Good evening everyone! I bought my first boat, a 1987 C34, about 6 months ago and I've put her through the wringer with an ICW passage south, Bahamas cruising, and then back to the Chesapeake. I'm embarrassed of all the stupid mistakes I made along the way, but the journey gave me a great chance to get really intimate with all of the boat's systems. I can't put into words how incredible of a resource this forum has been in every respect. Seriously, thank you!
Currently, my most pressing issue is that the M-25XP w/ 3" HX seems to be running hot and there is constant white smoke out the exhaust. I've had two mechanics take cursory looks, and both said that the engine was running fine and there was no immediate concern, although neither could pinpoint the root cause. I'm hoping you all might be able to give me some advice to help me troubleshoot the problem and work toward a solution.
PROBLEMS:
1) Constant white smoke from exhaust, regardless of RPM or engine temp. I hate to say that I slightly overfilled the oil about a half a centimeter over the fill line on the dipstick and it was two days later that I first noticed the white exhaust smoke. Upon further inspection I discovered that oil had made its way to the bilge, presumably through a pressure release valve on the engine.
2) Cruising around 2700 RPMs, the engine will get up to 165 degrees and hold steady for a couple hours. The temp will then slowly rise before it levels off around 195/200 degrees. If I back down the RPMs or put it in neutral, the temp will go back down. Maybe this is normal and expected once the hot water heater has absorbed all the heat it can, I'm not sure?
WHAT I'VE DONE SO FAR:
1) Raw water seacock clear.
2) Raw water sea strainer clear.
3) There was a hard 90 degree turn in the hose from the sea strainer to the raw water pump and it looked like the hose was slightly collapsed. Based on a post from Ron, I installed a 90 degree elbow to prevent the hose from collapsing...that seemed to slightly improve water flow out the exhaust but did not impact the engine temp or white smoke.
4) Replaced raw water impeller, it was showing signs of cracks (I've got a Johnson water pump)...no impact.
5) Removed HX, cleared out a couple pieces of what seemed to be old impeller bits, and gave it a muriatic acid bath...no impact.
6) Blew out or replaced 5/8" raw water hoses...no impact.
7) Installed new vented loop on raw water line...no impact.
8 ) Cut out the rigid hose from the exhaust riser to water muffler and replaced it with a hump hose...no impact (the original hose didn't have any blockages in it).
9) Flushed the exhaust hose out with a water hose from the water muffler outlet to verify that it had good water flow and there wasn't a wasp nest or something in the exhaust hose. Water flow was good...no impact.
10) Verified that I'm not losing coolant...the level is holding steady.
11) Verified that I'm not losing oil rapidly...I have to add a couple ounces every 50 hours or so, but I suspect that's normal.
12) The HX and coolant hoses are hot to the touch; the hot water tank gets the water scalding hot and will spit some out of the pressure release valve into the bilge.
13) Replaced the fuel injectors based on a mechanic's advice...no impact.
Apologies for the long-winded post, I'm just trying to be as concise as possible and not miss any details. Anything that can help point me in the right direction would be greatly appreciated.
Thanks again!
Derek
Currently, my most pressing issue is that the M-25XP w/ 3" HX seems to be running hot and there is constant white smoke out the exhaust. I've had two mechanics take cursory looks, and both said that the engine was running fine and there was no immediate concern, although neither could pinpoint the root cause. I'm hoping you all might be able to give me some advice to help me troubleshoot the problem and work toward a solution.
PROBLEMS:
1) Constant white smoke from exhaust, regardless of RPM or engine temp. I hate to say that I slightly overfilled the oil about a half a centimeter over the fill line on the dipstick and it was two days later that I first noticed the white exhaust smoke. Upon further inspection I discovered that oil had made its way to the bilge, presumably through a pressure release valve on the engine.
2) Cruising around 2700 RPMs, the engine will get up to 165 degrees and hold steady for a couple hours. The temp will then slowly rise before it levels off around 195/200 degrees. If I back down the RPMs or put it in neutral, the temp will go back down. Maybe this is normal and expected once the hot water heater has absorbed all the heat it can, I'm not sure?
WHAT I'VE DONE SO FAR:
1) Raw water seacock clear.
2) Raw water sea strainer clear.
3) There was a hard 90 degree turn in the hose from the sea strainer to the raw water pump and it looked like the hose was slightly collapsed. Based on a post from Ron, I installed a 90 degree elbow to prevent the hose from collapsing...that seemed to slightly improve water flow out the exhaust but did not impact the engine temp or white smoke.
4) Replaced raw water impeller, it was showing signs of cracks (I've got a Johnson water pump)...no impact.
5) Removed HX, cleared out a couple pieces of what seemed to be old impeller bits, and gave it a muriatic acid bath...no impact.
6) Blew out or replaced 5/8" raw water hoses...no impact.
7) Installed new vented loop on raw water line...no impact.
8 ) Cut out the rigid hose from the exhaust riser to water muffler and replaced it with a hump hose...no impact (the original hose didn't have any blockages in it).
9) Flushed the exhaust hose out with a water hose from the water muffler outlet to verify that it had good water flow and there wasn't a wasp nest or something in the exhaust hose. Water flow was good...no impact.
10) Verified that I'm not losing coolant...the level is holding steady.
11) Verified that I'm not losing oil rapidly...I have to add a couple ounces every 50 hours or so, but I suspect that's normal.
12) The HX and coolant hoses are hot to the touch; the hot water tank gets the water scalding hot and will spit some out of the pressure release valve into the bilge.
13) Replaced the fuel injectors based on a mechanic's advice...no impact.
Apologies for the long-winded post, I'm just trying to be as concise as possible and not miss any details. Anything that can help point me in the right direction would be greatly appreciated.
Thanks again!
Derek