Pre filter question for my 2008 Suzuki 70hp

[Shane anthony]

I have read lots of posts here and elsewhere about adding pre filters, seems there are plenty of useful thoughts and opinions. So i guess my question is is this a terrible idea? I’d like to install this setup and change the filter annually. If clearance allows I’d want it in the transom pocket on the side forward the outboard. On the end of my fuel hose tank side I have the priming bulb and a quick disconnect. So it would be tank, bulb and filter down lower then tank and bulb then engine. It’s only a pre filter so 20 microns is fine I’d still be changing the stock filters on the outboard on the regular maintenance schedule. Just looking to add something simple to absorb a little water maybe but not cause issues when I’m out trying to relax. I did read someone’s comment you couldn’t use this filter on electron fuel injection? No mention of what outboard just the injection type. First I’ve heard of this but maybe common knowledge I’m definitely no expert. Thanks in advance for any feedback

[Russ]

I have a fuel injected Suzuki DF70.

Last year I installed a Racor filter similar to what you are describing.
Two reasons. I believe you can't have too much filtration, especially if you ever buy gas from marinas that may have gas sitting over a winter. Second, as a water separator. Marine environments are wet environments. Water will get into your gas and I don't want to have an issue while underway.

I added one similar to this
https://www.westmarine.com/racor-120r-r ... 30445.html

I cut the existing fuel line and installed this between the engine and the squeeze bulb. It's mounted on the wall of the motor well. I'm not sure where the squeeze bulb is supposed to be, but it works fine for me. I did run one tank dry this year and squeezing the bulb after attaching a fresh gas tank worked fine to prime it.

This Spring before launching, I opened the drain and drained a small amount of water in the bowl. So that made me feel good about my decision. The clear glass bowl is reassuring also to see fuel is in there and water is not.


Another important thing when it comes to fuel is to buy Ethanol Free gas. This usually comes in the form of Premium gas. Ethanol attracts water. That's not good for boats. Automobiles can tolerate a bit of water and generally don't let the gas sit for months like our boats.
I do this also for all my small engines (lawnmower gas cans) for the same reason. Ethanol in your can will attract water and water is bad. If your weed wacker or lawn mower won't start in the Spring, good chance there is water in there from ethanol gas.

One caveat was that BEFORE I mounted the filter I tried to remove the filter from the base. That thing was torqued on there so hard I thought I was going to break it. I then reinstalled it with a tad bit of oil on the rubber seal. If you buy one of these, I would test remove the filter while it's on your bench before installing it.

[kmclemore]

I have filters on the fuel lines of both my powerboats, and there’s no way I’d have a powerboat without one. Water, dirt and other contaminants can get into an engine and cause havoc. I change the filter every year at the end of the season. It’s the cheapest insurance you’ll ever buy.

[45Plus+]

I have a Suzuki DF 60 and it came with a RACOR water and fuel filter mounted on transom wall. It may have been installed by PO, not sure so I replaced it this year. I should have just replaced the filter but I bought the complete set along with 3 replacement filter cartridges. Its belts and suspenders for me. Its an easy add on and provides piece of mind particularly here north of the border where non-ethanol gas is increasing hard to find...if you can find it at all. As an aside, I also replaced one of the 12 gal gas tanks with two 6s....the idea being allowing for more complete fuel use and refilling to avoid having it sit too long (and ease of handling of course). This may not matter to people who motor and burn through more gas than those who use the canvas motor. As mentioned above, make sure you separate the top part and the round filter housing before you install it. The manufacturer seem to torque the two together so you can't manually get them apart. I had to put it in my bench vice and gently unscrew the round filter part with a long handled fuel filter wrench....then reattached them hand-tight as specified by the manufacturer. I am glad I did not have to try to get them apart on the transom...I would have likely torn the mounting screws out trying. One other thing, note the fuel hose connector size that comes with the filter - it may or may not be the same as your fuel line (for some reason my Suzuki has a 5/16 line coming out of the engine and the rest of world seems to be set up to use 3/8).

[Starscream]

I have read lots of posts here and elsewhere about adding pre filters, seems there are plenty of useful thoughts and opinions. So i guess my question is is this a terrible idea? I’d like to install this setup and change the filter annually. If clearance allows I’d want it in the transom pocket on the side forward the outboard. On the end of my fuel hose tank side I have the priming bulb and a quick disconnect. So it would be tank, bulb and filter down lower then tank and bulb then engine. It’s only a pre filter so 20 microns is fine I’d still be changing the stock filters on the outboard on the regular maintenance schedule. Just looking to add something simple to absorb a little water maybe but not cause issues when I’m out trying to relax. I did read someone’s comment you couldn’t use this filter on electron fuel injection? No mention of what outboard just the injection type. First I’ve heard of this but maybe common knowledge I’m definitely no expert. Thanks in advance for any feedback

I'm sure you read this thread, but here it is in case: viewtopic.php?t=29150&hilit=fuel&start=30

The was some fine print on the Sierra installation doc that said to install the filter BETWEEN the primer bulb and the motor, but no explanation as to why. At least OverEasy and I don't have it installed that way, with no problems yet.

It's important to source the appropriate teflon tape: fuel-rated tape is colored other than white, maybe orange, yellow or pink, and is specifically rated for gasoline. The white teflon tape used in commercial and residential installations is not the right product.

This is my installation. I like where it is, especially because it's under the dodger and out of the weather while on the water. It's mounted with two aluminum rivnuts and stainless bolts. When I haul out for the winter, I'll add another line from the second discharge terminal that I can use to siphon-drain the tanks, or to refuel the kicker motor from the main tanks.



AFTER I completed my installation and went through the misery of getting the right valves, I found this two-fuel-tanks-adaptor at the Marine Warehouse:
https://www.entrepotmarinemart.com/en/t ... 8-ses52699
It would have been much easier to use this, but on the other hand I'm not sure that it gives the "both" position option as my current setup does.

[OverEasy]

Tight filter on new from the box housings is a thing!
Not just on Racor either….
I think the problem is the lack of grease on the seal surfaces at assembly.
If you put the new filter on dry you’ll probably have the same thing happen when you go to remove it later.
See the same thing on car oil filters when they have been installed dry.

Just apply a thin coating of marine gear lube to the housing seal surface and fuel filter gasket (both sides if you can).

Having a pre filter with a water separator is a no brainer.
Saves having to open the cowling to access the engine filter which is generally on the aft end of the engine down at the base of the cowl where is nearly impossible to reach. Btw: most engine filters don’t have a water drain so you’d have to not only remove the filter (awkwardly at best) but then reinstall a new one… you did lack a spare right? … and you aways have calm waters … and you don’t have bull sharks swimming about just waiting for ‘you to be the snack’…..

The pre filter should match or be a finer micron filtration capability (particle size) than the engine filtration capability, not coarser. You want to catch the problem material before it get to the engine filter.

Never heard of a pre filter restriction for electronic fuel injection… at least not a properly sized one anyway.

To properly size a filter capacity one needs to know your engines maximum fuel flow then at least triple that flow rate value (gallons per minute) to ensure you’ll get adequate fuel to the engine over time… change it at least annually.
Get one with a drainable water separator a viewable collection bowl so you can see and get rid of any water caputured. (The draining collector bowls are often nearly infinitely reusable.)

Best Regards,
Over Easy

[Shane anthony]

I have a Suzuki DF 60 and it came with a RACOR water and fuel filter mounted on transom wall. It may have been installed by PO, not sure so I replaced it this year. I should have just replaced the filter but I bought the complete set along with 3 replacement filter cartridges. Its belts and suspenders for me. Its an easy add on and provides piece of mind particularly here north of the border where non-ethanol gas is increasing hard to find...if you can find it at all. As an aside, I also replaced one of the 12 gal gas tanks with two 6s....the idea being allowing for more complete fuel use and refilling to avoid having it sit too long (and ease of handling of course). This may not matter to people who motor and burn through more gas than those who use the canvas motor. As mentioned above, make sure you separate the top part and the round filter housing before you install it. The manufacturer seem to torque the two together so you can't manually get them apart. I had to put it in my bench vice and gently unscrew the round filter part with a long handled fuel filter wrench....then reattached them hand-tight as specified by the manufacturer. I am glad I did not have to try to get them apart on the transom...I would have likely torn the mounting screws out trying. One other thing, note the fuel hose connector size that comes with the filter - it may or may not be the same as your fuel line (for some reason my Suzuki has a 5/16 line coming out of the engine and the rest of world seems to be set up to use 3/8).

Thanks for the info, I ran into the same deal with the plastic tank & engine connector on my Suzuki being 5/16. I couldn’t find anything on the web on it so I took it off and while I was at Walmart I matched it up to a Scepter brand Yamaha #05815 one with a 3/8 barb and it fit right on.

[Russ]

Saves having to open the cowling to access the engine filter which is generally on the aft end of the engine down at the base of the cowl where is nearly impossible to reach. Btw: most engine filters don’t have a water drain so you’d have to not only remove the filter (awkwardly at best) but then reinstall a new one

True dat.

I have the same engine (DF70) and the fuel filter isn't accessible by just removing the upper cowling. You need to partially remove the lower cowling which is only doable if the boat is out of the water or you are a monkey.

Also, only buy a genuine Suzuki filter for the motor. Last year I replaced mine with an OEM filter that must have been sitting on some shelf for 20 years because when I went to launch the boat (put gas in it) it started to leak. The filter has this rubber tip thing at the bottom. I presume it's to drain water or some such thing. That rubber piece was leaking fuel from dry rot or just cheap material.

So there I was at the boat ramp spewing fuel out of the motor. Fortunately I had some spare hose bits that I could make a temporary plug and could launch my boat.
I then bought a new genuine filter and the next week attempted to replace it from above removing the upper cowling. No joy. After squeezing into the space I was able to transplant that rubber nipple from the new filter to the installed filter. I changed the whole thing out once I pulled the boat at the end of the season.

In my opinion, the filter in the motor is a secondary backup filter for insurance. There is no way to change it on the water. On LAND, it's easy peezy to change by removing the lower cowling 3 screws and 2 latch pins for full access.

Changing the oil is easier by removing the lower cowling also.

Suzi was nice to also include a standard garden hose fitting to connect a hose for running the motor on land for cooling without the need for those difficult "ear muffs".

The nearest Suzuki dealer is 300 miles away so I've learned to do all the PM myself.

[kmclemore]

The filter has this rubber tip thing at the bottom. I presume it's to drain water or some such thing.

Russ, that's to drain water, but also to drain the system at year's end... prevents old gas being stored in the motor. At the end of the season you drain that, drain the pipes, and remove any remaining the gas from the fuel tank(s). This way you start the new year with a fresh tank of gas, and fresh gas in the motor, which contributes to better reliability over time.

[LordElsinore]

Suzi was nice to also include a standard garden hose fitting to connect a hose for running the motor on land for cooling without the need for those difficult "ear muffs".

I always understood that hose connection port to be a "flushing port only", not to be used when the engine is running, and that earmuffs still had to be used in order to cool the engine when running it on land

I read it somewhere online so obviously it must be true

[Russ]

I always understood that hose connection port to be a "flushing port only", not to be used when the engine is running, and that earmuffs still had to be used in order to cool the engine when running it on land

I read it somewhere online so obviously it must be true

Hmm.. Interesting. I didn't read that and have been hooking up a hose to that port. When I do, the "pee" stream starts to flow and water comes out the prop. I've run it this way for several minutes (to run out gas) without issue. Been doing it since 2008 every year.

Maybe I'm doing it wrong, but so far so good. (I hope I didn't just jinx it)

My old boat had ear muffs. I never felt good about them. They seemed to fit poorly.

Now I have to use that interweb thingy to research this.

[Shane anthony]

I have read lots of posts here and elsewhere about adding pre filters, seems there are plenty of useful thoughts and opinions. So i guess my question is is this a terrible idea? I’d like to install this setup and change the filter annually. If clearance allows I’d want it in the transom pocket on the side forward the outboard. On the end of my fuel hose tank side I have the priming bulb and a quick disconnect. So it would be tank, bulb and filter down lower then tank and bulb then engine. It’s only a pre filter so 20 microns is fine I’d still be changing the stock filters on the outboard on the regular maintenance schedule. Just looking to add something simple to absorb a little water maybe but not cause issues when I’m out trying to relax. I did read someone’s comment you couldn’t use this filter on electron fuel injection? No mention of what outboard just the injection type. First I’ve heard of this but maybe common knowledge I’m definitely no expert. Thanks in advance for any feedback

I'm sure you read this thread, but here it is in case: viewtopic.php?t=29150&hilit=fuel&start=30

The was some fine print on the Sierra installation doc that said to install the filter BETWEEN the primer bulb and the motor, but no explanation as to why. At least OverEasy and I don't have it installed that way, with no problems yet.

It's important to source the appropriate teflon tape: fuel-rated tape is colored other than white, maybe orange, yellow or pink, and is specifically rated for gasoline. The white teflon tape used in commercial and residential installations is not the right product.

This is my installation. I like where it is, especially because it's under the dodger and out of the weather while on the water. It's mounted with two aluminum rivnuts and stainless bolts. When I haul out for the winter, I'll add another line from the second discharge terminal that I can use to siphon-drain the tanks, or to refuel the kicker motor from the main tanks.



AFTER I completed my installation and went through the misery of getting the right valves, I found this two-fuel-tanks-adaptor at the Marine Warehouse:
https://www.entrepotmarinemart.com/en/t ... 8-ses52699
It would have been much easier to use this, but on the other hand I'm not sure that it gives the "both" position option as my current setup does.

Hi thanks for the info, was going to do the same as you but wanted to know what rivnuts worked for you? Thanks

[Starscream]

Hi thanks for the info, was going to do the same as you but wanted to know what rivnuts worked for you? Thanks

Ouf, I wish I could tell you. I'm guessing M8, but I buy my rivnuts and stainless bolts in packages of assorted sizes, like this one. Actually the bolt holes were pretty big so maybe even M10...
Problem is they aren't marked and I just dry-fit the ones I want.

https://www.amazon.ca/328PCS-Stainless- ... =8-10&th=1

[LordElsinore]

I always understood that hose connection port to be a "flushing port only", not to be used when the engine is running, and that earmuffs still had to be used in order to cool the engine when running it on land

I read it somewhere online so obviously it must be true

Hmm.. Interesting. I didn't read that and have been hooking up a hose to that port. When I do, the "pee" stream starts to flow and water comes out the prop. I've run it this way for several minutes (to run out gas) without issue. Been doing it since 2008 every year.

Maybe I'm doing it wrong, but so far so good. (I hope I didn't just jinx it)

My old boat had ear muffs. I never felt good about them. They seemed to fit poorly.

Now I have to use that interweb thingy to research this.

I looked at the DF60A user manual itself and it is a bit confusing, but I'll share what I found. In the "motor flushing" section, it mentions two ways of doing so. The first is with the motor running using a 'commercially available flushing device' (earmuffs) with a garden hose attached to provide water to the engine. The second is using the 'built-in garden hose flush port' without the motor running. Elsewhere in the manual it states not to run the engine if water isn't coming out the telltale, and I believe it does come out when water is flowing into the flush port, but nothing specifically saying it's ok to run the engine when connected to that flush port.

Found lots of mentions in less authoritative online sources with people offering their (sometimes stong) opinions, but I do wish it were more clear in the manual For me, I use the flush port if the engine isn't running and earmuffs if I'm letting the engine run, but would love more information if you find any

[Russ]

Thanks for looking in the manual. I should have mine someplace, I should look.

I've been flushing with the hose port for years. I don't run it long. Usually just to warm it a bit to change the oil.