yanmar 6GLYA-STP

[stepheniser]

Yoday I look at a2006 MS 40 with a Yanmar 6GLYA-STP. Total hours were 1518 and service june 2012 at 1516 hours. In the past 6 months engine was ran only 2 hours. Upon starting, the engine smoke likely and produce a light oil sheen on the water, we ran the engine for approx i5 minutes,engine temp reach approx 125. In The broker said that it was do to lack of use and if the engine is ran for say a 1/2 hour under load it will clear up, or is their some other serious problem. Please I need feedback

 

[Moonstruck]

I had one of those engines for a few hundred hours with no problems. When cold on starting it could produce some white smoke which was water vapor. I am only guessing here, but oil could have seeped into the cylinders by the valve stem seals. Sitting so long it could build up.

I have never let one idle long enough to get to operating temperature. I'm not sure that it would. It should get to operating quickly under load.

A good engine survey by a competent mechanic is called for. My experience with that engine has been good.

 

[JD]

Yoday I look at a2006 MS 40 with a Yanmar 6GLYA-STP. Total hours were 1518 and service june 2012 at 1516 hours. In the past 6 months engine was ran only 2 hours. Upon starting, the engine smoke likely and produce a light oil sheen on the water, we ran the engine for approx i5 minutes,engine temp reach approx 125. In The broker said that it was do to lack of use and if the engine is ran for say a 1/2 hour under load it will clear up, or is their some other serious problem. Please I need feedback

I think there is something wrong with the ID letters on this engine. I have been to three Yanmar sites including Boat Diesel and I can't find any such engine. The only G series Yanmars are the 1, 2 & 3 cyl GM Raw and Fresh water engines. The engine is most probably a 6LYA-STP 370 HP.

That said I agree with Don. The engine never got warm and won't get there ideling at the dock. True the water temp might get up but the internal temps will not. Tie off a good spring line and secure all of the dock lines, start her up and put her into gear. Load he up a bit and then let her run for 10 minutes.

My guess is she is just fine.

 

[DavidM]

This is what I did a few months ago as a self performed survey on a Yanmar 6LY-STP 370 hp engine:

1. Take an overall look to get a feel for how well the engine was maintained. Look for fluid leaks. Pull the zinc on the air cooler (big brass bolt on the aft port side outboard of air filter) as that is one of the first to go and see if the zincs have been maintained. Check fluid levels and the looks of the oil.

2. Start the engine from cold. It should start within 2 seconds or so. Watch for smoke which should settle down in a few minutes. Note- my engine produces white/grey smoke on startup and continues to produce some when warm. It is the nature of the beast to smoke a little.

3. Phototach the engine and get a mental calibration on the helm instruments.

4. Mentally calibrate the helm temp gauge to an IR shot of the water pump/thermostat housing.

5. In neutral, rev the engine to wot. Should hit 3,500+.

6. In gear and at cruising rpm of 2,800 or so check for blow by. Put your hand at the end of the blowby hose that is open right on top of the air cleaner. You should feel very little flow. This is a solid test for compression issues.

7. Run the engine up to wot in gear for a few minutes. Should hit 3,300 at an absolute minimum, preferably 3,400 or so. Any less than that indicates a serious problem.

8. Watch the temp rise at wot and make sure that the temp is 200 or less.

9. Back at the dock look for suspicious fluid leaks.

I believe that this procedure gave me more information than you would obtain from a general boat survey and maybe as good as a full engine survey. The steps are generally applicable to all engines but adjustments need to be made for the rated rpm, blowby hose, etc.

David

 

[JD]

This is what I did a few months ago as a self performed survey on a Yanmar 6LY-STP 370 hp engine:

1. Take an overall look to get a feel for how well the engine was maintained. Look for fluid leaks. Pull the zinc on the air cooler (big brass bolt on the aft port side outboard of air filter) as that is one of the first to go and see if the zincs have been maintained. Check fluid levels and the looks of the oil.

David

David,

That big Zinc is not the one that goes the quickest on my 6LYA-STP. The one on the trans cooler and the oil cooler then one of the ones on the water exchanger. Of the six these three are always the worst at the six month interval. I change all six with fresh, they are cheap enough.

 

[Symphony]

Hey David and others on this Yanmar thread:
The 6lya stp is a “light duty” engine - after 2500 hours of variable duty - is it reasonable to expect another 2500 before major rebuild?
This engine has had various runs of a week continuous at trawler speed as well as periids of high revs.

I have not been to the boat to start up yet

 

[DavidM]

In one case, meiculously maintained, that engine went 20,000 hours.

YMMV.

David

 

[Fletcher500]

That little red circular guy with sunglasses on in post 1 has been dancing away for almost 6 years. Impressive.