Making Steam

[EdHouston]

My W40 was running a little hot yesterday and I had some steam exiting the exhaust has anyone experienced this? And any ideas what may be wrong?

[slokat]

I've been having a little bit of a similar problem, and so far my research says it's most likely a symptom of not enough raw water flow.  My next project is to trace the whole route of the raw water line from intake to exhaust and look for obstructions, etc. 

[RayNWanda]

First check the water flow out the exhaust. Does it appear to be the normal amount? Check the inline seawater strainer- it's down near the vee drive. While it's open, point the water hose from the seacock into the bilge and crack the seacock. You should get LOTS of flow. If not, the scoop strainer may be obstructed. If you get good flow, I would try a water pump impellor. You could also have a plugged cooler.

[EdHouston]

This engine will be the death of me!

I feel much better now was thinking head gasket etc.

All raw water lines valves and connections will be checked and free flow will be restored.

Only question I have is what is normal flow? I have a fair stream of cooling water from the exhaust but hey "a fare stream is a relative term! When I was twenty years old it could be a gusher with loads of pressure (stand back or you may get splashed) now I am Fifty Odd can only express it as a fair stream!!!!!!!!!!! But hey it feels good!!!!"

Without getting a urologist involved in this discussion define normal flow???

Ed

[zaya]

Hi Ed,

if you still have steam after one hour running time, I will think you have water in your engine:

1. head gasket: is your coolant level going down ?
2. You may have salt water leaking in the engine through the raw water pump.
Check your oil, do you have sludge on the oil cap ?

also, very hard to judge if the exhaust water flow is normal...

philippe
Zaya

[kevin barber]

A little steam is usually not a big deal. 

You probably have a restriction in your raw water line somewhere.  There are several places for salt and growth to build up in the raw water system.    The steam is probably being created when the lower flow of water is being mixed in the HOT exhaust elbow.  Just like throwing cold water in a hot frying pan, you will get some steam. 

Check the following for blockage.

1. Strainer . Thru hull
2. V-drive water connections
3. Impeller
4. Heat exchanger for blockage-  remove exchanger and flush.
5. Exhaust elbow where raw water gets mixed with exhaust.  (Frequently builds up salt, remove the hose and clean out hose barb)

Also-  What does your temp gauge read when it steams? 

I battled a steamy engine for years, and finally fixed the problem by installing a higher flow raw water pump.  I have the Universal, which were notorious for steaming. 

[EdHouston]

OMG

Pulled the strainer and yes it had a bunch of crud in it, I removed the heat exchanger and flushed it let CLR do a number on it and removed all the crud (bits of old zincs) etc and it now looks clean as a whistle. I have so far re-installed the exchanger and strainer my next plan is to replace the raw water pump impeller, I am planning on removing the hose from the exhaust elbow and or the raw water pump and flushing the system with a garden hose before firing her up again.

[RayNWanda]

Don't forget to check the scoop strainer on the outside of the hull. Pull a hose off the inline strainer, point it in the bilge and crack the engine cooling water seacock open. You should get a stream of water as big as the opening in the hose. It should have a little pressure. If you don't get a solid stream, you may have critters or debris restricting the scoop strainer.

[eveningebb]

As long as you're checking the raw water system, you should check the oil cooler.  And, if you have a Velvet Drive Transmission, there's probably a transmission oil cooler plumbed into the raw water system as well.

[RayNWanda]

If you are going to flush the system with a garden hose, make SURE you disconnect the hose at the exhaust elbow. Otherwise you will flood the exhaust system with water and with no exhaust gas to push it out, flood the engine through the exhaust ports.

[EdHouston]

What a Saga

OK water pump off and replaced the impeller and flat ground the cover plate (it had been scored fairly deep the Guy at Lakewood Yacht repair said better flat it off or buy a new one they did not have any in stock so flat off I did) The impeller had ten of the twelve lobes broken so was in need of replacement.

I back flushed the system from the heat exchanger outlet to the exhaust elbow back to the intake strainer, This was a good thing because the pump would not self prime, I did try to start her after replacing the pump but she made no water after about 45 seconds so that is when I did the back flush and so primed the system.

So alls well that ends well she now has good flow and I will see what happens Saturday we have a bay race so will keep close eye on everything.

Thanks for all the great help and encouragement from all.

Ed S/V Moonlight Mile.

[captsandy]

Just one more quick input. Were any of the broken vanes missing from your impeller. If so They are someware in the cooling system and could impede the flow if you don't find them. Sounds like you have everything covered and some good advice.
     Sandy
 

[EdHouston]

No vanes missing but sure they were not performing as designed Will take photos and post later.

[JusRockin]

I replaced the original small raw water intake filter with a larger see through filter, at times kelp gets in restricting H2O flow, then I will see stream. This is a indicator to check your filters.