Can't find boost leak!

[hpcbmw]

Getting my new to me 2000 f250 w/ 145k miles on 7.3 on the road. The truck is bone stock. I found a rip in an intercooler boot and replaced that, and sealed up a couple other small intercooler line leaks. I could then hear the turbo kicking in and feel more power. That lasted for a couple days, then it seemed to be losing power again.

I made a boost leak detector that fits in the intake tube in place of the large plastic connetor (1/2 between the airbox and the turbo). I left the little green pressure hose in place and put a plug on the pcv hose from the valve cover.

I pressure up to 10-15 psi and can definately hear a leak - I'm pretty sure it's on the passenger side, back by the turbo somewhere. I spent over an hour with a soap spray bottle, climbing all over the engine and can't track down the leak. I sprayed and felt around the downpipes - no black soot and no air leaking out. I checked all the intercooler boots again and again - they don't seem to be leaking. The turbo wheel spun freely and didn't seem to be damaged or have any excessive play.

Any ideas of where else to look? Should I be plugging intercooler pipes or something, to stop the air pressure from going into the engine via the valves, to really get a good pressure check? If so, how/where would I accomplish this.

Thanks for the input!

[labonte.r]

I dunno if you looked but when I went to clean up my intercooler piping i found that the pipe was rubbing on line of of the power steering pump. I actually caught it right before it put a hole straight through. I have seen that a few other people have had this problem too. Maybe somewhere to look.

[dieseldan2005]

My boots on the turbo spider would also slide down. Those are the orange boots below the turbo. Maybe you already checked those, but the clamps one mine would get a little oily and then slide down allowing boost to escape around the clamp. Just a thought.

[balistic]

I would take off the boot and pipe on the down stream side(passenger side) of the intercooler, plug the intercooler outlet off then pressure it up or all your air will go into the engine. Then listen around the intercooler see if it has some cracks in it. A 5.00$ stethoscope might be a good investment

[Fred Swanson]

Originally Posted by balistic

I would take off the boot and pipe on the down stream side(passenger side) of the intercooler, plug the intercooler outlet off then pressure it up or all your air will go into the engine. Then listen around the intercooler see if it has some cracks in it. A 5.00$ stethoscope might be a good investment

The system should hold pressure for awhile if it's sealed correct?

[balistic]

only if your rings and valves have a perfect seal.........on an engine with some miles on it thats pretty unlikely, but could point its probably sealed enough if you keep air to it

[Fred Swanson]

Originally Posted by balistic

only if your rings and valves have a perfect seal.........on an engine with some miles on it thats pretty unlikely, but could point its probably sealed enough if you keep air to it

Got it, Thanks

[alshayne]

I wasn't getting the pressure i thought i should and just by chance, when i took off my intercooler pipe to do the "foil delete" mod there was the culprit to my problems! My powersteering pump had rubbed a hole in my intercooler tube.
My question is, where can I find a tube?
If i have the hole welded up will it affect anything?

[Highwaywrench]

if you can find someone who will clean it properly, before and after welding it, you will have no problems at all. Been there, done that.