The Ten Commandments of Diesel Maintenance

[GordMay]

"The Ten Commandments of Diesel Maintenance"

1. Thou shalt keep thine engine clean and in adjustment that thy life in its company shall be long and that the owner shall increase thy job longevity.

2. Know thine engine and all its parts and functions, else thou shalt be up some tributary without means of locomotion.

3. Be not wise in thine own conceit. Remember the factory instructions and keep them holy, lest false repairs be thine undoing.

4. Be not loose in thy jaw hinges for no man knoweth all about diesels. The truly wise absorbeth much knowledge and exceedith little, and he who so doeth shall gain repute among his fellows and favors among his superiors.

5. For all things in this life that thou desireth, thou shalt also pay plenty, and for the wisdom of experience, no less. Advice from the multitudes costeth nothing and usually worth as much.

6. In the books though mayest read what to do and when, but only the voice of experience may tell thee why and how, else reading of what and when shall but plague thee with smoke.

7. God maketh the earth rotate endlessly without bearing or oil, but not thy diesel.

8. Curse not thine engine when it turneth not. Curse rather thine own neglect.

9. Steam engines and gas engines may long turn over though sloppy: a diesel not so. With gauges and mikes be though ever busy.

10. The eternal eye watcheth universal operations, but thou shalt not rely upon it as to thy diesel. Thine own vigilance is the price thou payest for thy job.


Gord May

[Starbuck]

Amen.

[Talbot]

well yes if you say so. IMHO the most important point about diesel engines is the need to replace oil and fuel filters and replace the oil religiously when called for by the instructions. Other items can sustain a bit of benign neglect, but the neglect of the oil will soon screw up the engine.

[GordMay]

Some excellent Diesel Fuel Information resources:

”Long Term Storage of Diesel Fuel”:(from BP Australia)
http://www.bp.com.au/fuelnews/ADF1402.pdf
6-12 months at temps of 30* C or higher
or
12 months or longer at 20 degrees C or LOWER
An excellent article !!!

“Diesel Fuel - Fungal Contamination”:
http://www.bp.com.au/fuelnews/ADF1502.pdf
This deals specifically with diesel fuel used in boats

See also: BP Australia - Fuel News Topics
http://www.bp.com.au/products/fuelnews/topics.asp
Including “Common Diesel Problems”
(1) http://www.bp.com.au/fuelnews/ADF0907.pdf
(2) http://www.bp.com.au/fuelnews/ADF1006.pdf
(3) http://www.bp.com.au/fuelnews/ADF1107.pdf
and more ...

[captain323]

GordMay- I am confident I am out of compliance with one commandment, as I suffer from a high temp reading on my Volvo Penta(MD11c). Up to the water pump receives the intake water. I checked the RWater filter, clean, and replaced the impeller. Running in neutral, I run at approx. 140 degrees. As soon as I engage the drive, I lose water intake, as evidenced by the lack of water coming out of the exhaust pipe, and the temperature shoots to the danger zone. what I have yet to check(which I will) is a) line from water pump to resevoir/injectors, exhaust pipe and hose strength. By the strength i mean if a hose is old, it could collapse under the suction from the motor and close off the water flow. Any thoughts are greatly appreciated. I have read many of your posts on sailnet, and was glad to find you here. Don't let my latter compliment influence your response!!!

[GordMay]

I’m befuddled (but not Bumfuzzled) by your loss of water intake when transmission engaged. I suppose you could crack the R/W Filtre/Strainer open or loosen the supply hose at the Pump barb, and confirm that there is “no flow”.
I don’t know of any connection between the transmission and the engine cooling system. The only link I can think of would be forward motion.

Can anyone explain how getting way on might affect his water intake?

[capt lar]

i have experienced some strange backflow and siphon problems, but not at such low speeds. engage at the dock to eliminate the possibility.

[Alan Wheeler]

Hmmmmm, how interesting.
Well firstly, the water to the transmision will be for the transmision oil cooler. That won't cause a water starvation when put in gear though. Well not unless you have a problem with water in the trany oil, but you would know about that rather quickly.
So You have fitted a new impellor(that rules it out) so first you need to ensure you have a good drive to the pump. Is it belt or shaft driven? Check belts are of correct tightness.
Now go to the other end, the hose into the exhaust riser. Check that you have water flow there, BUT MOST IMPORTANTLY, check if you have water pressure. The pressure is going to be the telling point I think.
OK, so here is my thought as to the problem. For some reason, there is poor pressure. In Neutral, there is not enough exhaust pressure to be of concern. But under load, the exhaust pressure will dramaticaly increase. This may overcome the water pressure and reduce or even stop the water flow. Also check you have a clear exhaust flow, but I doubt that just a blocked exhaust would over come a good water pressure. I think you would have issues with exhaust components and engine running if back pressure were that high.
If you have poor water pressure, then the pump becomes the suspect again. Check proper belt tension and that the belt5 is OK and not slipping on the pulley. Check the pulley on the pump shaft. You should have a keyway or grubscrew. It's possible the pulley is spinning on the shaft.
Eliminate those things, and if still no good, come back to the BB and ask again.
Oh and you can safely do this at the dock. Make sure you tie up well with springs and you will safely be able to place the boat in gear and rev away to your hearts content. Don't panic, if you take the dock with you, then it wasn't strong enough to be worth a damn anyway.

[captain323]

I want to thank you all for your expedient respones. I have my list, inclusive of all your suggestions, which I will check out. I will report back my findings. Fair winds.

[captain323]

Spent another beautiful day on the ball attempting to run through all the suggestions. I doubled checked the impeller. Nothing. Then, I headed towards the thermostat and found that to be a rust bucket. So, that was replaced with the correct penta part #. Ran the engine again in neutral, and still the temp climbed up beyond reason. I have to do some more homework, as there appears to be a by-pass set up(intake runs to the lower 1/2 of the thermostat housing. There is another hose on the top of the housing that makes a U-turn and eventually feeds to the exhaust. I am thinking this is the by-pass when the engine doesn't require as much water as is coming in from the intake?--the last part being my best jr. cruiser guess). I am beginning to question if water is getting into the engine at all, or being a salt-water cooled, if the injectors are gunked up with sediment. I am also planning to take a swim to check the R/Water intake thru-hull for growth, as we are in a cove with low tidal flushing.
Any more thoughts would be appreciated...'Tis much better to be in the bay, than the mooring ball. Cheers, Joe

[Alan Wheeler]

Arrr, Salt or "Raw" water cooling. Sorry, I didn't read that in the initial post.
OK, sediment won't be a problem with injectors, as cooling has nothing to do with injectors, so don't go there.

The "by-pass feature is exactly that. This is what the thrmostat controls. Personally, I don't like raw water, especially Salt water, in engines that have a thermostat. Actually I don't like salt in engines full stop, but it has been done for many years. The Thermos are usually Brass and sometimes plated and are within a cast engine housing. You will (should,errr Must) have an Engine anode in the system, make sure it is replaced regularly. But thats a side track.
So back to the cooling. With the engine cold, the stat is closed and all raw water is sent to the exhaust. The engine heats the water within it untill the stat opens and allows the cooler water to flow into the engine and start lowering the engine temp. The thermostat finds a happy medium of water being bypassed and water flowing into the engine to cool.

Here's a question, when the thermostat was out, how much gunk was in the water system underneath the stat's seat? If you are in a very dirty water environment, it is possible sediment and rust is sitting in the water galleries around the engine and stopping it from cooling efficiently.
OK, next step. It is most likely, you have two pumps. One is the rubber impellor pump for raw water, but on the front of the engine, you most likely have an engine circulating pump. This is driven by a belt around the pulleys and will be somewhere close to your thermostat. Most likely directly below it and maybe in the same bolt on housing assembly as the stat was in. Take the belt off the pulley and give the shaft a wobble. There should be no or very little sidways movement. If there is a lot of movement, then your water pump bearing has failed. These bearings are just a bronze sleeve usually and major wear can stop the pump from working efficiently. Not to mention that it can leak and then most famousely, just fail compleatly. Oh and check the baelt for correct tension.
But I would lean towards the engine water cooling galleries as the most likely suspect. Take the outlet of the impellor pump off and put a fresh water hose into it. (you will need a hose at the dock
Turn it on and let a good flow of water run through. Now take the thermostat out and refit the housing and block the bypass, to ensure water MUST run through the engine before it is exhausted. Turn on a really good flow and see if that stirs up the gunk. Run untill clean. On land when I clean engine cooling systems, I run compressed air in as well as the water pressure. The air bubbles act as a stirring agent and flushes out all the rust and crap.
IMPORTANT: You MUST provide a way for the water to escape from the exhaust system, or it will back up and flood the exhaust, with the worst possible scenario, flooding back into the engine cyclinders, which isn't good.
Let us know what you find and good luck.

Just thought would throw my stone wheel advice out there. I think Wheels covered most everything, but the raw water intake being clogged with marine growth is the most common culprit. Another thing you might check is your raw water intake hose. could it be interfering with the shift mechanism on the gear box?
As for the cure for the intake, close the seacock, remove the hose at the pump end, and using a cheap fitting from the hardware store attach a garden hose to blow water back out the intake. Keep the fittings to run the flush the other way to flush your engine once and a while and you will preempt a number of problems.
On review, I noticed you said you were at a mooring. If you have access to a maintenance dock, you are set. If not, you may want to dive on the intake..

[captain323]

Good afternoon. Thanks to the input received on this board and a trip to a mechanic we have been off the mooring ever since. This was a real blessing as we had one of the better labor days in buzzards bay. What was clean: r/w intake(took a dive), hose thru strainer to water pump, and that's IT. Turns out...a fin on the impeller(usually has six, the one I removed had five-an obvious clue) was stuck in the water pump feeder tube. Next was the gunked up stat housing prohibiting the stat from being set properly. Next was a complete cluster of rust/sediment in the intake/exhaust lines. Upon further discovery we saw the PO ran the r/w hose to the water heater. Closed that loop off. The yard ran a solution(hydrocloric acid, I believe) through the system. Cleaned the prop and shaft, and voila, motoring right along. Heading to the Vineyard this weekend. Thanks again!!!!!

[Alan Wheeler]

Well I am glad of two things. One is that you should now have a engine keeping cool. And two, that you didn't just do one thing and stop, but you went right through the system. Very thorough and hopefully all those little nasty surprises are out and gone.