LoSRx7

Quick question. Do I need to use some RTV sealant on the gasket that goes in between the housing and engine??? If not, should I???

thx

LoS

LoSRx7

ttt

SureShot

RTV is always a good idea on water seals.

Jimmy325i

I don't use paper gastets on mine. Just glue them together with the rtv.

RX729

Can you connect the water pump to the engine just using rtv or is the gasket needed?

Cory Simpson

I would seriously suggest using a gasket unless you want to take it off and do it again later. RTV won't hold as much pressure as a gasket will, Someone RTVed the hell out of the filler neck on an RX-7 that we just sold, and all of that crap popped out, and started causing the car to overheat. Just use a gasket it is better than RTV.

Cosmo Donk

I hate RTV It makes a mess. I have found that the Mazda gaskets work great if you make sure to clean off the housing so it mates nice and smooth

SureShot

Let's see I pulled the water pump housing & split the gasket, part stuck to the motor, part on the housing, no pieces missing, sunday PM, no new gasket available, need the car Monday.
To reassemble I painted a thin coat of RTV on both parts.
Let it set like the directions say.
Bolted it back up without overtorquing.
It hasn't leaked in two years.

RTV is not filler, but it's a great sealer that makes future repairs easier.

Jimmy325i

When done properly, as sureshot just mentioned, it works great. Question me? Look at the damn FSM for the proper procedure for installing the oil pan. Humm, they say either use a gasket or use RTV.

When you do it right, there is a few thousanths of an inch of RTV in the seam. The joint is stronger than a paper gasket, simply due to the fact that it is adhered together, and is so thin that the load seen by the actual gasket material is minimized by the very surface area of the seal.

I personally like the clean up of this method hands down over a paper gasket. I use acetone to clean the barely visible former layer off the metal. (since there's only enough RTV there to fill the pores in the machined surface of each part) And then you're ready for the next one.

Preformed Silicone gaskets are far superior to paper ones. RTV is just another way of getting a silicone gasket. Why do you think they recommend it for assembling trannies, diffs, oil pans..... Yeah, It's better. Thats why.