Don - Injector cleaning question

[DG]

So as to not hijack another thread I'll start a new one. Don, you replied to another post with this statement:

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by EuropeanAM &raquo;</td></tr><tr><td class="quote">
BTW... it's ALWAYS wise to have the injectors cleaned/flow tested/ and recalibrated as needed.
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My question is, how do you know this is needed? What are the indicators that you have an injector problem?

I have a '95 Mariner 200 EFI and I really don't want to be blowing the engine because of an injector problem so I would like to know what the early warning signs are.

Thanks for your time and knowledge.

[EuropeanAM]

In order to PROPERLY determine if an injector is functioning PROPERLY... Professional FLOW TESTING is required.

There are "field" methods through which you can make a "rough" determination... such as reading spark plugs, cylinder misfire tests, etc. However... since there are at least a DOZEN other possible causes for improperly firing spark plugs or imbalanced misfire tests... extensive further testing may be required before you can accurately conclude that an "injector is at fault".

With today's fuels, I strongly recommend having your injectors cleaned and flow tested at least once every 3-4 years, or whenever performance problems are present that cannot be CONCLUSIVELY attributed to another (solvable) cause.

[THE WITCHDOCTOR]

Don has all my setup right now, and I am glad I did! I have basically the same engine as you, and ALL 6 of mine were off. Don has really did a job on my stuff getting it back like it needs to be. I would strongly advise to send them in and let him work them.

[DG]

Were you having any problems that caused you to send them in? My engine starts immediately, idles smoothly, and doesn't seem to have any performance issues at present. I don't have oil injection, I premix and run Seafoam in every tank (1oz per gallon).

[THE WITCHDOCTOR]

Mine had gotten a little tough to start, but other than that it ran like a raped ape. I had some line issues back in the summer, and when I drained my VST I found alot of rubber from the old line.... so that lead me to think that it was probably in the screens for the injectors.... they were bad out of calibration..... it is cheap insurance to do it... plus, when I tore mine down, I found a ton of other stuff that would have never been caught.... got a little expensive, but I know when it comes back it is RIGHT.

[EuropeanAM]

And I'll add that in Craig's case (Witchdoctor), there was a substantial amount of metallic debris built up in the filter screens, pressure regulator, etc. (due to a previous fuel pump failure). VERY timely catch.