fuel filter

vyger59

Cadet
Joined
Jun 6, 2009
Messages
7
I winterized my Mercruiser 3.0 but forgot to change the fuel water seperator filter. I'm not really sure how it comes off . now I just started my engine for the summer and it started but crapped out and now won't stay running.I didn't run it very long.

1. How do I change the thing.

2. Can I change the filter and am I good to go or ..Did I screw up anything??.

This is my first I/O . I have only had outboards.

Thanx
 

cooter2506

Senior Chief Petty Officer
Joined
Apr 8, 2007
Messages
733
Re: fuel filter

3.0 didnt come with a fuel water seperator installed. UNless it was added later. But it looks like a oil filter and just unscrews like one too. Follow your fuel line from the tank and see if it has one if just goes to the carb then you dont have one. How long did it run? Mechanical or electric fuel pump?
 

vyger59

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Joined
Jun 6, 2009
Messages
7
Re: fuel filter

Thanx for the reply

It almost ran to temperature the first time but I increased the throttle and it started to die then stalled. then turned over like it was flooded so I pushed the throttle all the way and it started , then when I backed off it started to die again , then started missing and running like crap. I pulled the plugs but they didn't look too bad to me.
The hose from the tank goes to the starboard side of the engine to what I assume is the fuel pump....It has a threaded fitting to an aluminum line that goes back to the carb..., I thought that was the water separater, but i guess it is the fuel pump, would there be a filter in there
All I feel is a screw or bolt head on the bottom...hard to tell cause I can't see it.
I just bought this boat at the end of last season and it ran fine when the guy started it for me.Also ran it up to temp when I got it home and didn't see a problem.

When I winterized it I put fogging oil into the spark plug holes...could that have caused this problem???

BTW ...it is a 2005 mercruiser 3.0
 

Gary H NC

Fleet Admiral
Joined
Dec 1, 2005
Messages
8,972
Re: fuel filter

Really sounds like bad fuel...
Did you use Stabil in the tank over the winter?
May be time to drain the tank,put in fresh gas and test from there...
 

cooter2506

Senior Chief Petty Officer
Joined
Apr 8, 2007
Messages
733
Re: fuel filter

No filter in the mechanical pump. Probably one on the inlet side of the carb. Fogging oil could be causing it I guess. I always remove my plugs in the spring and wire brush them to clean them up and recheck gap.
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: fuel filter

You should install a fuel/water seperator in the line, before the fuel pump...this is a basic requirement, with E-10 gasoline. If you need any suggestions on where to put this filter, I can show you where mine is.

Here is a link to "how to troubleshoot your fuel system":

http://forums.iboats.com/showthread.php?t=283269
 

vyger59

Cadet
Joined
Jun 6, 2009
Messages
7
Re: fuel filter

It kinda seems like it's the gas to me also that's why I was leaning towards maybe water ...The tank was filled with 15gal fresh gas(20gal tank) in November and stabizol was added to the tank...New plugs were also installed
I will crank the engine over tomorrow with the plugs out and maybe expel any fogging oil in there and see what happens.

Sure I'd like to see where you seperator is installed Rocky Road

Thanx
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: fuel filter

It kinda seems like it's the gas to me also that's why I was leaning towards maybe water ...The tank was filled with 15gal fresh gas(20gal tank) in November and stabizol was added to the tank...New plugs were also installed
I will crank the engine over tomorrow with the plugs out and maybe expel any fogging oil in there and see what happens.

Sure I'd like to see where you seperator is installed Rocky Road

Thanx

Took me a while to find the pics...they are in this thread!

http://forums.iboats.com/showthread.php?t=308874
 

vyger59

Cadet
Joined
Jun 6, 2009
Messages
7
Re: fuel filter

Thanx for the link...

I know there are quite a few possibilities on what exactly is wrong but I also know the boat ran good before I put it up for the winter.
Now that I've had time to sleep on it , I have a theory on what is wrong. I put the boat in a vinyl Shelter Logic storage shed for the winter. A lot of condensation built up in there from time to time to the point where the engine was even wet.
Could it be that the gas has water in it from condensation even tho the tank was full and the boat was covered?
If there is water, I don't really want to try and run the engine. How can I tell if there is water in the gas??
This a 2005 Bayliner 175 and the tank is not that accessible.The tank is full at about 20 gal.
And if I am right , how do I proceed from here!!
I am going to pull the plugs for now and put some dry gas in the tank and wait for any ideas you guys have on this..

Thanx
William
 

Shadow66

Petty Officer 3rd Class
Joined
Feb 21, 2009
Messages
76
Re: fuel filter

Took me a while to find the pics...they are in this thread!

http://forums.iboats.com/showthread.php?t=308874

Hey Rocky, one guy on there suggested non worm gear clamps for your filter...why? Did you change them and did they make some sort of a difference?

I ask because I have the worm gear type on all of my fuel system...I will change them out if they make some difference.
 

vyger59

Cadet
Joined
Jun 6, 2009
Messages
7
Re: fuel filter

I just finished reading the post on fuel or water/separating filters and
I am going up to West Marine to see if they have a Racor water / separating filter setup for me to install .
If I am correct , I hope this fixes the problem.

Should I also try and drain the fuel pump???

Thanx
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: fuel filter

Hey Rocky, one guy on there suggested non worm gear clamps for your filter...why? Did you change them and did they make some sort of a difference?

I ask because I have the worm gear type on all of my fuel system...I will change them out if they make some difference.

The theory behind those, is that the worm gear style can 'cut' into the hose when tightened...the flat style doesn't. I looked at those...and just left mine alone.

But...the experts do say that you should double up on the clamps. The nipples supplied with the filter units, do not have enough length to do this. If the one clamp is OK with the manufacturer...then that is OK with me. I just made it a habit to feel for any gas leakage whenever I have the 'hood' up. I don't expect to have any problems with what I have....

Happy boating!
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: fuel filter

Thanx for the link...

I know there are quite a few possibilities on what exactly is wrong but I also know the boat ran good before I put it up for the winter.
Now that I've had time to sleep on it , I have a theory on what is wrong. I put the boat in a vinyl Shelter Logic storage shed for the winter. A lot of condensation built up in there from time to time to the point where the engine was even wet.
Could it be that the gas has water in it from condensation even tho the tank was full and the boat was covered?
If there is water, I don't really want to try and run the engine. How can I tell if there is water in the gas??
This a 2005 Bayliner 175 and the tank is not that accessible.The tank is full at about 20 gal.
And if I am right , how do I proceed from here!!
I am going to pull the plugs for now and put some dry gas in the tank and wait for any ideas you guys have on this..

Thanx
William

Definite 'YES' on the posibble condensation...especially if you have E-10 gas.

The other reality could be phase seperation of the E-10...this starts the minute that the gas leaves the refinery. Marine StaBil could have helped both of these scenerios...but only before, not after.

Sea Foam works wonders for all kinds of fuel issues....
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: fuel filter

I just finished reading the post on fuel or water/separating filters and
I am going up to West Marine to see if they have a Racor water / separating filter setup for me to install .
If I am correct , I hope this fixes the problem.

Should I also try and drain the fuel pump???

Thanx

Racor is definitely the 'Cadillac' of filters...but you will find the extra length a bit of a problem. You will also pay dearly for the Racor label...!

Make sure, if you go the bottom bowl on the filter route, that you get the metal bowl (not the clear plastic)...that is the only legal setup allowed on an inboard engine!

Take a minute, and read both of the two PDF pages at this link...you will be a filter guru when you are done:

http://continuouswave.com/whaler/reference/fuelFilter.pdf

You will also learn that one of the best filters that they tested, can be had for less than $10...!
 

vyger59

Cadet
Joined
Jun 6, 2009
Messages
7
Re: fuel filter

Just wanted to update this post since I still don't have this engine running.
A friend of mine who works on Marine engines stopped over to take a look and told me to pull the distributor cap and rotor. He said they didn't look good to him and that probably was the problem.Well I got a new cap and rotor and the engine started right up and ran a minute or two then died. I called him and he said to check the screen at the carb inlet which I did and it looked pretty clean. I also pumped some gas into a jar to sit and check for water which was my best guess.. It doesn't appear there is any in the gas .So I put every thing back together. I tried to start it again and it turned over but did not start. I took off the (air filter)? and saw that gas was dripping into the carburator. Is the float hanging up maybe and flooding out the engine??. And could this be the problem all along??Also looks to me as tho the carb has been removed before.

One day later........
Ok the rain has let up and and I got a chance to have another go at starting my boat.Did not start at all. I pulled off the throttle from the the carb and manually pushed to see if it was getting fuel and it was. I pulled the no.1 and no 4 plugs and they were dry?? I expected them to be soaked with gas....not so.. i checked all the wiring ...don't see a problem... at this point I have given up for now.
 
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