Nissan: 91 Pathfinder - exhaust manifold leak

"5k8r" <net> wrote in message news:<CPIPb.102130$nt4.317492@attbi_s51>... 

No, it's not reasonable, if it's fixed right the first time. However,
the pathfinders do have that problem over and over when an
inexperienced mechanic replaces the studs and manifold. On my 91, I
replaced all the studs with "updated turbo studs" from a nissan
dealership. It broke within a year. The nissan dealership blamed it
on not using a specialty snap-on stud installer, but I beg to differ.
I think the problem is with the pathfinder cylinder heads, because I
replaced one of my cylinder heads with a used one from a maxima and it
has not had the problem in over 3 years. The other one continues to
break. I have heard that countersinking the stud hole a little
prevents the stud from snapping off due to heat. This time around
instead of that I just replaced the one broken stud without removing
the manifold and simply didn't turn it in all the way we'll see how
this works. Snap-on tools sells a stud extractor set made by Rigid
which has a 1/8 inch drill bit guide which can be used along with a
foot long 1/8 inch drill bit from under the passenger side fender well
without removing much of anything, makes the job easier than an oil
change and I would consider 350 bucks highway robbery for this job.
The driver's side is a much different story due to many engine parts
being in the way of the manifold. Unfortunately I don't have a solid
answer for you I have been fighting this problem with my pathfinder
for a number of years and have even considered thorley headers instead
of the manifolds to remedy the problem. I'm pretty confident it can
be fixed by someone who is intimately familiar with the other VG30E
engines such as the ones from the maxima and the pickup, because those
ones don't seem to have the problem. I'd suggest talking to different
mechanics until you find one who knows what's going on and will stand
behind his work for a longer period. Either that or just go pay 15
dollars, get the stud extractor and an 1/8 inch drill bit long enough,
and horse it back together for now

Woah!!! The main reason you are having problems is due to
warpage of the manifold. Even .010 warp will cause problems.
When ever you have problems like this is critical that the
manifold is removed and resurfaced at the local cylinder head
shop. This only costs around $18-25 and will end the problem
permanently. Better shops can bake the manifold to stress relieve
it a few cycles, then recheck and regrind if needed. It is also a
good idea to install the studs like you mentioned since they are
cheap. I had to install Heli-coils since my warped manifold actually
pulled the bolts out, stripping the threads. Even brand new manifolds
should be checked. Just because they look OK, is no guarantee
that they are really flat. Just a bit of extra checking will be worth
the
large outlay if something shows up in a year or so. Worked for me!!

"matt" <com> wrote in message
news:google.com... 
news:<CPIPb.102130$nt4.317492@attbi_s51>... 
me out 
100k on it. 
and I have 
engine 
rebuild, and I 
reasonable, and why 
However, 
it 
differ. 
it 
well 
solid 
instead 
those 
different 
stand 
enough, 

I had my manifold resurfaced by the same shop the local nissan
dealership uses, and it still broke the bolts again in about a year.
I've also had trouble getting it resurfaced correctly.



"Johnboy" <net> wrote in message news:<supernews.com>... 

Matt, you did everything correct, so I'am out of real suggestions!!
Everything I mentioned will lessen the warpage, so there must
be something else thats the culpret. Did the shop give you
any numbers on the final resurfacing? Maybe the downpipe
needs another tie point? Whatever you find, make sure we hear
your comments. Good luck, hope you solve things!
Johnboy
 

Have you replaced the manifold???
Nissan says to to replace studs and exhaust manifold with new parts.
Improved parts
"matt" <com> wrote in message
news:google.com... 
news:<CPIPb.102130$nt4.317492@attbi_s51>... 
it. 
have 
and I 
why 

Sure, and you get to pay for the whole thing yourself because Nissan
claims no responsibility for its mistake. I have two Nissans ('94
Quest and '95 Pathfinder) and they both have the infamous exhaust
manifold design/implementation problem. I can understand that mistakes
can happen, I've even made one or two myself over the years, but not
admitting it and leaving the customer swinging is unconscionable. No
more Nissans for me.


On Sat, 24 Jan 2004 20:27:16 GMT, "brystok" <rr.com> wrote:
 

As a Nisaan Master Tech I have done tons of exhaust manifold and studs,
when done right with the right parts I have never had a problem. On the '96
and '97 Pathfinder Nissan extended the manifold warranty to 100k, so can't
say they customers "swinging"
"warren" <com> wrote in message
news:com... 
out 
on 
engine 
and 

Okay, but who paid for those tons of exhaust manifolds and studs?
Was it Nissan? I don't think so. I'm not questioning the competence of
the Nissan Techs in doing the repairs. I'm saying that Nissan made a
design/engineering/spec mistake but we have to pay to correct their
mistake. This mistake was propagated to several years worth of
engines. It was identified and better studs were shipped to dealers to
fix the problem so Nissan knew that it made a mistake, identified the
fix then denied all responsibility. To do both sides on either of my
vehicles would take over a $1000 US out of my pocket. That's why I
said they left me/us swinging.

And since I have neither a '96 or '97 Pathfinder, they could have
extended the warranty to 1,000,000k and it wouldn't do me a bit of
good.

Just feeling a little cranky today. I think I need some sunlight in an
environment that's more than 10 degrees F. 8-}

On Mon, 26 Jan 2004 19:18:38 -0800, "brystok" <rr.com>
wrote: