2008 G37S Coupe 6MT - 97000 miles.

I have a major overheating issue.
Thinking it was a thermostat - that was changed but we discovered a leak now.
My mechanic says coolant is leaking out of the engine from the water pump area and is spilling all over the thermostat.
He's having a hard time to locate exactly where it's coming from.
We will be trying to change out the water pump for lack of better ideas.

Things that have been changed in the past:
1. Radiator hoses a year ago
2. Heater hoses a year ago
3. Thermostat was changed about two years ago (this is the third thermostat now)

QUESTIONS:

1. Has anyone had experience with a leak like this before?
2. Is it possible I blew a gasket or have engine damage?
3. If I have to buy a new engine - will any other year fit besides 2008?
Most of what I see available is 2009+

 

theres a weeping hole in the engine block coolant will leak form if the water pump is going bad which is where it sounds like the leak is, unfortunatly gettign to the water pump on this car means taking apart the front end...if youre doing that you should change the oil gallery gaskets to the newer metal ones...

I'm not sure if I've interpreted it correctly but I understood from your post that the leak started after the thermostat replacement...that being said from the history you described could it simply be the thermostat gasket was not reinstalled/not installed properly?


if you have to swap...any VQ37VHR should work from any year, even from a 370z

 

I read his post to say the overheating led to several attempts to fix easily, starting with the thermostat.

 

I had an overheating issue in summer 2017 that changed thermostat the first time.
Then another overheating issue about year ago that was heater hose (I changed the radiator hoses at the same time).
Now this time - mechanic started with thermostat (he did mention gasket but changed that with the new thermostat).
Then discovered the leak after changing thermostat.

 

The constant overheating would certainly point me to a failing water pump... the area where the leak is described is consistent with this as well...

Where theres overlap with the thermostat gasket being the cause (or the thermostat itself) is the leak area would be almost the same (or appear the same) and the "discovering" of a leak after the thermostat install..perhaps he overtorqued the thermostat and ruined the gasket or didn't clean the old gasket properly or just used a crappy gasket....these are things that happen when someone rushes the work and tries to save time/cut corners and isnt that uncommon....either way..the cost is about $10.00 vs. $3000.00 so probably wouldn't hurt to rule it out first...

If this was a car that had an access cover to change the water pump easily (like on the old G35s with the VQ35De engines) I'd say say just change the pump and then try other stuff but because you basically have to tear the front end apart I'm suggesting start small

 

perfect. i just ran out of the warranty 1-2 weeks ago.
just had to do spark plugs coils and intake. i had a misfire issue and just got it back 2-3 days before the overheating.

so... we're going to do the water pump.
you mentioned to also replace oil gallery gaskets - thanks.
anything else i should know for this job?
anything to make mechanic's job easier?
he's worked on our cars before but has not done water pump - but he already know he needs to take off timing cover, front-end, etc.

 

you may want to consider changing the timing chain, timing chain guides and tensioner too while you're in there

One thing ppl seem to have trouble with is breaking the crank bolt loose, but your mechanic may have a trick for this and it may not be such an issue cause your car is a 6MT..other than that its not that its a difficult job, just very time consuming because of the amount of disassembly required...

the good news is that if you change the water pump, galley gaskets and do the timing chain and associated parts, the engine should be good to go for a very long time

 

1. water pump
2. galley gaskets
3. timing chain
4. timing chain guides
5. timing chain tensioner
6. LABOR

Let's see if I can afford all that in one shot.
New engine is roughly $2000 more or less depending on mileage.

 

I'm taking a look here: https://www.z1motorsports.com/engine...-4_36_111.html

Can someone help me figure out exactly what I need?
I see gallery gasket here: https://www.z1motorsports.com/front-...et-p-8880.html
Looks like I'll need two timing chains: https://www.z1motorsports.com/front-...in-p-5898.html
I only see one timing chain guide, looks like the "short" one is missing: https://www.z1motorsports.com/front-...de-p-5899.html
I don't see a timing belt tensioner unless it has a different name on the website.

EDIT: I spoke too soon and found this: https://www.z1motorsports.com/camsha...t-p-12470.html

 

good news is the price of parts isn't too bad:

You can buy a kit from Z1 with all OEM parts and add the gallery gaskets for about $491 including shipping if it helps...thats the best price I've seen for OEM parts...

you can get a kit using aftermarket parts and an Aisin (OEM supplier) water pump for about $249 from Rock Auto total includig shipping...add the cost of the gallery gaskets (about $33) and your still under $300.00

Its the labour that kills it

Edit: the Rockauto price is using a 5% off coupon (google it, theres always one active)
good luck!

 

sorry I posted above before seeing this post....you are correct this is what you need

 

So I should be OK with the Timing Kit with water pump and order the oil gallery gaskets separately?

I saw this: https://www.z1motorsports.com/front-...it-p-9484.html but that doesn't include the gallery gaskets.

 

yes with respect to order the timing kit with water pump.

the link you posted is for ALL gaskets involved in the job and I would definitely order it if I were doing the job but i think some people skip it and reuse most of them... if you do order it use the drop down box to add the gallery gaskets for $32.00 (you save $1.00!)

To be clear you should have 2 things in your cart at Z1:

1. Timing Kit with Water pump option selcted
2.Timing Cover and O Ring Seal kit with Upper and lower Gallery Gasket Set selcted

Lastly you will need some RTV....if your mechanic can't get this/figure this out ....get another mechanic

I hope thats clearer

 

I'm going to discuss with my mechanic.
I'm on the fence of maybe saving that extra cash for the timing chain stuff for a possible new engine (if I still have a leak or engine damage from heat).

 

hey man going through this issue now, would i need new cam chain tensioners for this or can i re use the ones it has?