Quick Yanmar Engine Test

[pwilliams]

Forum:

I was surfing the forum yesterday when I came across a great "down and dirty" test for a deisel engine. It summarized how to tell if your deisel was in generally good shape.

The test mentioned quick to start, no sheen on the water, running at WOT w/o smoke, etc.

I wanted to print the post right then, but I didn't have the time at that moment. Now I can't find the post here on the forum.

Can somebody help me find this post?

Thanks
Pat

[bljones]

Right here, third or fourth post down:

http://www.cruisersforum.com/forums/...own-50390.html

[GordMay]

Originally Posted by bljones

Right here, third or fourth post down:

http://www.cruisersforum.com/forums/...own-50390.html

Where David said:

Originally Posted by djmarchand

Redbeard:

Do these simple tests:

1. Start the engine cold. If it starts easy with just a few seconds of cranking then the compression is ok and the injectors are probably ok.

2. Check for an oil sheen on the water immediately after startup. If none, then the injectors are definitely ok.

3. Open the valve cover cap- where you add oil, and put your hand over the outlet. If you don't feel pulses of exhaust then the compression and valve guides are ok. This test is not really necessary if #1 is good.

4. Run the engine at wot in neutral for a few seconds. Does it hit rated rpm plus a hundred or two. This tells you if the governor is ok.

5. Once you determine #4 is ok run the boat at wot for ten minutes. Does it reach rated rpm? Does it overheat? Does it make a lot of black smoke? There are several reasons for not being ok but probably the most common is a plugged exhaust elbow- replace.

If all of these tests turn out ok, you are probably good for thousands of hours of uninterrupted service from this engine.

BTW the spares kit is a good price for what it covers and the injectors are worth the price of the kit, but you don't need 4 injectors. Two will do and make sure that these are well protected from rust.

David

[bruce smith]

I would think the most common reason for blowing black smoke ( un burned fuel) would be fouled bottom/ prop or too larrge a prop.

[drinky]

This may sound dumb but what is WOT. Wide open throttle???

[Badsanta]

yes on the wot

[pwilliams]

I thought I looked at that post, but I guess I missed it.

Thanks everyone.

Pat