Coolant Leak | Crossover Pipe Gasket

[tabrown11]

For my 2001 Infiniti QX4, I have a bad coolant leak that I have traced back to the Crossover Pipe's passenger-side Gasket. As I have done research, I have discovered that there are two ways to approach gaining access to the crossover pipe's passenger-side gasket: either to remove the upper and lower intake [for the approach from the top] or to drop the transmission [for the approach from underneath]. I am going to take the top approach, following these instructions to remove the upper and lower intake: threadlocker-on-power-valve-screws-pics-t304263.html.

And, I will follow the instructions in these articles to replace the crossover pipe gasket: post6617894.html?hilit=Coolant%20Leak#p6617894, post6577992.html?hilit=coolant%20leak#p6577992, & http://www.nicoclub.com/FSM/QX4/2001.5_QX4/lc.pdf.

There are two things I have questions on:
- What gaskets do I need to complete the job? I plan on replacing the gaskets for the upper and lower intake as well.
- While I'm back there, what else is advised that I change?

Thanks for your help!

[Buzzman]

- While I'm back there, what else is advised that I change?

Check and loctite your power valve screws, and replace your PCV valve.

[atraudes]

In case the other discussions didn't cover it already, check out CanuckQx4's post here.

The Fel-Pro MS91241-1 and 61343 gasket sets will give you all the gaskets you need for the intake manifold/plenum and throttle body. For the crossover tube, this parts diagram should show you what you're looking for. I've ordered from infinitiparts.com before and had great experiences, too, so I recommend them if you're going to buy the parts online. Give them a call if you have any parts questions; their customer service was really helpful when I talked to them.

[4xq]

Good stuff from Buzzman and Atraudes.

I would replace the water control valve and hose (page LC-17) while you are in there. That is really a second engine thermostat. They cause engine overheating if they stick closed.

You might also take a look at retailmenot for Advance Auto coupons - they have up to 40% off on orders of 110.00. Sometimes the coupons make for some really good deals.

[tabrown11]

Great information. Thank you guys! I'll let you know how it goes.

[tabrown11]

I have an update and a question:

- I was able to remove the upper and lower intake, and remove the four nuts off of the studs for the crossover pipe. The problem I am having now is moving the crossover pipe along the studs, away from the engine, to gain enough clearance to remove the old gaskets and replace them with the new ones, because of the hoses attached to the crossover pipe.
- Referring to page LC-17, do I need to detach the water hose [#4] from the water outlet housing [#1] and the hose that attaches to the left side [facing the back of the engine] of crossover pipe to gain enough clearance to replace the two gaskets? If so, what techniques/tricks do you know of to remove those?

Thank you again for your help!