91 Pathfinder - exhaust manifold leak

Hello Newsgroup,
I am female and claim no technical genes exist within me, so help me out here . . . I have owned my 91 Pathfinder since 94, and have put 100k on it.
It is still in beautiful condition, well . . . It has 186k now, and I have fixed two exhaust manifold leaks, one of which was included in an engine rebuild 1-1/2 yrs ago. Only had a one year warranty on that rebuild, and I am now being told that I AGAIN have another exhaust manifold leak!
The auto repair shop is quoting $350 to fix it. Is this reasonable, and why would I continue to have this problem?
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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 :D
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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!!

me out

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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.

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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

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Have you replaced the manifold??? Nissan says to to replace studs and exhaust manifold with new parts. Improved parts

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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.

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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"

out
on
engine
and
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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-}
wrote:

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warren wrote:

Go try Ford. Their automatics have a defectively designed planatary gear carrier. The carriers regularly crack and break, destroying the trans ($2500+ to fix). They've known this problem exists for years yet all you can buy is another defectively designed one. They may still be using this part today? At least Nissan redesigns parts that have a problem rather than just selling you another defective one. -That- is leaving you swinging.
--

Steve

http://www.atlantaracing.com
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Hello Group, I have looked at my records from the shop that did my engine rebuild (part of which was fixing an exhaust manifold leak)and I can not tell whether he replaced the manifold or not.
I will call him tomorrow and ask. As I mentioned, this is my third manifold leak with the car, and since it is in such exceptional shape otherwise, I do want to fix it and keep the car. My engine rebuild had a two year warranty attached to it, which ended 8/03. The leak became apparent 12/03.
I wonder whether the folks that fixed it will feel obligated to do something for me. Thank you all for your suggestions for my "clacking" engine.
I'll post again after talking to the rebuild shop.

out
on
engine
and
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