New exhaust, blown gaskets. ??s

[Tedward]

Howdy Land Cruiser Fans. 1st thread I've started here.
95 LC. Stock. 2 inline cats.
405,000
Had shop install new oem exhaust manifolds, magnaflow y-pipe and 2nd cat, oem muffler a d tail pipe. Reused newer upstream O2, brand new 2nd O2. Both oem.
Started making noise/leaking in 2 days less than 100 miles.
Gasket between 1 connection at y-pipe to manifold and gasket between 2nd cat to muffler are blown. They tell me it's running very hot. Point to the blueing of the new y pipe. They say this is why the gaskets are blowing out and leaking. I don't know what to make of this info. The original exhaust did not leak. I replaced it just to di it before I had a problem. Ooops.
The CEL is on. I have tried the paperclip but don't get a code.
I am hoping to drive to Massachusetts from Ohio in a day or two.
What can I make of this?
Please give me advice as what to do now.
Edit.So, I should have waited before posting. Probably just loose hardware. Going to double nut the cat flange studs. Also, going to use studs and double nut the y pipe flange to .maniflods. I'd delete this whole post if I could from my phone .
Thanks in advance,
Ed

 

[mingles]

Were the gaskets OEM or aftermarket? In particular, I have been told that it is common to have (manifold to Y-pipe) aftermarket gaskets fail. Edit - I see now that you did reference OEM gaskets. Are you/they sure they properly tightened the associated flange hardware? Additionally I would think that blueing of a new SS Y-pipe is to be expected

My own situation is that I had new cats and y-pipe installed 30K ago. About every 3-5K the bolts on the manifold to Y-pipe will loosen up to the point that, if left unattended, gasses will start to leak by the gaskets and eventually burn them out. I'm on my third set of manifold/y-pipe gaskets and it is now part of my regular PM to check the tightness on the manifold/y-pipe nuts. I'm about due for another set of gaskets as the front manifold one is leaking again. I long ago removed my heat shields so checking the bolts is a two minute task. The only harm from a small exhaust leak in that area for me is that it will blow towards my AC line and reduce the efficiency of the AC.

I have no CEL and don't think the engine is running lean or hot. My theory (just my gut instinct, no proof) as to why those bolts keep loosening is that my motor mounts need replacing and there is too much engine movement during driving that works those bolts loose.

 

[BILT4ME]

The bluing is to be expected.

It should NOT leak. The bolts/nuts should NOT be working loose. They should be double-nutted if they can be and to prevent working loose. I would suggest locking nuts, but those usually result in broken studs.

No, it's not running hot.

Use a torque wrench. Torque them frequently during the first 200 miles. Catch them as quick as you can so it doesn't burn out your new gaskets.

 

[JeepinPete]

The Magnaflow gaskets will burn out. BTDT. Their pipes and cats are great, gaskets not so much. Replace with OEM gaskets, problem will be solved. Might we worth replacing the nuts with new OEM parts too. I R&R'd mine one too many times, stripped the studs. The job is a much larger pain in the butt once that happens. Don't let that happen

 

[Heckraiser]

Also if you're using original studs on those manifolds, they may be stripped or bent. Mine are, so that's on my short-term to-do list. Replacing all the gaskets and all 4 studs.

 

[inkpot]

This is not YOUR problem! It is THEIR problem. Talk to your credit card company about withdrawing payment and I would bet that THEY fix it right.

 

[mingles]

If it weren't for my MUD OCD, I'm sure I could have flipped this over and got a few more thousand miles out of it .

I R&R'd mine one too many times, stripped the studs. The job is a much larger pain in the butt once that happens. Don't let that happen

Did your studs strip in the manifold flange or where the nuts go on the stud? One of my studs stripped this AM in the manifold flange. I have it through bolted for right now but need to order new studs and see if the flange thread can be saved.

 

[JeepinPete]

Where the nuts were. It took 15 nuts welded to the studs to break the rust bond and get the four studs out of the two manifolds. That was a fun day...