1QwkSport2.5r

What about running on a resurfaced road (sprayed with oil and covered in gravel)? Do the foams tear or chunk out easily?

Also, wanted to pick the Jato experts' brains. The brake setup on the jato sucks. My brakes blow. There's a brake hop-up isn't there? I haven't pushed my jato past 55mph because the brakes take awhile to work. My jato was originally a 2.5 if that matters.

mattster1971

The brakes do suck. There are a couple upgrades out there. The dual steel disk with the fiberglass pads works fine. More stopping power than you will ever need but some like the carbon fiber pads. The foams will not be good on that surface. Must be smooth asphalt or concrete.

1QwkSport2.5r

So foams for baby butt smooth pavement, what on slightly coarser surfaces? Are road rages worth a snot on Jatos? I had a pair for my 3.3 Rusty, but they spun too much with the stock single speed tranny. I've always liked dirt hawgs on the rustler for off-road as they hook good but wear out slowly.

I'll do some looking around on that brake mod. The whole mechanism looks cheesy.

1QwkSport2.5r

I had another question... What is the highest clutch/spur you can get for a Jato for fast top speeds?

gracie666

hey guys im new too jato 3.3 I did the break in process,i have the dash board on my iphone and the temp is reading 150c but in not able too drive more than 15 too 20 cause the shop floor is too slippery could this be y im getting high temp

gracie666

do you know anything about the temp what it should run on the jato

mattster1971

I am not familiar with Celcius, do the conversion to Farenheit. Running around 230 max F . You get above 250 and you are risking rod split on the 3.3 or worse. They also sell aftermarket connecting rods to remedy this weekness in the 3.3.

Cowboy420

Most nitro engines are fine up to 280-290 degrees, my last nitro engine ran like a champ at 285.

1QwkSport2.5r

The rod doesn't split because of too hot a temperature, it happens from being too cold. The hotter the engine temp the more the liner expands and gets 'straighter'. Too hot and the engine will quit.

So much misinformation out there, it's no wonder so many people have problems.

mattster1971

I beg to differ but I have had rods splitting in half on two different 3.3's because I was running to lean and overheated the engines. I have since learned my mistake and run very rich to keep temps down. And I would not suggest running a 3.3 at 285 unless you want trouble. Never heard of a cold split rod.

1QwkSport2.5r

Lean mixtures are hotter mixtures which makes the liner over expand and when this happens the piston seal against the liner gets weak and the engine quits. A truly overheated ABC engine generally just quits and won't restart for awhile. If the liner is cold, the taper of the liner doesn't fully straighten out and in turn the piston gets hammered into the pinch adding more strain to both ends of the rod and the crankpin. A lean mixture reduces the oil film in the rod bushings causing the wrist pin and crankpin to hammer the bushing of the rod fatiguing the metal and eventually causing it to crack and sometimes split. Add to the fact that many 3.3's are extremely tight when new just adds that much more friction and increases the need for adequate lubrication. If temperature isn't the leading cause of failure, poor lubrication probably is. PAG synthetic oils used in today's fuels have a poor film strength and IMO inadequate viscosity to keep the piston from contacting the liner. I suspect fuels with low or no castor oil to be a major contributor to poor lubrication especially since most car fuel has less than 12% oil. The margin of error in fuel mixture is much much smaller with low oil content fuels like the 8-10% race fuels. Now don't get me wrong, most fuel isn't "bad" per sé, but care needs to be exercised when running a tight engine in. I break-in on 16-18% castor oil and after about 1/2 gallon of this fuel I switch to either 20/10 or 30/8 fuel which is a 50/50 blend of castor and synthetic oil.

Tuning an engine based on temp is a sure fire way to either have poor performance or damage the engine. Start out rich, lean it for max performance, Richen 1/16-1/8 turn and leave it. This is how I treat and tune my engines and somehow the rods don't split. But then again I don't use the swill the hobby shops sell so maybe that has something to do with my lack of trouble. But hell, what do I know? Most of you guys know so much more than I do, so who am I to judge.

mattster1971

Okay well thank you for that long technical explanation. I will still disagree with you. I have never run my engines in the cold. The rod split down the center and there was discoloration of the rod and the piston from overheating. I was told by numerous people on here and in the hobby world that this was caused by running too lean and therefore too hot. Sure this means lack of lubrication that lead to the piston seizing which caused the rod to split but its still due to running lean and running too hot. Period.

1QwkSport2.5r

Running hot wasn't the cause of your failure, lack of lubrication was. If the engine was properly lubricated it wouldn't have galled the rod and caused it to fail. Plain and simple. Also, running an engine "in the cold" is not the same as running the engine too cold.

Just because a hundred people "in the hobby" tell you something doesn't make it right. But I won't argue with you, clearly you are more of an engine man than myself so my hats off to you.

Buttonmanb

Did you guys check this rlchobbies.com out. I have been using them to make me all kind of custom jato stuff. They have a new exstened big block chassis that is killer. I know alot of people switched to there stuff and there flying.

nastyboys727

i run mine around 255 or 260 been best for me

Cyclone44

Hello everyone,

Long time lurker (in helis and cars) but first time poster. I bought a 2nd hand Jato 3.3 about 6 weeks ago. Slowly Ive been upgrading bits here and there, ie wheels/tyres, added lights. But Ive developed a problem with the brakes. I installed a new brake pad but its not working. There are 4 screws (im hoping its just 4) that need adjusting but I cant seem to find the right info on how tight or loose they should be. Ive added a picture which will make it easier to understand. Sorry Im not great with the technical terms for the parts yet lol

Could anyone help me get this thing working right as Im pulling my hair out.

Many thanks!

I had been over the field earlier that day which is why its covered in mud

1QwkSport2.5r

Tighten those screws (C and D only, A and B are supposed to be tight enough to still allow the linkage to move and have no bearing otherwise on how well the brakes work) and using the radio, test the brakes with each 1/8-1/4 turn (once they're close to being snug). These screws act like the brake caliper in a full size car; too loose, no brakes. Too tight, no moving.

Cyclone44

Thanks for the reply. Ive adjusted the screws but I cant try it out as Ive now got another problem......I have no power. It was fine one minute, gone the next

Ive checked the wiring and nothing is loose, and batteries are new! Aarrgghhh, this hobby is sooo frustrating.

1QwkSport2.5r

Bypass the switch. Plug the battery pack directly into the receiver. It's not uncommon for the switch to get corrosion inside. It can be frustrating if you let it be; use the process of elimination to sort through a problem. Start with the most obvious and work your way towards the more complicated/involved troubleshooting.

Cyclone44

Thanks. Plugging the battery pack straight into the receiver indeed works, so I have a dodgy switch. Dont know wether to laugh or cry

I need to replace the 'system wiring harness'. This is fairly cheap but looks like I need to take the car apart to do it?


*edit* Looking at it, it doesnt look too bad. Its just a case of pulling the wires through the holes, but things need loosening to do it....I think.

*edit* #2 Ive undone the screws to the servo and there's enough room to slide the old wires out. Switch now removed, a new one on order. Just have to put it all back together now, seems easy enough. Watch this space

1QwkSport2.5r

Glad you got it sorted out. Easy fixes are the best fixes...

Cyclone44

I thought Heli's were a nightmare for going wrong, this is on a new level

Thanks again!!

Cyclone44

New switch installed and the car is working fine . Only downside is I damaged a wire from the battery pack so Ive had to order a soldering iron kit. Not that bad as im guessing Ill be using that a lot over the months.

And I think Ive sussed out the brakes.

Thanks again for the help!!!

1QwkSport2.5r

Never a problem.

quietnas1

Anyone having issues with brakes, here is a link that should help.
http://www.rcuniverse.com/forum/rc-n...thread-14.html

Second post from the bottom.