First off, I am by no means a mechanic... but my oldest son is certified in Nissan, so I talked him into tackling the coolant pipe replacement on my 2006 Cayenne S.

Thanks to this site and a few youtube videos, he got the job completed in one weekend...
200 miles later and yet another coolant leak has appeared... And it is much worse than a drip too.

We tore back into where those coolant pipes were he installed the "upgraded piping kit" and everything seems to be find on top on the motor.

We took the belly pan off and put pressure on system thru the radiator cap, and coolant just pours out of what looks like two little weep holes on the bottom of the bell housing...??

I am sure it is coming from the back of the motor, but we are having a hard time getting behind there to see what else could be leaking.

My son works a full time job so I am just trying to get some needed info on what to start looking at first.

Thanks

 

Did you replace the plastic coolant T's while you were in there? These are another common failure point (cheap plastic) and will drip down onto the bell housing.

 

I am pretty sure the "coolant Ts" are only on the turbo.

 

I did not replace any T's... We took the intake plenum off and felt around behind the top of the motor and cant find anything wet.

When we put 8 lbs of pressure to the system, it has a steady drip coming down the driver's side of the bell housing... at 10+ lbs, it is a steady steam coming down too.

Looking up from under neath, I can see there is a coolant hose hooked to an aluminum pipe that comes down beside the bell housing too... but that aluminum pipe is completely dry.

I am guessing it is something leaking on the left top of the bell housing, but I can not find it at all.

We have used a mirror and small hands... can't find anything wet at top of the motor.

 

Well,

Still no luck on finding this leak...

I did however find a local shop who has offered to put her up on a lift and help me sort thru it.

I am worried they will have to drop the transmission just to figure out which one is leaking tho.

 

The only thing I could think of would be the distribution mount where it connects to the block. But, I've never actually heard of this leaking.

Let us know what you find out. If they have to drop the tranny, make sure they replace the transmission seal as it will likely start leaking. They usually do when coolant gets on them.

 

If your car is a turbo, the coolant tees could be suspect, but the would leak on the outside of the bellhousing, not the weep holes.

The engine valley drains into the bell housing through holes near the starter. Unfortunately, from what you describe it sounds like your new pipes are not seated/sealed correctly in the water manifold, or one of the three rubber hoses at the back of the engine that connect to the pipes are leaking into the valley.

If you have access to a bore scope/camera, you may be able to confirm where its leaking by looking under the manifold at the back of the engine and along the back of the engine on the left hand side to confirm before digging in.

Good luck in your fix.

 

It isn't a turbo it's a S model.

After putting pressure on the system we felt every hose that our new aluminum pipes were connected to and couldn't feel any fluid what so ever. We don't have a bore scope/camera so we are strictly going by feel. Could there possibly be a spot where hands couldn't feel? We put about 150 miles on the vehicle before it started leaking......? We are totally baffled and by no replies on here it sounds like others are too....!

 

From what you describe, it sounds like your leak is in the valley under the manifold. But I'd hate to send you in there with only a hunch.

But again, thats the only place where coolant can get into the bellhousing from what I saw when ai did my pipes.

I've seen borescope/inspection cameras at Home Depot and Harbor Freight for less than $100. That may be an option before you commit a half day's work (or more) to remove/reinstall the manifold.

Good luck.

 

Found it! I guess we just needed to walk away a few days and give it a chance to rest cause today when we put pressure to the system the leak was as plain as day!


Embarrassed to say but it is coming from the recent pipe change out. Its where the larger pipe fits into the fitting. Haven't started tackling taking it all back out yet, any way that job is easier? My son is in Atlanta today at the MX race but will be home tomorrow, hopefully I can get it back on the road soon!

Thanks for the suggestions and sorry to bother everyone with installer error..........grrr.

BTW, how many of you have had to do this job over? My regular mechanic said it was about 1 in 3 to maybe 4 that had to be pulled out and redone.......just curious.

 

Glad to hear you found it, sorry to hear it's under the manifold.

The ECS instructions suggested both pressure and vacuum testing before reassembly, which is probably a good idea. I bought their vacuum tester/filler and it worked great. It could probably be modified with air fittings to also test pressure (I forget how much, but it's pretty low psi) or you can buy a pressure test cap. Those additional steps reduce the risk of a subquent leak, and the vacuum tool made filling a breeze.