Originally Posted by user52165
Originally Posted by Mad_Hatter
Originally Posted by Number_35
Originally Posted by slacktide_bitog
I haven't, but I consider them a must in cars where it's hard to change the spark plugs on. I am smart enough now to avoid buying cars like that, but if I ever do for some reason, it's getting ruthenium!
Hard to avoid now, with how common transverse V6 engines are, and how most engines have gone to a DOHC configuration.
The plugs in our V6 Kia took me 4 hours. In the inline-4 Mazda they took 20 minutes.
I have that transverse 3.9L v6 Kia engine where the plenum has to come off. I've gotten it down to about 2hrs to take off and put back on. I've had to do it a couple times once to replace the plugs (ngk ix iridium) and coil packs (OE Hyundai/Denso) and another couple times to fix a vacuum leak because the plenum gasket didn't seat. Oh, I also pulled the fuel rail and cleaned each FI with Gumout. I thought about sending them in for ultrasonic cleaning but the Gumout treatment worked great. I bench tested each one before putting them back in with all new rings. I also put in a new O2 sensor on that rear bank 1 (keeping the old one as a backup), so in theory I shouldn't have to take that thing off for at least another 5yrs.. we'll see. One thing I would advise anyone is be careful torquing those plenum bolts, I found out the hard way that they break easily and had to have one drilled out by a friend
I will admit that the first time taking it off and putting it all back together took me close to 4hrs like you mentioned.
Essential to use a NEW plenum gasket.
Torque on those bolts is quite low - typically about 15 ft/lbs.
I know the 5.7 HEMI's call for 105 INCH lbs for the manifold. I believe the upper manifold for the 3.6 Pentastar is 71 inch lbs. and yes, always replace the gaskets, they're cheap.
