laspisa

Hey everyone, pretty new to the LS world, just got a 2002 Z28 last week, nice car and only has 60k miles on it so I am pretty stoked. Bought it knowing it had cooling system issues. Found out that the radiator was cracked, plastic strong! Anyways ordered a new one from NAPA and it is exactly the same as the old one except it has an extra coolant fitting, ~5/8" on the bottom driver's side of the radiator. Can't figure out what to do with this, don't want to cap it off with a old piece of hose and plug, crappy thing to do on a new radiator and one more place to leak! Anybody had this problem? I already went back to NAPA and they rechecked the part numbers and everything is legit.

Another issue is that I thought I would change the thermostat while I was at it, the new thermostat plus housing (they are built together and they don't sell them separate...) doesn't fit into my water pump???? The guy at napa pulled out a replacement water pump and it does fit in the new one, but not the one on my car...

Need some help!!! Thanks in advance

msydow

i have always had to cap those fittings off on aftermarket radiators. as for the t stat, ive heard of this before, but dont remember the solution. try a search on here. good luck with the car btw.

LS6427

iTrader: (2)

You my friend have an LT1 radiator right there.............but whipe those tears away....you're in luck.

An LT1 radiator is better than an LS1 radiator...and it fits into the 4th Gens 100% identically and perfectly. You will never know you just installed the wrong radiator. I did this as an upgrade years ago to my 1998 Trans Am. Everything hooks up normally.........

Also, that extra port is a great addition. Look at my picture below. Go buy a 1 foot long piece of heater hose, two clamps, and any type of threaded metal plug that will screw into the end of the hose. ((the picture shows my white plastic plug, I now have a brass threaded plug)) Just go to the parts store and play with there stuff till you find the right plug that fits good. Then put it on and clamp the ends. My brass metal plug screws in and out of the hose end when I loosen the clamp, then it screws right back in and I tighten the clamp.

It makes for an amazing way to flush your radiator. You never have to mess with the stupid, SLOW ***, petcock drain again. Plus the petcock drain can break off because they get briddle over time. I flushed mine this weekend....its a breeze and the radiator drains in 30 seconds.

So don't worry, put that LT1 radiator in and you will have much more cooling capacity. My 427ci in hot *** South Florida runs cool as a cucumber.

.

LS6427

iTrader: (2)

Post an up-close picture of your t-stat and housing. Mainly want to get a good look at the t-stat as its mounted in the housing.

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guy7bmwm83

iTrader: (5)

I ran into the same thing with the thermostat. The water pumps were redesigned around 2003 and use the separate thermostat and housing. It sounds like you may have the redesigned one. I ended up buying a thermostat listed for a GTO, which came with the redesigned pumps. At first, they sold my the single piece unit, which doesn't work. The parts guys don't know much other than what the computer tells them.

wssix99

iTrader: (5)

Is your car a manual? The online GM Parts catalog says that's for an "auxiliary hose." Maybe folks with automatics use it?

GM changed the water pump design around 2000. That being said, your 2002 should have come from the factory with the new design. Either NAPA was showing you an old pump and an old inlet or someone replaced your pump with the old design before it was still available as a replacement part. If you get the number off of your water pump casting, you should be able to figure out what you have.

laspisa

Hey guys, first off thanks for all the quick responses. Looks like I have to deal with the extra fitting, but like LS6427 says I can use it for a nice drain. Definitely need to flush the system, old owners tried to use that stop leak stuff and everything is pretty gummed up.

Here are some pics of the water pump, the old thermostat and housing, then the new one the parts guys gave me. Like the idea of it combined, just don't fit! Trying to cross reference the water pump numbers but no love yet. I will head to the shop and ask them for a GTO thermostat and see if that will work. Thanks again for all the help

laspisa

Forgot to add that the car is an automatic.

guy7bmwm83

iTrader: (5)

I found this thread.

https://ls1tech.com/forums/generatio...n-correct.html

wssix99

iTrader: (5)

You have a new pump design and those jerk-offs gave you an old design thermostat. Just go back and have them look up the part correctly for a 2002! The old thermostat has three holes and the new body only has two. (The third hole was for a wire loom attachment which was ditched on the new design.)

laspisa

Thanks for the thread link. I had done a search on the radiator but couldn't find anything, so I didn't try with the thermostat. I think I am all set now. I will go get the correct thermostat tomorrow. Crazy things when the parts don't match up on a stock application, oh well.

LS6427

iTrader: (2)

My t-stat housing is that German made brand. Its like the one pictured on the left. The t-stat DOES come out so it can be replaced with a new one. You push it downward and twist it, that unlocks it from under those two brackets.

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pewter2002

iTrader: (4)

So I just ordered a new thermostat/housing from GM for my 2002 LS1 car. P/N is 12571261, is this going to work for me?

wssix99

iTrader: (5)

No, I don't think that's it. Google images and you'll see that its the old type.

Here's the cross reference to the new pump for the AC Delco and GM part numbers. (page 2 - http://www.acdelcotechconnect.com/pdf/10JTI-064.pdf) I think 12600172 is the one you want. (This is what I just put on my car when I replaced my water pump and it looks exactly like your old one.)

RockAuto used to have a really good cross reference for these parts, but it looks like they don't carry the Delco thermostat anymore so all that info is gone now.

In defense of your parts guys, this particular part is really screwed up, which is why there is a special bulletin (above). I have an old GM parts list and it shows the old part, even on the 2002.

pewter2002

iTrader: (4)

Apparantly, the p/n *I* listed is for the new type of pump and associated inlet/thermostat. I just looked at my setup on the car and it has the 3rd hole in the housing for a push type retainer. Correct part for my 2002. Now, how do I do a flush by removing the thermostat and circulating water through when I can't get the thermostat out of the housing? I tried the push/twist method mentioned earlier, how hard do I have to force them apart? Sorry about a hijack here, OP!

wssix99

iTrader: (5)

If you aren't the original owner, its possible that you have the old style pump on your 2002. In the end, you'll want a thermostat that matches what you are removing.

If you have the stock cooling hose setup, you don't need to worry about bleeding air. It will self-bleed through the vent tube. You'll have some air collect in the radiator from this, but after two warm up/cool down cycles on the engine, the expanding coolant should push the collected air from the radiator out through the overflow tank. (I just did this with my water pump replacement and it was all good.)

guy7bmwm83

iTrader: (5)

This is how I plugged the extra opening. It is a brass plug with a female/male connector found at Lowes/Home Depot. Does that radiator have the low coolant sensor? My 2001 doesn't have that sensor so I bought one to close that opening.

laspisa

Everyone, thanks for the help in figuring out this radiator/thermostat deal.

Like recommended I went in and bought a 2004 GTO thermostat, it was a little different looking but fit in like the other one and seals up good.

I did the same thing as LS6427 and guy7bmwm83, actually got a little brass petcock, pretty slick and was real handy when flushing. Although it started leaking after I flushed the coolant. Have to get back under there and try some teflon tape and tighten up the clamps.

Radiator works well, runs solid at right under 210 on the indicator so should be all good. Car runs good! lot quicker than what I was expecting actually.

Now I just have to figure out a humming/oscillating noise coming from the right rear at speed. Stops below 25-30ish. Saw a thread on maybe it might be a hub?

Thanks again

wssix99

iTrader: (5)

I'm curious - what was the part number you ended up with?

laspisa

wssix99,

I just went to O'reilly and got this one:

Murray Caps & Stats - Standard Thermostat
Part # 45687

http://www.oreillyauto.com/site/c/de...3442&ppt=C0331

Fit no problem and everything seems to be working good.