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Need help cruising home on one engine

Removed the leaking exhaust manifold. put a hose in the water intake and blocked the exit point at the elbow. Turned on the hose to fill. As the manifold water jacket filled water started entering and filling the exhaust portion of the manifold. Crack internally somewhere.
 
New replacement should be shipping today. I send the other one back. Glad I didn't hydro lock the motor. Had water coming out of the first exhaust port when I cranked it. Took out all the plugs and cranked. No water there. Only from the front exhaust port. WD40 everything. Waiting for the new manifold.
 
Went for a shake down yesterday morning. Ten miles out to some oil platforms to fish. Boat ran good heat gun at arrival was 190 degrees at the center of the left exhaust manifold Port engine 140 on the right side. Starboard engine 113 both manifolds.
On the return trip I ran with the hatch partially open so that I could shoot the manifolds while running. The boat seemed to run better. Temperatures were no hotter than 145 degrees on that same manifold. Once in the harbor at idle speed cruising to my slip (about one hour) the temp rose to 165. Once in the slip I took the engine out of gear and up the RPM to 1500 the temp dropped to 113. Blockage in the block on the port engine??? Have a trip next weekend 26 miles each way with a 2 day stay. Debating if I should go.
 
jclays said:
Went for a shake down yesterday morning. Ten miles out to some oil platforms to fish. Boat ran good heat gun at arrival was 190 degrees at the center of the left exhaust manifold Port engine 140 on the right side. Starboard engine 113 both manifolds.
On the return trip I ran with the hatch partially open so that I could shoot the manifolds while running. The boat seemed to run better. Temperatures were no hotter than 145 degrees on that same manifold. Once in the harbor at idle speed cruising to my slip (about one hour) the temp rose to 165. Once in the slip I took the engine out of gear and up the RPM to 1500 the temp dropped to 113. Blockage in the block on the port engine??? Have a trip next weekend 26 miles each way with a 2 day stay. Debating if I should go.
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sounds like you are catalina bound from newport or long beach. If it were me, I'd make the trip but run it slow and easy, take your time. Make sure you have vessel assist just in case. make sure your vhf is transmitting. Its already August. Summer blowing by. BTW, the autumn can be the nicest time of year for that island.
 
Yes it is our clubs yearly Catalina trip to Whites landing. I've got a few days to figure this out and decide if I will go.
 
When was the last time the raw water pump received a major overhaul kit.....something other than an impeller and the cover gasket???
 
makomark said:
When was the last time the raw water pump received a major overhaul kit.....something other than an impeller and the cover gasket???
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Hasnt had one. Aside from the impeller and gasket I don't see anything that would affect the flow of the pump.
 
The cams are relatively soft and will wear down over time...the worn cam reduces the volume of water the pump delivers.....
 
I'm wondering why only the left half of that engine is getting hot. Yesterday at idle 166 degrees on the left side. Right side 108. A couple of the old timers at the marina thought a blockage in the water passageways in the block and or head. They suggested running a Descaling liquid thru that engine to see if it will clean it out.
Your thoughts??
 
After re-reading this page, post #68 has a hint, i think.....port engine raw water pump delivery is right on the edge of being adequate where starboard appears to have some margin. I'd would be inclined to measure the output from each pump, at 1000 and 1500 RPM and compare them. I'd bet the port side is less. if so, I'd check out the cam in the pump for wear...and if it uses the sherwood pump, with the graphite bushing, make sure that is tight, too.....

Also, the cooling water with take the path of least resistance thru the block and manifold. based on the pictures from earlier, there appears to be two sources supplying cooling water to the exhaust, 1 from the heads, at the intake manifold, and one from the tstat housing to the elbows....I'm thinking the path from the head to the exhaust has got to be bigger (flows easier) that that from the tstat to thru the elbow, if for nothing else than the cross section of the elbows...descaling wont hurt anything but I'm not thinking its going to matter much....
 
if the water flow isnt adequate, especially at low RPM, something will get hot, and the exhaust manifold is likely the first noticeable candidate....
 
I'm going to take the pump from the starboard engine and install it at the port side engine and see if there are any changes.That's what's good about having twins. Not this weekend. Im tired with working on the boat. Canceled my trip this weekend. Good size swell running in the open ocean to my destination. Don't want to lose the port engine and limp along with one engine in a swell.
 
May not be that simple...depending on the pump used....

on ours, the inlet and outlet fittings are different lengths and types, between the two...so it may be more involved than just reversing the impellers....and, the leading edge of the cam usually wears faster than the trailing edge....
 
This past weekend I ran Maritime Express which is a de-scaling acid thru my engine for 5 hours to clear any salt, rust, scaling inside my block and heads. I made closed loop in a 5 gallon bucket and used a 670gph pond pump to circulate the solution thru my engine (exhaust system is new so i bypassed it.) At the start of the process the half of my engine that was getting warm had half the return flow as the opposite side of the engine. After 5 hours both return hoses were visually flowing at the same rate. Excited that I may have fixed my problem I couldn't wait to start my engine and check it out. My starter took a dump and is going to the rebuild shop. I will have to wait. Dang.
 
Given the 50 year history and unique configuration, you are quite possibly beyond the domain where most of us have first hand knowledge....maybe your determination has resolved the issue.....bummer on the starter deciding to delay your results.....fingers crossed!!
 
Bad news. Still hard crank no start. Pulled the plugs and had water coming out of 4 of the 8 spark plug holes. All on the same side. See post 58, 59. Engine did not run. No water in the oil. Head gasket? Im now at a loss
 
Nothing left to do but pull the head and replace the gasket. and while the head is off check it and make sure it isn't warped. While you are at it and you have things apart do the other side and get the valves done. You have had one lousy season, hopefully next year will be better.
 
Before pulling the heads is there any other way I could get water in my cylinders? Manifolds and elbows are new. All raw water. No risers, heat exchangers.
 
Super Bummer on the bad news...

Assuming the exhaust is sound, the only other way for water to get into the cylinders is thru a joint in the cast iron or the cast iron itself.

The only other option I see would be to pressure test the cooling system - not hard to will take some time blocking off the hoses and getting adapters to pressurize it. It could be possible the water jacket in the intake is the source....so, if you opt to pressurize the water jacket, a stethescope may be of benefit localizing the 'leak'....
 
makomark said:
Super Bummer on the bad news...

Assuming the exhaust is sound, the only other way for water to get into the cylinders is thru a joint in the cast iron or the cast iron itself.

The only other option I see would be to pressure test the cooling system - not hard to will take some time blocking off the hoses and getting adapters to pressurize it. It could be possible the water jacket in the intake is the source....so, if you opt to pressurize the water jacket, a stethescope may be of benefit localizing the 'leak'....
Click to expand...
I wasnt aware of any joints other than the head gasket. It wouldnt be a head gasket?
 
Need some help understanding the exhaust system on marine engines. I was talking to a local marine mechanic. He told me to check if any exhaust valves are stuck open. They would therefore suck in water into the cylinders. Pretty common... My question is how and where would the water come from? If the exhaust gases are in a chamber surrounded by a water jacket how would the water be sucked into the open exhaust valve/valves. I can understand a failure in the exhaust manifold; however mine are brand new. We were interrupted by a paying customer and never got the answer. I understand a cracked head, failed head gasket but water thru the exhaust system I need an explanation....Please and thank you.
 
I don't think I'd label that as pretty common.....

Besides the water jacket, the other key feature of the exhaust is located in the elbows, about where the open end of the exhaust hose is located, but on the 'inside'. thats where the ports are that discharge the raw water into the exhaust - giving rise to the 'wet exhaust' descriptor. the port is located 'downhill' from the lowest portion of the exhast passage to keep the exhaust dry. I would say the theory the mechanic has is that a stuck exhaust valve would allow a pressure difference that would draw water 'back over the hil l(in the elbow)' and then into the manifold and then the cylinder....

In post #87, I was looking at any joint (gasketed interface) where a path to the cylinder was possible - besides the cylinder walls, the head gasket and the intake manifold would be the extent of possibilities...
 
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