Best in 7 days
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Ships within 48 hours · Estimated delivery Oct 4 - Oct 9
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Description
Forespar MF 842 Vented Loop - 3/4" [903001]MF 842 Vented Loop 3 4" Installing one of our vented loops will ensure that fluids will not siphon from tank to tank. Vented loops are commonly used in the marine toilet system and engine cooling system. The simple valve system incorporated in the top of the loop allows air to enter the line when not in use, yet effectively seals as water or other fluid passes through. Molded in Marelon, neither vent nor loop will corrode. The duckbill one way valve
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- 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
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Best in 7 days
Best in 7 days
4.1 ★★★★★
Based on 1572 reviews
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Product Reviews
★★★★★ 5
OEM is always the answer
No reason not to go OEM for this! Came with every possible gasket and seal I could need. Specifically for my Alpha One Gen 1 it took maybe 25-30 min to completely install.
While you’re there check the base plate for wear and the other surrounding items like your water tube. Rather keep the lower unit off for an extra day to get another part than a catastrophic failure.
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Reviewed in the United States on September 9, 2025
★★★★★ 5
Husbands things
My husband bought this. I don’t know much about it but he has zero complaints. He bought it for a boat. He has fixed up 2 boats, sold one & we kept the other. So he apparently knows what to buy & how to use it.
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Reviewed in the United States on November 6, 2025
★★★★★ 4
Amazon is easy and fast . No problems the oarts was exactly as described.
liked that everything was in one bag . and could make sure everything was changed .
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Reviewed in the United States on August 3, 2020
★★★★★ 5
Stay cool
Just what I needed, super fast shipping
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Reviewed in the United States on October 19, 2025
★★★★★ 5
Outboard is Cooling
The repair kit arrived on time as scheduled. The kit contained everything needed to replace the Mercury 175 OptiMax impeller. The engine is cooling now and we are back on the water without issue. Easy replacement.
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Reviewed in the United States on July 5, 2023
