I had to access my Plenum 3 times now. First to install the original MD spacer months ago, then the ISO thermal kit, and lastly I had to go in there again to review my installation of the ISO kit due to an error code of 1283 popping up after the install a few weeks ago.

The lower plenum, at least mine, cannot tolerate this much activity. I now have 5 completely stripped threads. 3 around the perimeter and 2 in the center bolt group.

I torqued properly each time using a good quality in./lb wrench. Well regardless of the care, the threads could not stand up to the repeated access. Needless to say I am going back to stock when I receive the new lower plenum that I will order today and I will stay stock.

I have to take the car to the dealer to find the 1283 issue and I will not risk another plenum being ruined by putting all the mods back in afterwards. Tony from MD mentioned to me in an email that he has noticed the some castings are soft, with some softer than others. I guess have one of the softer ones.

 

Jeez! That blows man... I've had my upper off twice now and was planning on going in a third time to install the iso thermal spacer. I didn't have a torque wrench at the time so I used the hand-torque method with the bolt driver instead.

Maybe I'll stick with my hand tightening method instead of using the torque wrench...thanks for the post.

 

helicoil inserts can be used and would have saved you a few hundred dollars.

Just drill and tap the next largest hole size and thread in a tangless free running insert (and use red loctite to hold it in place). You will be able to install and remove the upper intake manifold 100 more times w/o a problem with these areas ever again.

 

i have a snapped bolt stucking in the hole, i do i get it out?

 

i know you say you torqued to the specs provided, but aluminium can withstand only so much when steel bolts are being put in and out in and out.
sucks you had to get a new one, but i would just wait to see what nissan says and then put it back on. it will not hurt to open it up once and put your spacer back on. i would tighten it slowly and by hand. when i thought it was right, crank the car and listen look for leaks. tighten until gone.

 

that sux, what dealer do you take it to?

 

If it's snapped off flush w/ the surface, use an E-Z out. If some of the screw is sticking up above the surface, use a pair of plyers and gently back it out.

 

I'll be going to Bill Siedel's on 107th Ave.

 

I thought of this option. But if the code 1283 turns out to be more than a bad O2 sensor, say an injector or injector harness, the dealer will have to go in by removing the plenums and would see the repair and probably invalidate the warranty for this particular problem.

That is the reason I decided on a new lower plenum.

 

Anti Seize is a must for steel bolts in aluminum
Take it from a person who's built many Gixxer/Honda Motorcycle engines
Aluminum will gall in a heartbeat

 

I've had the exact same problem. Many stripped threads, even with a torque wrench. It's why Hydrazine and I couldn't test my car with just a stock plenum when we first tested out his spacer on my car, because the threads were stripping, and I needed to at least have the car operational for work the next day.

I've fixed the problem by running bolts from the underside of the plenum. Then you can use a nut to secure the top portion. It works very well, and if you use steel bolts, you don't have to worry about stripped threads anymore.

I've used helicoils and timeserts on our soft aluminum, and the aluminum AROUND the inserts stripped when tightening to anything over 7 ft lbs.

 

That must be because Nissan uses cheap cast crap.

 

I have had my plenum off a total of 5 times now and have 0 stripped bolts. 3 of those times were in one weekend. So just be careful with the the torque and you should be fine.

 

torque wrench to do a plenum install??? all u really want to use is a 1/4 inch drive and use one hand to tighten the bolts... this stuff is aluminum and can strip very easy. tap bigger threads and use a standard size bolt. i forget which size, i stripped one on mine but it was my fault but it was an easy fix.

 

Nissan must have some big time variability in their casting process or materials.

I've opened up mine over 20X and still no problems. But I sure have seen some collectors that seemed really soft and brittle. They could use a little more QC in their casting department.

 

if it is flush with the surface you can use a dremel to cut a slot in the top and then use a flat head driver to screw it out.

 

I refer to an in./lb torque wrench. The bolts spec is 60 in/lbs or 5 ft/lbs. Even hand tighteneing stripped thread on my plenum. The first time around I didn't have an in/lb wrench so I used your method and a couple stripped right off the bat. As Tony says the material quality is quite variable on this part.

 

damn nissans!

 

Remember the 60 in-lb wrench's accuracy is MUCH DIFFERENT than 5 lb-ft wrench's accuracy. The more gradiations the better the accuracy. I would NOT recommend using the 5 lb-ft torque wrench.

 

+1

That is why I have both. The right tool for the right job. It didn't matter this time. The plenum material is toooooo soft!