Print

Please login or register.

[KWKloeber]

Where can I find discussion of How to determine cause of steam in the exhaust"?  I recently observed steaming from my 1989 25XP 2 weeks ago after reaching 160F. During initial pressure test of the engine water, it took 3 minutes for P to drop from 14psi to 9psi on a radiator tester attached to water access inlet on the exh manifold. I was unable to detect water coming from any cylinder with glow plugs removed. No overheating, engine temp stays at 160F, though steam is visible above 2200 rpm after engine reaches 160F.  I plan to repeat pressure test with engine cold, and if pressure still drops and no water observed in GP holes while spinning engine, I'll isolate HX and exh manifold and pressurized them. Calder's book suggested 2 causes, head gasket leak or unburned fuel. steam looks like water vapor. This discussion sound like 3rd possibility is low flow at mixing elbow which might be determined by measuring temp of the elbow. Am I on the right track?

Coolant can also get pushed into the exhaust gas via the exhaust flange -- sometimes coolant circulating through the exhaust manifold will leak past the flange gasket into the exhaust riser and out the muffler, etc.  You might be able to smell coolant (sweet odor) in the exhaust.

A leak in the Hx can also pass water, and it will typically be from the engine coolant (12-15 psi) to the sea water side (low psi) so you will see a gradual loss of coolant in the exhaust manifold until she overheats.  Is she overheating or losing coolant over time? 

With the loss of pressure with the test, I'd suspect a leaky (1) Hx or (2) flange gasket or (3) head gasket.  How old is the Hx?  Salt or Fresh water?  Isolate the HX and pressure test it first.  If it's OEM, after 26 yrs it may be a leaker.  Occam's Razor says "start with the Hx first."

Ken

[Ron Hill]

Mick : You hit "the nail on the head" about exhaust gas temperature!!  Look at #3 below

From "Compton's Trouble Shooting Marine Diesels"   
First make sure it is steam and not smoke.  Steam (water vapor) will rise and clear quickly.  Smoke tends to stay closer to the water and take longer to be diluted by air. 
Causes : 1. Water vapor from condensing exhaust gases is normal in colder climates.
             2.  Insufficient raw water flow
             3.  Excessive exhaust gas temperatures (not sufficient raw water mixing to cool exhaust gases)

Ken : I believe that most all corporations do as Westerbeke does.  Don't think you'll get any "cut-rate" parts for a Yanmar from DEPCO.

A few thoughts

       

[KWKloeber]

Ken : I believe that most all corporations do as Westerbeke does.  Don't think you'll get any "cut-rate" parts for a Yanmar from DEPCO.

A few thoughts

Ron,

yes and no.  I just bought a $90 Yanmar pump kit for a customer for $28.   If you go OEM Yanmar, you pay thru the nose, if you go original pump manufacturer (in this case Johnson) you get it reasonably.  In other cases the you can't get the part from the original mfgr. or can't find out who it is.  I don't think Yanmar has a pump it owns rights to and forced Johnson to stop selling -- maybe -- dunno.     Certainly Universal didn't have that arrangement with Oberdorfer. 

My understand (no personal history on this) is that Beta MArine is pretty much open source on their engines --  Beta actually tells owners what Kubota block it is, so that they can get Kubota parts.     Would Westerbeke do that?   

Anyway, my point (not well articulated) was "don't waste time asking the question -- we already know what the answer will be" -- EVEN if there is an alternative available, a dealer won't tell you.


Cheers,
kk

[KWKloeber]

Ken : I believe that most all corporations do as Westerbeke does.  Don't think you'll get any "cut-rate" parts for a Yanmar from DEPCO.

A few thoughts

Ron,

yes and no. 
Cheers,
kk

Ron, case in point in email below....

Ken,

FWIW- when I ordered a new fuel pump last year, *** of *** Diesel (my Beta dealer) sent me a Kubota unit. When I googled the Kubota part I found that Joes price was close to what Kubota's was- unlike other marine engine outfits that mark up the parts considerably.

Best,
C****

Not the 600% Westerbeke markup to buy a Kubota part and spray paint it Ice Blue.

Ken

[chrisyse]

Mick, You are correct. I traced my problem to a raw water inlet clogged by sea growth.  This was the first occurance since the boat was purchased 3 seasons ago.

On the outside of the hull, there's a screen type strainer on my seacock opening. It is difficult to clean with the boat out of the water, let alone in water. My plan is to change to a strainer with a hinged cover. 

The boat has a marelon seacock and thru hull fitting, which I'm guessing have a 3/4" inside dia.   We moor in Blackrock Harbor Bridgeport, Ct. which is a high growth area.

Thanks for your comments, Any further suggestions appreciated.

[Stu Jackson]

On the outside of the hull, there's a screen type strainer on my seacock opening. It is difficult to clean with the boat out of the water, let alone in water. My plan is to change to a strainer with a hinged cover. 

 Any further suggestions appreciated.

Why External Strainers are a Bad Idea 101 (Maine Sail)  http://forums.catalina.sailboatowners.com/showthread.php?t=124964

[John Langford]

I made the switch from the Sherwood to Oberdorfer M16 (base appropriately altered) four years ago and notice no difference in performance or running temperature. Because of the cooler temperature in the Pacific Northwest I get a little steam coming out of the exhaust regardless of which pump is installed. The steam is more prevalent in the colder weather. I would not go back to the Sherwood pump for all the reasons stated and I would reinforce the point that altering the base on the M16 pump to fit on the M35BC engine is an easy job.

A final note: I did have to redo the seals on the Oberdorfer pump after three years of use. That surprised me but the repair kit from Depco was only $50 or so.

[KWKloeber]

A final note: I did have to redo the seals on the Oberdorfer pump after three years of use.

How many hours?

kk

[John Langford]

I put about 100 hours on the motor per year. So, let's call it 300 hours.

[Mick Laver]

John
Great news about your success with the Oberdorfer. I had been hoping to hear from someone who had done the conversion with a M35BC. It's also heartening to hear the modification isn't so bad. I'll have to admit the description of attacking the Ob's base with a Sawzall was a little off-puttiing. A Dremel tool yes, but a Sawzall ...? I use mine for demolishing things.

Your situation is a little different than mine with the cold water/air and all. I suspect you also got steam (or at least visible condensation) with the Sherwood, yes?

[Ron Hill]

Mick : I see that John's boat is one hull# before yours.  Can't ask for a better comparison!! 

[chrisyse]

My problem turned out to be a clogged raw water inlet. Thanks to this discussion. I suspected steam in the exhaust may mean a leaky head gasket. I'm was very happy that wasn't the problem. Now I am looking to improve the inlet fitting by making it easier to clean while in the water. So we are looking for a hinged screen. Any suggestions.

Chris

[mark_53]

If the raw water inlet is clogged, there is not an issue of unclogging while in the water. I now carry a 2' length of 14 gauge romex wire to push through the through hull after removing the strainer. Works well.

[Stu Jackson]

If the raw water inlet is clogged, there is not an issue of unclogging while in the water. I now carry a 2' length of 14 gauge romex wire to push through the through hull after removing the strainer. Works well.

My technique is to remove the raw water hose from the pump from the strainer and use the dinghy foot pump to back blow.

[KWKloeber]

Ken:   

The oberdorfer water pump is working great. It's about time to change the impeller and the new pump should make replacement easier.   

FYI, upon trying to remove the alt belt to remove the old pump, I found the bolts on the alt and alt bracket seized.  After much consultation and effort, the alternated bracket broke off the block.  So changing the water pump lead to also replacing the alt and alt bracket.  Murphy's law!

Randy,

I asked about the 908 pump because Mick Laver (this thread) had issues with "exhaust steam" when he switched from the Sherwood G-908 to the Ob M-908.  I figured in LA (lower alabama?) you would have issues in the Gulf if anyone would, but appear not to.  Mick went back to his Sherwood (I personally think the issue is much ado about very little, and the Ob being a superior pump overall is enough reason to stay with it -- but HBHC of course.)  Chime in if you have noticed any steam in the exhaust?

Get a new impeller for your go-to PRIMARY spare, and save the old impeller for your go-to emergency SECONDARY spare!

-Ken