Sealants, Threadlock, Anti-seize, Grease and Lubes - When and where are they needed? (1 Viewer)

[Oakley40]

For most it may seem very obvious and routine, but for many of us that are learning Mechanics 101 on the fly, the simple things may cause the most grief if not done correctly.

I've been looking all over the place for a tutorial on what goop to use on parts and when to use it. I would like to start a guide (if there isn't already one that I missed) on when to apply the above-mentioned goops, what needs it (and what doesn't), how much to use, and what surfaces to apply it to (both sides of gasket, one side, around bolt holes, etc.). If you have input please mention what you use and why (flexible, permanent, hardens, not for parts that get hot, etc.). Maybe at some point it can be put it in the FAQ's for those newbs like me.

We all love pictures, so add 'em if you got 'em.

So to start, here are some areas that I have questions about and some off the top of my head (parts are probably not correctly named on many):

1. Water pump to block
   1. sealant?
   2. threadlocker on bolts/nuts?
2. Intake/Exhaust manifold bolts and studs?
3. Intake/Exhaust manifold gasket?
4. Exhaust flange bolts - anti-seize or threadlocker?
5. Carb to manifold?
   1. bolts need threadlocker?
6. Engine mount bolts to block and frame?
7. BH to block bolts?
8. Trans to BH?
9. Radiator housing to frame?
10. Fuel pump?
11. Oil filter housing
12. Block drain
13. Main bearing caps
14. Cam lobes
15. ???

 

[Steamer]

I believe everyone has their own preferences for various reasons and the more you wrench, you’ll most likely develop your own. Mine are a bit unique and I wouldn’t try it persuade anyone to do as I do. In general, I believe sealants improve your chances of not having a leak but then you need to scrape that stuff off if you take it apart again plus you’ll lose the gasket.

I happen to hate scraping gaskets so I’m a big fan of never seize. I only use sealants in a very few select places. Like between the valve cover and the gasket. The gasket it glued on to the valve cover with Permatex and then never seize on the bottom of the gasket. I can take the valve cover off numerous times and use the same gasket over and over with no leaks. Differentials and covers, side cover, water pump, t-stat housing, timing cover, transmission top plate, pretty much everything gets never seize and I don’t do any gasket scraping and get to re-use gaskets if I don’t have a new one handy. I’m not cheap. I just like the speed of pulling a cover and getting it back on quickly without scraping.

Someone here awhile back said they’ve been using Sil-Glyde where I use never seize and have had excellent results for several years. I’ve made the switch a while back and like it quite well.

A lot of folks wouldn’t do what I do, and I certainly understand. Good luck on making your choices.

You wanted pics so here's a few.

 

[Dizzy]

I use motor oil out of an old fashioned squirt can for things non-exhaust related on the motor, they make exhaust-specific anti-seize. I also use a wire brush to clean threads, so that I can spin them freely with no tool and I can get a good and even torque. Carb to intake won't need anti-seize for an OEM thread, but motor oil because I want them to do no gall damage to the aluminum casting. Trans to bellhousing would also be a wire brush cleaning and motor oil, because I want to properly torque the screws without additional friction resistance.

Screw stretch is important, and it is what prevents fatigue, oiling does not make them loosen prematurely if correctly torqued. I'm a big fan of Tri Flow oil for light duty threads, not in the proximity to rubber; I also use it on lock cylinders. BTW, they are all 'screws,' in my vocab, regardless of size, unless they are accompanied by a nut, then it is a 'bolt.' But, if you are talking about 'head bolts', then I know that it is just a customary mechanic term, and I will put my machining/machinist theory book away for the moment.

Some Land Cruiser headers require that you basically glue the intake to the block, as they are not made to metric standards, otherwise, nothing on the manifold(s) gasket.

Something like the radiator housing to frame might get polyurea axle grease that I use on my bicycle. Phil Wood is my favorite brand, sorry no pics. For things exposed to road salt, precipitation, or the car wash. without a rubber-type material close by, then I use a grease. The OEM radiator frame actually had a canvass spacer that was sandwiched there, and I greased or oiled that too, as there was evidence of rust, I hope that was not a mistake.

The motor mounts in the back use cotter pins. I drilled holes thru the nuts and staked them with pins because I used generic bolts before SOR started offering the OEM style bolts again. No grease or oil because of the proximity to rubber. However, I wonder if dielectric grease would be best used on these threads, it is made for rubber spark plug boots, specifically, and it offers corrosion protection by being an electrical insulator which is at the heart of the rust process? But, basically, I decided to assemble them dry and deal with the consequences.

I once heard that oil or grease should not be used on certain springs because it can create a situation akin to case-hardening, and it would leave the exterior surfaces brittle and lead to cracking. But I really don't know if you can grease springs and not have problems.

On the water pump, I used oil, but I still question that. The last thing that I want is to have to remove more rusted pieces of sheared screws from the block. Threadlocker is good for preventing corrosion? I actually had chunks of RTV stuck in water passages of the head when I took the head gasket off, so, if I'd go that route, I'd use it sparingly.

 

[middlecalf]

Phil Wood is my favorite brand, sorry no pics.

Wow, haven’t seen that reference in a long time. My tube is about 1/2 gone.

 

[Oakley40]

I appreciate @Steamer and @Dizzy for sharing their tips and perspective on what they do and what works for them.

So is Permatex and FIPG overrated or unneeded? If not, what do people use it for?

 

[Dizzy]

Formed In Place Gasket and Permatex would be my answer for stamped sheet metal that has lost its flatness, or never had it, due to assembly/disassembly or whatever. I'm thinking about the push rod cover on the engine or the PTO cover on the transmission. My 2F thermostat housing had a hard time sealing, so I might reach for some there. Also, there is rust deficit in the front of the block around the water pump. It might have been warranted there, but so far it is holding. The very top lip of the 2F valve cover gasket was secured with Formed in Place Gasket when I started on this motor, but I also spent quite a bit of effort cleaning it off when I replaced the cracked gasket. It received motor oil much like the oil filter, so it would not seize to the surface, particularly with the heat of the engine.

I failed to mention that many of the screws which have baked-on dirt and oil go into a vapor-tight glass jar of gasoline. They rest there for the night until the next day when they are easy to clean with brushes and or brake cleaner. When the gasoline gets dirty enough, it gets filtered thru a pour-over coffee filter set-up. I also use this for bearings on my bicycle which have cages that trap dirt and hard grease that might not be easily accessible to clean without slightly bending the cages to release the bearing balls.

The small screws that are used on the inside of the valve cover for the PCV cover received that cleaning because they were coated with the crusty oil of the inner valve cover, and they needed non-permanent Locktite, as it would be a disaster to have loose fasteners in that space. I also used brake cleaner, and a screw or rethreading tap on the valve cover itself to prep the receiving holes for the fasteners.

 

[cult45]

Permatex Aviation sealant was recommended to me and is a great, non drying formula for mating surfaces in both oil and water applications. Can get ugly if you overdo it though.

 

[4Cruisers]

I use copper anti-sieze on the steel bolts in the aluminum thermostat housing - helps prevent corrosion from dissimilar metals. And Permatex threadlocker red on the sensors in the thermostat housing.