4JH2E Idle RPM?

[Rick D]

While driving a friends 40.5 with the 4JH2E yanmar, I noticed it idles at 1100 indicated RPM. So does a friend's Cat 42. Mine idles about 600 RPM. I do know from a prior thread that these engines have pretty low oil pressure at hot idle and I will typically set mine up to 1100 or 1200 RPM rather than letting it idle at 600. So, my question is 'is it more typical for these engines to idle nearer 600 or 1100 RPM? Rick D.

 

[Bill Bell]

1000 RPM

My 4hj2-te idles at about 1000 rpm.Bill

 

[Don Berger]

Mines idles around 700

with no sig difference in oil pressure between 700 and 1000

 

[Buck Harrison]

Ditto Don,

Mine also idles around 700. However, at commissioning, I was told by Norton's service manager that Yanmar suggests that the engine run at 1000-1100 rpm while cooling down to keep oil pressure up above 40psi.

 

[Rafael Perez]

Close to 800 RPM.

.

 

[newly anonymous]

700 <nm>

.

 

[Pete]

engine idle speed

Rick-check the link below for mfg spec.Tachometers are not accurate and with out a good tach gun use the tach as a guideline only and set the idle with in mgf range and use you ear to set it at a speed that will let it put the trans in and out of gear with out clunking or unusal noises. Make sure that it is not too slow and vibrates excessively when taken out of gear and idles as smooth as posible at idle.Most tacks are accurate within 100 rpm +/- of what they read, so you should be close to mfg specs.Good Luck

 

[Rick D]

Thanks, Pete

I think I'm low and the other guys may be fast. I notice at idle in gear, they do 2.5 knots. I do less than one. Of course, props, etc. all are a factor. I don't dislike the idle at low RPM, just concerned about oiling. Rick D.

 

[Bob F]

I was told..............

On my 376, my yanmar idles at an indicated 6-800 rpm. But I was told its not good to idle for long periods at that low RPM. Better off at 10-1200 rpm when idling for longer periods.Also, when charging batteries is there a "best" rpm to run at??

 

[Rick D]

1800 RPM for Battery Charge, Bob

That is what the west coast distributor's rep said. RD