upstatemax

iTrader: (15)

I removed my upper intake to tighten down my rear exhaust manifold and I noticed while putting it back on that two of the bolts that run through the upper intake down to the lower intake to tighten it down had metal shavings in them... sure enough the lower intake manifold is stripped...

I cannot tighten down two of the front bolts.... what can I do to fix it????

Can the holes be re-tapped???

or do I need a new lower intake??

s0ber

iTrader: (7)

mines are stripped also, but it doesnt leak, you might be good...

you can retap them if you want, i believe using helicoils?

upstatemax

iTrader: (15)

what ones are stripped on yours? The two front ones are stripped on mine, I still have the the two studs on the side, I am just worried it will leak.

DandyMax

iTrader: (7)

I had a problem with two of the holes on mine, so I went out and bought some longer bolts (IIRC 150mm long for the 2 front ones) and there seemed to be enough thread in the LIM below the area stripped by the stock bolts that the longer ones still grabbed fine. No problems since. I also grabbed a tap and cleaned up the hole (and threads) before installing the longer bolts, but this might not be necessary.

I think the problem was that Nissan's bolts aren't long enough and with heat and the softness of aluminum, if the bolt is tightened a bit too much, there isn't enough thread to hold it strongly and the result is what you described. Moral of the story, don't torque the bolts too far, and only do it when the manifold(s) are cool enough.

Curt

iTrader: (27)

Don't know if this will help you guys with the striped threads, but I'm guessing that most are getting their 00VI's without the 2 brackets that supported the back end of the 00VI to the rear head on the 2000 & 2001 Max (I believe they're not the same supports that the 4th gen uses). With that weight cantilevered back there, it will want to be pulling the 2 front bolts out of the lower IM. Proper support should prevent the problem, and you ought to fix the striped threads with either Helicoils, or better yet, KeenSerts.

s0ber

iTrader: (7)

Yes the 2 fronts

upstatemax

iTrader: (15)

It is the first time the Intake has come off. So yes the two brackets were holding the back.

Thanks for the help guys, I am going to get the Helicoils today and my brother is going to help install them (he is a mechanic and uses them often).

DandyMax

iTrader: (7)

Did you try using longer bolts first? It's probably cheaper and will likely work - it did for me... but hey do whatever you want to.

Curt, I too have a rear bracket so I don't think that's the major reason.

krismax

iTrader: (15)

Maybe you guys dont know this (apparently not) but those bolts are suppose to get 10-13 lb ft applied to them ,not 150

DandyMax

iTrader: (7)

Oh don't worry, I always check the torque spec on things. Mine stripped at about only 8-10 ft-lbs! At the time I was saying to myself, "WTF.. it wasn't even over spec?!" lol.

It's ok, the longer bolts seem to work fine for me now.

EDIT: just checked the FSM.. spec is actually 8-11 ft-lbs

upstatemax

iTrader: (15)

As I said in a previos post, it is the first time the intake manifold has been off.... So they were still at factory torque specs, when I backed them out for the first time the threads just came with the bolt...

upstatemax

iTrader: (15)

I did not try the longer bolts.... I am worried it will be a PIA later on down the road. My brother has used the Helicoils in the past and swears by them, so I will give them a try.

s0ber

iTrader: (7)

using a torque wrench the bolts stripped on me, its like unavoidable.. lol ah well..

where did you guys get teh longer bolts from???

DandyMax

iTrader: (7)

Any hardware/fastener wholesaler/distributor should have them.

williamgd2

I had the same problem on 4 of my intake bolts,I just changed the bolts and they cougt nice and tight. It seems the threads on the stock bolts are not deep enough. I was not looking forward to tapping and threading them but did not have to. You peeps try just changing out the bolts.

MOHFpro90

iTrader: (11)

What compelled you to bump a 4 year old thread to input on something that has already been solved?

HandsonMaxima.

iTrader: (2)

for people like me that only had 2 front bolts in and now have an idea to fix it. no leak no care but i like a sturdy manifold.