---
title: "S3213 Fuel Water Separator Filter — $43K/yr Amazon US Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/us/automotive/s3213-fuel-water-separator-filter"
last_updated: "2026-08-09T14:03:24.041Z"
locale: en
meta:
description: "Niche score 60/100 · $43K/yr market · 21K searches/yr. A failed launch gate (market size, growth, or returns) keeps it on the watch list. Data updated Jul 2026."
"og:description": "Niche score 60/100 · $43K/yr market · 21K searches/yr. A failed launch gate (market size, growth, or returns) keeps it on the watch list. Data updated Jul 2026."
"og:title": "S3213 Fuel Water Separator Filter — $43K/yr Amazon US Niche (2026) - Flapen"
---
# **s3213 fuel water separator filter**
**Worth a look**
Shows demand growing +124.8% this quarter, but a failed launch gate (market size, growth, or returns) keeps it on the watch list.
Market size 11Growth 95Conversion 78Competition 41Returns 87Price range 89Avg price 95Brand share 56Review moat 95Quality gap 22
**Growth**
**Incredible****+124.8%**
90-day search growth — must beat 0% to launch
**Review moat**
**Great****103.9**
avg incumbent reviews — the moat a new listing must climb
**Avg price**
**Incredible****$26.31**
avg listing price — sweet spot $15–$100
**Price range**
**Great****$10.60–$70.53**
cheapest to priciest tracked listing — scored on the share inside $15–$100
**Returns**
**Great****1.4%**
return rate — above 5% kills the launch gate
**Conversion**
**Great****7.6%**
search→purchase rate — share of searches ending in a sale
**Brand share**
**Good****71%**
top-5 brand share — brands hold most of the demand
**Competition**
**Okay****60%**
top-5 click share — leaders hold, buyers still browse
**Quality gap**
**Bad****4.7★**
avg incumbent rating — lower means beatable quality
**Market size**
**Bad****$43K**
$43K/yr · 21K searches
**Signals**[** Trending**](https://flapen.com/research/niches?market=us&signal=trending "Search growth > 100% (90d)") [** Low Review Barrier**](https://flapen.com/research/niches?market=us&signal=low_review_barrier "Top brand's reviews < 500")
According to Flapen's Amazon United States niche tracking, s3213 fuel water separator filter is a $43K/yr Amazon United States market (21K searches/yr). The top 5 brands hold 71% of demand. Demand peaks in Apr–May–Jun–Jul. Verdict: Worth a look — 60/100.
Data updated Jul 9, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **s3213 fuel water separator filter market data**
- **Units sold / yr**
- **3K–3K**
- avg 100–250/product
- **Revenue / yr**
- **$66K–$79K**
- units × avg price
- **Conversion rate**
- **7.6%**
- **Avg BSR**
- **#907**
- **Page quality**
- **0%**
- **Prime**
- **90%**
- **Sponsored**
- **85%**
- **Out of stock**
- **0.0%**
- **Avg brand age**
- **51 months**
- **Avg seller age**
- **208 days**
## **Competition & brand share**
The top 5 products take 60% of clicks — established leaders, but buyers still shop beyond them.
**Brands**
**15 **▼falling
**Sellers**
**38**
**Top-5 brand share**
**71%**
Top 20: 100%
**Top-5 click share**
**60%**
Top 20: 100%
**Open market**
**23%**
- ATRACYPART24% - AULDAY16% - Vkinman13% - TRSCJXN10% - DZFST.FI9% - SEGULER5%
## **Demand & seasonality**
Weekly Amazon search volume, last 104 weeks — +124.8% search growth over the last 90 days.
800600Spike '24Spike '25Holiday '25Spike '26 seasonSepDecMarJunAugNovMarMay
Peak months: Apr, May, Jun, Jul · busiest ÷ quietest = 3.9×
[**Open Trend **](https://flapen.com/research/us/automotive/s3213-fuel-water-separator-filter/trend)
## **Top s3213 fuel water separator filter search terms**
- **s3213 fuel water separator**10K/yr+220.1%8.1% conv. - **s3213**4K/yr+65.4%11.3% conv. - **racor s3213**3K/yr+78.3%7.9% conv. - **s3213 fuel filter**4K/yr+46.6%12.8% conv. [**All search terms **](https://flapen.com/research/us/automotive/s3213-fuel-water-separator-filter/search-terms)
## **Top s3213 fuel water separator filter products on Amazon**
Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.
0%10%$4K20%$9K30%$13K40%$17K1101001K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)
All 20 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**S3213 Fuel Filter Marine Water Separator with Clear Bowl AssemblyReplacement For Marine Outboard Motor Mercury Replaces# 35-60494-1 18-7932-1 18-17928 35-809097**ATRACYPART**$20.13**4.6★168 rev](https://www.amazon.com/dp/B0B9M5VQYN) [2**Vkinman S3213 Fuel Filter Marine Fuel Water Separator Replacement for Marine Outboard Motor Compatible with Mercury Replaces 35-60494-1 B32013 18-7932-1 (2Pcs)**Vkinman**$22.28**4.3★38 rev](https://www.amazon.com/dp/B0CYZ792KV) [3**DZFST.FI S3213 Fuel Water Separator Filter Compatible with Marine Outboard Motor Mercury Yamaha Racor Sierra Engine Boat 10 Micron Replaces# 35-60494-1 S3213 18-7932-1 18-17928 35-809097**DZFST.FI**$19.20**4.5★108 rev](https://www.amazon.com/dp/B0C497KJPF) [4**S3213 Fuel Water Separator Marine Kit Compatible with Yamaha and for Mercury Marine Outboard Motor with 3/8 Barb x 1/4 NPT Brass Fittings Replaces B32013 35-60494-1 18-7932-1 18-17928 35-809097**TRSCJXN**$24.32**4.6★51 rev](https://www.amazon.com/dp/B0FQTNXPWP) [5**S3213 Fuel Filter Marine Fuel Water Separator With Clear Bowl Replacement for Marine Outboard Motor Replaces# 35-60494-1 S3213 18-7932-1 18-17928 35-809097**AULDAY**$18.92**4.5★225 rev](https://www.amazon.com/dp/B097TJLPSR)
**~~View all top sellers →~~**
### **Newest**
by launch date
[**S3213 Marine Fuel Water Separator Filter Assembly with Clear Bowl 3/8 Inch NPT Port Compatible with Yamaha and for Mercury Outboard Motors Replaces 35-60494-1 18-7932-1 18-17928 35-809097**TRSCJXN**$17.32**1 rev4w ago](https://www.amazon.com/dp/B0GZT26PWP) [**S3213 Fuel Water Separator Filter with Clear Bowl: 10 Micron Marine Fuel Filter Compatible with Yamaha/Mercury/Suzuki/Racor. Replaces 35-60494-1 18-7932-1. Installation Kit Screws Fittings & Clamps**SURGLA**$26.05**25 rev5mo ago](https://www.amazon.com/dp/B0GKG8MBG2) [**S3213 Fuel Water Separator Marine Kit Compatible with Yamaha and for Mercury Marine Outboard Motor with 3/8 Barb x 1/4 NPT Brass Fittings Replaces B32013 35-60494-1 18-7932-1 18-17928 35-809097**TRSCJXN**$24.32**51 rev8mo ago](https://www.amazon.com/dp/B0FQTNXPWP) [**2PCS S3213 Fuel Filter Marine Fuel Water Separator Replacement for Marine Outboard Motor Replaces# 35-60494-1 S3213 18-7932-1 18-17928 35-809097**AULDAY**$22.03**11 rev11mo ago](https://www.amazon.com/dp/B0FM1VCBFJ) [**2PCS S3213 Fuel Filter Marine Fuel Water Separator With Clear Bowl Replacement for Marine Outboard Motor Replaces# 35-60494-1 S3213 18-7932-1 18-17928 35-809097**AULDAY**$36.97**15 rev11mo ago](https://www.amazon.com/dp/B0FM2S4D39)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[**S3213 Marine Fuel Water Separator Filter Assembly with Clear Bowl 3/8 Inch NPT Port Compatible with Yamaha and for Mercury Outboard Motors Replaces 35-60494-1 18-7932-1 18-17928 35-809097**TRSCJXN**$17.32**5.0★**▲ 177%**](https://www.amazon.com/dp/B0GZT26PWP) [**S3213 Fuel Water Separator Filter with Clear Bowl: 10 Micron Marine Fuel Filter Compatible with Yamaha/Mercury/Suzuki/Racor. Replaces 35-60494-1 18-7932-1. Installation Kit Screws Fittings & Clamps**SURGLA**$26.05**4.3★**▲ 155%**](https://www.amazon.com/dp/B0GKG8MBG2) [**CADUFUELLY S3213 Fuel Filter Marine Oil-water Separator Oil-water Separator for Mercury Replaces 35-60494-1 S3213 18-7932-1 18-17928 35-809097 (Fuel Filter Water Separator)**CADUFUELLY**$10.60**5.0★**▲ 133%**](https://www.amazon.com/dp/B0BTS51K8C) [**S3213 18-7932-1 Fuel Filter Marine Water Separator with Clear Bowl Assembly Compatible with Marine Outboard Motor Replaces 35-60494-1 18-17928 35-809097**ZELYVER**$17.27**5.0★**▲ 41%**](https://www.amazon.com/dp/B0DP4FJMF7) [**2PCS S3213 Fuel Filter Marine Fuel Water Separator Replacement for Marine Outboard Motor Replaces# 35-60494-1 S3213 18-7932-1 18-17928 35-809097**AULDAY**$22.03**4.4★**▲ 24%**](https://www.amazon.com/dp/B0FM1VCBFJ)
**~~View all trending →~~**
## **What buyers say about s3213 fuel water separator filter**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Quality-Overall**21%
*“The build quality feels solid and well-made, and installation was simple and straightforward”*
**Value For Money**17%
*“Great value for price”*
**Advertised Vs Actual Product**11%
*“As Advertised”*
**Filtration**8%
*“Good filter system”*
**Assembly/Installation**8%
*“My son was excited to help watch the installation”*
**Leak-Proof**8%
*“does not leak”*
**Size-Overall**7%
*“Good fit”*
**Ease Of Use**4%
*“easy solution”*
**Fuel Efficiency**3%
*“the product was easy to modify to fit my fuel system”*
**Maintenance And Repair**2%
*“Cost effective preventative maintenance”*
### **What buyers complain about **
**Leak-Proof**23%
*“Fuel leaking”*
**Filtration**19%
*“Filter was not the correct one”*
**Quality-Overall**8%
*“were kind of cheap”*
**Assembly/Installation**5%
*“havent installed it”*
**Metal Quality**5%
*“Metal shavings”*
**Defective Material/Parts**5%
*“The plastic piece on the bottom would not screw on tightly”*
**Water Resistance**2%
*“My boat has a chronic issue with water getting into the fuel”*
**Functionality-Overall**2%
*“within 5 minutes the same issue”*
**Rubber Quality**2%
*“The rubber O-rings dont work”*
**Measurement/Reading Accuracy**2%
*“Cross reference numbers are incorrect”*
### **Top return reasons **
**Size-Overall**45%
**Compatibility-Overall**12%
**Filtration**11%
**Defective Material/Parts**7%
**Advertised Vs Actual Product**5%
**Leak-Proof**3%
**Functionality-Overall**3%
**Mounting**2%
**Assembly/Installation**2%
**Value For Money**2%
## **Common questions**
- **Is s3213 fuel water separator filter profitable to sell on Amazon United States?**
- The niche generates $43K/yr across 20 tracked products. 2 of 5 products launched in the last 360 days are still selling. 90-day search growth is +124.8%. Flapen's verdict: Worth a look (60/100).
- **How competitive is the s3213 fuel water separator filter niche?**
- 15 brands and 38 sellers compete. The top 5 products take 60% of clicks and top 5 brands hold 71% of demand.
- **What do buyers complain about in s3213 fuel water separator filter?**
- Top complaints mined from reviews: Leak-Proof, Filtration, Quality-Overall. The return rate is 1.4%.
- **When does demand for s3213 fuel water separator filter peak?**
- Demand peaks in Apr–May–Jun–Jul; the busiest month runs 3.9× the quietest.
- **What does it cost to enter the s3213 fuel water separator filter niche?**
- Listings span $10.60–$70.53; the average listing price is $26.31 (sweet spot $15–$100). The average incumbent carries 104 reviews — the moat a new listing must climb.
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