Question about paint chips in fuel system

[stouchton]

My boat is a 2004, so I have dealt with this - basically changed fuel regulator (3x) and fuel cell. But wouldn't this also effect the injectors?? I do not know much about my injectors, besides being over 20 years old. The engines are 4.3GXI-E. I do not know if these injectors have screens, or if paint chips could simply get to the nozzle/valve.

If paint chips can gather in the injectors, can they be cleaned?? Or should they just be replaced?

I am planning on pulling the injectors this winter and having them tested. I do not have any real issues, just down a little on power (3800rpm max instead of 4200/4400). When I had way too much fuel pressure I had no issues with power. Now that fuel pressure is corrected (55psi idle, 50psi 2000 rpm no load) got me thinking I may not be getting proper fuel delivery.

Pulling the injectors might be a difficult project - clearance is nil.

I appreciate any thoughts.

 

[Scott Danforth]

do a compression check.

yes injectors can be cleaned

if you can get the spark arrestor off, you can get the injectors off.

 

[stouchton]

do a compression check.

yes injectors can be cleaned

if you can get the spark arrestor off, you can get the injectors off.

Thank you

I can get the arrestor off, so should be good to go.

Good idea on compression check. Changed the plugs yesterday but forgot my compression gauge, but simple enough now that I finally found a decent spark plug socket that fits under my GLM manifolds.

 

[cyclops222]

EFI engines can ruin engines with lightly blocked injectors. They start to run some cylinders smoothly LEAN.

 

[ESGWheel]

Please read this thread (link) explains a lot....

 

[BRICH1260]

Prop pitch can play into engine not getting to full RPM`s. Might consider looking there before tearing into engine.

 

[Scott Danforth]

but simple enough now that I finally found a decent spark plug socket that fits under my GLM manifolds.

standard socket with OD turned down.

 

[stouchton]

standard socket with OD turned down.

I have a perfectly good Atlas in the basement and never even thought of that. Got hyper-focused on finding a socket that would work!

 

[Lou C]

Did the manufacturer really stick the engines under an un-movable hatch?
If so, this is why some people will never have another inboard or I/O. But, if you can get to it, go for it!

 

[stouchton]

Please read this thread (link) explains a lot....

Great link. Left me with a question that might be a misunderstanding. How do the paint chips get past the screen on the high pressure pump? Is it simply too coarse to stop them?

 

[stouchton]

Prop pitch can play into engine not getting to full RPM`s. Might consider looking there before tearing into engine.

Props have been the same for 20+ years, so I don't think that is the culprit. They are pristine and not damaged.

 

[stouchton]

do a compression check.

yes injectors can be cleaned

if you can get the spark arrestor off, you can get the injectors off.

I did perform the compression check - 160 to 165 PSI on all cylinders.

I am planning on removing injectors this off season.

 

[stouchton]

Did the manufacturer really stick the engines under an un-movable hatch?
If so, this is why some people will never have another inboard or I/O. But, if you can get to it, go for it!

Yes they did. I called Monterey to inquire about access, and they suggested to cut the deck. Fortunately I am only 5' 8" and 160lbs so I can squish into some tight spaces. At age 61 the body does not like it.....

 

[stouchton]

EFI engines can ruin engines with lightly blocked injectors. They start to run some cylinders smoothly LEAN.

Good point - I did limit running once I got fuel pressure under control.

 

[airshot]

Once you get things cleaned up and running, consider adding more fuel filters or figure out where the chips are coming from. I always add and extra filter of two when I get another boat. My moto is you can't have to.many..

 

[airshot]

Did the manufacturer really stick the engines under an un-movable hatch?
If so, this is why some people will never have another inboard or I/O. But, if you can get to it, go for it!

When ever I looked at boats with I/O's, first thing I consider is access for service. I do my own, so easy access is primary. Walked away from some really nice boats because of poor acess...

 

[ESGWheel]

Great link. Left me with a question that might be a misunderstanding. How do the paint chips get past the screen on the high pressure pump? Is it simply too coarse to stop them?

I can say that the screen on my regulator was contaminated with fine black specs, so it does get past. And when I had my injectors cleaned, the report was “very dirty”.