3406 b power problem

have you cheched your charge air cooler and boots? boost shouldn't fall off like that i don't believe. Seems kinda low at 24 PSI peak also. I know our 425's make around 30-32psi. not sure about your 350 though

 

Really? I've never seen above 25psi on my B model.

 

Should a 3406 B smoke under full boost when fuel is maxed out? I adjusted the pump of a friends W 900 but it doesnt seem as powerful what some Cat freaks write about turned out B models. Everything is stock so I think a full rack travel should smoke like *ell.

 

3406B's that smoke depending on serial number can be the timing advance slipping. Another issue to consider is when was the last time the overhead was run.
The older the nozzles get on that truck the more fuel the nozzles will put out compared to the new electronic injectors which decrease with time.

The other outside possibility is the injection pump bonnetts leaking pressure internally which decreases the pressure of the fuel to the nozzle.

If this is the case you can turn the pump up all you want, and it won't run worth a darn. I should know I spent a week on a truck with a 425 HP engine for three hours at a time because that was the only time the customer could give me.

 

This is some special low rpm 400hp engine imported from Canada. It revs only 2000 rpm when high idle screw is thrown away. Maybe it has some very small nozzles? It pulls much better when we threw both fuel screws away but not as well as we expected.

 

The governor has a different spring and rack shim pack that prevents excess speed. This is a Canadian fix. They figured operators would do just what you did. You will have to have a different Governor control group installed to include both springs and rack shim pack to achieve anything better than a 2000 RPM rated engine.