The wife and I took Palmetto Moon out today for the first time in two weeks. Engine fired right up and I confirmed we were pumping water with the exhaust. Went to the fuel pump and topped off then headed out to anchor out overnight but only made it 1/2 way out of our narrow, shallow channel when the temp alarm went off. A glance over my shoulder confimed my fears and we were putting out smoke. I immedately shut down the engine. Fortunately the little wind there was, was right on the starboard beam. We quickly rolled out the head sail and were able to avoid going aground. We made use of our Unlimited Towing with Towboat US to get us back in the slip.
I've I checked the strainer and pulled the raw water impeller and its fine. We then checked the coolant and it was low. I had a problem last year with the heat exchanger being clogged, so we removed that and confirmed that it is clear and clean. I guess the issue might be the freshwater pump, but that would not explain the low coolant or where it went. We checked the bilge before leaving the dock and it was the normal level an normal color and we checeked agian after the icident, so it didn't appear coolant had leaked. I will have the yard look at the boat next week but would like input on suggested ways to trouble shoot this problem and any ideas on what the root cause might be. I don't have access to the e-mail account I'm subscibed to the e-mail distro on until I get home so replys here or to my account at bill eight one five at hughes dot net would be appreciated.
Oh and on the way back in the channel Towboat US DID run me agound and I misplaced my brand new Maui Jim's. So I've had better days...
Bill Boggs
s/v Palmetto Moon
1991 C36, Hull 1128
Herrington Harbor South
Chesapeake Bay
What boat model are we talking about? Where are you? What hull number? If you have a Mk I versus a Mk II our suggestions for locating your Maui Jim's would be completely different.
A "sudden" overheat can typically be ascribed to an interruption of the raw water flow, not a low coolant level. But except for one check, you have done the right things...confirmed the strainer is free of debris, that the impeller is fine, and the heat exchanger is clear. Presumably the belt is OK as well; and presumably, when you were back at your slip you re-started the engine to confirm that the problem still existed...as an exterior obstruction at the water intake could have fallen off during the trip back to the slip, thus solving your problem for you.
The low coolant may be a problem worthy of addressing, but typically that's not a "sudden" kind of problem. It could be that your coolant has been low for a long time. I suggest adding coolant to the proper level and monitoring it frequently, always replacing any low coolant, until the level stabilizes. This will alert you to a continuing coolant loss, even at a low rate of leakage. It could be that after your last coolant level maintenance (replacing the antifreeze, for example) there was an air bubble in the system, and it only now became noticeable. Nevertheless, once you add sufficient coolant, you could run the engine again to confirm that the main problem - the overheating - still exists.
Back to your main problem. Could it be that while at the gas dock your intake sucked up a plastic bag or other obstruction, something large enough that it wouldn't have made it to the strainer? One check I would make is to close the seacock, remove the hose from the thru-hull, then (carefully, as it's going to get really really wet) open the seacock to make sure water is coming into the boat. There will be NO DOUBT if it is. Open it all the way with your hand over it to deflect the (heavy) flow of water. Then close it. While the hose is off the thru-hull, I would check it's entire length to verify that it is clear.
You don't have a signature shown, so I don't know if you're talking about a Mk I or II, or the area where you sail.
Larry Brandt
S/V High Flight #2109
Pacific Northwest, PDX-based
2002 C-36 mkII SR/FK M35B
I agree with Larry. Sounds like an exterior blockage. Something similar happened to me a while ago:
Among the interesting little “tidbits” of information that I’d remembered reading about on the C34 website and Tech Notes had to do with cleaning out the raw water intake with a dinghy foot pump. On a nice mid-winter March sail with Ken Heyman, our treasurer who was here visiting, we had just left the South Beach Marina and were motoring over to see the “Lady Washington,” one of the tallships that regularly visits the Bay Area and has cannonball encounters of the close kind with fellow tallships. Since it was cold out, there seemed to be a bit more white smoke from the exhaust than usual, which I attributed to the lower air temperature. Upon checking the temperature gauge, we noted it was pegged and stopped the engine immediately. Ken and I went through a checklist of actions we could take. Sailing back to the marina was not among them, since there was no wind and the end of the ebb was setting us north towards the Bay Bridge. Thru hull strainer clear – check. Raw water entering – check, but a trickle and less than expected. Raw water pump impeller in one piece – check. Raw water pump turning – check. Spare raw water pump gasket to replace cover – check. Temperature gauge working properly – check. Hoses and thru hull clear – hmm… We got the dinghy foot pump out from the lazarette, replaced the strainer and opened the seacock. Because the arrangement of the hoses and the strainer on “Aquavite” aren’t configured to connect the pump there, we removed the hose from the raw water pump and used the dinghy pump at that end of the hose. That turned out to be actually be easier than trying to work under the head sink. There was significant resistance at first, but after setting the three way valve on the foot pump to a higher pressure setting, the pump started working. Whatever had been clogging either the thru hull or the line was flushed out. Once everything was reassembled, we started the engine and all was well.
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
Sorry, I left out some important details. The boat is a 1991 MkI, Hull 1128. I have the M35 engine. I did open the seacock while I had the strainer open and based on the water flow would assume the problem is not an external blockage. We sail on the Chesapeake and one of the first things I thought of was having sucked up one of the millions of jellyfish we have this time of year but from all our trouble shooting the problem does not appear to be in the raw water circuit.
Today we added coolant (50/50 mix) and restarted the engine to see what we got. We confirmed an apparently normal flow of raw water with the exhaust. The engine started and ran normally with no smoke or steam, so we ran it waiting for the thermostat to open which I expected around 160 degrees. There was a definite surge in the coolant around that temp, so I assumed the thermostat was opening. However, engine temps continued to climb very quickly and we'd shut down when it approached 190. Reading the service manual indicated that running the RPM up could be required to clear air from the sytem so we attempted that three times and I did see some bubbles clear but the temps never stablized in the normal range. I'm thinking I have an airlock that I wasn't able to clear or a problem with the pump. The belt is fine and the pump appears to be normal from the exterior. (No wobble or anything to indicate a failure)
We have the name of a well recommended diesel mechanic so will have him take a look next week.
Bill Boggs
s/v Palmetto Moon
1991 C36, Hull 1128
Herrington Harbor South
Chesapeake Bay
I spoke to the the Diesel Guru and he wants me to do a bit more trouble shooting before commiting him to have a look. He felt the white "smoke" we saw was steam and that indicated a problem in the raw water circuit. Since I've already confirmed the impeller was good, there is flow from the through hull and have run the engine and we were pumping water, it seems unlikely that that is the current problem. I guess it might have been a temporary external blockage that cleared when we shut the engine down, and I induced the continuing problem by my troubleshooting that introduced air in the system.
The items the mechanic wanted me to check were to bump the starter with the raw water pump disassembled to confirm the shaft was turning. I think that's something I should have done earlier, but have now established is working based on having run the engine.
The other thing was to contine my attempts to bleed the air out. He indicated it could take some effort and patience, however he gave no great tips on anything else to check. He did say that it might clear on its own and run fine the next time I start it. I appreciate the free advice I as given by a well respected engine guy and I don't want to spend money unnecssisarily, but am somewhat at a loss, since he did not want to check the boat himself until after I'd done the above. If I wait till I can get back to the boat, and I am unsuccessful we'll miss a Yacht Club anchor out weekend.
Does anyone have any advice to insure there is no air in the fresh water coolant system? The manual references bleeding air at the water heater but the coolant hoses attached to the water heater seem to be completely inaccessable on our boat.
Bill Boggs
s/v Palmetto Moon
1991 C36, Hull 1128
Herrington Harbor South
Chesapeake Bay
Try this, Burping your engine: [url]http://c34.org/bbs/index.php/topic,4518.0.html[/url]
It's for an M25, might work for you since the hot water heater loop is similar.
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
Another thing to check for is a blown head gasket or cracked head. One of the easiest ways to check is to fill the engine with coolant while it is cold, and then, with the fill cap off, start the engine and watch the coolant in the fill cap hole. If there is a cracked head or blown gasket, you will see lots of burping and bubbles, and the coolant can be blown out.
If there is a gasket leak or cracked head, the pressurized coolant will enter the combustion chamber and cause steam.
If you have to remove the engines head, be sure to remove the aluminum parts between the thermostat housing and head. If antifreeze has not been changed frequently enough, corrosion can block passages entering the head.
My engine is a M25xp, but I think the M35 is similar enough to have the same problems.
Gary Teeter
1989 C36 Annie G
Hull 966
Everett, WA
Gary Teeter
1989 C36 "AnnieG"
Std Rig #966, M25xp
Everett, WA
Thanks! Now I at least have 2 or 3 ideas to try this weekend when I get back to the boat. Hopefully we'll get it licked and be able to join the anchor out, but if not we can start on sanding and Cetoling the teak trim, so it'll be a productive trip no matter what.
Bill Boggs
s/v Palmetto Moon
1991 C36, Hull 1128
Herrington Harbor South
Chesapeake Bay