I am still trying to diagnose a no boost issue on my turbo'd 2.5L Jeep Wrangler. I put a new turbo in it and there is still zero boost. Well, maybe 1 psi if I really rev it up. I used some tubing as a stethascope and found a few fairly small exhaust leaks in the piping going from the exhaust manifold to the turbo. They are loud enough to hear without the tubing, but it helped my pinpoint where the leaks are actually coming from.

So I guess I am wondering if a few exhaust leaks will keep the turbo from building boost.

Thanks!

 

post some pics of where the leaks are and some more details on the setup. What are you using as a turbo filter? Some people use rags and crazy ---- like that and they get little to no boost. If you can get to the leaks with a welder, definitely fix them. If they are more than a tiny pinhole I would say to take care of it asap to get some boost

 

Are you trying to build boost in neutral?

 

lol good point

 

Ha. I am not trying to build boost in neutral. I have about 4 feet of pipe from my manifold to the turbo, with about 5 joints clamped together. The cheap crap parts store pipe is so thin it leaks kinda bad. The pipe ovals very easy when you clamp it. I picked up a MIG welder so i'll weld the pipes up and see what happens.

 

I took the 5 bolt exhaust flange off and noticed that the hole in the turbo housing that the wastegate covers was welded over at one point, and is not letting the gate close properly.

Any pointers on where to get a T3 exhaust housing, 5 bolt-internally gated, .63 a/r?


Also, what would happen if you put a T3 cartridge that came from a turbo with a .48 a/r ratio into an exhaust housing with a .63 or vise versa?

Thanks again,
Rob

 

Get a 5 bolt and drill a hole in the flange for the waste gate to open, and then weild a small pipe to it and run a open dump tube or tie it back into the exhaust.


I belive the whees are the same size just a differant ar. exhaust for each one- .48 or .63
I took a volvo 48 and put it on my thunderbird turbo that had a.63 exhaust housing for a quicker spool.

 

i think he means that someone welded a crack in the housing and the weld wont let the flapper shut all the way. post some pics, maybe you can just grind it down without too much work

 

I had a friend footbrake it and try to build some boost so I could check for leaks. While it was fairly cool, I soaped the inlet flange and it made a few small bubbles, but there were no audible exhaust leaks. I have already replaced the turbo (kept the old exhaust housing), welded up the hot piping, and checked the charge piping. The only thing I can guess is a problem with the flapper not closing all the way.
I'll have to take it back apart tomorrow and take some pics. It was definitely welded up already. The surface is not completely flat, and there is a small piece missing from the hole. It looked to me that the flapper would cover it up though. Maybe I can weld it up and grind it flat again.
If I have someone footbrake it again, I should be able to remove the discharge piping and feel significant air flow from the turbo? I just have no idea why it is not making boost.

 

I think I may have found an easy problem to fix. I had the wastegate actuator arm a little loose in my opinion. I put a little tension on it. I took off the discharge piping, started it up and cracked the throttle. A crapload more air came out than before. I have yet to test drive it though. I bought a cheap Ebay oil feed flange and it cracked for no apparent reason. I'll test drive it when it is no longer leaking oil all over the hot cartridge.

Thanks all.