50hp Perkins won't rev past 1900rpm

[Hoohaa]

Just a quick correction. My engine is a 104-22 not a 104-19.

[SkiprJohn]

"Where did you spray? Over the injectors?"

Into the intake manifold after you remove the air cleaner.

Since you've cranked it quite a few times and have heated your starter a bit don't crank anymore until you've got your batteries topped off again. You could burn your starter motor if the batteries are not giving you enough juice. Your engine needs to spin at a significantly high rpm to start. That could be why it hasn't started your last try. At your injectors there cannot be bubbles in the fuel when you bleed the engine. Has to be clear spray

I suppose you know not to keep your engine water intake open while spinning and not starting? Did we cover this yet?

[Hoohaa]

Originally Posted by SkiprJohn

"Where did you spray? Over the injectors?"

Into the intake manifold after you remove the air cleaner.

Since you've cranked it quite a few times and have heated your starter a bit don't crank anymore until you've got your batteries topped off again. You could burn your starter motor if the batteries are not giving you enough juice. Your engine needs to spin at a significantly high rpm to start. That could be why it hasn't started your last try. At your injectors there cannot be bubbles in the fuel when you bleed the engine. Has to be clear spray

I suppose you know not to keep your engine water intake open while spinning and not starting? Did we cover this yet?

Didnt kmow about the water intake until Bob meantioned it yesterday.
And will take it a bit esier on the sterter from now on. Thanks.

[Hoohaa]

I am starting to lean towards.
-Replacing the number4 injector.
-Going over the fuel system to check for air leaks and have another go at bleeding and starting it.
-Find a schematic showing the internal workings of the governor in order to fix the original reving problem.

I don't think there is anything wrong with the injection pump, I think it has nothing to do with the original Rev issue.
I think the fact that No4 injector did not spurt out fuel like the others, it is fualty.
Feel free to change my mind and come up with alternatives.
In the picture below, The PERKINS badge is attached to the part wich I believe is causing the reving problem. Can some one tell me what its called so I can try and find a schematic on it?
Thanks.

[forsailbyowner]

Before replacing injector I would remove them all and take them to a shop and have them serviced. The last time I did mine it cost $100 to clean, pop test and inspect all 4 of them. Somewhere in the manual it says to do this annually. I think i got a break when i paid what I paid, it was a close friend who was a diesel mechanic that had it done for me at his favored shop.

[Hoohaa]

I will probably buy a kit for each one.
Was just talking to a mate and he made a good point. Injector 4 dribbles fuel instead of spraying it. He thinks that the fuel may not be entering the injector under enough pressure. In other words there could be a blockage in the pipe. Sort of makes sense. So I might give It a clean.
Anyone got a name for the part above yet.?

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[Oceanride007]

Heres what a Banjo looks like. Anneal the copper washes, your gas ring should be up to it.
Hoohay said “I think the fact that No4 injector did not spurt out fuel like the others, it is fualty.”


So did you test the injectors by pulling them out and reassembly on to HP pipe and cranking! Err One at a time or all of em?

You are even rougher than I. and a unwise, injectors also stop hot gases getting out, hot gases can erode your engine block.

If you did that, well have a go at fixing it.
Injectors are another precise piece of gear, If fuel didn’t come out the FI Nozzle, the nozzle holes are blocked, or its associated Fuel pump has a problem. You could try getting Nozzle cleaning wires from CIG the type used for cleaning gas cutting gear. I’m a little uncomfortable about cleaning from outside, but you already proved you are rough! Better than pulling injector apart without the right gear.

Anyway one faulty injector is not causing your problem, could be you are being distracted.

FYI the priming pump should have a lever for priming purposes, but a lot of old salts can’t be bothered cose it takes long time. I had a V16 once that I’m sure only fired on 1 or 2 cylinders after Bosch fuel pump O/haul, but the increased revs had that engine purring 10 seconds later. Really it shouldn’t take much to prime your system.

That thing under the Perkins decal, that’s the fuel pump block, Possibly where the governor is. (Note: If you have a 4 cylinder, then you have 4 fuel pumps in that block). It would be nice to know, which side of the Governor we have (my alleged) sticking problem.


A little worried we are creating more problems.
If you pulled injector out, the injector pocket and injector have to be clean and gas tight. It could be metal to metal or a special washer that may need to be replaced or relapped. Careful we could be talking grinding paste and mandrels if you get it wrong.

That S/D solenoid may need to be investigated for proper function, does it look easy to disconnect.


Disclaimer:My logic comes from a 1/2 life time of repair in remote places, these days it may be better to spend the money. But I also think its important to self learn, A technician thou clever can solve the problem but only by changing out everything until the problem is solved. I want the OP to be in a position where the diagnoses is accurate and the list of changed out parts is very short.

[Hoohaa]

Rough! Not shore what you are referring to.
I haven't removed any of the injectors yet. We have only observed them while each of them were bled. No4 dribbled instead of spraying.
As I understand. One injector not working will prevent the engine from starting.
So. Is it unwise to remove the injector because it's difficult to gain a seal when you replace it?
My plan was to remove and clean the pipe that runs to that injector.


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[Hoohaa]

Yes. An accurate diagnosis would be great.

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[brutb]

Hoohaa, I will tell you a noobie problem I had with a Perkins 4-108. When I first bought my CSY 37 and after replacing frozen starter I bled the fuel injector lines and could still not get the little sucker to fire or run. It turned out that the manual fuel shut off pull cable was run from the front of the engine and not the rear. Most boats have the fuel cut off know to be pulled to kill engine. After having injector pump and 4 injectors serviced and reinstalling the gear and bleeding the system the engine still would not run. Back to the injector overhaul place and ask which way does the fuel cutoff lever move to cut off fuel. On my engine the arm on the side of the pump moves aft to cut off fuel, forward to allow fuel to pump. After pulling on fuel cut off now the darn engine fired on the first 2 ticks. Sometimes it is the simple things that cause the problems. Yep I am the guy that called you "not a gear head" so even gear heads get things wrong.....LOL

[Oceanride007]

Hoohaa you did say, “Injector 4 dribbles fuel instead of spraying it” This implies you took it out. Injectors need be cleaned, tested for crack pressure, spray pattern examined, antisieized, torqued, anything else would be considered, bit hasty, bit rough.

This technology is dead simple if you follow a cause effect relationship. Having random thoughts like changing #4 injector would not be helpful and would not be matched to the others. The Fuel injector is after the HP pipe, spray pattern is determined at the nozzle in the combustion space, what were you thinking. Your perception of unbalanced fuel distribution has no place here.

With respect, do nothing more than, check the Shutdown devise (S/D) get that engine primed and running. And before you do anything else bone up on Fuel Regulation.

[Hoohaa]

I was observing the fuel when we were bleeding it. ie. Cracked the nut on top of the injector and cranked to get the air out. The first free spurted out. No4 dribled out.
This is before it has gone through the injector. So that's why I am thinking it could be a blockage in the pipe leading to the injector?

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[Hoohaa]

Found this in my original thread which shows a detail of where my rev problem is.

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[SkiprJohn]

Originally Posted by Hoohaa

I was observing the fuel when we were bleeding it. ie. Cracked the nut on top of the injector and cranked to get the air out. The first free spurted out. No4 dribled out.
This is before it has gone through the injector. So that's why I am thinking it could be a blockage in the pipe leading to the injector?

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Yes, it could be. It could also be that you didn't have that nut open as much as the others when you did bleed it. It could also be that the injection pump is contaminated and not sending enough fuel through the pipe. It's easiest to take the pipe off, run some acetone through it, blow it out with compressed air, replace it and try again.

[Oceanride007]

Sydney to a brick, your fuel pipe is clear, because with any kind of debris would cause your fuel injection equipment to crap out long ago.
But if you have the urge, do it, your not likely to cause consequential damage, unless your careless and twist the pipe. These are not easy to replace.