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Fuel Filter Tool for Mercury - Mallory
Summer Sale Price: $5.94 (Out of stock)
Save: $1.71
(22% Off $7.65)
Part # 9-79814 ValueShip™ Eligible
Fuel Tester for Mercury - Mallory
Summer Sale Price: $6.79
Save: $1.60
(19% Off $8.39)
Part # 9-79816
SHIPS TOMORROW!* if ordered in 22 hrs 35 mins.
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Fuel Filter Tool for Mercury - Mallory
Fits: Mercury Optimax and Verado

Replaces: Mercury
  • 91-896661
Fuel Tester for Mercury - Mallory
Replaces: Mercury
  • 91-879172T28

Video Transcript

This is Henry Carrier from Mallory Marine. Today we are going to talk about common problems associated with ethanol in gasoline and how to test for them.

Ethanol blended fuels are responsible for thousands of dollars in engine damage and higher maintenance cost each year. Even though the ethanol content is supposed to be legally regulated at a maximum of 10%, it is not uncommon to find fuel that exceeds this limit. Due to the way ethanol was added to the fuel, transportation methods and storage conditions may cause higher ethanol concentrations to be commonly found. We have received reports of dealers finding the excess of 20% in some areas.

This leads to chronic fuel related engine problems. Some common issues and problems associated with excess ethanol in fuel include: water in gas tank; phase separation, vapor lock, stalling, hesitation, and hard starting, corrosion/rusting of all fuel system components; premature failure of fuel pump and other components; clogging/plugging of filters, fuel injectors and carbonator passages all leading to engine damage. Marine engine manufacturers do not recommend fuel with more than 10% ethanol content. And more importantly will not warranty engine failures caused by excess ethanol in fuel.

Mallory Marines' ethanol tester can help you avoid costly ethanol fuel problems. And today we are going to show you how to use it. Remember to always follow safety precautions when handling fuel in the tester.

Fill with tap water to the waterline. Fill with gas to the neck. Put lid on and shake vigorously. Stay in vertical with cap on. Let it settle until a well-defined separation occurs. This can take from 2 to 10 minutes. Locate the gas-water separation line and read scale for percentage of alcohol. That is how simple it is to use the Mallory Marine ethanol tester.

Help avoid costly repairs by using the Mallory Marine fuel tester. It is easy to use, reusable, and it gives fast results in as little as two minutes. For more information about Mallory Marine products, please visit
Average Customer Review for Fuel Filter Tool for Mercury - Mallory
Full StarFull StarFull StarFull StarEmpty Star Based On 5 Reviews | Write Review
Full StarFull StarFull StarFull StarFull Starfuel filter removal tool
by Kurt from Kenosha, Wisconsin on May 20, 2015
good product...does what it should ...removes filter without damaging the fins on the fuel filter! easy and fast ! everybody should have one!
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Full StarEmpty StarEmpty StarEmpty StarEmpty StarNotification of Back Order
by Daniel from Panama City, Florida on August 23, 2013
Product was put on back order and I was not notified. After several days past the delivery date I called and was informed the part was on back order. A simple e-mail would have been nice and then I could have canceled the order since I have now taken it to the shop for repair. I do not plan to order any more items from iboats.
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Full StarFull StarFull StarFull StarFull StarThe only way to remove fuel filter
by Thomas from Renfrew, Ontario on May 08, 2013
No more mangling or struggling to remove filter, a must have.
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Full StarFull StarFull StarFull StarFull Starreview
by Daniel from Baldwinsville, New York on November 12, 2012
(1 of 1 people found this review helpful)
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Full StarFull StarFull StarFull StarFull StarJust what i needed
by Michel from Val-Des-Monts, Quebec on March 26, 2012
Fast shipping...everything in order! Yeah! :)
(2 of 2 people found this review helpful)
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