Oldssupreme

Hello everyone! As i am beginning to clean up my Olds 1972 350 engine and put things back together, is there a good rule of thumb as to which gaskets go on naked, which get sealant (and what type) and which should get sprayed with adhesive over or under the gasket? I have a fel-pro full engine gasket set. Thanks guys, you have been such an amazing help to me through this entire project!
Chris

olds 307 and 403

Any rubber no sealant needed. Cork, I like either RTV or Aviation sealant or Gaskacinch. Think about if you had to pull it apart for any reason. You need rtv at minimum where the cork pan gaskets meet up with rubber end seals. Also needed around BOTH sides of the water ports on the intake pan and most put a good high bead of rtv on both ends of the intake in place of the rubber seals. I also use RTV on the thermostat gasket with sealant on the bolt threads, I actually use double gaskets. Also get the Neoprene rubber seal in place of the rope rear main seal.

VIKINGV8

Hi Chris & Hudson. Ive never used a spray adhesive to hold gaskets in place. I rely on Indian Head gasket shellac for that purpose. It works great when used sparingly, looks like molasses & a little bottle will last forever or until it dries up. Good Luck on the resto.

svnt442

If you ever look at an engine that is factory sealed you will either see a gasket, or gasket maker (a sealer), but never both. You will see sealer where two gaskets meet, but again never on the face of a gasket.
I have used copper spray as a tacking agent to a gasket won't slip on me, but I learned a long time ago not to put RTV on the face of a gasket because all you do is make a mess.
Remember, if you see RTV ooze out, it's also oozing in.

Oldssupreme

Randy, VikingV8, and Olds 307 and 403, thanks for the tips. I certainly appreciate it!
Chris

oldcutlass

On valve cover and oil pan gaskets I like to use weather strip adhesive to glue them to valve covers and pan ensuring they lay flat and don't move. I use RTV in the corners of the front and rear pan to block seals as suggested the rest of the gasket face is installed dry. Valve cover gasket joints between gasket face and head are installed dry. Most composite gaskets are spray tacked to the removable part not the engine. On metal intake gaskets I use RTV as suggested for the water ports and use the front and rear supplied seals in most cases with RTV in the corners.

bccan

Quality of gaskets has to play in here somewhat. Some gaskets are more substantial than other brands or versions. I usually rub a film of RTV on thin paper gaskets, a thin bead of RTV on water ports. Diesel pan gasket, Perma Dry Plus valve cover gaskets don't need anything. Thick fiber style (mr gasket, fel pro performance) intake gaskets don't need any sealer added except @ the end rail joint - either a full bead or dab if using the end gaskets.

I actually spread anti seize on thermostat & carb base gaskets so they can be disassembled without any sticking or tearing as I frequently will reassemble this areas w/ old gasket.

Oldssupreme

Thanks so much guys! Much appreciated!

Oldssupreme

One more question... Is it okay if there is any fresh paint in the areas where gaskets will sit? I primed the outside of the timing cover with VHT primer, but now I'm wondering if I should sand the primer away where the water pump gasket will go or will it not matter?
Thanks!
Chris

distributorguy

Gaskets go on white-glove inspected clean bare metal.
I use Permatex #2 gasket sealant on cork and blue gaskets, both sides. RTV sparingly on rubber manifold end gaskets to make sure they stay put (read and follow the instructions) and black RTV in the corners between different gasket materials. I hate leaks, and this process has worked in my last dozen or so motors with absolutely zero leaks. You also have to be sure your gasket surfaces are straight and spotless or its all futile. Oil pan and valve cover rails are always bent, twisted, overtightened so you need to take the time to fix them!

quaddriver

You got some good advice in this thread...but most important: no paint oil or grease on any metal surface (most critical for example is tranny gasket, if there is ANY fluid on the pan or case surface, tranny fluid will 'wick out' the area FOREVER, regardless of gaskets or sealants used)

personally: if modern rubbery stuff - no sealant. on intakes I use the glop of rtv in the corners (on other makers you can discard the rubbery end gaskets and use an rtv bead). on cork, I like RTV and sometimes use permatex #2 aviation, but man I hate that gooey sticky stuff, it gets everywhere....

If the gasket is steel, like an olds intake, I rtv EVERY port with 3 types: rtv copper on the exhaust crossover, blue on the water port, black on the intake ports

head gaskets: I spray with copper spray or use indianhead shellac - unless absolutely instructed not to by the maker

now mind you, this advice is good for olds, dont transfer such knowledge blindly to anything much newer you might work on...gaskets are different, O2 sensors are sensistive etc. Olds only!

Oldssupreme

You guys are amazing! Thank you so much!
Chris

Oldssupreme

Does RTV go bad sitting in a tube for 20 years? I found an almost full tube of clear silicone RTV in my garage that i havent used since 1998. Can this be used?
Thanks,
Chris

oldcutlass

I would toss it and get a new one. We aren't talking big bucks here.

distributorguy

Clear isn't a good choice either. Each color has different properties. Read the tubes. Ultra-black is the best between varying gaskets, like in the corner between rubber and metal or paper or... You may need a couple options on hand. They last a few years at best.

Oldssupreme

I purchased the permatex Ultra Blue RTV. The package said it was best suited for old cars...

distributorguy

Read the instructions. blue is good for valve cover gaskets and water pumps. That's about it. I hate blue. I don't use it - ever.

olds 307 and 403

As said, Ultra Black is probably the best all around. Red or Ultra Copper are good choices just due to their temperature resistance. The Right Stuff is also good but pricey. Clear is better for non motor applications where you want it more invisible. I have had success with Ultra Blue but some have claimed it didn't cure properly. You should be fine with it.

Oldssupreme

Thank you!