B3350 Turbo Boost Pressure - Solved!

[Travis616]

Hello, does anyone know what the boost pressure is supposed to be on a B3350? I'm guessing 5psi or so because that seems to be where I can hear the wastegate open when pressurizing it but hand. I only get 2psi at w.o.t and the wastegate seems to be fully closed - going to pull the turbo and see what's up but thought I would check here first. Travis

 

[ptsg]

Did you check the pressure with a load on the engine or just at wide open throttle? I really doubt you'll get full boost without a load on the engine.

 

[Travis616]

Did you check the pressure with a load on the engine or just at wide open throttle? I really doubt you'll get full boost without a load on the engine

I didn't think of that, it was just sitting stationary with no load. I need to set up a little better pressure gauge and then could get it working driving around least

 

[ptsg]

Maybe you can do it stationary by pressing the brakes and trying to move in high range.

 

[Travis616]

Just under 4psi is the highest I saw under full load so I guess the turbo is coming off for inspection. I did check that it turned smoothly and no visible damage on the intake side. Not sure if the wastegate would be partially held open from carbon? There were dpf issues with this tractor but that has been rectified so wondering if that has led to the current situation?

 

[Jerry/MT]

Just under 4psi is the highest I saw under full load so I guess the turbo is coming off for inspection. I did check that it turned smoothly and no visible damage on the intake side. Not sure if the wastegate would be partially held open from carbon? There were dpf issues with this tractor but that has been rectified so wondering if that has led to the current situation?

check your air filter and intake manifold for obstructions first

 

[Travis616]

Will do, thanks. I gave them a quick look but will check a little closer

 

[MHarryE]

What do you think you should see? My F250 Powerstroke only gets 8 psi boost pulling heavy load up a hill. An Allis-Chalmers 7.0 liter would get 26 psi at 220 HP, but when we were bought out by Deutz and needed to switch to Deutz engines, we only had 7psi at full load. Operators used to running by boost on A-C powered combines found the boost gauge useless on Deutz because of no sharp rise when running max power. Is it possible 6 psi is your boost peak? I checked the WSMs for my 3 Kubota tractors. They give no info on boost. In fact, they barely mention turbos. If they leak oil externally, tighten bolts. If the blades hit the housing, replace turbo. That’s really the full depth.

 

[90cummins]

Hello, does anyone know what the boost pressure is supposed to be on a B3350? I'm guessing 5psi or so because that seems to be where I can hear the wastegate open when pressurizing it but hand. I only get 2psi at w.o.t and the wastegate seems to be fully closed - going to pull the turbo and see what's up but thought I would check here first. Travis

I have to ask why you think there may be a problem?
Can you elaborate?
90cummins

 

[Travis616]

When comparing to my other tractors (TC30 & TC33) it doesn't have the same power although rated basically the same. It specs out at the same pto hp as the TC33 and two or three more than the TC30 but heading up a hill it cant hold the same speed and just seems a little lazy in general - not terrible but not right either. If i use a hand operated pressure tester it seems the wastegate opens around 6psi, I would think that the turbo should build that and more otherwise there would be no need for the wastegate if the turbo is only capable of building 4psi. In my mind it should be like an alternator (turbo) where unregulated it can make 100v or more but the regulator (wastegate) holds it to 14v.