Isuzu 35 - time to get injectors cleaned?

[Awayonmyboat]

My boat is 16 years old and fitted with an Isuzu 35 engine with a recorded 1500 hours on the instrument panel. It has had regular oil and filter changes but I do not if anything else has been done.

 

I have owned it for a year / 200 hours. During this time the engine has run very well with the only issue being that when using a quick bursts of throttle during manoeuvring (such as turning at winding holes) it briefly produces copious quantities of white smoke. 

 

Do these symptoms suggest  getting the injectors cleaned would be a worthwhile investment? Or are there any other suggestions.

 

If the consensus is yes, are there any special tricks and tips I should be aware of when removing Isuzu injectors?

 

Many thanks in advance.

 

 

[cheesegas]

I don't know how similar the newer Isuzus are to the older ones, but I've got a 30 year old 3KC1 in mine which smoked black under load because of two worn injectors. I bought a set of new old stock ones on ebay, have a look as they come up occasionally. Mine came out without a struggle as they've very short.

 

Anyway, I'm no diesel expert but white smoke under load is either totally unburned fuel or steam from a head gasket failure. As it seems to run fine, I'd bet its unburned fuel. Does the smoke smell bad?

 

Check your air filter to see if it's really plugged, and if not then either send off the injectors to be tested and refurbed. It could also be a timing issue with the fuel pump, but as this is adjusted with shims on the two Isuzus I've seen, it's unlikely. 

[Mike Adams]

I would say it is fine. My Isuzu does that as well as I suspect most engines do. If is smokes on a steady high load, such as on a river, then something is worn or needs adjustment. Remember when you wack the throttle open quickly it overfuels in order to accelerate hence the smoke. 1500hours for an Isuzu is nothing.

[Tracy D'arth]

Needs a good thrashing. If its only done 1500 hours in 16 years it has been underused.

[Bee]

That's not many hours for mechanical things to need attention. although lack of use can produce its own problems. Does the engine get up to a reasonable temp? probably at least 60C ? Use water?  Is the white smoke actually steam?  Steam disperses v. quickly wheras smoke lingers.

[Awayonmyboat]

Thanks everyone for the replies. As I said the engine runs fine. I know white smoke is normal when the throttle is wacked open - but I feel (though with little relevant experience) mine is excessive. It is definitely white smoke not steam and temperature is a consistent 80c. There is no sign of smoke in normal running even when I was pushing against some current on the River Severn last year (although as I had no working temperature gauge at that time I was deliberately not working the engine hard)

 

 

I think as a first step I will follow Tracy D'arth suggestion and go and give it a good thrashing and see what the result is. Also I might try Blizzards suggestion (which I have just found on another thread) of running some neat Redex through the fuel filter. If neither of those make a difference then I'll get the injectors cleaned at the end of the year.

[Tony Brooks]

10 hours ago, Awayonmyboat said:

Thanks everyone for the replies. As I said the engine runs fine. I know white smoke is normal when the throttle is wacked open - but I feel (though with little relevant experience) mine is excessive. It is definitely white smoke not steam and temperature is a consistent 80c. There is no sign of smoke in normal running even when I was pushing against some current on the River Severn last year (although as I had no working temperature gauge at that time I was deliberately not working the engine hard)

 

 

I think as a first step I will follow Tracy D'arth suggestion and go and give it a good thrashing and see what the result is. Also I might try Blizzards suggestion (which I have just found on another thread) of running some neat Redex through the fuel filter. If neither of those make a difference then I'll get the injectors cleaned at the end of the year.

 

If you try the red bit for goodness sake only drip it in. That is an ideal way of creating a hydraulic lock and bending con rods. It would be better to put injector cleaner into the fuel filter and the rest in the tank and run it. The redex trick works against carbon around the rings and valves, not gum in the injector nozzle.

[BEngo]

What Tracy said.

  Give it an Italian tune up. Open the throttle to black smoke then back off to either no smoke or the speed limit, whichever is slower.   The Severn or the Trent are best because you can run at full useable power for long spells

  The Thames reaches are a bit short,unless you go up and down one of  the longer ones.

 

N

[Awayonmyboat]

A bit of late feedback. A series of Italian tune ups on the river Severn over the last year, seem to have done the trick. Smoke levels now much reduced. My wallet thanks you all.