Help identify please.

[czappmw]

Just picked up a t maxx. Need help identifying it so I can pick up the correct air filter and glow plug. Is there any difference between the 2.5 and the 3.3 motor? I'm searching and all I see is references to the chassis.

Sent from my SM-G986U using Tapatalk

[Double G]

Looks like the 4908. RPM arms, forward only transmission, Chevron tires (at least one installed backwards - the rears are correct direction), alloy bulkhead(s) and painted front bumper(?). Use the Support button above to search for 4908 or 4907 to pull up the manual and exploded views; you cannot go wrong with either of those to get your part numbers.

[olds97_lss]

I believe the 2.5 and 3.3 both have the size on the side of the crank case. The 3.3 is taller, but without having them both, can't really see it.

From traxxas.com https://traxxas.com/products/parts/5407


From another

[Nitronaught]

Looks like the 4908. RPM arms, forward only transmission, Chevron tires (at least one installed backwards - the rears are correct direction), alloy bulkhead(s) and painted front bumper(?). Use the Support button above to search for 4908 or 4907 to pull up the manual and exploded views; you cannot go wrong with either of those to get your part numbers.

+1

The bumper is a painted RPM front bumper. Pretty sure that is an upgraded 2.5 TMAXX, I bet the turnbuckles and axle carriers are for the original 2.5 TMAXX setup (before Grey plastic parts were used).

The 2.5 and the 3.3 use the same glow plug and air filter. I like using a 1/8th buggy filter myself and the Duratraxx LC3 plug with 30% nitro...

[czappmw]

Its a 3.3. I got it to fire but it won't stay running for more than 30 seconds. Doesn't seem like its pulling fuel very well.

Sent from my SM-G986U using Tapatalk

[Nitronaught]

Its a 3.3. I got it to fire but it won't stay running for more than 30 seconds. Doesn't seem like its pulling fuel very well.

Sent from my SM-G986U using Tapatalk

Check your fuel tank seal. Fuel lines and pressure line from exhaust for any leaks. Are you finding any fuel on the deck of the chassis by the tank?
If not you may have a worn piston & sleeve. Check for a good pinch at the top of the stroke. With the engine cold, glow plug in tight and facing the flywheel rotate it counterclockwise you should feel a pretty good amount of resistance. If you find it easy to rotate the compression no longer exists, time to rebuild or replace.

If the compression is good, fuel system clean, check head bolts are tight (do it in a star pattern like a 1:1 car tire). Return the needles to factory settings, use a fresh glow plug and go from there. Follow this tuning method. If this does not work the issue is not your tune.... https://forums.traxxas.com/showthrea...ul-Tuning-tips