traxxas 3.3 engine issue and old plastic issue

[HCN]

hey guys!!the wife and i were out at the local park running our traxxas vehicles today. I think the 3.3 died in my wife's t-maxx and mine broke after 5 minutes in three different spots. the history... both of our trucks are over 10 years old. the t-maxx was wrecked hard and broke multiple parts (carb, suspension, chassis parts and the front bumper) before it was put up for a looooooong time. yes, i cleaned and oiled the engine and cleaned the rest of the truck up before moth balling it. i recently revived the maxx with new parts. fought air leaks with old rubber lines and tank seals so i replaced em. so finally got the maxx running like new again and got tired of being confined to our little street to run it so we went to the park. at first it sounded odd, can't really describe it but a red flag went up in my head. tweaked the tune a bit, thinking it was out a hair, and it sounded much better. ran about three and a half tanks of fuel thru it then the engine started to sound labored and lost power very suddenly. at full throttle the truck moves at walking speed at best. I've read these 3.3s are good for about 3 gallons of fuel before they crater. temps were about 220-230. blue smoke was consistant with a good tune. we took the body off to allow better airflow while running out in a soccer field area doing a lot of high speed runs to and fro. i went over the rubber parts looking for a airleak but found nothing obvious. trans and diffs move easily. being my wife has had this truck for such a long time i can't remember exactly how much fuel we have run thru it. it was broke in exactly as traxxas specified and i have always kept on top of the tune. any ideas? old plastic... my truck is also the same age(2.5r rustler) it runs for 5 min before something plastic breaks in the past 3 runs over very minor crashes. crashes that this thing used to shake off. my question here is do any of you guys have older trucks where the plastic seems to be brittle? I'm replacing the old rustler one part at a time and after today i was starting to think its not worth it. sorry for the long post. wanted to get all the info in. thanks in advance!!

 

[Certified Mike]

Is the 3.3 reaching full high rpms and is not going fast or has 'full throttle' been redefined?I am thinking slipper clutch or bell housing clutch as first targets to check. If it's the engine not running right, it is likely going to run deeper than that.
As far as the plastic parts issues... I have a Revo and a Jato both of similar age. Mine also went into storage for some time and have been brought out and run (hard) since then. The Revo needs a trans gear or 3 replaced (my fault) which I am working on as I can right now. The Jato runs strong as the day I got it and is as tough. No easy snapping parts or the likes.
I have a few other manufacturers of electrics that I take out every now and then and these also take a tough roll or hit on occasion. (Honestly, I am careful with these as they are old and rare. Parts are tough to find and expensive as hell!!!)
Anyways... My question to you is... What are you breaking? Is it arms and towers etc? Or are you chewing up gears and shafts etc? I am wondering if the car was washed in harsh chenicals, was stored in extreme temps, any other odd thing that may have happened along the way???
If it's drivetrain stuff, breakage happens (so to speak). I'm not saying that I would expect to rebuild the car, piece by piece BUT replacing old, high stress components wouldn't surprise me at all.
I don't think age alone is the culprit

 

[HCN]

the 3.3 does not rev up. sounds... odd, it sounds a lot like an outboard boat motor that is idling. it burbles, if there is such a word. can't really describe it. i was hoping for an idea of where to start. think i will start with an engine inspection tomorrow. as far as the parts that have been breaking its the suspension and driveshafts, which of course take the brunt of most crashes when bashing. i havent hit anything hard which is why I'm asking about old plastic. i have never put anything on the plastic parts but some wd40 to help get the greasy mess associated with running nitro. it was stored on a self in my garage so no temperature extremes when they were not being used. perhaps it is all a run of bad luck and the parts were already damaged and just happen to be breaking at the same time

 

[Certified Mike]

If at all possible, post videos of the engine issues. I have no idea what the actual success rate is for us and how many ppls car we have helped diagnose and get running but I will say without question or being cocky that we are VERY good at getting ppl going again after they have some down time or a meltdown. The ppl here are all very bright (for the most part) and always willing to help out. So yeah, vids and maybe pics of what's snapping... My personal guess with the plastic is likely as you have said, they are beat up and possibly even partially broke from a previous impact or 10. If you find you are replacing the same parts repeatedly, I would be concerned about possible bent metal chasis parts putting stress on the plastic.

 

[cbaker65]

We atleast give the folks a little spark back!....

Is the 3.3 reaching full high rpms and is not going fast or has 'full throttle' been redefined?I am thinking slipper clutch or bell housing clutch as first targets to check. If it's the engine not running right, it is likely going to run deeper than that.
As far as the plastic parts issues... I have a Revo and a Jato both of similar age. Mine also went into storage for some time and have been brought out and run (hard) since then. The Revo needs a trans gear or 3 replaced (my fault) which I am working on as I can right now. The Jato runs strong as the day I got it and is as tough. No easy snapping parts or the likes.
I have a few other manufacturers of electrics that I take out every now and then and these also take a tough roll or hit on occasion. (Honestly, I am careful with these as they are old and rare. Parts are tough to find and expensive as hell!!!)
Anyways... My question to you is... What are you breaking? Is it arms and towers etc? Or are you chewing up gears and shafts etc? I am wondering if the car was washed in harsh chenicals, was stored in extreme temps, any other odd thing that may have happened along the way???
If it's drivetrain stuff, breakage happens (so to speak). I'm not saying that I would expect to rebuild the car, piece by piece BUT replacing old, high stress components wouldn't surprise me at all.
I don't think age alone is the culprit

You should be able to find some RPM a-arms an some other parts in that brand for that truck on E-bay!
RPM's stuff is better an is more flexible than the original parts!...

 

[olds97_lss]

Since it's not too tough to do, might be a good idea to tear the engine down and inspect the internals. Could have a fried bearing or your con-rod is dying. The 3.3 is pretty well known for shelling con-rods, but it's usually pretty abrupt and destructive because the rod splits in half.

 

[Certified Mike]

Wondering if you have seen a change in the way it runs when the tank is full and after it drops below a certain level (half tank)?

 

[Certified Mike]

Verify all linkages and the servo itself are operating correctly and aren't hitting anything to prevent WOT on the carb. Make sure there isn't some little setting in the radio that hasn't cause an issue as well. When I took my Jato out of storage, the radio setting in the steering somehow went into 'servo reverse' mode.
The bearings are a likely cause of issues as @olds97_lss mentioned. Your truck is especially vulnerable where this sat for a while. Even though you oiled etc prior to storage, the fuel can be difficult to displace in the bearings. Once the fuel evaporates and the castor oil is left, it will gum up leaving the bearings goo'd up and locked into place.

 

[Certified Mike]

Btw, for future reference, I have heard conflicting reports about using wd40 on plastic. Some folks swear by it as a cleaner, others swear it degrades the plastic over time. One way or the other, if I did ever use it one my rigs, I would make 100% sure to clean it again, thoroughly with a good degreaser like simple green or the likes and be POSITIVE that ALL the WD40 was cleaned entirely off of everything! I don't use it on my rigs and with this post in mind, I don't think I ever will. Carb and brake cleaner can also destroy plastic as well as some things you may not ever think of, like bug spray with DEET in it. So yeah, think back and see if this rings any bells.

 

[Scalded-dog]

I have a hand me down emaxx and a ofna nitro that sat unattended in a unheated garage for a bit over 10 years. Been running them alot lately and nothing has broken that is plastic. I personally havent had trouble with plastic aging and getting brittle.

On the other hand a decade unattended was rough on the fuel system of the nitro. Carb all but glued itself shut and the engine had goo and goobers everywhere. I didnt even try to use the carb (replaced it with used flea-bay carb). The engine on the other hand got tore down and cleaned. I would think that a oil goober blocking up any given needle or port would cause it to act all sorts of screwy.

 

[Certified Mike]

Lol!!! Yes, a tiny bit of old 'oil goober' in just the wrong spot will raise hell in an engine. Where there aren't a lot of moving parts or a complicated fuel delivery system involved here, it doesn't take much to throw the 'fuel injection' off.

 

[olds97_lss]

My jato is 10 years old to me and still has the original RPM arms, bumper, and stock front tower, axle carriers on it. I just ran it yesterday after converting it to electric. Not really noticing anything being rigid or brittle on it. The rear tower breaks a lot, but that's just poor design. My savage is 5 years old to me and still running original arms, towers, bulkheads. I beat the snot out of it a couple weeks ago and it's holding up fine as well. I've replaced c-hubs/axle carriers over the years, so those aren't original. The steering bellcranks are though.

 

[Certified Mike]

Does anyone with any of these older cars use wd40 or any other type of cleaner religiously? If so, what do you use if it's not wd? If you do use wd, do you clean that off with something else as well?