DACTARI

iTrader: (1)

Hello Gents,

Well, here we go again. I've got a slow coolant leak that leaks only when the car is driven. If it sits, there's no leak. The top hoses are fine, as is the bottom rad hose. No leaking there. However, there is a general seeping down from the center of the engine area that I can't pinpoint. Also, the lip that juts out under the harmonic balancer is wet, as if there is water running down behind there. Could this be the water pump? I'm thinking most likely it is.

What can I do to confirm the diagnosis?

If it is actually the water pump, what do I need for new installation in terms of water pump (part number for 06/LS2), gaskets, etc? Also, is there a good writeup anywhere?

Cheers,
DACTARI

BigTuna819

iTrader: (1)

betting its the waterpump. you can usually tell by looking up from underneath the car, its probably leaking from the weep hole. I had the same problem back in june. I ordered my replacement thru rockauto, I also swap in new belts while I was in there. Pretty easy fix tho

jeepster666

I had a hell of a time finding this leak also. Mine was the radiator! It only leaked when under pressure and it was blowing water back onto the engine while driving so I kept looking for it. I finally let it idle from cold to full temp while I watched and it was from the top of the radiator! Between the aluminum and plastic end tank.

Its worth a check and way easier to change than the water pump!

DACTARI

iTrader: (1)

I replaced the radiator a couple months ago because it was leaking from the top tube connection. The plastic neck coming off the rad had basically rotted and snapped. After replacing the radiator, my leaky days were over till the cold weather started, and I began to get some seeping from below/behind the water pump. Pretty sure it's either the water pump or the gaskets behind it. I'm planning to replace both the pump and gaskets. Found a good price on a pump on Amazon:


Also ordered some RTV silicone gasket maker for the gaskets:


While I'm at it, I may switch out my 160 tstat for a 170 because my freeway cruising temps are so low now that it's cold out, I can't get the cabin to heat up enough so it's comfortable for my wife and child. Engine temp when freeway cruising lately has sat around 145-150. Anyone have any advice on what I can do about this, other than change out the tstat?

FuzzyLog1c

iTrader: (4)

I've been getting heat in less than 90 seconds on my car with a 160 degree thermostat. Must be the tune. Next time your wife wants more heat, you should show her how much heat a second gear pull up to 6500 RPM generates.

DMM

Same here...although I am running between 111 and 135. I'll just throw the stocker back in for the time being.

DACTARI

iTrader: (1)

wow, that is COLD-- i just ordered a 180 LPE stat. no interested in draining my coolant every season to get at the stat.

http://www.lingenfelter.com/mm5/merc...ode=L310055204

DACTARI

iTrader: (1)

So my stock replacement AC Delco water pump just arrives. The gaskets are folded together. Is that normal? Can I just unfold them and use them or try to get hold of new gaskets?

FuzzyLog1c

iTrader: (4)

If you could post a picture, that would be helpful. They shouldn't be folded in half, if that's what you mean. They should look like this:

DACTARI

iTrader: (1)

Here's what I got in the box with the pump. It was probably the best boxing job I'd ever seen. That **** was TIGHT. Then this:

FuzzyLog1c

iTrader: (4)

Those gaskets have been destroyed.

DACTARI

iTrader: (1)

Yeah, I figured. OK, gonna get a new pair. Thanks, Fuzz.

DACTARI

iTrader: (1)

Just popped in the 180 thermostat. Does anyone know if I need to use RTV silicone gasket maker or similar on the thermostat housing?

DACTARI

iTrader: (1)

Got this done yesterday. Took me 4 hours, 1 hour of which was spent trying to free the 6-year old hoses from the original water pump. Wanted to report back on some details in case it might be useful for others.

Firstly, all the steps are very straightforward. There is nothing complicated to this, but getting access to the water pump was a much bigger pain in the butt than I'd anticipated and involved removing more parts. Maybe this is due to my relative lack of experience, and other guys could get by with doing less, but this was my experience. Beyond removing the fans and the air intake tube, I also had to remove the MAF and loosen the LPE airbox to get the fan out. I also had to remove the thermostat housing before removing the water pump, in order to get enough room to pull out the fans (Had to remember to take the thermostat housing off the new pump so that the fan would clear on the way back in). Also, in order to get the water pump to clear, had to remove the idler pulley. The hoses attached to the water pump were a massive bitch to get off. I used a flat head screw driver to pry them up and they spray silicone grease in there to loosen them up. Suggest you do this early and let them sit to loosen up. Everything went back together super quick.

Specifically, with regard to the RTV silicone, I finally understand why it's needed. There is simply no other good way to get the gaskets to sit where they need to be while you're gingerly lowering the new pump in those tight spaces. If one slides slightly out of place and you crank it down wrong, then you're ruined your gasket. I wound up using a good smear on the stuff on the pump side only, then slid the pump into place.