yanmar 4jh4e starting problem

[noviradio]

I am not sure that problem is resolved,because engine is started yesterday and today,real test will be after 15-20 days of sitting,I am not using glow plugs because i am not able to switch to glow position on panel,i started engine today with starter battery,house battery is not starting battery

[Howler]

If you have shore power, blow a hair dryer or other source of warm air into the air intake for a few minutes and she'll start like a charm.

[transmitterdan]

The 4JH4E does not have glow plugs as far as I know. It may have the optional heater inline with the air intake.

But I agree that the power for the starter is the main issue. And battery is the first suspect. It may have a weak cell the works well when recently charged but after 2-3 weeks the cell is not permitting full voltage. Try a different battery as a test.

[Cadence]

[QUOTE=noviradio;2531349]I am not sure that problem is resolved,because engine is started yesterday and today,real test will be after 15-20 days of sitting,I am not using glow plugs because i am not able to switch to glow position on panel,i started engine today with starter battery,house battery is not starting battery
Seems you only have an electrical problem, i am not able to switch to glow position on panel,i

[Wotname]

Originally Posted by noviradio

first i forget to say hello to everyone,thanks for good advices,starter battery is optima blue top 66ah 850ccA agm manufactured 2015 and voltage on battery is 12.7 V,I dont try to start the engine from house bank,today I checked all connections on starter motor and battery terminals and there wasnt any serious corision,but i also cleaned them and tightened.I try to start the engine and engine starts fine in 1-2 seconds.I wasnt look for air in fuel i will check another time,and also i dont make a voltage during the starting because i was alone on boat.

OK, the battery is suitable if it is still in good condition; while a newish AGM starting battery is hard to destroy, it is possible .

Unfortunately measuring the open circuit (unloaded) terminal voltage of the battery tells us almost nothing about the condition of the battery. It has to measured when under load, preferably when cranking the engine. There some other less optimal ways of noting the terminal voltage when cranking. I note that the oil pressure light and the audible alarm both extinguish while you are cranking the engine; this indicates (but does not prove) the terminal voltage is too low under load. The audile alarm returns briefly when the engine fires which also supports the idea the battery is not good.

FWIW, the audile alarm on my little Yanmar 2GM20 does not extinguish when cranking the engine over - but is does drop in volume when I use the smaller battery rather than the bigger one .

Next time take some long clip leads and clip your meter onto the battery so you can watch the voltage while cranking. If OK, then you should clip the leads to the starter motor terminals. However if you can take a crew mate with you, it will be easier than using long clip leads .

Originally Posted by Charlie

Congrats. Sounds like you have fixed the problem. I don't know why it would start better after running. ......

That is a reasonable point but I guess it is because the engine only has to turn over a revolution or two before it fires when warm and thus the delayed start slow rpm is just not noticed. A warm diesel will always start easier than a cold one

Originally Posted by noviradio

I am not sure that problem is resolved,because engine is started yesterday and today,real test will be after 15-20 days of sitting,I am not using glow plugs because i am not able to switch to glow position on panel,i started engine today with starter battery,house battery is not starting battery

Well 1 to 2 seconds is a considerable improvement on the 4 or 5 seconds so perhaps the connections were part of the problem.

If you still have a slow start in 15 to 20 days of sitting, then the battery is very very suspect.

A engine cannot tell how long it sits between starting i.e if it cold today, it will behave the same as if it was cold yesterday or tomorrow or next month but a battery is time sensitive and will deteriorate as it sits and the performance of bad battery will be noticed sooner than a good battery.

I know I am sounding like a broken record but the only test is to measure the voltages while the engine is cranking or replace the battery with a known good one.

Finally, we don't know where your are and thus we can't guess at the ambient temperatures at your location but I am assuming the ambient temperature is say 10 C or higher. If significantly lower, say around 1 or 2 C or lower, then both battery and engine will behave differently and this makes it more difficult to diagnose from afar.

Perhaps a good question is "when did you first notice the delayed starting issue, was it ever faster and if so, what has changed"?

[jimbunyard]

In addition to all the good advice above, there are these possible things to check also;


Loose starter mounting bolts.

Corrosion/rust between the starter housing and engine block.

Hidden corrosion within one or more of the battery cables or solenoid energizing wires.

Corrosion (more properly burning) within the solenoid, between the high amp contacts.

Loose solenoid, or corrosion between solenoid and starter.

Bad starter switch contacts.

Bad starter relay, if you have one.

Bad battery on/off or selector switch, if you have one.

[noviradio]

engine was always start rough(2-3)seconds in last 2 years with optima,never starts in first shot,only when it was warm.Tempereture when starting was about 10 degrees.
Today I measure the voltage on battery and starter motor during cranking,results are:minimum voltage on battery was:10.64V,minimum voltage on starter motor was:9.7V.
There are also video clips :battery-

[noviradio]

starter motor-

[Tornadosailing]

Originally Posted by noviradio

engine was always start rough(2-3)seconds in last 2 years with optima,never starts in first shot,only when it was warm.Tempereture when starting was about 10 degrees.
Today I measure the voltage on battery and starter motor during cranking,results are:minimum voltage on battery was:10.64V,minimum voltage on starter motor was:9.7V.

There's been some good advice here so far, and a little that's been off the mark.


I'll preface this by saying that I'm an ASE certified master auto tech, 20+ year auto shop owner, and sorting out electrical problems is one of my strong points.

Since the battery is maintaining 10.6 volts while cranking, I don't think it's a battery problem, but since the battery is a very easy thing to test, I would try a known good battery just to put that possibility to bed. It's also possible that your starter is dragging internally and simply not able to turn at a proper RPM. The easiest way to see this is to test the current draw that the starter is pulling. This is easy at my shop, but very unlikely that you have the test equipment available to do this on the boat. As such you're stuck with a process of elimination. If all voltage drop tests are good, replace the starter.


The first problem is the almost 1 volt drop between the starter and battery when cranking. This could be caused by internal corrosion in the cable. After you ensure that all connections are clean and the 1 volt drop is still there, suspect the positive cable. Unfortunately this can also be caused by excessive starter current draw, and the battery cable's inability to keep up with an excessive demand. A current draw test is the best way to know, but in the absence of a high current tester, you can add additional current capacity by adding an additional current path in parallel. The easy way to do this is with an automotive jumper cable. If you install a jumper cable from the battery to the starter alongside your existing positive cable, and there is a big improvement in starter performance, replace the positive battery cable. If not, keep testing.

Next in line is voltage drop across the starter solenoid. The battery cable attaches to the starter at the solenoid. It's the smaller round part of the starter. Opposite the battery cable on the solenoid you'll find another large post with a short wire that goes inside the starter motor. Check the voltage at this terminal while cranking. If the voltage here is low, replace the starter assembly. It will come with a new solenoid.

The maximum voltage drop between the battery positive and the motor side of the starter solenoid is .5 volts.

Then you need to start checking voltage drop across all connections and components on the negative side. Do this by leaving your negative meter lead on the battery negative post (connect to the battery post, not the battery cable end on the battery), and check the voltage (while cranking) of each connection as it goes to the engine. First from post to the cable end connection at the battery, then from the post to the battery cable end at the engine, then from the post to the block next to the battery cable on the engine, then the battery post to the starter housing. The maximum TOTAL voltage drop between the negative battery post and the starter housing is .5 volts.

After you've done these things I will be shocked if you don't find the problem. Even if you determine early on that the starter motor is dragging and needs to be replaced, it's good to check your voltage drops anyway. Starters that run on improper voltage don't last.

[Charlie]

Tornadsailing,

Thanks very much for your post. It was very through (sp?) And well thought out. I really like the idea of using jumper cables. Not having the experience you have the only thing I can add is that Nigel Calder's book on repairs has a very good section on testing starters for voltage drop with a multimeter.

[Tornadosailing]

Originally Posted by Charlie

Tornadsailing,

Thanks very much for your post. It was very through (sp?) And well thought out. I really like the idea of using jumper cables. Not having the experience you have the only thing I can add is that Nigel Calder's book on repairs has a very good section on testing starters for voltage drop with a multimeter.

I really need to buy that book. While a lot of things are very similar between automotive troubleshooting and marine, some are not. I'm sure I'll be caught with my pants down at some point, thinking I know something that "should be the same" but isn't.

[Tornadosailing]

After thinking about this for a minute, there's no reason you can't use jumper cables to bypass any potential voltage drops on the negative side as well. Just hook up the cable from the negative battery post to the case of the starter. If you've jumped around both the positive and negative voltage drops, and you have a good battery, it's time for a starter.

But don't use wimpy jumper cables. No one likes a guy with wimpy cables.

[Charlie]

Originally Posted by Tornadosailing

I really need to buy that book. While a lot of things are very similar between automotive troubleshooting and marine, some are not. I'm sure I'll be caught with my pants down at some point, thinking I know something that "should be the same" but isn't.

It is often referred to as "The Bible" Great book. Has really helped me out in a pinch on more then one occasion.

[NYSail]

Also a problem my engine had was that the battery is below the sea water pump. When the impeller was changed by the p/o it looked like water would fall all over the battery terminals AND cables. My neg cable looked not so bad, however when I removed it and bent it at the connection point you could hear the wires crackling. I cut it open and it was green and corroded for an inch or so up the cable. I replaced that as well as cleaning all negative and positive connections and engine starts immediately every time.

My engine was not equipped with the glow plugs.... I assume an option but I don't have. And honestly, these small compression based Yanmar engines really don't need it. Last winter in January.... 15 degrees out I started my 3HM35F for a survey on my old boat. Engine didn't hesitate to turn over. I did though rotate the engine by hand a few times with the decompression lever pulled prior to starting to get some oil flowing.....

[Wotname]

Originally Posted by noviradio

engine was always start rough(2-3)seconds in last 2 years with optima,never starts in first shot,only when it was warm.Tempereture when starting was about 10 degrees.
Today I measure the voltage on battery and starter motor during cranking,results are:minimum voltage on battery was:10.64V,minimum voltage on starter motor was:9.7V.
.......

Presumably that is 10 degrees C, not F...

The 1 volt difference between battery and starter motor volts is concerning although not a show stopper.

Tornadsailing has given you some very good advice (post #24 & 27) and the only thing I can add is:
Where did you attach the leads of the meter when measuring the starter motor voltage?

The positive lead should have been on the starter motor terminal (not the solenoid terminal) and the negative lead should be on the case of the starter motor (not on the engine or battery -ve terminal).