Replacing a fuel filter (454)

[pschauss]

As I tried to return to Oakdale from Sailors Haven this afternoon my starboard engine started to cut out at anything above idle speed. I managed to get about 7-8 knots with port engine running at 1200-1500 rpm and the helm hard over to port. Luckily the wind was mostly out of the south and there was very little chop on the bay so I made it back in about 30 minutes.

Since the starboard engine idled ok, I am suspecting a fuel system problem, so I will start by replacing the filter. I plan to turn off the fuel valve, run the blowers, and use a metal bucket to catch any gasoline which spills. Are there any other precautions that I should take?

Thanks,

[Carl]

Little oil on threads and seal of new filter....assuming a spin on.
Let boat air out before cranking them up and checking for leaks.



In any case I also like to bring a clear glass bottle to dump contents of filter in.
-One you can transport the fuel in it if capped
and to me, more important I like to see what the filter took out.

Carefully away from boat pour funnel contents into bottle and let sit a few minutes to settle.
Now take a look...a few particles is fine, I pour clean fuel back in tank the rest I dispose of.

Alot of crap and some water droplets on bottom...well..depends on last time you changed filters. But consider changing more often, keep spares on boat and keep checking till it clears up. If it does not and you know your getting clean fuel...look to bad tank plate seals, fittings, hoses, tank issues.

[Stephan]

My Crusader 454s have an additional filter at the base of the carburetor. It is a small screen where the fuel line enters the carburetor assembly. I have found that my filters keep the carburetor screens clean but it might be worth checking.
I also have a third filter that is installed before the Garmin fuel flow sensor. It's required by Garmin installation instructions. If you have GFS10 fuel sensors check for this filter as well.
I have used a clear freezer strength zip-loc bag when removing the filter. I think it does a better job of catching any spill and lets me see if there is significant "stuff" in the residual fuel. I don't recommend expecting the zip-loc to hold the fuel for long...
Good luck,
Stephan

[Donmystic1]

The filter in the carb is the most suspect.
If it is a screen you can blow it out with your breath till clear.
If a paper type it will need to be replaced.
Both have a separate spring behind the filters don’t lose it.
You will need a 1 inch open end wrench and a 5/8 “C” or pipe wrench to remove the gas line.
Just put a paper towel under the nuts to soak up any small amount of gas that will drip out.
If you use a regular 5/8 open end wrench you will round off the corners and then have to replace the fuel line

[Yannis]

Carl,

This is why I will never be a diesel common rail engine purchaser. I’ll burn more, but I will not have any of these problems, I don’t want problems!

[Tony Meola]

Peter

Not sure how your filters are set up. On our old 454's we only had the spin on. None in the carb or fuel line.

You really do not need to worry about gas fumes. Not much fuel will drip. As said use rags under the line at the Carb if you need to check it for a filter. Leave the engine cover open for ten or so minutes you should be good. Then run the blower for ten minutes or so before starting.

I would change both the spin on and the one in the carb if there is one. The spin on could have water in it. I would also do the other engine while you are at it.

Make it a habit to change the spin on's every spring. Usually first thing I do when we uncover the boat. Normally don't start the engines until the boat is washed waxed and bottom painted. Since that is several days after changing filters no issues with fumes.

If that does not work, then it is probably the fuel pump.

[Carl]

[quote="Tony Meola"
You really do not need to worry about gas fumes. Not much fuel will drip. As said use rags under the line at the Carb if you need to check it for a filter. Leave the engine cover open for ten or so minutes you should be good. Then run the blower for ten minutes or so before starting.

[/quote]

My upbringing has taught me, I can leave hatches open and let blower run for hours- -Or- - don't open hatches and don't run the blowers...BUT BEFORE I crank those motors over, I stick my head in the the bilge, in the engine compartment and do a sniff test.

SNIFF for fumes, if I Smell 'em, I don't start 'em.

Same as before starting motors each day, after extended times, after fueling up.
Nose clogged, grab a friend.

[Joseph Fikentscher]

Before fueling, close every window, hatch, and door. After fueling open every window, hatch, door, engine box and run blowers. After starting close engine boxeses and anything else you want closed.

[Donmystic1]

When you reinstall the spin on fuel filters fill each 1/2 full with “sea foam” fuel treatment.
This will give your carbs a full shot of cleaner which may remove any water molecules in the passages.

[pschauss]

Thanks for all of the suggestions. The owner of the marina where I dock offered to look at my stalling problem. He he pulled the filter and the screen at the carburetor. He said that the filter looked good. There was some debris in the screen but he said that it did not look like enough to be causing the engine to be cutting out above idle speed. He also ran the engine at the dock (small craft warnings from the remnants of Michael prevented testing in the bay today), but did not see any problem.

He suspects that the coil is bad and lent me a new coil with the suggestion that I run the boat in the bay and swap the coil if the problem recurs. If the weather permits I will try tomorrow and post results.

[Mack]

Sounds all too familiar. Swap the coil with the "good" motor. If that is not it, replace the fuel pump. We confirmed the fuel pump as the issue by disconnecting the fuel line and cranking the motor with a rag under the open fuel line. The flow was weak so the pump got replaced. No more issues. Good luck and keep us posted.

[Tony Meola]

Peter

If you start off shore trips, try and add some spare parts if you can. Spark plugs, coil, spare fuel pump and sea water impellar. I always found it tough to change the fuel pump on those 454 chevy blocks. I always had an issue getting the pump arm lined up right. But you should learn, so if it is the pump, change it yourself with someone who knows how standing over your shoulder.

My father could do it with his eyes closed but that was his business from the time he was 15 years old. After he passed and I had to do one, I wished I payed more attention.

Of course the first one you do will follow Murphy's law and be the one on the starboard engine so you have to hang upside down to do it.

[pschauss]

Turns out it was the aftermarket electronic ignition kit. I replaced it and went for a test run. No problems so far.

Interestingly my starboard engine, the one which was giving me problems, has a Mallory distributor with a pointless conversion kit while my port engine has a Perstolite (IDU 7801BS) which appears to be an electronic distributor.

Thanks for all of the suggestions.

[Pete Fallon]

Peter Schauss,
I would check to see if you have a ballast resistor somewhere in your electrical system. Years ago I had a pair of 440 Chryslers that would run fine until the ballast resistor heated up then it shut the engine down almost like it was stalling from lack of fuel, after it cooled down the motor would run fine until heated up again, drove me crazy fore a couple of weeks before I had a top marine mechanic go over the entire electric and fuel system. A simple electrical part was the cause of a lot of swearing and frustration that summer. I changed to 454 7.4L Mercruiser's with new electronics and fuel injection never had a problem gain.
Pete Fallon

[Joseph Fikentscher]

Same problem, but mine was a cracked 50amp fuse with the reset button. Engine would start, shut off when warm, and start again after cooling down. Bugger of a time finding the culprit.

[Seamcdog]

Sure am glad I read through all the posts..... Alot of good information.