Larry wrote:

Stephen Trapani wrote in
:


It's raw water.




Sorry............................Yecch.


Any water passage I've seen in the engine still looks completely uncorroded.

Stephen

Try this:

Get a plastic milk jug, cut it open so you can wipe it clean with a
rag. Put fuel in it. Get some clear tubing from Lowes or Home Depot.
Run the tubing to the fuel fitting on the inlet to your fuel pump.
Fill the tubing with fuel and allow it to siphon the fuel from the milk
jug. Start your engine. If it does not lose power as it did before,
then suspect your fuel filtration.
The Yanmar mechanical fuel pumps seem to go bad all the time. I got an
electrical pump from JC Whitney that I put in series with the
mechanical one. It is wired to the starter so it always provides low
pressure to the engine. It keeps the engine primed.
It sounds like you have both engine timing and fuel problems. Valve
timing is easy to set on this engine. Injection timing is a little
harder but a COMPETENT mechanic can do it. You can do it yourself if
you can follow the directions in the service manual.

For cold starting, use the decompression levers. Relieve compression
on one or both cylinders, get it turning then put in compression, this
will get things lubed well and moving before you are trying to work
against the compression.

You might also check your fuel return line. If it is blocked, you can
have problems. When you are priming the engine, remove it from the
fitting on the injectors, blow into it (a little diesel fuel in your
moth will not hurt you) to see if it is clear.

Take the exhaust hose off the exhaust manifold and run the exhaust into
a 5 gal bucket This will fill your cabin with smoke so be careful but
the idea is to see if your muffler is clogged..

You really need to get a service manual. Try Mastry Marine in St.
Petersburg, FL for it.

Stephen Trapani wrote:

Yes, but it isn't it a very good idea to instruct the mechanics to ask
you what to do you when they know what's wrong and tell you what they
think should be done and what it's going to cost?

Huh? It should be normal without instructing.

And at that point when they ask you that, isn't it a good idea to have
some idea of the likely problems and options?

They should have more of these than you do if they have repaired
hundreds of boats to your one or three. It's certainly a good idea to
challenge & contribute to their ideas in accord with what you do know,
and certainly to approve/disapprove the course of action, because
ultimately you are directing the work. This is not the same thing as
dictating what the whole problem may entail & the specific details of
how to go at it. If you are capable of the latter (and a few are), you
should give them a spec up front. But what you do know is also not the
same thing as what others may try to deduce unseen from your best
attempts at description & tell you. This is the nexus of the matter.

I know I've been in these
kinds of situations before with exactly this boat, I've regretted not
having enough information, and I've loved every time I'd previously had
advice from experts like some of the guys here, and been able to either
trust the mechanic to go ahead with what he thinks, or stop him!

Indeed there are times to stop or even discharge him/her/them. But we
have come full circle to the problem of their competence & your
selection of them, in a case of less-than-complete knowledge of the
problem & all applicable repair methods.

I'm simply trying to make the point that a good one has seen & solved
such problems hundreds of times more than the best owner, and that with
the right parties it is a dance of wielding & balancing authority over
(what is supposed to be) superior experience & abilities. The yard's
primary job is to relieve you of as much money as possible at the least
burdened cost, and yours is as a conservator of funds & dictator of the
end results. Yards are very expert at diminishing the bank accounts of
those who micromanage with various interruptions & ideas and get them
to pursue or change course in more than one direction. Just mentioning
another idea to an onboard mechanic in a boatyard can increase your
bill by 2 manhours & tap productivity by twice that, by getting him to
"go find & talk to his manager about it." The time for all "how-to"
ideas to be hashed through & resolved is before anything (including the
ticking of the money clock) starts, leaving only any emergent "off
course" situations for interfacing & dealing with during execution.
Since the latter are always found by the yard, that is what is meant by
having them come to you, not "instructing." And when they do, you both
will already have pre-discussed options from your initial dealing,
which will save even more time unless a major new problem is unearthed.

This seems all the more relevant in a typical small boatyard or small
marine mechanic situation where the worker may be punching in/out on 4
different boats in the same day, and in a very real sense you are also
competing with other owners' interests to keep your productivity higher
(and your bill lower) than theirs. In such a siutation there will be
at least one boat where significant worker time was allocated that
didn't do ****-all, you may be certain. :-)

With good people, the healthy & ongoing distrust should be financial,
not technical. If you get good at this, you will have the lowest bills
and the highest respect, and they will remember you for years and
befriend you as a prime customer. Excellent repair people care even
more about their pride than the money, and it is well-earned with years
of deckplate innovative solution thinking & living out the results.
Minimize this subtle but powerful fact at your peril. :-)

It is true that repair excellence is getting rarer by the day in the
entire marine world & has been for 40 years. I'm trying to help you
deal more productively with the superior goods, if you find them -
which is always the hardest part of the task. Trying to educate the
inferior goods yourself won't make them any better, and will only give
them split responsiblity to point at as soon as convenient - even if
you were "right."

HTH

Dave wrote:

Sure glad I didn't follow this advice this spring. Asked Minneford's to
replace the muffler and adjust the stuffing box, as I wouldn't have time for
the stuffing box before leaving on Sat. Fortunately, I didn't trust them and
came an extra couple of hours early. Muffler replaced, nothing done to the
stuffing box, and no mechanic in sight.

Rather typical - multi-tasked yard timing is not owner timing & often
such an item is done in the last hour.

I adjusted the stuffing box myself.

Relieving them of responsbility for any results.

I'm curious what the bill will say.

You didn't sight it before leaving? Delay is a bad idea - their memory
gets "creative." I'd be more concerned with this business practice
than the minor inconvenience of twisting a couple of nuts or installing
another packing ring, unless you own preferred stock in Minneford's.
:-)

Hey, thanks for the advice! A question or two.

wrote:
Try this:

Get a plastic milk jug, cut it open so you can wipe it clean with a
rag. Put fuel in it. Get some clear tubing from Lowes or Home Depot.
Run the tubing to the fuel fitting on the inlet to your fuel pump.
Fill the tubing with fuel and allow it to siphon the fuel from the milk
jug. Start your engine. If it does not lose power as it did before,
then suspect your fuel filtration.
The Yanmar mechanical fuel pumps seem to go bad all the time. I got an
electrical pump from JC Whitney that I put in series with the
mechanical one. It is wired to the starter so it always provides low
pressure to the engine. It keeps the engine primed.
It sounds like you have both engine timing and fuel problems. Valve
timing is easy to set on this engine.

My buddy has a 2QM20 repair manual. It says the valve clearance should
be .15mm. My mechanic guy set it to that. Is that right? where can I get
the setting for the 2QM15?

Injection timing is a little
harder but a COMPETENT mechanic can do it.

We took it in to a shop who set both injectors to 100.

You can do it yourself if
you can follow the directions in the service manual.

For cold starting, use the decompression levers. Relieve compression
on one or both cylinders, get it turning then put in compression, this
will get things lubed well and moving before you are trying to work
against the compression.

You might also check your fuel return line. If it is blocked, you can
have problems. When you are priming the engine, remove it from the
fitting on the injectors, blow into it (a little diesel fuel in your
moth will not hurt you) to see if it is clear.

Take the exhaust hose off the exhaust manifold and run the exhaust into
a 5 gal bucket This will fill your cabin with smoke so be careful but
the idea is to see if your muffler is clogged..


Sorry for the dumb question, but how does this tell me if it's clogged?
Oh, it runs better after I take it off? Why in a bucket? I can see the
exhaust with water coming out below the transom.

Thanks!

--
Stephen

-------


For any proposition there is always some sufficiently narrow
interpretation of its terms, such that it turns out true, and
some sufficiently wide interpretation such that it turns out
false...concept stretching will refute *any* statement, and will
leave no true statement whatsoever.
-- Imre Lakatos

In article ,
Stephen Trapani wrote:

Jere Lull wrote:

The hard starts could also be from undersized battery or cables,

Yes, I have a low battery bank. Old batteries and it turns over
fairly slowly. Once the engine is warm, it starts in a second or two
every time.

Work on that in any case. I would make sure the battery was well
charged and the connections clean and tight before at least one cold
start, to eliminate (or confirm) the starting circuit as a problem.

A warm engine will usually start more easily than a cold one, and a low
battery's charge will improve quickly. Thus, an easy warm start doesn't
help diagnose the problem much.

The drastic power decrease after a few minutes could be a
mostly-blocked fuel filter, fuel tank pickup or vent. Change
filters, clean the bowls and see if it still happens.

I did this all once. Maybe the Racor needs changing? I had the tank
all the way out and cleaned by two mechanic friends.

The one time I had critter problems, it didn't clear up until I'd
changed the filter twice and brushed off my last one once or twice.
Even then, we couldn't pull full power until we'd motored a few hours at
low power. Lots of critter corpses fell to the bottom of the bowl as
we slowly bounced along.

I'd also suspect overheating at full power, except that the alarms
aren't going off. Any change in the reservoir level, day to day?

Reservoir?

Sorry, I forgot that the 2QM15 was raw-water. I was trying to
figure out whether you might be overheating without the alarm going
off. You have water coming out the exhaust from your other posts,
so I tend to assume you aren't overheating in 10 minutes. Any sign/smell
of overheating as you lose power? Any little things that might not seem
important?

If those steps don't solve it, I'm afraid you're looking at a
rebuild, but don't start worrying until you've exhausted
alternatives, as that's a remarkable engine from what I've heard.

Would a diesel needing a rebuild run hard for ten minutes, then lose
RPM and pushing power?

I don't believe so. Most of the time, they seem to get cranky about
everything.

What you're describing sounds consistent and repeatable. What happens if
you're not pulling high power? Do you have a drop-off if you motor at
200, 400, ... fewer RPMs? If you do, does it take longer?

And about that drop-off: Does the engine die, or will it continue to run
at the lower power for a long time? How high is that lower power? For
that matter, what are the RPMs at high power?

As I write, I also wonder: Is the stuffing box hot when you get the
drop-off?

I still primarily suspect fuel delivery. If it's not the filter, than
possibly something that's binding when the engine gets up to operating
temperature.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/