low turbo boost (was high)

[460429_freak]

before I could boost up to 7 maybe 8 (I know not real high)but now if I stand on it it will barley do 3? so I cleaned the cdr checked the turbo will turn no end shaft play cleaned breather.. still the best is 4... but noticed a exhuast leak so I crawled under the truck the exhuast pipe on the passangers side is crack and leaking (which turns into the turbo) could this be my boost problem ?????

87 6.9 hypermax turbo

 

[icanfixall]

It probably is. Have it repaired and test again.

 

[hesutton]

Most likely it is. That lost exhaust pressure and volume will decrease the turbine speed and decrease your boost.

Heath

 

[tractorman86]

Most likely it is. That lost exhaust pressure and volume will decrease the turbine speed and decrease your boost.

Heath

precisley

 

[460429_freak]

thats what I was thinking it's cracked where they can weld it on the truck... you can step on it now nothing but black smoke and no go where before slight smoke and alot of go go go

 

[Diesel JD]

Is this the up pipe or one of the crossover pipes? If its the up pipe its probably not a bad idea to try welding it before replacing cause that stuff gets epensive, if its one of the crossovers a good shop should be able to make you a new crossover pipe pretty cheap.

 

[Dsl_Dog_Treat]

Most likely it is. That lost exhaust pressure and volume will decrease the turbine speed and decrease your boost.

Heath

And it doesn't take much of a leak to loose that good boost either.

 

[suv7734]

Is this the up pipe or one of the crossover pipes? If its the up pipe its probably not a bad idea to try welding it before replacing ...

Just a word of caution, usually pipes that are old, thin and rusty will get holes in them. If you are going to have it welded make sure the welder is very competent at his job. If there is anything that gets left in the pipe after welding that is small enough to get blown around by the exhaust gas @ 3,000 RPM guess where it goes... right through the turbo.

 

[Diesel JD]

Good point, if its cast iron its also going to require somebody who's a really excellent welder. You could probably get a new pipe from hypermax but it could be pricey.

 

[460429_freak]

no hole just a crack that you can move the pipe and make it wider (hence the truck is parked) I am worried about the thin pipe though... I think the vibration of the old wore out motor just finally mad it crack... if it to bad the ol motor is wore out It'll give me a reason to put the new motor in and rebuild turbo...

 

[tractorman86]

Just a word of caution, usually pipes that are old, thin and rusty will get holes in them. If you are going to have it welded make sure the welder is very competent at his job. If there is anything that gets left in the pipe after welding that is small enough to get blown around by the exhaust gas @ 3,000 RPM guess where it goes... right through the turbo.

very good point here!!! take it off to be welded just for good measure!