help with wg problems asap

[chaos02001]

I know this is probably in the wrong forum but I need some help asap. Well the problem I 'am having problems with the wg on my sbrg60-1 internally gatted the problem I'am having is that the wg is leaking at idle. I can feel and hear the wg gases through the o2 dumptube.Is this normal I have sent it back to sbr and mike said there was nothing wrong but I've been told by others that it should not be like that, my big28 was not leaking any help please!

 

[Slowboy]

I had that turbo on my own car for about 10 miles... I tried to make it leak... and it would not. I even loosened the actuator arm the whole way, and finally heard some air by pass. This was because the arm was actually holding the flapper open...

I also tested the WG actuator, and poured fluid into the WG hole with the flapper being held shut ( turbo was sitting on the back side of the turbine housing ) and no fluid leaked from the flapper. I let it sit 24 hours.

If anyone can shed some light, I would be grateful to!

Regards

Mike Huml

 

[Tevenor]

Where is the wastegate actuator plumbed in to?

 

[chaos02001]

well after many hours of tinkering I figured it out the actuator arm is not putting enough pressure on the wg flapper. You can put pressure via a screwdriver or such and the wg seals the wg I can't seem to get it to seal completely so mike is sending me a new arm thanks for the help should be completely fixed in a week or so then i'll post a reveiw .

 

[MGTurbo]

This is an interesting problem and one which i have encountered on a few cars other here. In one application, a Garrett T25 turbo with an internal wastegate is used. After a short amount of mileage the actuator appears to lose its spring tension ( it's base boost setting was 6.3psi) and causes an increase in spool up time, but on full boost otherwise the same amount of psi pressure, but not the actual volume of air, This causes a bhp drop.

One of my own cars had this problem so bad that the wastegate valve could be heard to rattle loudly at idle.This causes a bhp drop. Another very common problem is a cracked housing and i see it on every T25 i inspect, regardless of mileage. Seems to be very common on smaller turbos and i think the only way out is an external wastegate.

Just thought this info would be of some use, apoloigies if its already been mentioned before, but it does apply to DSM's as one of my friends here has an Eclipse and encountred this problem.

Gareth

 

[kpt4321]

Originally posted by MGTurbo
but on full boost otherwise the same amount of psi pressure, but not the actual volume of air, This causes a bhp drop.

Can you expand upon this theory of having the same boost, but less volume flow? I would be interested to hear your reasoning behind it.

 

[MGTurbo]

Sure. Bigger turbo running same boost produces more bhp than a smaller turbo due to? My figuring being it must be producing more volume of air. Slight change of subject, i've also seen the difference on a rolling road where one guy was running 11psi with a loose wastegate then 11psi with a tight one and he gained 40bhp... i have the printout's to prove. Of course, it could just be the lowering in intake temperatures that would cause the difference in power figures between a bigger turbo running same boost as a smaller turbo. Thats all theory of course and in my head, if you could explain to me futher and expand my knowledge that would be appreciated.

Gareth