noisy 38r

[nasty6.6]

Hey everyone I bought a 2000 f350 with a 38r on it but looks like it has a stock wastegate spring and stock plastic intake horn. The truck only builds 5lbs of boost and it sounds like it has a huge boost leak. Running down the highway I can not talk on the phone and the radio has to be almost all the way up to hear it. Also while running 70 and going to pass the truck will not go even if I kick it down to 4th to pass. I took the edge off to see what difference it would make and now its a turtle.

I did a pressure test on the intercooler and it holds 15 lbs for over a minute and then it slowly bleeds off but I think its going through the valves/exhaust

Truck has 230k very little blow by and gets on average 14-15 mpg on the highway its just loud, not turbo whistle but turbine moan sounds like a turbine spooling. Sounds cool if you are riding around with your buddys but wont beat a prius... Any help would be appreciated.

 

[nasty6.6]

http://www.facebook.com/justin.alley.9461?ref=tn_tnmn

Here is a video of the truck and the rpms only get to about 2200 or so.:shocked:

 

[bad12jr]

Post the video on YouTube. Facebook links never work. What plastic intake horn are you talking about. Never seen anything plastic on a 7.3 other then the intake tube going to the rubber boot.

Sent from my x2 somewhere

 

[nasty6.6]

ok ill post it on youtube in a few. Its the stock rubber boot going to the turbo not plastic.

 

[BigAlsPSD]

Sure it's an R not just a GTP38, the stocker?

 

[nasty6.6]

ok fill me in please what is the difference? and it has a rod with a spring as a wastegate looks like it is manually adjusted.

 

[nasty6.6]

I think its a 38r bc the intake housing is bigger and has the ported areas around the wheel like an r where the 38 looks like a stock refurb.

 

[TARM]

First its rarely the actual IC that is leaking. Usually its a boot on the IC or the boots on the Y. You need to pressure test the whole boost side. Put the tester on the Turbo intake. If you have the CCV going into the intake disconnect it and plug that hole. Leave the CCV to atmosphere for the test. When its only making 5 psi and you are throttling up are you getting a ton of black smoke as well>

What are your egts looking like?

It could be the WG is opening up but this many times is a split boot that looks fine until it gets some pressure then a 2" long slit opens up and blows it all out.

If its a WG you can try taking the red line off and plug it. Also wire the WG actuator arm so its held firmly shut with a piece of wire and twist it tight. That will rule out the WG being the issue.


As AL asked are you sure you have a GT38R ball bearing turbo and not a GTP38 Journal bearing turbo. Did you get it second hand or from a vendor shop.

Make sure the up pipes are not leaking. Look for any soot around the collector along with any looseness. I thought mine were fine as I have very clean tunes so next to no soot. It looked great from the front. When I went to swap to a T4 turbo the up pipes literally fell off. The collector just lifted off of them.

 

[Justin@DP-Tuner]

ok fill me in please what is the difference? and it has a rod with a spring as a wastegate looks like it is manually adjusted.

GTP38... http://inlinethumb29.webshots.com/37852/2709566090103269483S600x600Q85.jpg

GTP38R... http://cf.mp-cdn.net/b3/32/e92b78e89211c023f247f2617663.jpg

The manual wastegate is just an aftermarket option for the stock turbo(GTP38).

 

[BigAlsPSD]

They both will have a similar designed wastegate. The 38R is a drop in replacement for the stock GTP38 but is Ball Bearing rather than the stocker being journal bearing. Compressor wheel is 88mm versus a 80mm and the turbine housing is 1.00 A/R versus a .84 A/R.

Either way it sounds like you have boost or drive leaks.

When you said you pressurized the intercooler, was it just the IC itself or the entire system by pressurizing at the intake boot to the turbo? Have you checked for soot around the up pipe connections?

What is your fuel pressure? Any in tank modifications to remove the screens for the mixing chamber?

 

[nasty6.6]

its a 38R with the factory manual adjusting wastegate. The guy I bought the truck from got the turbo from a kid that needed cash so it was used when he got it.

I put the pressure regulator on were the air filter went and pressured the entire system. Held 15lbs so im ruling the boots out if its a leak its a pinhole. The boost gauge works and it only shows 5lbs at ful throttle under the trucks power but shows 15 with the system presured up with the tester.

The truck has a hutch mod in tank, fuel bowl delete and has a filter/h20 seperator on the frame inline. The turbo has very little shaft play and wheel looks great no nicks or anything.

 

[nasty6.6]

what should that waste gate look like when properly adjusted? The previous owner had it tightened up so the spring had no play at all and was fully compressed.

no black smoke at all under throttle and it has a new fuel filter as well. With an edge program on it, it would smoke a bunch but wiht stock tune no smoke.

IDK on egts the gauge is inop hadnt fixed that part yet, the truck has had lots of little issues so gauges are the last of the worries. The truck came out of ben wheeler tx and it supposedly had new hubs new clutch and all these new parts and it doesnt look like anything he said that was done, was actually done.

 

[TRUBBS]

Compressor wheel is 88mm versus a 80mm and the turbine housing is 1.00 A/R versus a .84 A/R.

?

88mm comp wheel?

 

[nasty6.6]

88mm is a huge wheel for a stock dropin on a stock pedistool idk on that but it does look like the 38r pic posted previously.

 

[BigAlsPSD]

88mm comp wheel?

Oops, meant turbine.

Comp is 66mm vs 62mm

 

[BigAlsPSD]

Exducer size is 88mm the measurement still on the compressor wheel, just not the inducer as many are rated, Garrett's advertising got me questioning it.

 

[TARM]

Just an FYI for those that do not know: the reason turbo comp wheels are rated by the inducer is that is the part of the wheel that takes the "bite" out of the air column. Its what dictates the ultimate flow rate of the wheel. The Exducer is what throws the now compressed air out of the turbo and on to the engine.

The part to first contact the air column is always the inducer. So on the comp is the smaller inner section but on the turbine its the larger outer diameter as that is what touches the exhaust gases first as it enters from the opposite side of the wheel compared to the compressor.

 

[chris89]

You said you just pressure tested the cooler, do the whole system. Maybe you said you did and I missed that part, but if the boots on the "y" are loose they wont blow off, they will just leak the air off. Have you checked your air filter. I'm supprised no-one has told you to take the edge off yet becuase they suck.

 

[AirFishAutomotive]

You said you just pressure tested the cooler, do the whole system. Maybe you said you did and I missed that part, but if the boots on the "y" are loose they wont blow off, they will just leak the air off. Have you checked your air filter. I'm supprised no-one has told you to take the edge off yet becuase they suck.

because it doesnt seem to be causing the problem , i would say a loose boot somewhere, and did the egt question ever get answered ?

 

[nasty6.6]

I pressured the entire system and held 15 psi. When under engine power I only build 5psi and no more at all, gauge works bc it showed 15 psi just as the regulator did when I pressured the entire system.

The egt gauge is inop so I have no clue on egts. Im going to pull the down pipe off this morning and check the exhaust wheel. Edge is no longer on the truck back to stock tune.