definitely... will be sure tomorrow eve.

hey everybody, finally found someone to help me out welding my IC piping to eliminate all the couplers I had (and the ones that were leaking)

Lagos: I have come to the conclusion that the gauge is working properly after i inspected all connections and lines leading to it.

Unfortunately elimiating 5 couplers by welding didnt do the trick (though i was able to get to at least 2inches of vacuum now instead of 6 which definitely leads me to believe my turbo has taken a Shat. I suppose internal seals failed. I dead headed the turbo and placed a gauge on the outlet. when i gave it gas it only made about 4psi at 5k rpm. I understand the motor should be under load but the turbo should be performing better than that.

I will be replacing it and putting on another CT20b this weekend hopefully.


will let you all know what happens!




This post has been edited by easternpiro1: Jan 23, 2013 - 10:57 PM

.

This post has been edited by easternpiro1: Jan 28, 2013 - 10:34 PM

before switching the turbos I decided to test the turbo by "dead heading" it and inserting a pressure gauge measuring in PSI. some say the turbo needs to have load on it however even standing still should it not be blowing out more pressure?

turbo test

where is your boost gauge connected to? at idle you should be getting 18-20 inHG not 2 to 6.

>


Matt, the thing about this test is that there is no load on the engine. You are really not supposed to be able to build any boost this way. I bet I would get exactly the same results if I did this on my car and my turbo works fine.

Lagos is right on this one. The test you've done is useless. At free-revving, there isn't enough exhaust air flow to drive the turbine at a high enough RPM to build boost on the compressor side. Also, a turbo isn't a positive displacement pump. Unlike a roots supercharger where there is always the same volume of air forced into the supercharger, it's not because a compressor is doing a revolution that a certain amount of air will be force into the compressor outlet. It takes a lot of turbo RPM to build boost o the compressor outlet side.

I can't beleive you have not ruled out this problem yet. I'm not saying that you didn't try hard enough, you certainly did. But I'm sure you missed something really basic. A turbocharger isn't something that is really complicated. I suggest you to go back to the base. Do a boost pressure test from the turbo compressor. Be sure to block off the IAC inlet. Verify that you can get at least 30 PSI in this test.

The other test is to verify that the wastegate stay shut and that all the exhaust airflow actually pass through the turbine.

Then, physically verify that turning the turbine result into a compressor revolution and make sure that the shaft is turning freely. Verify that the turbine wheel is in OK shape (no bent/broken blades).

If all those points are ruled out, there is no physical reason for this turbo to not boost.

Are you sure your boost gauge is accurate and correctly connected to the intake manifold. It should read about -19 inHG at idle, 0 psi when the engine is off. Verify if it is correctly displaying a boost event using a mityvac or compressed air (be sure to use a pressure regulator and set it at around 25 PSI).

Do not give up!

Sam

>

I figured as much and i knew better! lol did it anyway to make sure. I remember when sitting still on my previous swap, i could rev the engine and there would be Blow off. It no longer does it.


>
thanks for the vote of confidence sam! I have done almost everything at least twice.

I will do another boost pressure test as last time I didnt run it THROUGH the turbo compressor I took the piping off of the turbo and pressurized from beginning of piping to end. (I was told I would ruin the turbo if too much PSI was put through it)

I took the turbo off (even separating it from the manifold) and spun it while inspecting all areas smoothly without touching the housing. all looks good on the fins as well

boost gauge reads 0 when car is off however when at idle it fluctuates from -14HG to -16 and has gotten as low as -12 at times.

as far as the IAC is concerned, I do notice that the car will idle strangely (drop in RPM from 1000 to 800, and at times feels like it wants to cut off) After fixing a hole in the hose nest to the IAC there is still some trouble, but I will clean the IAC with brake cleaner to be sure.

Im fairly certain that the WG is closed and that the flapper is ok as I have placed the car on a dyno without downpipe to inspect it and hold it closed

wastegate/dyno


again thanks for all your help guys! I will keep trying!

This post has been edited by easternpiro1: Feb 15, 2013 - 7:14 PM

guys its not measured in negative numbers. its measured in inches of mercury which is considered a vacuum. if you made it negative then its considered boost. make sense?

now 14 to 16 is pretty low and 12 is really low. have you done a compression test?

>

I havent done one since the problem started, its not often on 12 but consistently 15-16

>


Thats way too low. Do a compression test next.
Where is the boost gauge taking its vac from?

>

the gauge is Tee'd into the line coming from the BOV to the intake manifold.

Hi everyone Myself and Ben (bsamps) and Sam all took a look at the car this past weekend.

could not find the cause of leak but there is some concern that I may have a bad head gasket.

We did a compression test on the car and it initaly read from cylnder 150 150 135 152 (from cylinder 1-4)

after testing it again (immediately after a drive) it read 160 150 140 150. Im not sure of the compression stats for this motor but it seems consistent with the exception of cylinder 3.


also fond that my exhaust manifold wasnt flush with the head and tightened it. after It was re tightened the oil dispstick would not stay in and kept spitting out oil. (even after numerous attempts to adjust it) Suspicion is that this is a motor problem....

Turbo does seem to be putting out pressure, no leaks from the turbo or any abnormal signs of wear. Both inducer and exducer are intact and operating properly. Turbo is not burning oil at this time. Did notice that blow off valve is opening to let off any excess charge in the intake pipe, but is not making any noise due to the fact that the car is not making boost.
vacuum reading at full throttle is only reading at -4 inhg. Like Matt said the exhaust manifold was not torqued down and was leaking. After that was repaired the dip stick would not stay in the base of the motor and was pushing oil out at a high rate. Found a large oil leak on the back of the motor near the power steering pump (unsure of the origin). Found that the PCV valve is operating properly. Tested cooling system by bleeding water through the system. System would not bleed all air out of system and continued to push air through the upper funnel when squeezing the upper radiator hose. Engine shakes at idle and doesn't seem to put out as much power as it should even without boost when driving.
Checked vacuum lines and boost boost couplers. Found no leaks. Vacuum remains at -17 on inital start up at idle. Engine leans out occasionally and runs extremely rich occasionally without any changes in fuel pressure.

has anyone checked mechanical timing on this motor?

pushing oil out the dipstick, and the air in the rad both sound to me like symtoms of a blown headgasket. can you test the coolant for oil? (the little test kits they sell @ like autozone and stuff)
between that and the comp test, i'd guess either the HG is bad, or you have cracked ringlands.

or the crankcase ventilation is plugged up

I'm gonna start tearing it down here in the next few days to find the culprit.

Haven't checked mechanical timing yet, but I will before I take the head off to have a look-see. Hopefully it's not a cracked ring-land. Not developing any smoke out of the tailpipe so this seems a bit weird...

Yea usually if a ringland is cracked you burn oil, not leak the hell out of it. Haha. Take the valve cover off and rev it up to see if you can hear/feel/see a surge of air/oil?

>

or not done correctly...could be

sounds like HG could be very likely.

*Fixed*

Observe...

http://www.youtube.com/watch?v=9cD_i1ihG6g...eature=youtu.be

This post has been edited by bsamps4: May 10, 2013 - 5:47 PM

BOOYAH!

Went from negative boost to too much boost!

Less time on the internet + more time under the hood = fixed car.

What on earth was the problem?

Big plastic bag lodged in intercooler.

...

Well then, consider me bamboozled.

>


Are you serious? WTF?

>

this thread was like reading a suspense novel and this is the climax!?!?!?

Glad its fixed but the culprit issue made me laugh

This post has been edited by Island_Racer: May 11, 2013 - 5:01 PM

>
YOURE BAMBOOZLED?!? im absolutely flabbergasted and befuddled!

>
YUP! all those times ive taken that piping off, inspected it and put water in the damn intercooler to check for leaks... i dont understand HOW IN THE WORLD that bag was in there all this time. it makes NO SENSE!


>

I thought ben was joking!! i was like ben..... TELL ME it wasnt in plain sight.... Ben: YUP! well ill be damned.... IT MUST HAVE beenlodged in the upper part of the end tanks because i looked in each end of them before putting water in there last summer or whenever it was I did that test.



SIGH... anywho the car runs like a MONSTER.... gotta fix a few small hiccups and ill be focusing on paint next!

...wut.



Matt, wouldn't you have felt pissed if you'd sold the car and the new owner found and posted that the culprit was a plastic bag?!

Either way, good job Team Raleigh for being NC's boost headquarters. Now, anybody up for a V6 swap?

This post has been edited by Keiri: May 12, 2013 - 9:43 PM