Oik Pan: Rtv Essential For Ls

RTV is a type of sealant that is used in various gasket repair jobs, including oil pan repairs. It is typically applied to the corners or stepped areas of the engine to fill in gaps and assure a leak-free assembly. When installing an oil pan, a small amount of RTV is applied to the corners of the gasket and/or stepped casting areas. This helps to create a lasting seal and prevent leaks. It is important to follow the manufacturer's recommendations and allow adequate time for the RTV to set and dry before re-installing the oil pan.

RTV vs. anaerobic sealant

When it comes to rigid flanges, anaerobic sealants are the best choice. They are designed to achieve optimum stiffness between two parts, minimise movement between them, and transmit forces from one to another. Anaerobic sealants are ideal for rigid bolted joints because they offer metal-to-metal contact, ensure correct bolt tension, add structural strength, offer high-pressure resistance, and have an extensive on-part life when exposed to air.

On the other hand, RTV (Room Temperature Vulcanising) elastomers are better suited for flexible flanges. They are commonly used to seal gearbox covers, timing chain covers, stamped sheet steel parts, thin-walled metal castings, and oil pans. Flexible flanges are typically used to cover openings in housings, seal liquids inside components, or protect them from external contamination.

One key difference between the two types of sealants is their on-part life. Anaerobic sealants remain liquid on parts as long as they are exposed to oxygen, while RTV elastomers cure into rubbery solids by reacting with moisture from the environment. This gives RTV elastomers a much shorter on-part life compared to anaerobic sealants.

In terms of application, anaerobic sealants require metal as one of the surfaces, while RTV silicones do not have this requirement for polymerisation. Anaerobic sealants will not start to cure unless they are confined between two surfaces, excluding the oxygen in the air. This gives workers flexibility during the assembly process. In contrast, RTV silicones start to cure immediately upon dispensing, requiring the assembly to be completed within 5-10 minutes to avoid issues with partial curing.

For temperature resistance, both types of sealants can be used up to 150 °C. However, some grades of anaerobic adhesives can withstand temperatures up to 200 °C. Above 150 °C and up to 365 °C, only RTV silicones will work. If the gap between the mating surfaces is 0.25 mm or below, either anaerobic or silicone sealants can be used, but for larger gaps, only silicone is recommended.

In terms of bonding strength, anaerobic sealants offer higher bonding strengths of 4-9 N/mm2, making them suitable for applications that require resistance to seepage. RTV silicones, on the other hand, provide bonding strengths up to 2.5 N/mm2, which is sufficient for most applications.

Permatex Ultra Black

To use Permatex Ultra Black, first clean and dry all surfaces with a residue-free solvent, such as Permatex Brake & Parts Cleaner. Cut the nozzle to the desired bead size—gaskets are best formed using a 1/16" to 1/4" bead. Apply a continuous and even bead of silicone to one surface, surrounding all bolt holes. Assemble parts immediately, finger-tightening bolts until the material begins to squeeze out around the flange. Allow to dry for one hour, then retighten by 1/4 to 1/2 turn. Replace the cap after use and clean tools with a non-flammable cleaning fluid.

Loctite 5900

Some people have used Loctite 5900 as an engine sealant for Porsches, and it has been recommended for use on Chevy LS engines. It has received positive reviews for its quality and ability to prevent oil pan leaks.

Using RTV on the entire pan surface

RTV, or room-temperature vulcanizing rubber, is a type of sealant commonly used in automotive applications. When it comes to using RTV on the entire pan surface, there are a few things to consider. Some people suggest using RTV on the entire pan surface to ensure a better seal and prevent leaks. This involves applying a bead of RTV around the pan, inside the bolt holes, and then placing the pan and tightening the bolts. This method can provide an extra layer of protection against leaks, especially at the corners of the pan, which are common leak points.

However, others argue that using RTV on the entire pan surface is unnecessary and may even be detrimental. They suggest that the oil pan gasket is usually sufficient to seal the pan, and adding RTV can be a waste. Excess RTV on the inside of the pan can break off and get sucked into the oil pickup, causing potential issues. Therefore, it is recommended to apply RTV only at the corners of the pan and the front and rear cover seams, which are the most common leak points.

It is important to follow the manufacturer's instructions and recommendations when using RTV. Different types of RTV are available, such as black, blue, or grey, and it is essential to use the correct type for the specific application. The surface preparation is also critical, ensuring that the pan and mating surface are clean, dry, and free of any oil or debris. Proper torque specifications and sequences should be followed when tightening the bolts to ensure an even seal.

When deciding whether to use RTV on the entire pan surface, it is essential to weigh the benefits of added protection against the potential risks of excess RTV breaking off. Proper surface preparation, using the correct type of RTV, and following the manufacturer's instructions are crucial to achieving a successful seal and preventing leaks.

Application techniques

RTV is a type of sealant that can be used on oil pans to prevent leaks. When reinstalling an oil pan, it is important to follow the correct application techniques to ensure a successful gasket installation and to avoid leaks. Here are some detailed instructions and tips for applying RTV to an oil pan:

Surface Preparation

Before applying RTV, it is crucial to clean and dry the surfaces of both the oil pan and the engine block. Remove any old RTV or gasket material, oil, and dirt from the surfaces. You can use brake cleaner to ensure that the surfaces are free of contaminants. It is also recommended to check the oil pan flange to ensure it is flat.

RTV Selection

There are different types and brands of RTV available, such as black, blue, grey, red, or copper RTV. Choose a RTV that is suitable for your specific application and follow the manufacturer's instructions for proper use. Some commonly used brands include Permatex, Loctite, and ThreeBond.

RTV Application

Apply a small amount of RTV to the corners of the oil pan gasket and/or stepped casting areas that have gaps. You can also apply RTV to the corners or stepped areas on the engine block. Do not apply RTV to the entire gasket, as this can cause over-compression and damage to the gasket. Remember that a little RTV goes a long way, and it will flow into the joint and gasket when torqued into place.

Timing of Installation

It is recommended to install the oil pan within five minutes of applying the RTV. Once the oil pan is installed and torqued to the specified values, allow the RTV to set and dry completely before continuing with the job. RTV typically needs about 24 hours to fully cure.

Use of Gasket

While RTV can be used by itself, some people prefer to use it in combination with a gasket to ensure a better seal. If using a gasket, you can apply RTV to both sides of the gasket before placing it on the oil pan. After torquing the bolts, wipe off any excess RTV from the edges.

Bolt Torque and Sequence

Proper bolt torque and sequence are crucial for a successful oil pan installation. Follow the recommended torque values and sequence provided by the manufacturer or in the repair manual. Re-torque the bolts after 24 hours to ensure they are tightened to the correct specifications.

Additional Tips

• Always follow the manufacturer's recommendations for the proper use of RTV.
• Uncured RTV can act as a lubricant, so be careful not to apply too much, as it may cause the gasket to slip out of place.
• Some RTVs require a specific cure time, so refer to the directions on the RTV for application instructions, bead width, and setup time.
• If you need to remove the oil pan in the future, using a gasket without RTV can make the process cleaner and easier.

Frequently asked questions