Volvo 740 Turbo with "shaved" housing with a hole in it ?
circuit slave
Well, it turns out that the 2" aluminum foil-type hose which goes from
under the airbox to the back down by the exhaust I assume was very old
and had holes. I replaced it and have boost but the problem I noticed
is the Turbo housing was shaved with some type of tool and a hole was
made?
To relieve pressure? Why would they have done that? I mean maybe
that's why I dont' have full boost turbo power and maybe why the guage
is somewhere around 10 o'clock when I'm not even moving?
I was going to plug it with JB Weld, but now I'm afraid. I mean I
don't want to blow up the thing. Do you think the previous owner had a
pressure problem so they did the mickey mouse job and relieved the
pressure by shaving the metal housing and alowing a hole for pressure
relief?
Any suggestions are appreciated. Thanks !
James Sweet
> Hi everyone I started another thread in which I lost turbo pressure.
> Well, it turns out that the 2" aluminum foil-type hose which goes from
> under the airbox to the back down by the exhaust I assume was very old
> and had holes. I replaced it and have boost but the problem I noticed
> is the Turbo housing was shaved with some type of tool and a hole was
> made?
>
Can you get a picture? I can't think of any hole that should be in the
turbo housing, where exactly is it?
> To relieve pressure? Why would they have done that? I mean maybe
> that's why I dont' have full boost turbo power and maybe why the guage
> is somewhere around 10 o'clock when I'm not even moving?
>
As I said earlier, the guage is supposed to sit around 10 o'clock when
the car is not running. Black is vacuum, yellow is boost, the place
where they meet is atmospheric pressure, if the guage is not pointed
there when the engine is off then it's broken.
> I was going to plug it with JB Weld, but now I'm afraid. I mean I
> don't want to blow up the thing. Do you think the previous owner had a
> pressure problem so they did the mickey mouse job and relieved the
> pressure by shaving the metal housing and alowing a hole for pressure
> relief?
Did something wear on it and make a hole? Or is it on the exhaust side?
Perhaps the car ran lean and overheated the exhaust housing, melting a
hole in it.
circuit slave
metal down on one the left side) and a whole was created. I believe
its a Garrett (it's got a metal little label that's all greasy)
So maybe that's why I've had the leak all this time? But the hose I
replaced helped. I mean I accelerate and such.
Now by "exhaust side you mean after the intercooler and AMM, right?
Because I mean the ACTUAL TURBOCHARGER housing, if that makes sense.
circuit slave
housing" of the turbo charger and shaved down one side. It looks
really weird. I can email you the pics.
Peter K L Milnes
with EGR (the hole being on the manifold just above the turbo mount, should
have a metal tube going to the EGR valve) that caused the PO a problem so he
removed it.
All the best, Peter.
700/900/90 Register Keeper,
Volvo Owners Club (UK).
"circuit slave" <sh...@earthling.net> wrote in message
news:1140310069.6...@g44g2000cwa.googlegroups.com...
James Sweet
Yikes, that's definitely a problem. By exhaust side, I mean the exhaust
turbine housing, as opposed to the compressor housing. The former is
cast iron and will be all rusty, the latter is aluminum and facing the
front of the car.
Are your engine mounts completely shot? Only thing I can think of is
maybe the turbo has been rubbing against something but I've never seen
that happen.
You can see a good picture here of a T3
http://www.servia.fi/~professi/AdvHTML_Upload/files/timon_tiomi_012.jpg
As well as another showing the inside, with the compressor and turbine
blade assemblies joined to the shaft running through the center
cartridge. The wastegate actuator is also visible.
James Sweet
> I think you will find that James may be querying whether your car was fitted
> with EGR (the hole being on the manifold just above the turbo mount, should
> have a metal tube going to the EGR valve) that caused the PO a problem so he
> removed it.
>
>
I've never encountered a Volvo with EGR, I don't believe they used it in
the US market. None of the manifolds I've ever seen have had any unused
holes in them. The tube I'm referring to is a corrugated aluminum hose
which connects a sheath over the exhaust manifold to the airbox, the
purpose being to draw heated air into the intake when the engine is cold
to accelerate warmup. There's a wax thermostat in the airbox which
operates a flap valve to close off this tube, if it gets stuck open and
hot air is drawn in once the engine has already warmed up then the air
mass meter can be damaged.
circuit slave
flap that flaps open/closed. I accidentally "touched it" (because the
car is so old and never maintained, touching can damage :P) and part of
the flap crumbled. Where is the thermostat in there?
Looking at that pic---I don't know which side is which, hehe. But Okay,
well, interested, here are the pics !
http://i29.photobucket.com/albums/c300/circuitslave/56bfbefc.jpg
http://i29.photobucket.com/albums/c300/circuitslave/17edccea.jpg
http://i29.photobucket.com/albums/c300/circuitslave/KIF_0569.jpg
circuit slave
James Sweet
> I see, well, the whole is on the compressor side, as you can see.
>
Crap! That's sure the first time I've ever seen THAT happen! That's a
Mitsubishi turbo, same one I have in my '87. It's pretty clear that the
aluminum hose has ground a hole in the compressor housing from years of
rubbing, it's no wonder you're losing boost and getting funny sounds.
Try patching it up with some JB Weld, just don't get chunks inside the
turbo. A better solution, if you're able to do this, is to remove the
housing and take it to a welding shop and have them TIG the hole closed
but removing it with the turbo on the car is a real pain, there's not
much wrench access.
circuit slave
happened with rubbing.
I'm looking into it---FYI, the Volvo was a single owner--my uncle and
it's been like that for years. And his son (who let's just say is had a
somewhat drifty life) told him "Dad, I know a guy who fix turbo
charger's for like $75."
It's steel, no way that could have happened, IMHO.
zenc...@comcast.net
I think not.
circuit slave
car --everything looks fine no obvious signs. I don't know, not to
jump to conclusions, but it just looks devious.
circuit slave
maybe?
I replaced the pre heat house, as you can see in the pic, but the hole
was blocked by the old house, that's why it makes me suspicous.
James Sweet
It's aluminum, and it's definitely a hole rubbed in it, look at how it
lines up there, I'd bet money that's what happened. I have the exact
same car with the exact same turbo, there's no hole there and absolutely
no reason to have one. Aluminum is soft, my alternator has a gouge
rubbed in it from the plastic cable sheath rubbing on it over the years,
even steel will wear like that if a bit of oily road grit gets in there,
it's the same way you can polish scratches out of metal or glass with a
cotton cloth and some abrasive powder.
James Sweet
> Would JB Weld hold up to the heat generated by a Turbo at full boil?
>
> I think not.
>
Not on the exhaust side certainly, but on the intake it might, it'd be
iffy though. Best solution aside from replacing the housing would be to
weld it.
circuit slave
couldn't JB weld work?
I talked to my other uncle who says, well, it's not like it's on the
exhaust side, so it might work.
I'd get it welded but--well, It's my daily driver and if it's from
wear, it's been like that for years, so a month or two isn't going to
make a difference I think.
circuit slave
thought I lost power, but I never really had it to begin with, hehe.
James Sweet
Well patch it with something, with a boost leak like that you're burning
a lot of extra fuel since it's metering the air before the leak and
fueling accordingly. You'll burn up your catalytic converter driving it
like it is.
Michael Pardee
news:1140378091....@g43g2000cwa.googlegroups.com...
> Would JB Weld hold up to the heat generated by a Turbo at full boil?
>
> I think not.
>
doubt the compressor side gets much above 300F and the pressure is
insignificant.
The way I'd do it is to clean the surface with brake cleaner and JB Weld a
piece of metal over it - I'm concerned the JB Weld might crack if you try to
bridge the void with it. A coin that is slightly larger than the hole will
conform to the curved surface reasonably well. JB Kwik or a small bead of
the putty equivalent will hold the plug in place without the need to come up
with a fancy clamp; you'll just need some patience to hold it until it
sets - about five minutes. Then mix some JB Weld to apply around and over
the plug. Epoxies harden best when hot, so the car should be drivable within
an hour or so if you don't wind it up too much.
BTW, I would expect noticably better performance and fuel economy from
repairing the hole. It is having the same effect that any other hole in the
boosted side of the intake has: it draws more air through the AMM than the
engine is really using, which convinces the ECU to inject fuel to match. I
don't know how it got this way, but you'll be a lot happier when it is
fixed.
Mike
circuit slave
covering the whole somewhat.
So, if this is what happened---isn't this rare? I've yet to hear
about something like this.
I don't know---it doesn't seem right.
circuit slave
but that repair sounds more sufficient. I have JB-Weld --so your
saying like buy the stick or the Kwik just just get it covered because
the regular Weld needs cure time.
Well, thanks everyone. I'll let you guys know how it runs. I've gotta
run around and I'll set it tonight.
Hopefully I'll be able to "move fast one a dime"
(as opposed to stopping on one, :P )
James Sweet
The metal hose is supposed to be routed so it isn't touching the turbo,
it probably got pushed in the way at some point, or the motor mounts may
be shot and allowing the motor to move around.
circuit slave
into that as well.
There is a metal band on the side that holds the heater hose--it was
held in place but not securely.
Thanks for the info---oh and forgive all my misspellings. : )
Boris Mohar
Do not forget to cover the hole with a small metal disc. Otherwise you are
likely to get the epoxy inside and gum up your turbine. That thing spins
over 100,000 RPM. You don't want to unbalance it.
Regards,
Boris Mohar
Got Knock? - see:
Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca
void _-void-_ in the obvious place
circuit slave
Boris Mohar
I was browsing through my Turbobricks forum and stumbled on someone's
project.that shows a turbo with a similar wear mark except that it has not
gone through. Look at the third picture from the bottom
http://forums.turbobricks.com/showthread.php?t=63571
circuit slave
hehe, just joking--- I know which one you were referring to. :P
I put the dime on with JB Kwik and will then seal it with the regular
weld.
I'll post an updated pic when I'm done. Also let me ask you Boris, if
you might know. Have you ever changed the oil seal from the oil return
line on the turbocharger?
I gotta leak that's been like that forever (or should I say, the
previous owner had). Is it difficult? I hear about being careful not
to pinch the seal---I'm just hoping I can get to it with a rachet
extension. I haven't tried yet, but I want to try tomorrow.
Boris Mohar
No I have not (yet) Maybe someone here knows, else visit Turbobricks
Maintenance and nonperformance section of the forum and ask there. You do
not have to register.
circuit slave
some details.
thanks, I'll check there, too.
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yet. But just to see, and it's helped alot! However, when I go into
boost near the back of the car I still hear the flutter---what it
sounds like ( only when going into yellow turbo on the guage) is what
sounds like is a rapid drum roll sound ---it's like light rapid
rain---like a snare drum roll rapidly with a wire brush.
Maybe an exhaust leak or something on the catalytic converter ?
muffler ? I don't smell anything or exhaust fumes ?
BTW, there is light smoke smell on the engine. I think the oil trap is
blocked. I pulled the oil cap loose and it jumps around. Who knows
when that thing has been cleaned/changed.
Maybe that's why I got the oil leak on the oil return pipe.
James Sweet
The real fun is when the old gasket sticks firmly to the turbo and you
have to spend an hour scraping it off with a razor blade. Usually it's
got enough oil soak to come off, once I had it stick very firmly, though
thankfully the turbo was on the bench at the time.
circuit slave
I do that I had to "buy some time" and cleaned the oil trap instead of
replacing it. Man ! that thing was clogged like an artery ! The car
had been smelling like it was burning oil--open the engine lid and you
could see smoke. I even did the oil cap test and not only did it jump
around it spit oil out.
Now nice suction ; ) I'll replace the oil trap soon--I don't think it
has ever been changed or looked it. Man, what neglect this poor car
had. I'll seal the hole later. I tested it out and maybe I
shouldn't have--'cuz the JB kwik now looks like a scab beginning to
peel. Maybe I didn't wait long enough for it to cure.