latino914

So guys I have a 10x with 90k miles and I've been having to fill up on coolant every other day. There was no visible leak when checking on top or no puddle on street. So when I took it to the dealership they did a pressure test and told me it was leaking from the water pump. They quoted me $1800 parts and labor. Ive looked around at other shops and gotten estimates from $500-700, which is alot better. So what I want to know is when replacing the water pump what else should I be replacing?
from what I know is the 2 radiator hoses and coolant to refill system. Also ill be purchasing a aftermarket water pump from Beck Arnley.

I havent found many threads on this topic which is why I'm asking and surprised that I I have this issue which is rare for our vehicles.

Crazyirish

OEM water pumps are around $70. I would go for that over the BA.

JSolo

iTrader: (14)

Strange to find an internally mounted water pump leaking. What exactly did their pressure test reveal? Where specifically was it leaking from? Do they have pictures?

SonicVQ

^^^ Yes, very strange....

On the G37, if the water pump is leaking the coolant is getting into the oil.
Pull out the dip stick and see if the oil looks milky.

If there is no external leak, there is only 2 places the coolant can leak to: Engine oil, or combustion chamber.

latino914

There is no coolant in the oil whatsoever and the car doesn't overheat. The dealership did say it's uncommon and only saw one other G in his time at the dealership for it to leak from there, but that's where its coming from. No he didn't take a picture of the leak. He mentioned they have to remove the timing cover off which is why it was pretty expensive.
what do you guys recommend I take it somewhere else to do another pressure test just to be sure???

blnewt

iTrader: (13)

If you do end up getting it fixed since you have a 2010, make sure they take a look at the oil gallery gaskets that are prone to failure on pre 2012 models, if this were to fail it would be another trip to the dealer w/ at least a $2k price tag.
G/L

SonicVQ

Please ask your dealer:
(1) With the water pump behind the timing cover, how do they know it is leaking, since it can't be seen?
(2) Where is all the coolant leaking to?

I am not trying to pick a fight with you or your dealer.
I want to make sure what is wrong is fixed, so you don't pay more.

On one side of the water pump is coolant, the other side is a timing chain and oil return. (lube for the chain) I might be wrong, but I can't see it being the water pump.

On other cars, the water pump is mounted externally and it is VERY easy to see a leak. The G37's water pump in mounted inside the timing cover.

Anyways, if it is the water pump, I would only use OEM.
(but is isn't )

blnewt

iTrader: (13)

Sonic VQ always has great advice, not worth saving a few bucks on the water pump as it's a major job if it goes bad again (assuming it's bad to begin with). The bearings on OEM water pumps are substantially better than almost all aftermarket brands. Aisin is one aftermarket brand that is also an OEM supplier so they are a good choice as well.

latino914

Thanks for your input, I'm actually going to go to another shop and have another pressure test done and see where they say the leak is coming from. I'll report back from there.

latino914

So just got done getting a second opinion and the mechanic says it seems to be coming from the water pump but not 100% sure since its behind the timing cover. He was diagnosing the leak for about an hour and from his knowledge, he's pretty certain that the water pump is where the leak is coming from. So I guess ill be replacing the water pump soon.

RMB5190

iTrader: (2)

I'm kind of with the rest of the internet on this one. If no one can see the pump due to it being internal then how could they possibly deduct that's what is leaking; especially after not finding traces in the oil?

Is this a trusted mechanic who is a Infiniti specialist because honestly, he could just be coming to the same conclusion as the dealership due to a lack of understanding of how the VQ is designed; especially if you told him what the dealership told you.

latino914

I didnt mention anything to him about what the dealership told me, he came to this on his own conclusion. He was very honest and detailed about his observation. Either way to be absolutely sure, he would need to take the timing cover off to make a final decision. So if anything I can always return the water pump I bought.

JSolo

iTrader: (14)

^^The part itself is rather cheap compared to the hours of labor involved.

If coolant is leaving the system through some means, unless it's getting burned, there still has to be some physical evidence of this. The pump itself is just an impeller of sorts (look at this link for pics) driven by the timing chain . If either of the sealing seals are leaking, coolant would be mixing with the oil.

It's a tough call to make. How much is the labor portion of the repair bill? If that doesn't fix it, are you out the money?

latino914

Labor around shops not the dealer is around 500-600. I already have the new water pump from aisin. The dealer did say that its probaly coming from the weep hole. So with two shops already telling me that its the water pump I'm probably just going to have it done and have them see of any other possibilities where it could be leaking.

JSolo

iTrader: (14)

If they guarantee that will fix the repair, go for it. If not, what happens to the money paid....

See, even if it is leaking from that weep hole, it would be an internal leak. Water pump goes into a casting in the block. Coolant doesn't disappear into thin air.

This is from the 3.5L, but similar design on the 3.7

http://cdn.revvedmag.com/image/2015/...g-vq35de16.jpg

The water pump is at the 1:30 position relative the crank sprocket. From the looks of the pump, it doesn't appear to have a traditional inlet/outlet design, but rather generates pressure by moving fluid within the block.