1995-1999 4thgen Nissan Maxima Valve Cover Replacement Notes

Credit: 99sagelimited

I recently decided to replace both of my leaky valve cover gaskets and clean up the engine bay a bit. Along the way, I ran into some issues that I’d like to share to forewarn other members.

Issues Encountered

Coolant hoses
When I removed the upper intake to access the rear cover, I had to cut two coolant hoses that connect to the back of the intake. I couldn’t reach the clips, so cutting was my only option. These hoses are Nissan-only parts, so I had to wait a while to get replacements.
Fuel rail and spacers
Since the lower intake manifold gasket was included in the intake gasket kit, I decided to replace it as well. I didn’t relieve the fuel pressure beforehand and instead pivoted the fuel rail assembly out of the way.
- The first time I reinstalled the rail onto the lower intake, I forgot the spacers and torqued it down.
- After realizing the mistake, I removed it and added the spacers. Unfortunately, the fuel rail tabs had bent from the mishap, causing a major vacuum leak that stumped me for several days.
- To fix this, I ended up using smaller spacers to properly seat the injectors in the lower intake, along with installing new injector insulators.
Fuel rail bolts
The bolts that secure the fuel rail to the lower intake strip very easily. I stripped one and had to re-tap it with a 3/8-24 bolt.
RTV sealant on valve covers
You must use RTV at the sharp edges on the front and rear valve covers. Most people know this, but I neglected it and had to redo both covers. I also recommend using either the OEM Nissan gasket or the Fel-Pro one.

Lessons Learned

I ended up removing and reassembling the upper intake four times. By the last attempt, I could disassemble and reassemble everything in about an hour. While I had the engine apart, I also completed the following work, and now the car runs awesome: