# Water Pump: Liquid vs. solid gasket?



## gcturp (Feb 11, 2008)

I am replacing the water pump on my 1994 2WD truck. I have everything removed (fan shroud, fan, belt, and finally the old water pump) and I am ready to install a new water pump (OEM thermostat too). But I have a question about the sealant for the new water pump (and thermostat):

Should I use an aftermarket gasket ($2 and seems it would be very easy) or the liquid sealant? Or both? I have searched the forum, but have found no definitive answers (I found posts for all of the above options, none of which were necessarily supported or questioned).




BTW: This is an easy job to do - definitely can be done without much trouble for a first-time DIYer. (If something goes wrongs, I will edit this post!)

Thanks for your time and responses.


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## smj999smj (Jan 1, 2006)

I've always just used RTV sealant. The key to RTV is make sure the surface is clean, apply the appropriate size bead of sealant (don't smear it on) and let it set for a few minutes before you install the part. If you apply it properly, it'll last until the next time you need a t-stat or waterpump. The problem with paper or cardboard gaskets is that they do break down over time. If you do go with a paper gasket, don't apply RTV to it; use liquid gasket adhesive or copper spray gasket.


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## gcturp (Feb 11, 2008)

I have a finished replacing my water pump (original, 1994) and thermostat (original too). I also changed the alternator belt (probably a few years old) and replaced the clamps on the lower radiator hose. Surprisingly the radiator hose looked great, inside and out, after 17 years of use. 

After 1 day (about 30 miles) of driving - no leaks and the temperature regulation is spot on.

I purchased a new Duralast water pump at autozone ($35), the belt at autozone ($8), and the thermostat and the nissan dealer ($23). I spent about $80 for everything; I was given 2 quotes at $400-$450 from two local shops.


I decided on the liquid gasket. Everybody I talked to - autozone guy, nissan dealer technician, and this forum- discouraged solid gaskets. I used the Permatex Ultra Grey RTV (available at autozone, $7). It was much easier to use than I anticipated. 

I purchased a 10 mL syringe (Syringe - Wikipedia, the free encyclopedia) at a pharmacy and squeezed enough of the RTV in the body of the syringe (about 2 mL) and delivered the material this way, without the needle on the syringe. This delivered about the right width of material and it was very easy to push down the syringe barrel at an even rate. 

This is an easy job - only need a few common tools: Phillips screwdriver, 10 mm wrench, ratchet set (10, 12, 14 mm), razor blade to clean away the old gasket material, some brake-clean to thoroughly clean the surface prior to RTV application, and finally a broom handle to re-position the alternator. 

The most difficult part of this job was getting the radiator shroud out and back in. Another difficult part is tightening the bolts on the water pump, and especially the thermostat. The thermostat housing is tightened with only 4-6 ft-lbs (no torque wrench I have ever seen goes that low)! I tightened the bolts a 1/6-turn past finger-tight and I will keep an eye out for cracks or leaks in the next few weeks. I tightened the water pump bolts 1/4-turn past finger-tight.

I used mostly the FSM (http://www.********.com/FSM/hardbody/1994/) as a reference.


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