Hi all, I'm helping a friend work on his one-owner 1990 M30. He's got leaking rocker arm cover gaskets. Removed and replaced the passenger side gasket in short order. My question is about the driver's side cover removal. I've removed the air cleaner and plenum up to the throttle body. The cover is bounded on the front side by the AC compressor and on the firewall side by the throttle body/intake manifold collector. My question is what part(s) of the throttle body/intake manifold collector need to be removed. The answer could be none, just the throttle body, or the whole collector. I just want to hear from someone experienced before I dive in. And if I get an answer, the group has more knowledge than my local dealer who hasn't seen an M30 in almost 15 years for maintenance (their statement, not mine). Thanks in advance for you advice. It's page 58 of the service manual but I'm not able to post the image here for some reason.

I had slight leaks at the covers - all I ever did was tighten the screws. Did you ever get it apart?

Actually, I did. The existing gaskets and the grommets were worn thin - -tightening was not an option. I removed the air box and disconnected the air plenum (but it stayed loose down low in the engine bay; I never actually pulled it out. I loosened the intake collector with the throttle body attached. I also loosened the bracket for the AC compressor. The AC compressor bracket stumped me because the FSM shows 2 bolts and the Infiniti parts diagram shows 3. I wound up loosening 5 or 6 bolts to get enough play to squeeze the valve cover between the compressor and the distributor.

I avoided taking the air collector completely off in the hope of saving some of the old, very brittle hoses. However, when I put it back together, I realized that the existing plugs were fouled and had a lot of corrosion where the tip inserts into the plug wire. So, I removed the collector completely, replaced plugs, wires, cap, rotor, quite a few hoses, and reinsulated (self-fusing tape) or protected (split loom) more wires and cables where protection had dry rotted over the years. Hopefully, my buddy won't have to have the collector pulled again for a long time.

Two more issues - the front bolt of the collector (short one) broke before I even tried to torque it. I checked the four longer bolts and at least one showed signs that the threads were stretched. So, I went on a bolt search. Nissan had the shorter bolt but Nissan and Infiniti were unable to locate any of the longer bolts. I had the same experience online. So, I went shopping for any socket cap 8m 1.25 55mm bolts. The only ones I found were from a place called Accugroup in the UK (I'm in the US). I ordered 4. My only concern now is galvanic corrosion between the SS bolts and the aluminum intake. What to do...it's been a puzzle.

check out a company....
pencomsf.com
they make all types of metric stuff...lots of long sizes