loctite 245

Loctite 245

Color:Blue
Fixture time:12.0 – 240.0 min.
Key characteristics:Thixotropic
Recommended for use with:Metal: brass, Metal: steel, Metal: steel – stainless steel
Viscosity, Brookfield – RVT, @ 25.0 °C Spindle 5, speed 2.5 rpm:5600.0 – 10000.0 mPa·s (cP)
Viscosity, EN 12092 – MV, @ 25.0 °C Shear Rate 129 s⁻¹:17500.0 – 52500.0 mPa·s (cP)

Overview

Loctite 245 is a blue, medium-strength anaerobic threadlocker designed to lock and seal metal fasteners in the medium size range. It cures in the absence of air between close-fitting metal surfaces, forming a tough, thermoset plastic that fills the thread gap and resists loosening.

Once cured, Loctite 245:

  • Reduces loosening from shock, impact and continuous vibration

  • Seals the helix against micro-leaks of fluids and gases

  • Helps protect engaged threads from rust, galling and fretting corrosion

It’s a versatile balance between reliable locking and straightforward disassembly with normal hand tools during maintenance.

Why choose Loctite 245?

1) Medium strength – secure, yet serviceable
Loctite 245 is formulated to deliver medium breakaway torque. Fasteners stay locked in service, but can still be removed using standard tools, making it ideal for pumps, motors, gearboxes and general machinery that will be opened periodically.

2) Thixotropic “no-run” rheology
The adhesive is thixotropic, meaning it behaves like a gel that resists flow at rest but spreads under shear. It doesn’t drip on vertical bolts, doesn’t migrate across surfaces, and stays concentrated in the threads where it is needed.

3) Designed for medium-size fasteners
Loctite 245 is particularly suited to typical machine bolt sizes (for example in the M6–M18 range, depending on design), covering most brackets, covers, housings and mounting points in industrial and automotive equipment.

4) Locks and seals in one simple step
By filling the engagement between male and female threads, 245 both locks the fastener and lightly seals the interface, reducing leak paths and improving long-term corrosion resistance without separate sealants or mechanical lock devices in many cases.

5) One-part, easy to handle
Supplied as a single-component blue liquid in a squeeze bottle, Loctite 245 needs no mixing or special equipment. Blue color clearly distinguishes it from low-strength purple and high-strength red grades in the workshop.

Typical Applications

Industrial machinery & equipment

  • Mounting bolts on pumps, motors, gearboxes and conveyors

  • Housing screws and cover bolts that see vibration and shock

  • Medium-size fasteners on mixers, presses and handling equipment

Automotive & power equipment

  • Fasteners on engines, transmissions and auxiliaries that require regular service

  • Brackets, covers and fixtures in vehicles and small engines

General maintenance and repair

  • Plant maintenance fasteners where spring washers and split washers are not enough

  • Medium-size screws in equipment cabinets, guards and supports

Loctite 245 is intended for metal-to-metal threads and is not recommended for plastics or for use in pure oxygen or strong oxidizer systems.

How to Use Loctite 245

Step 1 – Surface preparation

  • Remove loose rust, dust and old threadlocker from threads.

  • Wipe away heavy grease, thick oil and visible anti-seize.

  • Light “as-received” oil films may be tolerated, but cleaner metal gives more consistent and higher strength.

Step 2 – Apply the product

  • Shake the bottle briefly.

  • Apply a continuous bead of Loctite 245 to the male threads, covering the full engagement length.

  • For blind holes, dispense a small amount into the female thread so adhesive is pushed through the joint during assembly.

Step 3 – Assemble and tighten

  • Assemble the joint and torque the fastener to the specified value.

  • Avoid repeatedly backing off and retightening once the adhesive has begun to fixture.

Step 4 – Cure and return to service

  • Allow the assembly to sit undisturbed until handling strength is reached.

  • For maximum performance, allow up to 24 hours at room temperature before exposing the joint to full load, pressure or vibration.

Step 5 – Disassembly

  • Loosen the fastener with standard hand tools (wrench, socket, hex key).

  • On larger bolts or those that have been in service for a long time, additional leverage or an impact tool can help break the bond, but heat is usually not required for Loctite 245.

Safety & Handling (Summary)

Typical safety profile for medium-strength anaerobic threadlockers like Loctite 245:

  • May cause skin and eye irritation on contact

  • Repeated or prolonged exposure may lead to skin sensitization in some individuals

  • Vapours or mists in confined spaces can cause mild respiratory irritation

  • Uncured product may be harmful to aquatic life if released uncontrolled

Basic precautions:

  • Use only in well-ventilated areas.

  • Avoid contact with skin and eyes; wear safety glasses and suitable protective gloves.

  • Wash hands thoroughly after handling and before eating or drinking.

  • Do not dispose of uncured product into drains or natural waterways.

  • Store in the original, tightly closed container in a cool, dry place away from heat and direct sunlight.

Always follow the most recent Safety Data Sheet (SDS) for Loctite 245 in your region.

FAQs

Q1: How is Loctite 245 different from Loctite 242 or 243?
Loctite 245, 242 and 243 are all medium-strength blue threadlockers. Loctite 245 focuses on a thixotropic, “no-run” behavior for medium-size fasteners, while 243 is optimized for oil tolerance. In practice, 245 is often chosen when you want a stable, gel-like grade for production assemblies.

Q2: When should I choose Loctite 245 instead of a high-strength grade like 271 or 270?
Select Loctite 245 when you need strong locking but easy serviceability: pumps, motors, covers, brackets and joints that will be removed occasionally. Choose high-strength reds when joints are intended to be permanent and removal, if ever required, can involve heat and very high torque.

Q3: Can Loctite 245 be used on stainless steel or plated hardware?
Yes. Loctite 245 is suitable for many common metals, including carbon steel, stainless steel and plated fasteners. On passive metals (like stainless and heavily plated parts), cure can be slower; allow extra time before fully loading the joint or consult Henkel for activator recommendations.

Q4: Is Loctite 245 oil-tolerant?
Loctite 245 can handle light oil residues, but heavy coatings of oil, grease, cutting fluid or anti-seize should be removed for best performance. If curing on oily parts is a major concern, an explicitly oil-tolerant grade such as Loctite 243 may be preferred.

Q5: Is Loctite 245 suitable for very small screws?
It will bond small screws, but as a medium-strength product it may provide too much torque for very tiny fasteners or soft alloys. For delicate screws and lightweight assemblies, a low-strength purple grade like Loctite 222/222MS is usually safer.

Q6: Can I use Loctite 245 on plastic threads or mixed metal/plastic joints?
No. Anaerobic threadlockers like Loctite 245 are formulated for metal-to-metal threads and can cause stress cracking in certain plastics. They also do not cure properly on non-metallic surfaces. For plastic or mixed joints, choose a plastic-compatible adhesive.

Q7: Does Loctite 245 also seal against fluid leaks?
Yes. By filling the gap between male and female threads, Loctite 245 locks and lightly seals at the same time, helping to prevent leakage through the thread helix and protecting against corrosion. It is not a replacement for flange gaskets, but it is very effective for sealing through-thread leak paths.

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