I am having a hard time understanding this. But pull of boot off the intake horn. And plug it with a plumbing cap. Then pull the boot off the turbo and get another plug cap and thread an air fitting into it. Hook up air through a regulator and give it 40 psi. Listen for leaks. This will test the entire air system from turbo to u take. Eliminate that. If that’s what you did then ok.Are there any, any other places intake air can leak after the intake plenum? When I plug it up to air on the turbo, it loses air and I can hear it but it sounds more like the back driver side of the engine. Is that the normal place where the air would go out?
Yep I tested it both ways like you mentioned. Only gave it 20 psi air though.I am having a hard time understanding this. But pull of boot off the intake horn. And plug it with a plumbing cap. Then pull the boot off the turbo and get another plug cap and thread an air fitting into it. Hook up air through a regulator and give it 40 psi. Listen for leaks. This will test the entire air system from turbo to u take. Eliminate that. If that’s what you did then ok.
Next hook up the intake side and feed it air. Listen around the intake shelf to see if any gasket there is leaking. If not then I’d say your turbo has something wrong with it. When you push air into the intake you might have some leave the crankcase vent. Depending what valves are open.
I just tried turning one side while holding the other, they’re connected :/. So no problems thereLeft field time, pull both the exhaust and intakes , hold the compressor wheel and try to turn the turbine wheel.
If you have access to another turbo I would try that.
Yeah cause the gauge goes up when I plug it to shop air. And the truck id performing badly. Thanks for the info on the pin, guess it’s not that.If the diaphragm does not go down you will not have fuel for more than about 10 PSI, You can get around 10 PSI boost with a THD pin turned to the backside and therefore no extra fuel. Tried it once to see what would happen. Are you sure your boost gauge is good?
Hey Gumby thanks for the post. Yes it has the very minimal side to side play in the shaft. So I just swapped in an HX35W with the 12cm exhaust housing.... still no boost. . That sucks. I have gone over the afc housing diaphragm to look for leaks, as well as the reference line to the AFC. When I open the oil fill tube while it’s running it just barely vibrates and moves. At this point it must be somethin wrong with the engine, I feel like I’ve gone over everything. At idle it has no boost so not 1 psi like you mentioned. So I guess that rules out the trans. This suxYes it should be spinning if the motor is running. My hx 35/qsv was almost at 1 psi at idle(73°EGT worth of throttle was 1psi no load) with a nice whistle from both ends. At all times.
You hear the turbo whistling as its spools, that means it's doing some work and the gauge is not registering it, nor is your engine responding to the additional air(that may or may not be getting to the motor or gage ). Try pulling the boot at the intake horn, verify flow changes with motor rpm.( be careful no resistance on the compressor means it can overspeed if you rev too high)
Oil leak ... is it coming from the pump it self insted of the gasket, oil or is it fuel ?
Air out the draft tube
Yes the piston rings are susposed to pass air on a leak down /boost leak test see ring gap. The question is is it excessive? Do the "Cummins blow-by test" to investigate further. Most don't like the blow by test because it does not identify the source of trouble just a presence of it . You should normally also have air coming out the exhaust as normally at least 1 pair of valves are in overlap.
Radial Shaft play...
None =locked up /damaged bushings
It should move side to side a few thou, there is a +/- spec, so long as there no housing contact is typically considered a pass. Look for shiny patches on the housing where the intake wheel may have made contact.( shiny patches don't equal non-functional that hx35 experienced a paper towel going through it, it was missed when finnishing the Allison install, damage was done but it survived 30k mi, had two shiny patches devlop over time(14mo) in the intake housing from contact. all the blades showed minor contact damage it needs a CHAR for repair still made 28psi on stock fuel )
Thrust( in and out ) should be tight, almost 0 There is a spec for what shoule be there.
Temp turbo swap..
Sounds like it would rule out the turbo as the failure.
Still a possibility?
Problems not ruled out
By pass achieves the same result ic pluged , remove hapymeal toy(or what everis plugging the ic)... 5psi is record boost for the truck come sounds like it's been working on plugging up for a long time.Now pull the boost tube ( carefullying) dose it spool ? Yes, pluged down streem remove happy meal toy from intercooler. No, turbo $hit the bed.