waterpump backing plate gasket?????

[bx8lugger]

I'm about to do my waterpump on my 93 k2500, the factory manual says to seal the backing plate to the motor with anarobic sealant and no gasket, but I see that felpro ans ssdiesel supply sell one and my motor has a gasket with red rtv between the motor and backing plate. Do I buy the gasket and seal it with rtv or use the anarobic sealant?? Which is better to seal it???

[AllThumbs]

I think there is a thread somewhere that says sealant alone is OK with new motors and parts but may be suspect with older equipment and a gasket is a safer choice.

Don't take my word for it, but you should be able to find it. I know I read it, but can't remember where.

[rameye]

ditch the gasket...by the reccomended sealer!

[Robyn]

Put the gasket on with the RTV sealer (used sparingly) the sealant is fine for all new parts but, used equipment will work much better with the gasket and the RTV.

Been there done that, many times.

You will never have a leak with the gasket and RTV.

The problem with the sealant on a used block and steel backing plate is simple, the block etches as does the steel plate and with this etching comes the great likelyhood of a leak when using only sealant.

The one place I use the sealant only (RTV) is the valve covers.
The anerobic is also fine for use on the rear main cap to block area around the rear main.

Missy