Engine Question

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2ndwish

Hi All- Went to start the engine today and an odd thing happened. Wanted to see if anyone else has had this experience...
Engine was a little slow in starting (that's not the mystery), but when it kicked in, it ran for about 1 second and stopped (the mystery). Repeated (cranked for just a couple of seconds).did it again. Third time, I kept the starter depressed for a second or two after the first combustion occurred, and then the engine ran. The engine started just fine after the sail, without the shenanigans. I haven't seen this behavior before. Cold weather thing? Something to be concerned about?. BTW, engine is an M25XP , ~1100 hours

Todd

David Sanner


Cold weather probably didn't help but there are lots of factors that
could have combined to make this start different from a typical one.
Any idea how strong are your batteries were?  (kept on the charger?)
How long did you press the glow plug for before starting?
How much throttle did you have turned on?

Poor compression, cold engine, not enough glow plug
and slow cranking can inject but not burn the fuel.
When one cylinder does fire it can seem to start up, but not enough
to keep going once the excess fuel burns out of that cylinder. 
Meanwhile while fuel still pumps into the other cylinders. 
Each time you try to start it warms up a bit and has
a better chance to keep going with the next starter bump.

If you saw a lot of smoke coming out once it finally
got underway I wouldn't be too concerned, especially
since it ran fine afterwards.

If this is a consistent problem the "running / not-running"
behavior is very binary with little unburnt fuel (smoke) coming
out of the exhaust then you might have something more
significant going on.

My thinking is that you have nothing to worry about but...
you can always get a compression check,  glow plug test,
injector test, to be sure.  I would start with a battery and
cable check if it happens again.




David Sanner, #611 1988, "Queimada" San Francisco Bay

Stu Jackson

B4 you start worrying about your engine, you may want to consider Reply #24 from the Critical upgrades topic:  http://c34.org/bbs/index.php/topic,5078.15.html

Don't know if you have done so, yet.  If so, and U still have problems, Dave's right, start checking the mechanical things.
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

2ndwish

Thanks for the advice. The boat certainly was sluggish in starting, ie not enough cranking power, but I thought it was unrelated to the "fire and die" aspect. Maybe they were related. I didn't notice a particularly large amount of smoke coming out, but the description of one cylinder firing and it not having enough to keep going sure sounds like what might have happened. I checked but did not replace the fuse holder when I did the wiring harness upgrade.

The slow cranking had been a problem on 2nd Wish for a while. When we replaced the harness this summer, we cleaned and tightened most of the battery terminals as well. The cranking improved dramatically. The fact that it seems to have returned to it old ways might indicate that something has worked loose or requires cleaning (we used Boeing terminal moisture inhibitor, perhaps it has a limited service life?).

We'll just keep monitoring the problem and see whether it continues.
Thanks for the advice
T

Ron Hill

Todd : From your last discreption it sounds like a cranking problem, although glow plugs can not be counted out.  Usually if you can get one cylinder of a diesel to fire the others will also ignite.

You mentioned better cranking after cleaning and tightening battery cable connections.  I'm a crimp and solder person so you can already guess at my suggestion.  Solder all battery cable connections (+ & -) from the battery, to the selector switch, to the battery solenoid positive and engine ground negative.
If you have a starting battery separated from the house bank on selector switch, try starting in the ALL position.

It really sounds as though it's a poor connection or a poor battery.  So try those ideas first. 
Hope this helps solve your problem.   
Ron, Apache #788

2ndwish

Ron- How do you solder the heavy gauge wires? A torch? Flux? What do you do to protect the the insulation?
Thanks in advance.
T

Craig Illman

#6
I heated the far end of the lug with a propane torch. When it's hot enough, the solder will flow into the lug around the tinned wire. I then protected it with heat shrink tubing for battery cables. The insulation on the stripped wire didn't get significantly impacted.

Craig

Ken Juul

You have to use a torch of some kind, too much metal needs to be heated to use a soldering iron.  Another method, I did not pretin my wires.  I cut the insulation back about double the length of the insertion into the lug.  Crimp the wire in the lug.  Pointing the flame toward the end of the wire/lug so it doesn't burn the insulation, heat the wire/lug and let the solder flow into the lug, as it fills slowly heat the wire back toward the insulation to get the solder to flow up the wire into the insulaton.  Cover all exposed wire with heat shrink.
Ken & Vicki Juul
Luna Loca #1090
Chesapeake Bay
Past Commodore C34IA

Ron Hill

T : You can purchase a "mini" torch and West marine for about $15-20.  Use this to solder connections of #8 wire and larger.  Otherwise use a 1500W electric gun.

Make sure that you use radio/resin core solder and crimp first.
 
If the connection is an open end, just heat up the connector and the solder when it melts, will flow toward the heated side. 
If you have a closed connector here's what I do : drill a small hole (size of the solder dia.) in the end of the connector by the ring end.  Heat the connector and as you are heating take the solder and feed about 1" of it into the hole.  Make sure that you let the connector/ion cool before you move it or you could wind up with a "cold solder joint".

I have a small fire resistant blanket (12"x12"?) that I can place under the item to be soldered or use it to protect other items from the heat.

This is only a "quick & dirty" on the how to of soldering.  With a little practice it'll become easy. 
Ron, Apache #788

Mike and Joanne Stimmler

What kind/brand of crimping tool do use. Some are pretty expensive.
Mike and Joanne Stimmler
Former owner of Calerpitter
'89 Tall Rig Fin keel #940
San Diego/Mission Bay
mjstimmler@cox.net

Stu Jackson

Hi, Mike, how's it going?  We just hauled, things look great, splash-back tonight.

I've had success with the "bang it with a hammer - jaws of death" silver crimper for larger stuff - lotsa #4 and #2 wire on Aquavite.

All other wiring is done with an Ancor ratcheting crimper.  Maine Sail has a good discussion on his website.
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Ron Hill

Mike : I use a hand crimper for the small gage wire (don't recall the name Kline?) and the hammer crimper for the larger stuff.  The only difference is with the "hammer crimper" I don't use a hammer.  Found that a vice-grips work much better.
Ron, Apache #788