fj pt6266 loosing boost..no leaks

low boost
low boost

January 2nd, 2015, 11:54 am #1

Recently switched from my 20yo garrett t34 to a precision 6266. It made an exta 60hp on the same boost. Now everthing seemed roses until i noticed boost falling off. It went from running 25psi then started dropping and dropping to a point now it barely makes 5psi..i am no dumby to turbo systems having built over 150 different set ups including steam pipe manifolds intercoolers dump pipes ect. I have ran this same set up for almost 20 years.to date i have removed the exhaust cooler and piping over 7 times to prrasure test and check for leaks.i have changed spring in wg to a 20 psi spring even welded the screamer pipe closed and it still makes no difference.i have sandblasted mymanifold and certain there are no cracks.i have seperated the front and rear housing and turbo looks 100 percent no bent fins or srape marks. Turbo spins freely. Inlet manifold check no leaks..engine and turbo system have no leaks i am 100 percent on this and no blocked pipes..the fj has a stock import head with a forged bottom all the external fruit...done a comp test even over all 4 any ideas anyyonee
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low boost
low boost

January 2nd, 2015, 12:12 pm #2

This has got me puzzeld. Fj runs nice no coffs or spluters.spins to 7grand no misses. Changed fuel pump filters inj serv.new coils leads dynod it to find leak there just isnt one. Someone said valve spings..stock inlets gone soft but ive never had that before had 6 stock fjs prev...wouldnt it fart if the valves were getting pushed open..and would 5psi be enuff to do it..boost dropped 1 to 2psi everyday for 2 weeks..i have heard precisuon turbos can seize the trust washer to the shaft of turbo..i am at the end of my patience
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TeeJay1600
TeeJay1600

January 5th, 2015, 11:03 pm #3

Recently switched from my 20yo garrett t34 to a precision 6266. It made an exta 60hp on the same boost. Now everthing seemed roses until i noticed boost falling off. It went from running 25psi then started dropping and dropping to a point now it barely makes 5psi..i am no dumby to turbo systems having built over 150 different set ups including steam pipe manifolds intercoolers dump pipes ect. I have ran this same set up for almost 20 years.to date i have removed the exhaust cooler and piping over 7 times to prrasure test and check for leaks.i have changed spring in wg to a 20 psi spring even welded the screamer pipe closed and it still makes no difference.i have sandblasted mymanifold and certain there are no cracks.i have seperated the front and rear housing and turbo looks 100 percent no bent fins or srape marks. Turbo spins freely. Inlet manifold check no leaks..engine and turbo system have no leaks i am 100 percent on this and no blocked pipes..the fj has a stock import head with a forged bottom all the external fruit...done a comp test even over all 4 any ideas anyyonee
I found the blanking plates on my Stock plenum weren't up to the task of 25psi and had buckled and warped and this was letting boost escape check them and re make out of 6mm aly or something to make sure.
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Anonymous
Anonymous

January 6th, 2015, 10:36 pm #4

Recently switched from my 20yo garrett t34 to a precision 6266. It made an exta 60hp on the same boost. Now everthing seemed roses until i noticed boost falling off. It went from running 25psi then started dropping and dropping to a point now it barely makes 5psi..i am no dumby to turbo systems having built over 150 different set ups including steam pipe manifolds intercoolers dump pipes ect. I have ran this same set up for almost 20 years.to date i have removed the exhaust cooler and piping over 7 times to prrasure test and check for leaks.i have changed spring in wg to a 20 psi spring even welded the screamer pipe closed and it still makes no difference.i have sandblasted mymanifold and certain there are no cracks.i have seperated the front and rear housing and turbo looks 100 percent no bent fins or srape marks. Turbo spins freely. Inlet manifold check no leaks..engine and turbo system have no leaks i am 100 percent on this and no blocked pipes..the fj has a stock import head with a forged bottom all the external fruit...done a comp test even over all 4 any ideas anyyonee
Definitely look at valve springs, when I started pushing over 30psi head started valve floating, even some decent after market springs were still crap and had to get almost double the standard spring rate, also note that it was only on dyno tunes that we noticed boost creeping down and it boiled down to the valve springs, on the street it seemed fine
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Anonymous
Anonymous

January 15th, 2015, 9:22 am #5

Recently switched from my 20yo garrett t34 to a precision 6266. It made an exta 60hp on the same boost. Now everthing seemed roses until i noticed boost falling off. It went from running 25psi then started dropping and dropping to a point now it barely makes 5psi..i am no dumby to turbo systems having built over 150 different set ups including steam pipe manifolds intercoolers dump pipes ect. I have ran this same set up for almost 20 years.to date i have removed the exhaust cooler and piping over 7 times to prrasure test and check for leaks.i have changed spring in wg to a 20 psi spring even welded the screamer pipe closed and it still makes no difference.i have sandblasted mymanifold and certain there are no cracks.i have seperated the front and rear housing and turbo looks 100 percent no bent fins or srape marks. Turbo spins freely. Inlet manifold check no leaks..engine and turbo system have no leaks i am 100 percent on this and no blocked pipes..the fj has a stock import head with a forged bottom all the external fruit...done a comp test even over all 4 any ideas anyyonee
hi mate
give me a call i have a smoke machine
if you are in sydney
97911388 cheers
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low boost
low boost

February 5th, 2015, 10:16 am #6

Recently switched from my 20yo garrett t34 to a precision 6266. It made an exta 60hp on the same boost. Now everthing seemed roses until i noticed boost falling off. It went from running 25psi then started dropping and dropping to a point now it barely makes 5psi..i am no dumby to turbo systems having built over 150 different set ups including steam pipe manifolds intercoolers dump pipes ect. I have ran this same set up for almost 20 years.to date i have removed the exhaust cooler and piping over 7 times to prrasure test and check for leaks.i have changed spring in wg to a 20 psi spring even welded the screamer pipe closed and it still makes no difference.i have sandblasted mymanifold and certain there are no cracks.i have seperated the front and rear housing and turbo looks 100 percent no bent fins or srape marks. Turbo spins freely. Inlet manifold check no leaks..engine and turbo system have no leaks i am 100 percent on this and no blocked pipes..the fj has a stock import head with a forged bottom all the external fruit...done a comp test even over all 4 any ideas anyyonee
Cheers teejay but i have a custom plenum so no blanking plates. I am down to a meazily 5 psi so tonite fj comes out new clutch needed anyways so it will be off with her head full rebuild with hd valve springs i am hoping to find something i will keep you guys in the know...any fresh ideas welcome..cheers
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low boost
low boost

February 5th, 2015, 1:28 pm #7

Recently switched from my 20yo garrett t34 to a precision 6266. It made an exta 60hp on the same boost. Now everthing seemed roses until i noticed boost falling off. It went from running 25psi then started dropping and dropping to a point now it barely makes 5psi..i am no dumby to turbo systems having built over 150 different set ups including steam pipe manifolds intercoolers dump pipes ect. I have ran this same set up for almost 20 years.to date i have removed the exhaust cooler and piping over 7 times to prrasure test and check for leaks.i have changed spring in wg to a 20 psi spring even welded the screamer pipe closed and it still makes no difference.i have sandblasted mymanifold and certain there are no cracks.i have seperated the front and rear housing and turbo looks 100 percent no bent fins or srape marks. Turbo spins freely. Inlet manifold check no leaks..engine and turbo system have no leaks i am 100 percent on this and no blocked pipes..the fj has a stock import head with a forged bottom all the external fruit...done a comp test even over all 4 any ideas anyyonee
Engine out at my wits end.....aaaaahhhh found the leak..now you can all call me a dumby...a ********..whatever comes to mind..a ten inch long crack in the underside of my plenum....**** i am stupid for asuming. I ******** asumed because idle was sweet there was no leak in the plenum..seems the crack closes under vacume and opens under boost..now to weld the crack ..screw it up to 20psi on the rollers..never asume anything guys..my ******** mistake
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Gareth
Gareth

March 3rd, 2015, 9:40 pm #8

Recently switched from my 20yo garrett t34 to a precision 6266. It made an exta 60hp on the same boost. Now everthing seemed roses until i noticed boost falling off. It went from running 25psi then started dropping and dropping to a point now it barely makes 5psi..i am no dumby to turbo systems having built over 150 different set ups including steam pipe manifolds intercoolers dump pipes ect. I have ran this same set up for almost 20 years.to date i have removed the exhaust cooler and piping over 7 times to prrasure test and check for leaks.i have changed spring in wg to a 20 psi spring even welded the screamer pipe closed and it still makes no difference.i have sandblasted mymanifold and certain there are no cracks.i have seperated the front and rear housing and turbo looks 100 percent no bent fins or srape marks. Turbo spins freely. Inlet manifold check no leaks..engine and turbo system have no leaks i am 100 percent on this and no blocked pipes..the fj has a stock import head with a forged bottom all the external fruit...done a comp test even over all 4 any ideas anyyonee
Although it's a massive pain in the arse.. You found the issue which is great.

Just to throw it out there. I made a pressure tester to check for leaks. Simply get a 4" silicone hose or whatever size your turbo inlet is and put a bank end of PVC pipe in it. I then tapped an air compressor fitting into it and that way you can pressurise the system to whatever you want and listen for leaks. I had a huuuuge leak in my wastegate some years ago. Found it in 2 seconds once I pressurised it.

G
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low boost now big boost
low boost now big boost

March 6th, 2015, 11:44 pm #9

Recently switched from my 20yo garrett t34 to a precision 6266. It made an exta 60hp on the same boost. Now everthing seemed roses until i noticed boost falling off. It went from running 25psi then started dropping and dropping to a point now it barely makes 5psi..i am no dumby to turbo systems having built over 150 different set ups including steam pipe manifolds intercoolers dump pipes ect. I have ran this same set up for almost 20 years.to date i have removed the exhaust cooler and piping over 7 times to prrasure test and check for leaks.i have changed spring in wg to a 20 psi spring even welded the screamer pipe closed and it still makes no difference.i have sandblasted mymanifold and certain there are no cracks.i have seperated the front and rear housing and turbo looks 100 percent no bent fins or srape marks. Turbo spins freely. Inlet manifold check no leaks..engine and turbo system have no leaks i am 100 percent on this and no blocked pipes..the fj has a stock import head with a forged bottom all the external fruit...done a comp test even over all 4 any ideas anyyonee
Put the fj back in with a new clutch. New throttle body and tps.new oil filters and wekded up the crack. Now i got 23psi poppin up on the recall. Its tourching the rears at 130kph on the hyway...better than sex..munched a few gsxr1000 and yamy r1s. 3rd gear and the diff both on there last legs. I got new box and doin r200 after many good years 20 out of my r180. Boost is best see yas at datnats
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Teejay1600
Teejay1600

April 13th, 2015, 6:39 am #10

Recently switched from my 20yo garrett t34 to a precision 6266. It made an exta 60hp on the same boost. Now everthing seemed roses until i noticed boost falling off. It went from running 25psi then started dropping and dropping to a point now it barely makes 5psi..i am no dumby to turbo systems having built over 150 different set ups including steam pipe manifolds intercoolers dump pipes ect. I have ran this same set up for almost 20 years.to date i have removed the exhaust cooler and piping over 7 times to prrasure test and check for leaks.i have changed spring in wg to a 20 psi spring even welded the screamer pipe closed and it still makes no difference.i have sandblasted mymanifold and certain there are no cracks.i have seperated the front and rear housing and turbo looks 100 percent no bent fins or srape marks. Turbo spins freely. Inlet manifold check no leaks..engine and turbo system have no leaks i am 100 percent on this and no blocked pipes..the fj has a stock import head with a forged bottom all the external fruit...done a comp test even over all 4 any ideas anyyonee
I KNEW IT WAS A PLENUM LEAK!!!!!

MY mate had the same issue on his RB30 with custom plenum.

What power you making with that turbo and what's the response like ? Upload your sheet.
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