCB as you get from Boca, except the price is much much nicer.

Front bearing, metal shielded, less than $4. 7x17x5mm
http://www.rcbearings.com/7x17x5-697zz-bearing/
Rear bearing, metal shielded, less than $4, 12x21x5mm
http://www.rcbearings.com/6801zz-12x21x5/

I've ordered numerous engine bearings from Paul at Rc-Bearings.com, and I've never had a problem. Usually ships the same day as you order, and shows up at your doorstep in 2-4 days depending on where you are. RCU members can use promo code "rcu" for 5% off, too.

I use the ZZ style (metal shielded) bearings in any engine I replace bearings in. If there is a rear bearing thats open on both sides or shielded on only one side, I will opt for that otherwise the metal shields allows sufficient lubrication into the bearings if you use a good fuel with enough lube in it.

Just my 2 cents.

CarGuy7a

Mine lasted about 3 gallons on TRX fuel. Never split the rod, the piston/sleeve just wore out. It would get to 200°F then just stall. I will say the 3.3 is not the best motor in the world but really it's just an RTR motor and that's all. Just a motor to get you going in the hobby.

I now run an OS 21TM and it's a great little motor. Very easy to tune and runs like a beast.

countilaw

I don't know if you are aware of the Traxxas upgrade program.       Take your   2.5 or 3.3  to any HobbyTown USA  and with a  $115.00 plus your old broken engine,  get a  brand new in the box  engine.   No questions asked.   Call your local  Hobbytown USA and get more details. 

Frank

JATO FEVER

I have seen the traxxas trade in program. But when my 3.3 goes i am goin to rebuild myself. Just something i want to learn. I want to know my car inside and out. If my rebuild sucks then tradei n it is!!!

peropett

I hope to get more that . Im on my third gal now.

JoeMaxx

Yes it does add life to the engine.I have beendoing it for years and my Traxxas2.5r and 3.3r are about 8 years old now and I have used this for about 12 years.

Some might disagreewith this thought of mine and I have never had it happen from running a semi rich mixture of fuel. I use a temp gauge when I tune each day and attempt to keep my temps below 260 degrees on my engines. Do not use a temp gauge for tuning it is just a reference point I use because outdoor temps and barametrics andhumidity is different each day. Some days my engines will run peak performance at 260 and others they run just fine at 200 degrees. It is the sound and smoke trail that I ultimately use for tuning each time I go out to play.

Link inserted herehttp://traxxas.com/sites/default/fil...ningcard_0.pdf

The only reason that apiston shaft will break isbecause of excessive over heating of the engine multiple times. Here iswhat happens and why. The 2 Stroke engines require oil to lubricate the bottom end shaftbushingsand piston walls. When the engine is run too lean many times over and over again it creates friction on the piston sleeve walls and weakens the piston shaft eventually causing it fail and break.

daviomaron

The spur i ran is now discontinude i think.I kept mine.

outlawbrett

i have ran mulitple 3.3's and have never had a rod split. ive had my problems with them. usually leaks. i have only got one of them that didnt have a leak. nothing that sealing them up doesnt cure. i have numerous brands of engines. big an small blocks. i like the 3.3 when u ditch the TRX carb. its way to small. i have a modded 3.3 with a losi carb an THS exhaust an it rips. like being said earlier, the 3.3 likes heat during break in.