Calling diesel engineers .......... hosing ?

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peterandjeanette

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For several months I have been bemoaning the fact that every time I go out in the boat I come back with the stern coated in a black oily crud that goes beyond just a smoky exhaust.

I accepted that this usually indicates either lack of air or too much fuel. Thorough investigation has shown up that some of the injectors are hosing. ( I understand this to mean that they are ejaculating diesel into the cylinders rather than spraying.)

OK, now for the questions. (Engines are VPs - TAMD 63P 4 years old with 340 hrs on the clock, regularly serviced )

1. What causes hosing?

2. Why 5 out of 6 cylinders on one engine - and not the full 6?

3. Why is the other engine totally OK when the same fuel (always treated with addatives, usually S**tron) is used in both engines?

4. Has it bu&&ered the cylinders/pistons (been happening for last 120 hrs)?


As I've never heard of this before I'd be interested to hear of anyone else with this problem.
 
1. What causes hosing?

2. Why 5 out of 6 cylinders on one engine - and not the full 6?


........................................................................................

Injectors can fail for a number of reasons depending on fuel quality filtration standards and even quality of previous maintenance.

You seem to have discovered that 5 out of 6 injectors are hosing.... How did you identify this????? Are you 100% sure all injectors are OK on the other engine.

Runing an engine with 5 out of 6 nozzles hosing would result in lousy running ,lots of smoke and even vibration to match a one bladed prop. The resulting side effects would be fuel dilutution of the sump oil,excessive cylinder and piston wear as well as clogging up of turbos.

Are you really sure that 5 nozzles are hosing??? WHat test. If five nozzles are fully hosing then the engines must sound like crap!!

I once found a very disillusioned mobo owner on a near by pontoon and asked what the problem was. The marina enginners had just quoted two arms and two legs and more to replace outdrives and props. Being a nosy b**ger I asked him to lift the legs and let me have a look.. I suggested his vibration might be caused by something else and if he had time I d go out and check both engines.

We did a quicke run up and down on the Forth and when we got back told him he had duff injectors on both engines in fact three cylinders on each engine were not delivering power.

I can t believe these engines will run on 1 cylinder /forums/images/graemlins/laugh.gif

Take all your injectors to a good diesel shop and also make sure your filters are clean and doing their job .
 
Engine still running reasonably well, but down a little on power.

The diesel was still getting through but not in the fine spray to ensure full combustion. Thus an unburnt quantity was passing through and exiting through the exhaust in black smoke and depositing black oily grime on the stern. Fuel filters not a problem, but the foam air filter seems very oily!

So far the results on the other engine are not confirmed. However this exhaust is the usual VP blue so I don't expect any trouble - always the optimist.
 
I find it hard to believe that your injectors are in that condition after 340 hours, the phantoms are renown for black on the back of the boat, every one ive seen is like this.

Mate has just had 12 new injectors, they had done 1200 hours in a 1988 boat he has had from new and to be honest its made no improvment and hes over a thousand pounds poorer, now hes south coast based, i do a little work down there and every time you take injectors in to be tested there is usually nothing wrong with them at the local bosch specialist.

Sounds more to me like the usual south coast money making racket, you find that over the years the boat gets heavier and the load on th engines is greater so the engines are loaded more and will black smoke, 63p do black smoke anyway so theres little to worry about.

By all means get them tested but have it done by a non marine company so to get a totally unbiased opinion.

You can also get a report with the opening pressures and spray pattern, leak off figures etc, though by the sound of your post you have already had them removed by a dealer, they will sell you volvo penta exchnge injectors, i have come across this before they are sometimes recons made in Brazil, better to have them done by a bosch agent as you will get genuine new nozzles, MB Diesels in Southampton are good.

Of course it could be a turbo boost problem as the 63p turbo has a wastegate and these do stick open and sometimes the valve falls to pieces and dissapears down the exhaust!.
 
A forinstance, my Mate Yanmar 420 hp, no revs over 1600, black smoke, says I "air" says all the experts turbo, injectors, waste gate, pump, says I "air", all connections are good no leakage, STILL AIR, check inlet tract from start to finish, ok, no play on turbo shaft, all joints and gaskets good, but filthy air intake filter foam, and exhaust gasket slight blow, "NO NOT THAT", AIR. Finally the intercooler was removed and lo and behold it resembled a brick yard in there, removed the core and thoroughly cleaned, Hey Presto full power and no black smoke.
 
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