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Philpott
08-19-2013, 11:19 AM
10 miles out of Half Moon Bay my engine sounded different. I turned it off and crawled into the cockpit hatch to see what was wrong. "Thank goodness there is no wind" I said to my boat. My muffler had blown up. I thought diesels liked to be driven. I disconnected the clamps and put the unit into the cabin. When I was again in the quiet cockpit I said to my boat "Oh, there is no wind, it's a sail in the fog for us, honey". So we sailed at about 1.7 knots and never saw land, and the fog at the entrance to the gate obscured the towers. I could glimpse the bridge through the fog as I sailed under it. Now that was cool. Thank you, MX Mariner'

BobJ
08-19-2013, 12:08 PM
1) It's always the engine.

2) You talk nicer to your boat than I do to mine. MUCH nicer.

Philpott
08-19-2013, 07:03 PM
Turns out it was the doohicky that provides water to the engine. No, not the water pump, because that's brand new, right.? It's a vetus something, plastic. Tomorrow I'll sail it over to the marine center and all will be revealed. I think there's an impeller in their somewhere, so says my brother.

BobJ
08-19-2013, 07:21 PM
"You're killin' me Smalls!"

That's the lift can - it cools the exhaust before sending it out through the exhaust hose. The impeller is on the water intake side - it pushes the water into the engine.

Until you put the lift can back on, make sure the transom exhaust hole stays above the waterline!

KKMI does classes on diesel engines. I think OCSC does too now and then. Just a thought . . .

Philpott
08-19-2013, 08:20 PM
Can't we have a transpac seminar on diesels? At a marina!! ?? Or just an SSS seminar? I'll bring all the food. And donuts.

brianb
08-19-2013, 09:50 PM
Sounds like a good idea. What time did you get out of HMB. I took off at 0600 and there was no wind for at least two hours.

Too bad about the diesel exhaust system. There is a lot there that can go wrong. A class would be a good idea.

Wylieguy
08-19-2013, 10:24 PM
Jackie, I think Bob's idea of a diesel is a good one. It's more complicated than a 2-hour panel discussion at the OYC. In addition to the cooling system, there's the fuel system with its filters and injectors (and how to bleed them). There's also the electrical system, which for a diesel might be simpler than for an gas engine - if you can hand crack the thing to get it started. It doesn't need electricity to run; that's why the "kill switch" closes off the fuel supply instead of disconnecting the battery.

A simplistic look at the raw water cooling system: It's an open loop, with one end being the intake sea cock somewhere in the bilge under the engine. From there a hose to the raw water pump, which forces the water through the engine block and head to cool it - there's usually a thermostat in there to control the flow and keep the temperature regulated.

After the water passes through the engine, it's introduced into the exhaust gases in the water lift (the plastic flower pot you mention). The combined exhaust gases and cooling water are expelled through the exhaust fitting on the transom.

Each one of these elements can fail. There are several severe results of that failure. 1) The engine will overheat, seize up, and be destroyed. 2) Without the cooling water being introduced, the 1000 degree exhaust gases will melt the exhaust hose, filling the boat with exhaust gases and water entering from the transom fitting. 3) Since it's an open look: ocean-to-engine-to-ocean. If some fitting/hose/water lift fails, you'll sink. The sea cock on the intake will close off that end. The exhaust end doesn't have a sea cock, so if something fails after the cooling water exits the engine, things can get serious very quickly. If a hose fails, the water pump will continue to do its job, filling the bilge. If the water lift, exhaust hose, or the clamps holding the exhaust hose to the transom fitting fail, there's the possibility of water entering the hull that way, especially with a following sea.

When I sailed a boat with an inboard, I kept a wooden plug sized to jam into the exhaust fitting on the transom. In a Coastal Cup race when my water lift failed (and it was stainless steel) I used that plug to keep water out from off the Sur Coast to Catalina Island. Needless to say we didn't motor any of that distance! Sometime I'll regale you with all the ins and outs of that story.

So, while you're getting the water lift replaced, be sure to check out the entire exhaust system, including all the clamps and the hose. In an old boat, all of those things probably need to be replaced. And, don't forget to service the intake seacock and check that hose and clamps.

Pat

Philpott
08-20-2013, 08:05 AM
Thanks, Pat. Today's task: remove the cover of the brand new water pump and check the impeller. Several great step by step instructions online with photos. I will also buy extras w gaskets to have onboard. Keeping a wooden plug for that transom opening is an excellent suggestion. I'd love to hear that story sometime.

brianb
08-20-2013, 12:24 PM
Speaking of hand crank starting: There was a cool moment in the Southern ocean, aboard one of the Vendee Globe 60 footers. The skipper had run the batteries down and could not start the engine. He wrapped his main sheet, with the help of a few blocks, around the engines main belt pulley. Set the engine up for starting, then did a jibe in the roaring 40's wind and the force on the sheet spun the engine over and he was back to charging batteries with full electrics operational.

Wylieguy
08-20-2013, 01:15 PM
Yeh, and a good thing he didn't get caught up in the sheet as it flew out. Big splash!
Jackie, yes, spares are very important, as is the knowledge to make the repair should it occur while sailing/motoring. Be careful not to nick the gasket and make sure the bolts holding the cover in place are secure. If it was the "Vetus something" however, it's on the out-flow side of the system. If you're pumping water, it shouldn't be the pump.
Pat

Mewes
08-21-2013, 12:14 AM
At the end of next month Island Yacht Club's annual Women's Sailing Seminar features a session on Diesel Engines. The whole program is pretty informative, take a look.

http://www.iyc.org/wp/wss/2013-wss-class-descriptions/

Led by really accomplished sailors, too.

Lucie

Philpott
08-28-2013, 08:27 PM
I have learned how to check the water pump's impeller. That was working fine. What caused Dura Mater's engine to overheat was that the thermostat was corroded shut. Yup. And so today I spent 1.5 hours contorted in my port lazarette while I unscrewed the old thermostat. I did it by touch since it is obscured by pesky engine parts and wiring and etc. Yikes. The conclusion (by all) is that it is probably the original thermostat and it is a good thing I discovered it now. Yeah, right. I wish I'd discovered it in the bay instead of offshore in the dense fog (if I'm looking for sympathy from this crowd I know I won't get it), but that's just the way it goes sometimes.

Philpott
11-30-2013, 10:54 AM
That's the lift can - it cools the exhaust before sending it out through the exhaust hose. The impeller is on the water intake side - it pushes the water into the engine..

I bought a new one and installed it. On Wednesday, returning from Clipper Cove w my friend Jocelyn, I realized that no water was coming out of the exhaust. Turned off the motor, floated with the flood into the Berkeley marina and my slip on O dock under sail. It took 2 hours, but it was a lovely balmy night. We decided to call it an adventure, though when the smoke billowed out, she was keen to use the fire extinguisher. The flange on my (new) Vetus waterlock melted. Now I'm thinking that my engine woes might be due to a clogged/dirty/malfunctioning heat exchanger. Who knew I had a heat exchanger? The manual knew. So today that's what I'll be doing. Finding it, removing it, and looking it over. Monday I'll meander over to the Berkeley Marine Center. I'll sit outside on the bench holding it and several people will give me several different bits of advice. Sort of like this forum. O Dock Slip 212. I have strong coffee capabilities on board.

Later: Can't find anything that looks like a heat exchanger on my boat. Universal M15; should be there, yet it is not. Any thoughts?

BobJ
11-30-2013, 05:51 PM
It's sea water cooled like my Yanmar 1GM = no heat exchanger. See the link. Most of the time you'd be right though - most are fresh water cooled.
http://www.marinedieseldirect.com/universal/200157/universal-owners-manual-m-15-specifications.html

Your new impeller might have had a problem. I had one where the metal core separated from the rubber part and it was spinning but not pumping. Since you've had it out before, take a look at it. Without cooling water, the engine probably got so hot it melted the flange on the plastic lift can.

I'm really, really sorry about your engine problems. I hate engines.

Philpott
11-30-2013, 05:58 PM
Thanks, Bob. Please note that on the bottom image you sent it includes and refers to a heat exchanger. What's all that about? There is nothing like that (nothing!) on my engine. I know because I just crawled out from under my cockpit to take another look. I am so grateful when my engine runs ("oh thank you!thank you!" I say to it.) When it does not, I am grateful that I can raise my sails because YES! I have a sailboat. And I never NEVER sail near a lee shore from which I cannot sail away.

BobJ
11-30-2013, 06:10 PM
So it does - I just looked at the list at the top and saw "Sea Water Cooled" in the right-hand column.

Critter
12-02-2013, 11:54 AM
One other possibility, Jackie: I assume your engine is of comparable age to mine (1980 Volvo MD7A). My water pump was getting so worn (i.e. clearance around the impeller) that it wouldn't generate enough suction to prime itself and start pumping. A new impeller didn't help. The last couple of times I sailed, I had to disconnect a water line and fill the system from the dock hose while the engine was running. Then I could shut it down and it would pump water if I restarted the engine a few minutes later. But at the end of the day, coming in to the slip, nothing.

Over the last couple of weeks I disassembled the pump, machined the bottom of the impeller chamber flat, and machined an equal amount off the sealing face to keep the depth the same. I also installed new shaft seals. Saturday it went back on the boat and - after some worrisome dry running - it started gushing out the exhaust. Gushing, I tell you! Very satisfying.

So a new or rebuilt water pump may be what you need. If you take out the impeller and can see or feel irregular wear in the back of the chamber, I bet that's part of your problem.
Max

Philpott
12-02-2013, 01:54 PM
That word: Gush. I long to see it. Sadly, I have a brand new shiny Oberdorfer pump. I'm thinking it might be that my water strainer (very cool, very old bronze perko) had a leak so there is no pressure. Having spent 4 hours below deck on Friday removing it and checking all the hoses, I removed that also. Again. Next I'll go to Svendsen's for a modern strainer. Did I mention that I checked all the hoses? There are a LOT of hoses between the thru hull and the exhaust in the back, all in very inconvenient places. When you say you had "some worrisome dry running", how long was that? 2 minutes? 5 minutes? For how long were you worried? Because my engine runs great. I just don't want to burn it up while testing it. And I'll check that impeller again, too. Thanks, Max!

Critter
12-02-2013, 08:00 PM
When you say you had "some worrisome dry running", how long was that? 2 minutes? 5 minutes? For how long were you worried?
At least 5 minutes. After the last South Beach race, I started it outside the marina when we were ready to drop the main, and we got into the slip without the alarm going off. And I could hear the exhaust echoing in the dry muffler. Saturday, after installing the pump, I ran it longer but I could hear some gurgling and there was an occasional feeble spit out of the exhaust. So it wasn't totally dry. I think my Volvo is a big lazy hunk of cast iron, and it doesn't get hot very quickly.

Philpott
12-02-2013, 09:02 PM
That is very helpful, Max. Thank you. I'll try the hose directly into the engine first to isolate the problem. If water comes out of the exhaust I'll work backwards. I'm thinking it must be the water strainer seal. Five minutes. Wow. That's a scary long time. Terrific to hear that the issue has been resolved for Solar Wind.

brianb
12-02-2013, 11:19 PM
HI Jackie, I recently suffered some similar symptoms. Mine were a minor change in the noise / rattle coming from the engine. This led me to run at lower RPM's. Coming back from Vallejo the noise got worse, a light popping sound. I shut down and sailed home. A week later out testing an AP the noise went up a notch, louder popping. I sailed home. It all turns out to be a build up of carbon and unburned diesel in the exhaust riser/mixer/exhanger. Just past the exhaust manifold. I have taken this heavy metal object off and have cleaned the passage with a chisel, wire brush, and a piece of standing rigging. Finally I have taken it to an auto shop for an overnight soak in there cleaning bath. THere was a lump in the path the size of a ping pong ball that 1/2 clogged the exhaust stream. A diesel mechanic told that for sure this would explain the symptoms.

I wanted to offer an alternative means of getting information. On the day of the next Berkeley mid winters stand on the sea wall dressed in foulies with a cardboard sign, " Will crew for diesel advice".


Brian

Philpott
12-03-2013, 10:02 AM
I wanted to offer an alternative means of getting information. On the day of the next Berkeley mid winters stand on the sea wall dressed in foulies with a cardboard sign, " Will crew for diesel advice".

Brian

Your solution sounds great. I assume the Olson 34 is fresh water cooled. I don't think I have that option on my Universal M15. I agree that there are different ways to get what one needs. Two years ago I approached Bob Grey @ Berkeley Yacht Club about hosting our first Round the Rocks race. The barter agreement was that in return I work race committee for a season of that club's midwinters. That was a very pleasant trade, especially since there is often little wind and I'd rather sit around and eat sandwiches on a beautiful boat than float around for hours on the Olympic Circle in Dura Mater.

brianb
12-03-2013, 01:30 PM
The fact your engine is raw water cooled makes no difference. You should still have a riser/anti-siphon/heat exchanger, or what ever they call it on Dura Mater. All boats will have a device to mix the raw water coolant with the exhaust stream and them pump it out the back. According to my local tractor mechanic this is the most common failure he sees in all diesel installations. The exhaust stream slowly closes down and the engine cylinders then don't empty fully after combustion, causing a noisy popping sound. A way to test this is to remove the this heat riser and run the engine for a minute with no exhaust (muffler). It will fill your cabin with exhaust, but only for a minute. If the engine runs well then that is the problem. When, and if, you do this the noise in the boat will be very loud. Kind of like the GTO all the hot guys in high school tooled around in.

Of course you could have some other issue, but the fact your engine was making funny sounds and it ran sometimes, slowly getting worse, sounds like my symptoms and what the mechanic described to me.

BobJ
12-03-2013, 04:33 PM
When my Yanmar's exhaust system had arteriosclerosis, it got a Gucci new "chrome" exhaust elbow:

491

Philpott
12-03-2013, 05:35 PM
All boats will have a device to mix the raw water coolant with the exhaust stream and them pump it out the back. According to my local tractor mechanic this is the most common failure he sees in all diesel installations. The exhaust stream slowly closes down and the engine cylinders then don't empty fully after combustion, causing a noisy popping sound. A way to test this is to remove the this heat riser and run the engine for a minute with no exhaust (muffler). It will fill your cabin with exhaust, but only for a minute. If the engine runs well then that is the problem. When, and if, you do this the noise in the boat will be very loud. Kind of like the GTO all the hot guys in high school tooled around in.

This makes perfect sense to me. I just can't locate the heat exchanger on my own engine. I found this great article:

http://www.pbase.com/mainecruising/heat_exchanger

which describes the process you suggest. I'll go down and crawl around some more tomorrow.

BobJ
12-03-2013, 05:57 PM
Jackie, if I understand you and Brian correctly, you're focused on different ends of the cooling system.

When the water pump draws water IN to cool the engine, it is raw (sea) water. Most diesels don't shoot this sea water into the engine directly, they pump it through a heat exchanger where the hot, fresh water that has gone through the engine can transfer its heat to the cold sea water. Apparently your engine is like mine - it DOES shoot the sea water into the engine directly. That's why you can't find a heat exchanger on it. But all this is happening on the water INTAKE side.

What Brian is writing about is what happens after the hot water comes out of the engine, on the EXHAUST side. The elbow (shiny thing in my photo) sends the hot exhaust gasses to combine with the hot water exhaust in the lift can (the Vetus plastic part that melted) and then out the back of the boat.

brianb
12-03-2013, 10:30 PM
This makes perfect sense to me. I just can't locate the heat exchanger on my own engine. I found this great article:

http://www.pbase.com/mainecruising/heat_exchanger

which describes the process you suggest. I'll go down and crawl around some more tomorrow.

Hi Jackie,

I will be in Alameda tomorrow until 1 30 pm and could stop by Berkeley around 2 pm. If you want another set of eyes on the engine.

Brian

Intermission
12-04-2013, 11:53 AM
My little one lung Faryman diesel is raw water cooled, and the water jacket that was replaced a few years ago, (hot salt water on the alternator seemed bad), is already exhibiting small signs of corrosion.
The previous owner, spliced in a Prestone flush kit tee just above the intake, and after every use, the engine is fresh water flushed with the flush kit hose in a 5 gallon bucket.
I really think this continued practice has saved me some grief and expense.
A little Mrs. Stewart's bluing in the bucket indicates the system is flushed through.

Philpott
12-04-2013, 02:47 PM
oops! Just got this email! I'll drive down to the boat right now (1:45pm) in case you stop by O Dock 212. That's the entrance nearest the Berkeley yacht club.

Mewes
12-05-2013, 02:40 AM
LOL. (Laughing out LOUD!). Trust Ragtime! to want the Gucci treatment!

BobJ
12-05-2013, 09:09 AM
You should see the new chartplotter she's getting for Christmas - I may need that third battery!

brianb
12-05-2013, 10:34 AM
You will regret that ! My little garmin, min size network plotter, is a power pig. ALl the new plotters are due to the wonderful, bright, color display that needs lots of backlighting energy. When on a longer event I keep the display at min brightness. I would have preferred to shut it off but it has to be on to trigger the radar every 5 min for a safety sweep.

I spoke to product mktg at Garmin and RM in hopes of discovering they were working on a lower power model, If anything they are going the other direction. Of course if your interest is just position data occasionally a handheld unit is the best solution.

But enough about engines.

BobJ
12-05-2013, 01:06 PM
It takes fewer electrons than LORAN :)

The net draw won't be much more than my old setup since I've eliminated some separate units. I had a stand-alone AIS (w/display), powered splitter, the old VHF with its bright, incandescent screen, etc.

The decision was actually between the new chartplotter or an iPad with iNavX, which would have also shown AIS targets, etc. I'm not sure if a DSC alarm would have plotted on an iPad screen. Anyway, I think it will be a nice upgrade.

Yeah, back to engines . . .

Philpott
12-05-2013, 05:08 PM
about that old no longer used and currently ignored stand-alone AIS ...

BobJ
12-05-2013, 11:07 PM
Let's pick up that thought over in the power management thread.

Mewes
12-06-2013, 09:14 PM
Good golly, I'm heading over to Power. Or maybe a new "chart plotting" thread?

I'm having a terrific time with my iNavx and iPad.

Philpott
02-22-2014, 05:31 PM
10 miles out of Half Moon Bay my engine sounded different. I turned it off and crawled into the cockpit hatch to see what was wrong. "Thank goodness there is no wind" I said to my boat. My muffler had blown up. I thought diesels liked to be driven. I disconnected the clamps and put the unit into the cabin. When I was again in the quiet cockpit I said to my boat "Oh, there is no wind, it's a sail in the fog for us, honey". So we sailed at about 1.7 knots and never saw land, and the fog at the entrance to the gate obscured the towers. I could glimpse the bridge through the fog as I sailed under it. Now that was cool. Thank you, MX Mariner'
MUFFLER REDUX: More than 1800 people have read this thread, which tells me that more people than I have difficulties with exhaust systems on old boats. Thank you to Max Crittenden, Bob Johnston, Brian Boschma and Pat Broderick for advice. Here's what finally worked for my Universal M15. The raw water thru-hull directs water via a hose to the water filter. On Dura Mater this is a bronze Perko. I took it apart and made new gaskets with gasket paper purchased from an auto parts store. Then I sealed it with blue goopy permatex. I immersed it from top to bottom overnight and no water got in. I think it is sealed. A hose goes from the water filter to the new Oberdorfer water pump. It’s a beautiful water pump. Its impeller is intact. Yes, I bought a spare.

So far, so good. Then the engine overheated (again) and melted the top of my new Vetus muffler. Oh, hell. Someone then gave me a used muffler (a perfectly good used muffler). It was sitting around in the corner of a yard, much like the Cal 20 keel given me a few years ago by Dave Morris (thanks again, Dave). Why would the engine overheat? According to Max and Brian, cleaning out the engine’s exhaust elbow helped their engines live right. Like eating more roughage works for humans. Yuck. Brian sends me a photo of the engine part. He draws an arrow: unscrew these two bolts. Duh. Surely I could do such a simple thing myself. No way. Those bolts were on tight.

I took Dura Mater across the marina to the Berkeley marine center. Kurt the mechanic snorts: “of course I can remove two bolts”. Well, he removed the two bolts, but then the elbow broke off, having rusted all the way through. I suppose it had been there for 33 years, but still. He broke it, right? Kurt felt no remorse. “Better here than out there,” is his line. I concede the point. Kurt tried to remove the elbow from the manifold. No way that was going to happen. So he removed first the alternator. Then the manifold. Now I know what an alternator looks like. And a manifold. And an exhaust elbow. I suppose Mike Jefferson thinks this is a good thing.

After separating the manifold from the elbow, Kurt rebuilt the exhaust elbow, wrapped it with fiberglass tape and replaced it. To the manifold. And then he replaced the alternator. And the muffler. And all the hoses. Finally he scolded me for the inadequate tie downs holding all the electrical wiring up above my engine. Kurt scolds me every time he works on my engine. I hang my head but I feel no remorse.

And now! When I start my engine the water gushes! Yes, gushes! No more squirts, but gushes. Like on Solar Wind. I mean Iniscaw. Whatever an Iniscaw is.

brianb
02-22-2014, 07:15 PM
Well that sounds like a great improvement and you have also enhanced the economy ! Congrats.

Philpott
02-22-2014, 07:30 PM
I prefer to think of it as the redistribution of wealth. Having done my part, I needn't throw my body in front of those Google buses.