Turbo trouble shooting

[nytroboost]

Sled is a Nytro with a turbo kit (Gt2554R) front mount. Sled does not want to make boost gauge indicates maybe a pound of boost. Checked waste gate actuator and it is closed. BOV is not open. Checked all lines and can not find any leaks. Have not pulled exhaust manifold but can not hear any leaks. Turbo spools down normally after shutting down (no strange noises or binding). Pulled tube going to intercooler seems to work like a big hair dryer moving lots of air. No idea what A/F ratio is but will install my Prologger this weekend. Maybe I need to pressure test my intercooler ? Any other ideas how to trouble shoot this thing. Trying to get a head start on dialing this sled in before our season starts ( two months away).

thanks

 

[canuck5]

Does the machine run like it's bulding boost at all? Check exhaust manifold would say this would be biggest culpret if you have some miles on it. Leak down test to start, haven't done one myself but with some creativity should be able to trouble shoot it if something is leaking lots. Basically isolate system and pressure up couple psi and listen for leaks.

 

[BlueByYou2000]

Also if you are testing this on a jack stand, your likely not to build much boost. You need to load the motor.

 

[T-Nytro]

Also if you are testing this on a jack stand, your likely not to build much boost. You need to load the motor.

He is right on the money. My MCX Nytro will build maybe 1 psi of boost if I am lucky on the jackstand. Ride it and it will build 14psi no problem.

 

[adrenalator8]

T-nytro is correct for a turbo to make boost it need load and when your throttling it on a stand there isn't enough load .

 

[rxrider]

I'll second that - same thing happens on a rearmount RX-1 with MCX turbo, not much boost if any on the jackstand. Take it out on the grass and give it WOT and see what happens before you tear it to pieces for no reason.

 

[nytroboost]

Tried it out on the grass already and it was sluggish with very little boost at WOT, so I will keep searching thanks for the suggestions

 

[rxrider]

Do you have a WBO2 (AFR) system installed, your sled may run WAY fat almost stalling the engine, would cause it to build little or no boost, it will also be very sluggish down low until it clears up if it does that is.

A huge air leak in the charge tube will drop boost faster than it can be built, a smaller air leak will allow for boost but you will loose pressure again.

A small exhaust gas leak will make the sled respond slowly and sluggish from bottom rpms, it will still build boost but may not build full boost, a large leak may cause little to no boost to be built.

 

[nytroboost]

I am installing a prologger (wideband logger) this weekend. I think thier is a good chance that air fuel ratio may be the problem. Thanks for the input.

 

[nytroboost]

wastegate controller seems to have been the problem, installed an electric boost controller and the sled will even make plenty of boost on the stand ! should be alot more fun to ride now

 

[rxrider]

Glad to hear you figured it out