Water pump gasket question

I'm going to replace the water pump (finally) and I need to know if I should just use the new gasket that came with the water pump, or if I should scrap that new gasket and just make my own with RTV sealant, or if I should use a combination of the new gasket and RTV. I have heard different things about the subject and I just want to do whatever will provide a long lasting and reliable seal.

Thanks for your help.

Use the gasket and get yourself some of this stuff to seal it: http://www.permatex.com/products/Au...tex_Aviation_Form-A-Gasket_No_3_Sealant_a.htm

I'll never use RTV on cooling system components again after using the aviation sealant.

x2, the gasket and the Permatex. Torque it right, and it will be fine.

I always use Permatex non-hardening on thermostat housings, with the gasket.

Clean both mating surfaces ENTIRELY, use a bright light to inspect the mating surface on the engine--the thinnest piece of old gasket left on there can ruin your day.

Apply a couple of small dabs of the Permatex to the thermostat housing where the recess is for the thermostat--it will hold the thermostat in place when you install the housing. Apply a small amount, a thin layer, of permatex to the mating surface of the thermostat housing, and put the gasket on the housing. DON'T put any sealant on the mating surface of the engine, you don't need it and it will be a PITA to clean up next time. Put the housing in place, start the NEW stainless steel bolts you bought for this project and run them down finger tight. Using a 1/4" ratchet and socket alternate turning each bolt a small amount at a time. If you don't you run the very good chance of breaking the housing. Once both bolts have been tightened down equally, just snug them both down, you don't kneed to muscle them, just make sure they are tight.

joe_peters said:

Put the housing in place, start the NEW stainless steel bolts you bought for this project and run them down finger tight.

Click to expand...

I've never purchased new bolts for this and have to swap t-stats in the next few days...do you happen to know the sizes of the bolts?

Sorry, been a while. I had to run up to the hardware store and took them with me. On the Renix one is longer than the other, and off-the-shelf lengths weren't exact. Rather than grinding them down I used a couple washers to get the right fit.

PM 5-90, he may remember the size.

The longer bolt I removed was fairly corroded, I was surprised it didn't snap off.

From 2000 parts manual.

.312-18x.970

So that means 5/16-18, 1" long.

winterbeater said:

From 2000 parts manual.

.312-18x.970

So that means 5/16-18, 1" long.

Click to expand...

Both of them? Maybe just the Renix has the long and short bolts.

joe_peters said:

Both of them? Maybe just the Renix has the long and short bolts.

Click to expand...

Alldata shows 1 long 1 short for my 97. Also, looking at a picture of the thermostat housing(hesco) shows it would need 1 long 1 short.

I'm replacing my thermostat soon and would like to replace the bolts while it's apart if anyone has exact sizes .

My 96 HO has a long and a short. Thanks for the info, guys. Mine wasn't bad the last time I did it, but it's not a bad idea to change while I'm in there. I've more than likely got the right ones on the shelf here at work anyway, now that I think about it.

jeeperguy21 said:

I need to know if I should just use the new gasket that came with the water pump,

Click to expand...

I just did mine, but I replaced the pump with a Flowkooler pump. It came with 3 different thickness gaskets.

Without the right gasket the impeller would hit the block.

I'm sure the stock pump will be different, but something to think about.

Use a gasket......

I did my water pump a couple months ago. Used the gasket it came with (NAPA pump), and applied Indian Head to the pump side of the gasket, dry on the block side - found that technique here on , but can't remember who originally posted it.