YANMAR starting problem

BCC Forum
1

While in the Bahamas this spring we had intermittent starting problems with our Yanmar 3GM30F. When running it sounded and ran smoothly as per normal, but would sometimes refuse to start.
Symptoms were:

  1. Push starter button, starter engages, engine turns over less than a complete revolution and “locks up”.

  2. Check battery voltage, no problem, 12. 8 volts.

  3. Open all three compression release levers. #1 lever is hard to open all the way, seems to run into resistance and with difficulty can be induced to almost click into place.

  4. Push starter button again, engine will “bump” but not turn over – but #1 lever pops closed and #2 and #3 stay open.

  5. Test solenoid with a jumper cable, it engages normally, ditto for starter, which spins freely when jumped without the solenoid actuated.

  6. Removed starter, had a local shop test it and all was ok.

  7. Turned engine over by hand several revolutions using a wrench on one of the belt pulleys.

  8. Try to start, nothing doing, then repeat the process a few times.

  9. After several repetitions the engine turns over and finally starts with more smoke than usual, and then runs normally.

  10. Starts and runs normally for a few days and then the process begins again – will not start, and sooner or later decides to start and runs perfectly normally.

  11. So in late June we hauled at Tiger Point Marine in Fernandina Beach to get a bunch of maintenance work done (including a leaking aft water tank!) and had their Yanmar mechanics check out the engine. Pulled the valve cover and all looked normal. Replaced the wet exhaust elbow, waaaay overdue, thinking that it might be obstructed and contributing to the starting problem. It was somewhat clogged but not entirely-so. One thought was that a restricted elbow might cause enough back pressure for water to get into the manifold and lock up a cylinder. Possible?

Mechanic says the engine starts and runs normally now, but of course with an intermittent problem I am concerned that the problem may lie elsewhere, ready to recur at the worst possible moment! Now am home in Maine, planning to go back to Itchen in a month or two.
Suggestions welcome,
Thanks,

2

Scott,
If water was getting back in the cylinders, it seems like you’d see evidence of it in the lube oil. I’ve never had water in the cylinders of our 1988 3GM30F (knock on wood!), but from what I’ve heard, it’s not easy to get it out. I hear tales of removing each injector and siphoning out the water through a straw?? Anyway, it sounds like your engine runs just fine, and the problem is just with starting.

Did the compression lever difficulty persist? Did the Yanmar mechanics fix it? I wonder if the engine acted up for the mechanics?

Is it possible that the problem could be caused by not enough current getting to the starter motor? The battery voltage may be OK but there could be resistance in the wiring that reduces the current flow to the starter motor. Is your starter battery in good shape?

I had trouble starting our 3GM30F several years ago and decided the wiring and connections between the solenoid, the key switch and the starter switch needed to be redone with bigger wire. There were too many connections to the back of the key switch. That seemed to improve starting (in warmer weather). It sounds like this circuit works OK for you, and that the big cable to the starter motor from the starter battery might not be delivering enough current to the starter motor?

I’m not a mechanic, so I’m just flailing around, but another possibility might be that your starter motor has some bad spots (in the commutator or ?) and is only occasionally able to get the job done? Starter motors do wear out and some folks do carry spares (we didn’t when cruising off-shore). It sure sounds like your problem is somewhere in the start battery to starter motor circuit.

Our engine does have over 5,000 hrs on it and it doesn’t like to start in cold weather (temps in the 50’s). I’m guessing it’s because there’s wear in the cylinder walls and piston rings, and it’s hard to get a seal and compression up until things have warmed up a bit. Cranking for 5 or 10 seconds will usually get it started. I’m grateful that the problem is consistent, not intermittent, like yours. We don’t use the boat in the winter here in Seattle so it hasn’t been a problem for us so far. The warm wx in the Bahamas should help you with this sort of problem.

It must be frustrating to not have the boat where you can deal with the problem yourself. We used to have a diesel mechanic and BCC owner as a frequent contributor on the forum but unfortunately he sold his BCC. You could try and pick the brain of your local Yanmar (or?) diesel mechanic. Good luck!
Dan Shaula (edited to correct engine hours)

3

svshaula Wrote:

Scott,
If water was getting back in the cylinders, it
seems like you’d see evidence of it in the lube
oil. I’ve never had water in the cylinders of our
1988 3GM30F (knock on wood!), but from what I’ve
heard, it’s not easy to get it out. I hear tales
of removing each injector and siphoning out the
water through a straw?? Anyway, it sounds like
your engine runs just fine, and the problem is
just with starting.

Did the compression lever difficulty persist?

Not sure, will ask next time I call the yard, I did tell them about it when I gave them the job.

Did

the Yanmar mechanics fix it?
No mention of it from them one way or the other.

I wonder if the

engine acted up for the mechanics?

No, they said it started and ran normally – but given that it was an intermittent problem I am not particularly reassured!

Is it possible that the problem could be caused by
not enough current getting to the starter motor?
The battery voltage may be OK but there could be
resistance in the wiring that reduces the current
flow to the starter motor.

Well, the solenoid engages normally and its relay contacts are not accessible for inspection or cleaning like many oldtime solenoids, so I bought a new backup solenoid and will swap it with the existing one if the problem recurs.
Is your starter battery

in good shape?

Yes, good strong batteries and the problem existed when using either the house bank or the starter battery.

I had trouble starting our 3GM30F several years
ago and decided the wiring and connections between
the solenoid, the key switch and the starter
switch needed to be redone with bigger wire. There
were too many connections to the back of the key
switch.

Yes, this is a significant issue with the Yanmar instrument panel mounted low in the cockpit well – lots of access for salty water there under normal offshore conditions – and notably so when we filled the cockpit one night running from the Abacos to Newport a couple years ago! So I did take it apart when I got to Fernandina and cleaned some nasty green gunky connections. But these only affect the tachometer, the warning lights and power to the solenoid so far as I can tell.

That seemed to improve starting (in warmer

weather). It sounds like this circuit works OK for
you, and that the big cable to the starter motor
from the starter battery might not be delivering
enough current to the starter motor?

Have good clean tight connections and a short run from battery to solenoid relay and thence to the starter. The ground cable was so-so and I retightened it well but the problem continued.

I’m not a mechanic, so I’m just flailing around,
but another possibility might be that your starter
motor has some bad spots (in the commutator or ?)
and is only occasionally able to get the job done?
Starter motors do wear out and some folks do carry
spares (we didn’t when cruising off-shore).

Yup, I discussed this with the starter shop guys and they saw no problem. I do have a spare on board and will swap them if the problem continues to eliminate this possibility.

It

sure sounds like your problem is somewhere in the
start battery to starter motor circuit.

Has been my first guess all along but hard to see where it can be, given that all the elements check out ok thus far. Could possibly be a starter bendix gear to flywheel ring gear interference problem but hard to check that out visually.

Our engine does have over 50,000 hrs on it and it
doesn’t like to start in cold weather (temps in
the 50’s). I’m guessing it’s because there’s wear
in the cylinder walls and piston rings, and it’s
hard to get a seal and compression up until things
have warmed up a bit. Cranking for 5 or 10 seconds
will usually get it started. I’m grateful that the
problem is consistent, not intermittent, like
yours. We don’t use the boat in the winter here in
Seattle so it hasn’t been a problem for us so far.
The warm wx in the Bahamas should help you with
this sort of problem.

Yes, if you look into the archives many years ago Itchen had a hard starting and then a loss of coolant issue which turned out to be due to a very slightly warped cylinder head and leaking head gasket. Planed the head, replaced the gasket and it went from 20- 30 seconds to start in cold weather to 3 to 5 seconds! It’s a tough little engine and most problems are more easily identified and fixed than ours of the moment, alas.

It must be frustrating to not have the boat where
you can deal with the problem yourself. We used to
have a diesel mechanic and BCC owner as a frequent
contributor on the forum but unfortunately he sold
his BCC. You could try and pick the brain of your
local Yanmar (or?) diesel mechanic. Good luck!
Dan Shaula

All good advice, thanks,

4

In your original post, you said:
“5. Test solenoid with a jumper cable, it engages normally, ditto for starter, which spins freely when jumped without the solenoid actuated.”

Were you able to do this test when the engine wouldn’t start? In other words, bypass the key switch and the push-to-on start button? If your Yanmar panel is still in the cockpit well, the key switch and start button no doubt got some salt water along with the tach and buzzer when you filled the cockpit well. That can corrode their contacts, but also corrode the wires, coating them with not visible non-conducting black copper oxide. It’s amazing how salt water wicks up stranded wire.

I had this problem due to the panel’s low position in the cockpit well, but also due to a lousy gasket on the panel. Also the plastic panel wasn’t stiff enough to form a good seal. I ended up moving the panel’s components down below, one by one. First the buzzer, then the kill cable, then the key switch, and finally the start button. The only thing left is the tach and 2 after-market gauges (oil pressure and water temp). Last winter I finally got rid of the panel and replaced it with some 3/8" plywood, epoxied and painted.

Is it possible to correlate the intermittent problem with the weather at all? Maybe higher humidity? If so, that might point to corrosion in the wiring? Just a thought.

Dan Shaula

5

In your original post, you said:
“5. Test solenoid with a jumper cable, it engages normally, ditto for starter, which spins freely when jumped without the solenoid actuated.”

Were you able to do this test when the engine wouldn’t start? In other words, bypass the key switch and the push-to-on start button? If your Yanmar panel is still in the cockpit well, the key switch and start button no doubt got some salt water along with the tach and buzzer when you filled the cockpit well. That can corrode their contacts, but also corrode the wires, coating them with not visible non-conducting black copper oxide. It’s amazing how salt water wicks up stranded wire.

I had this problem due to the panel’s low position in the cockpit well, but also due to a lousy gasket on the panel. Also the plastic panel wasn’t stiff enough to form a good seal. I ended up moving the panel’s components down below, one by one. First the buzzer, then the kill cable, then the key switch, and finally the start button. The only thing left is the tach and 2 after-market gauges (oil pressure and water temp). Last winter I finally got rid of the panel and replaced it with some 3/8" plywood, epoxied and painted.

Is it possible to correlate the intermittent problem with the weather at all? Maybe higher humidity? If so, that might point to corrosion in the wiring? Just a thought.

Dan Shaula

6

svshaula Wrote:

In your original post, you said:
“5. Test solenoid with a jumper cable, it engages
normally, ditto for starter, which spins
freely when jumped without the solenoid
actuated.”

Were you able to do this test when the engine
wouldn’t start? In other words, bypass the key
switch and the push-to-on start button?

Exactly so, with a jumper from a hot source to the solenoid to see if it would engage the solenoid, which it did, and the bendix engaged but the engine would not turn over.

If your

Yanmar panel is still in the cockpit well, the key
switch and start button no doubt got some salt
water along with the tach and buzzer when you
filled the cockpit well. That can corrode their
contacts, but also corrode the wires, coating them
with not visible non-conducting black copper
oxide. It’s amazing how salt water wicks up
stranded wire.

Indeed. And though I had time to clean the contacts I did not strip back the wires so doubtless there is still need to do some resistance checking and rewiring. The partial cleanup did restore the intermittent alternator and oil pressure alarms to normal function.

I had this problem due to the panel’s low position
in the cockpit well, but also due to a lousy
gasket on the panel. Also the plastic panel wasn’t
stiff enough to form a good seal.

Yes to all the above in our case, one of the few “design issues” in a typical BCC, and not a problem until salty water dribbles back behind the panel!

I ended up

moving the panel’s components down below, one by
one. First the buzzer, then the kill cable, then
the key switch, and finally the start button. The
only thing left is the tach and 2 after-market
gauges (oil pressure and water temp). Last winter
I finally got rid of the panel and replaced it
with some 3/8" plywood, epoxied and painted.

I like your solution. Kill cable? Do you mean the on/off key switch? I do like having the engine fuel cutoff pull cable close at hand. I have been considering various ways to eliminate this known corrosion problem whilst at least still being able to see the tachometer and very loudly hear the oil and amp alarms. The panel placement also limits the good locations available for harness tether pad eyes when coming up from below and clipping in.

Is it possible to correlate the intermittent
problem with the weather at all? Maybe higher
humidity? If so, that might point to corrosion in
the wiring? Just a thought.

Hard to say, but I did not notice any obvious correlation, but worth considering

Dan Shaula

Thanks,

7

You seem to have done a lot of good investigation, and it’s frustrating that it’s not clear what the problem is. I wonder, you say:
“5. Test solenoid with a jumper cable, it engages normally, ditto for starter, which spins freely when jumped without the solenoid actuated.”

In thinking about the above, the problem seems to lie between the starter motor and the flywheel. I wonder if you need a new (or rebuilt?) starter motor? What are the symptoms when a starter motor starts to go? I know Yanmar starter motors aren’t cheap, but off-shore cruisers who can afford it do carry a spare. Maybe that’s the cost of nursing and old engine through the boondocks? Hmmm.

I replaced the buzzer several times and it went out again in the Marquesas. I went to a garage and bought a motorcycle turn-signal buzzer and located it inside and starboard, near the aft, inboard, upper side of the quarter berth entrance. We don’t have any trouble hearing it in the cockpit.

I also got annoyed at having to replace the morse control cable that shuts off the fuel. Salt water would get in at the panel and corrode the guts. I mounted a small ss right angle piece on the engine and bolted on a small metal pulley, and ran a stranded wire cable (abt 1/16" diam.). The wire is attached to the shutoff lever, runs through the pulley, then up through a very small hole drilled in the 3" wide formica covered ledge, and up to the brass tubing that the ladder swings on. The wire loops around the tubing just outboard of the ladder and is fastened back on itself. It’s very easy to reach this wire loop from the cockpit, and can be done easily by feel. I guess it’s a bit crude, but it’s simple and it works every time with no friction.

I mounted the key switch and the starter momemtary-on push switch under the bridge deck. They’re mounted on the vertical, fore & aft 3/8" plywood that extends above the old “wet locker”. I think BCC’s have had a number of different cabinetry arrangements in that area. I got rid of the wet locker and expanded the engine compartment.

Dan Shaula BCC 59 (1981)

8

svshaula Wrote:

You seem to have done a lot of good investigation,
and it’s frustrating that it’s not clear what the
problem is. I wonder, you say:
“5. Test solenoid with a jumper cable, it engages
normally, ditto for starter, which spins freely
when jumped without the solenoid actuated.”

In thinking about the above, the problem seems to
lie between the starter motor and the flywheel.

Agreed. Back in the days when I ran high-mileage old cars and had a workshop full of car tools, one infrequent but known issue had to do with a chipped or burred or misaligned starter pinion gear or flywheel ring gear which always worked ok except after they came to rest where pinion and ring gear did not mesh happily. But this pinion gear looks good, and the ring gear is hard to check out without a lot of careful and difficult flywheel rotation while peering into the starter pinion hole. The classic work-around is to rotate the engine a bit to change the pinion to ring gear mismatch, and then all should go well. That did not seem to work for me in this case. The mystery was that after an unpredictable number of unsuccessful attempts, sooner or later (usually later) it would start as per normal.

I

wonder if you need a new (or rebuilt?) starter
motor? What are the symptoms when a starter motor
starts to go? I know Yanmar starter motors aren’t
cheap, but off-shore cruisers who can afford it do
carry a spare. Maybe that’s the cost of nursing
and old engine through the boondocks? Hmmm.

Actually I do have a spare (one I had rebuilt after I had replaced it with a new one) and if the problem recurs will see if it does any better.

I replaced the buzzer several times and it went
out again in the Marquesas. I went to a garage and
bought a motorcycle turn-signal buzzer and located
it inside and starboard, near the aft, inboard,
upper side of the quarter berth entrance. We don’t
have any trouble hearing it in the cockpit.

I also got annoyed at having to replace the morse
control cable that shuts off the fuel. Salt water
would get in at the panel and corrode the guts. I
mounted a small ss right angle piece on the engine
and bolted on a small metal pulley, and ran a
stranded wire cable (abt 1/16" diam.). The wire is
attached to the shutoff lever, runs through the
pulley, then up through a very small hole drilled
in the 3" wide formica covered ledge, and up to
the brass tubing that the ladder swings on. The
wire loops around the tubing just outboard of the
ladder and is fastened back on itself. It’s very
easy to reach this wire loop from the cockpit, and
can be done easily by feel. I guess it’s a bit
crude, but it’s simple and it works every time
with no friction.

I mounted the key switch and the starter
momemtary-on push switch under the bridge deck.
They’re mounted on the vertical, fore & aft 3/8"
plywood that extends above the old “wet locker”. I
think BCC’s have had a number of different
cabinetry arrangements in that area. I got rid of
the wet locker and expanded the engine
compartment.

All interesting, and I will eyeball Itchen’s layout to see what might work for us.

Thanks!

Dan Shaula BCC 59 (1981)

9

Hi Scott how ya doin, it was great to see you in Manjack Key this spring, and what a delight to have the two boats together… I was pooped crossing the gulf a few years ago and my instrument panel got a good wash, I too, am also nervous about the electrics, maybe have to move them downstairs. Trust you r well.

10

I installed a new instrument panel and gasket along with a new lexan cover on Galatea.

11

Here’s a picture of my new instrument panel…

image.jpg
image.jpg2048×1536 849 KB

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