SKU: 65261907991

Thermostat Repair Service Kit – Fits Mercury/MerCruiser 4.3L 5.0L 5.7L 7.4L V6 V8 SternDrive Motors (Replaces 807252Q4, 807252T4, 807252T7, 8M0089715)

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Description

Thermostat Repair Service Kit – Fits Mercury/MerCruiser 4.3L 5.0L 5.7L 7.4L V6 V8 SternDrive Motors (Replaces 807252Q4, 807252T4, 807252T7, 8M0089715)Thermostat Repair Service Kit Fits Mercury MerCruiser 4. 3L, 5. 0L, 5. 7L, 7. 4L V6 & V8 This thermostat repair service kit is designed for a wide range of Mercury MerCruiser V6 and V8 gasoline sterndrive engines (262 454 CID) manufactured between 1983 and 2016 with standard cooling systems. It maintains the correct engine operating temperature of 140F (60C) to ensure optimal performance, fuel efficiency, and engine longevity. This kit is a direct

Thermostat Repair Service Kit – Fits Mercury/MerCruiser 4.3L, 5.0L, 5.7L, 7.4L V6 & V8

This thermostat repair service kit is designed for a wide range of Mercury/MerCruiser V6 and V8 gasoline sterndrive engines (262-454 CID) manufactured between 1983 and 2016 with standard cooling systems. It maintains the correct engine operating temperature of 140°F (60°C) to ensure optimal performance, fuel efficiency, and engine longevity.

This kit is a direct replacement for Mercury/MerCruiser part numbers 807252Q4, 807252T4, 807252T7, and 8M0089715.

  • Operating Temperature: Opens at a nominal 140°F (60°C).
  • Engine Compatibility: Fits various GM-based V6 and V8 engines from 1983–2016.
  • Complete Solution: Includes the thermostat and all necessary gaskets and seals for a full replacement.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Brand Part Number
Mercury/MerCruiser 807252Q4
Mercury/MerCruiser 807252T4
Mercury/MerCruiser 807252T7
Mercury/MerCruiser 8M0089715
Sierra 18-3668
GLM 13390
Mallory 9-43150

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Brand Model Rated HP Stroke Years OEM Part No. Notes
MerCruiser 4.3L V6 175/185/205 175-205 4-Stroke 1985–1987 807252Q4 Model years 0A331455-0B775129
MerCruiser 4.3L V6 175-205 4-Stroke 1987–1995 807252Q4 Model years 0B773243-0F601126
MerCruiser 5.0L & 5.7L Small Block 200-260 4-Stroke 1983–1984 807252Q4 Model years 6218462-6899057
MerCruiser 5.0L 200-230 4-Stroke 1988–1995 807252Q4 Model years 0B774445-0F600999
MerCruiser 5.0LX 230 4-Stroke 1988–1995 807252Q4 Model years 5907058-0F600999
MerCruiser 5.7L/5.7MIE/SKI 260-350 4-Stroke 1988–1995 807252Q4 Model years 0B773305-0F600999
MerCruiser 7.4L/MIE 330-340 4-Stroke 1988–1994 807252Q4 Model years 0B771113-0F351999
MerCruiser GM V6 & V8 Various 4-Stroke 1983–2016 807252Q4 Standard cooling systems only

Technical Specifications

Specification Value
Product Type Thermostat Kit
Installation Standard Cooling System
Operating Temperature 140°F (60°C) nominal opening
Housing Material Brass
Housing Color Silver/Metallic
Weight 0.11 kg (0.25 lb)
Warranty 1-year (aftermarket)
Other Technical Attributes Not for use with high-performance engines

Package Contents

This comprehensive kit includes the following components:

  • 1 x Thermostat (8M6002714 / 59137)
  • 1 x O-Ring (25-30224)
  • 1 x Gasket, Thermostat Housing Cover (27-33179-2)
  • 1 x Gasket, Thermostat Cover (27-41812)
  • 1 x Gasket, Thermostat Housing (27-47510)
  • 1 x Gasket, Lower Housing (27-530451 / 27-48818-1)
  • 1 x Gasket (27-33918)

Installation Guide

Follow these general steps for installation. Always consult your engine’s service manual for detailed instructions and torque specifications.

  1. Safety First: Ensure the engine is completely cool before starting.
  2. Drain Coolant: Drain the engine coolant to a level below the thermostat housing.
  3. Access Housing: Locate and remove the bolts securing the thermostat housing cover.
  4. Remove Old Parts: Take out the old thermostat and gaskets. Note the orientation of the thermostat.
  5. Clean Surfaces: Thoroughly clean the mating surfaces of the housing and cover, removing any old gasket material or sealant.
  6. Install New Parts: Place the new thermostat and gaskets into the housing in the correct orientation.
  7. Reassemble: Reattach the housing cover and tighten the bolts to the manufacturer's specified torque.
  8. Refill System: Refill the cooling system with the appropriate coolant.
  9. Final Check: Start the engine, check for any leaks, and monitor the temperature gauge to ensure it reaches and maintains the correct operating temperature.

Troubleshooting & FAQ

Q: How do I confirm this thermostat kit will fit my specific engine?
A: The best way to ensure fitment is to check the part number on your original thermostat. You can also use our Compatible Engine Models table to find your model, year, and serial number range. If you are still unsure, please contact our support team with your engine details.

Q: What are the signs of a failing thermostat?
A: Common symptoms include engine overheating, the engine not reaching normal operating temperature (running too cool), erratic temperature gauge readings, and potential coolant leaks around the thermostat housing.

Q: How often should I replace my engine's thermostat?
A: Thermostats are a critical maintenance item. It is recommended to replace them as part of a major cooling system service every 3-5 years, or immediately if you notice any signs of failure. Proactive replacement can prevent engine damage from overheating.

Q: Why is the 140°F temperature important for my marine engine?
A: This 140°F thermostat is specified for raw-water cooled engines to prevent salt and mineral buildup that can occur at higher temperatures, which could restrict cooling passages and lead to overheating.

Q: Is this an OEM part or an aftermarket replacement?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

  • Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
  • This product is an aftermarket replacement part and is not an OEM component.
  • Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

  • Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
  • Fast Global Shipping: Free delivery worldwide in 5–15 days.
  • Direct from Manufacturer: Competitive pricing without compromising quality.
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 65261907991

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Katrina Rhodes
Belleville, US
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Nice divider, serves it's purpose well!
Size: 3 Panel 12FT W
This room divider worked out very well for what I needed. I wanted a simple way to create a little more privacy and separation in a larger room without doing anything permanent, and this divider was an easy solution. The panels provide good coverage, and the black color gives it a clean, modern appearance that blends in nicely with different décor styles. Assembly was fairly straightforward, and once set up, the wider feet helped keep the divider stable on the floor. I was especially happy with how flexible the panels are to arrange. You can keep it mostly straight, angle it around furniture, or create a more enclosed private space depending on the layout you need. The material allows light to filter through slightly while still offering a noticeable sense of privacy. I’ve used it for separating a workspace area, but it would also work well in bedrooms, apartments, dorms, studios, or shared living spaces. Another plus is that it can be folded and moved without too much effort when you want to change the setup. Overall, this divider delivers a good balance of functionality, portability, and appearance. It’s a practical option for anyone needing temporary room separation without installing permanent walls or curtains.
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Reviewed in the United States on May 26, 2026
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Jamie K.
Dallas, US
★★★★★ 5
Perfect for Adding Privacy to a Piano Studio
Size: 2 Panel 8FT W, Size: 2 Panel 8FT W
I Ordered the 2 Panel version which is way too big for my needs... that's on me. So keep in mind that the picture shows a fabric made for two panels only being used on one and hence it is not pulled tight; it would pull tight and not be so wrinkly if it was set up properly as two panels. The metal pools that make up the panels seem to be well made, stable, and of good quality. They were very easy to put together and they stand up tall with plenty of height. The appearance of it with the fabric on it isn't as elegant as it could be, but it still looks good enough. The material is plenty solid, not allowing light through it, and thereby making a solid barrier. I am using it to block the view out the studio door when a student is sitting at the piano to avoid distractions from the hallway. It will allow a student to enter the studio with our distracting the student who is at the piano.
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Reviewed in the United States on May 18, 2026
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Just Me
Houston, US
★★★★★ 5
Room Divider That Gives Instant “This Is a Separate Space Now” Energy
Size: 3 Panel 12FT W
The Siebwin 3 Panel Folding Privacy Screen is surprisingly effective at changing the feel of a room without requiring construction, commitment, or somebody yelling about load bearing walls. The 12 foot width gives a substantial amount of coverage, making it useful for creating privacy, dividing open areas, blocking visual clutter, or setting up temporary sections within larger rooms. This saved us a ton of time and money in our new studio and enabled us to create a kitchen and office in one room. The wider feet make a huge difference because flimsy room dividers that collapse every time someone exhales too aggressively are deeply annoying. This one feels more stable and grounded once positioned. The folding design makes it easy to move around or adjust depending on the space, and it folds down relatively compactly when not in use. It is basically the introvert curtain wall of dreams. The material has a clean, neutral look that blends well into different room styles without screaming “temporary office cubicle panic.” It works well for apartments, studios, shared spaces, dressing areas, or simply hiding the mountain of chaos you swear you are going to organize tomorrow. Practical, portable, and refreshingly easy to use without turning setup into a three hour emotional event.
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Reviewed in the United States on May 16, 2026
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Skeetre
Waukegan, US
★★★★★ 4
It's 2 panels holding 1 big privacy screen. Can't use as 2 separate 4' panels, but works great.
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This 2 panel privacy screen works well. Assembly was very straight forward, with easily labeled tubes. My son and I had it together in about 10 minutes, which was probably 3 minutes of me telling him to quit playing around and hand me the parts. It feels very sturdy, not likely to fall over or anything. The material fits well, with the Velcro being very strong. Measurements are all very accurate, with all pieces attaching properly. We have a similar privacy screen at work that we have to try and stretch out because the top and bottom Velcro doesn't fit quite right... this model does not have any issues though. The material is thin and light weight, but solid black so that you can't see anything through or behind it. I definitely think it's a great deal for the money. What I think would have given it 5 stars though, is if you had 2 totally separate 4' panels instead of 2 panels with one big screen. It really wouldn't cost any extra to make it so that the screen was in 2 pieces and you could use it as 2 separate panels instead of having to use it as one big panel. It says 2 panel folding privacy screens, but it's really one big one that folds in the middle.
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Reviewed in the United States on May 25, 2026
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Edith Mastrianni
Fort Morgan, US
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8 panel Room Divider is excellent quality
The GoFlame 8 Panel Room Divider is made with excellent material and the seller of this Divider is totally customer friendly. I highly recommend this company and this Divider if you are shopping for a room divider.
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