Merry Christmas all,
I have a troubleshooting question. Started up Matchmaker the other day and after a few minutes we heard a hissing sound start up. Intermittent, increasing in speed with RPMs, sounds like either compression or suction leak. Hard to determine where it originates. On inspection I found a minor diesel leak in one of the banjo fittings off the filter but no other obvious issue. Tightened the fitting, still leaking a bit so I'm going to replace the banjo washers. Suggestions so far have been to have a look at the seating washers for the injectors. Any advise?
Ron
Matchmaker P-365 Ketch
Lying Saint Marks Florida
Check the exhaust gaskets closely. If you find one with soot around it, it's leaking. The bottom can be a little difficult. You can check it with a mirror, or by feel. Wipe your finger under the exhaust port and see what is on your finger. If you find soot, it's leaking. Exhaust leak seems most likely- check for this closely.
If you don't find anything there, pull the screen (cap) off the intake and start it up. See if the noise gets louder. That could indicate a valve or valve train problem.
The sealing washers for the injectors are pretty easy to check. Start it up and spray a little soap and water around the base of the injector with a squirt bottle. A small amount of seepage is fairly common. If you have a significant leak it will be obvious.
Does it run smooth? The noise is not accompanied by a missfire?
She runs as smoothly as ever. No roughness associated with the new noise. I will be heading back down on Monday and will check the exhaust. I did pull the air filter and also opened the oil cap and did not notice any increase in noise. I'll also try the soap and water test you suggest. The injector bases appear completely dry however. The only seepage I can see is around the banjo fittings coming off the secondary fuel filter housing just above the lift pump. Thanks for the suggestions.
Ron
I would bet on an exhaust leak.
Thanks, I'll let you know.
Ron
Well, I can't find any issue with the exhaust. I went through fixing the seepage around the banjo fitting on the secondary filter. Still hissing, still intermittent and in sync with the crankshaft. In fact, on shutdown I can clearly hear it hiss a couple of times as the crank turns over that last time. I went through the process of bleeding the whole system and, to my surprise, when I got to the injector inlet lines I couldn't get any flow using the lift pump. No flow from any of the four! This despite a good flow from the injector body bleed point. Still - the engine cranks and runs!! How can that be with no flow from the injector pump?? I even tried bumping the started a couple of times with no luck. Could the hissing be an overworked lift pump compensating for a failing injector pump? Seems unlikely. I'm stumped.
Any thoughts?
Ron
S/V Matchmaker Pearson 365 Ketch Hull #311
Lying quite still at Saint Marks Yacht Club - Saint Marks Florida.
I doubt the lift pump is the source of the noise. What happens when you put the transmission in gear and load the engine?
You won't get flow from the injector lines with the lift pump. You have to spin the engine with the starter to bleed the injector lines.
Well, here's the answer. Embarrassing but may save someone out there the two plus days I spent tracking down a mystery noise. After bleeding the entire system, and right you are - I had to spin the starter to bleed the inlet lines to the injectors, retorqing the head and all the injectors, installing new injector seating washers, and more time spent trying to track the the sound source than I care to remember I finally found a hose clamp where the end was vibrating up against the underside of the heat exchanger. The rapid vibration sounded for all the world like an air leak. Anyway, and here's the useful part - A diesel mechanic told me to take a piece of flexible rubber hose, put one end in my ear and explore around the the engine with the other end to see if I could localize the noise. I pulled a flexible piece of silicon hose off a water filter and hocus pocus - Worked like a charm and thus located the offending clamp end. Lesson learned and although it cost me sailing on a beautiful day today, the fix was cheap. Now - anyone want to buy some extra injector seating washers?
Ron
Ron,
Time well spent I would say. I would call it maintenance, and it is good that you didn't have to spend $80 plus and hour for someone else that knows less than you to find it. Many people would not have even caught that noise. How many do you see along the road with a trail of oil leading to the shoulder? I am sure there was an ignored noise over the past months in that case as well.
That noisy clamp tail could have rubbed through your heat exchanger, and retorqing the head bolts and replacing banjo washers is a good thing. My Tilly is off to you for having the ambition and desire to get after it. Most people use the excuse they do not have the ability, but the truth is that it is the ambition and the desire to learn and do that are the most important two things.
Good Sailing... Dale
Nothing to be embarrassed about. An "acoustical phenomenon" can drive you nuts if you let it. Sometimes a vibration will masquerade as something else. My favorite is the strange noise that is coming from somewhere else. Maybe it's a harmonic, maybe it's an echo, who knows. When you finally track it down, the source was nowhere near where the noise seemed to be coming from. We all get used to what we have and the noises it makes. It doesn't matter whether it's a boat or a lawnmower. When a new noise appears, you pick it up and want to know where it is coming from. I don't like new noises. They are usually the precurser of an impending problem. Failing to pay attention to them will put you on the wrong end of a towline.
here is a good little trick
if you can not locate a knock,rumble,ect hold a long screwdriver handle to your ear and place on differant parts of the engine,alt,water-pump,rocker cover ect,
just don't place it on any moving parts...ouch
oceanpilgrim
I have to agree with your mechanic. I liberated a toy stethascope from my daughters toy medical kit many years ago. She Is now 27 and always comments when she see's me using them. They have been a valued part of my tool kit ever since.
The cheap plastic tubing has been replaced and with auto windshield washer tubing and has saved hours of trial and error hunting. A highly recomended additionfor tracing all sorts of noises. Anothe tip I picked up years ago is if you suspect you have a leak, diesel or water wait until dark and investigate using a flashlight. Fine mist shows up better at night in the beam of a light.