My boat is 2005 Bayliner 175, with a 3.0 Mercruiser I/O set up (Factory standard), with relatively low hours, but unknown due to no hour meter. I would estimate in the 200 hour range.
We have had the boat for 3 years and last summer, mid season after 2 weeks of daily use (July) and then a few occasional uses later in July and August (i.e. one or two short lunch trips to the lake - boat has never seen salt water, only fresh water use), the oil turned milky or chocolate milkshake colored, but with no noticeable lack or change in performance. I noticed the water intrusion on a pre-trip check. I changed the oil out, replaced the filter and ran it on the muffs...oil fouled within a few minutes. Following that, I winterized the boat, with fresh oil and filter and had been meaning to get it done for some time...well it's spring now and time to get it done.
Two other data points:
1. There was signs of water in two other places, but the mechanic indicated they were likely not worrisome...maybe a mistake. We saw light chocolate colored 'pudding' inside the oil fill cap in the top of the engine and in the tube than connects the back of the top of the block to the flash suppressor (PCV valve??). With the oil always clean as a whistle he was unable to trace the cause of this buildup.
2. During the July trip, I noticed oil suddenly appear in the bilge (I do keep it clean so I noticed it right away), but it was a relatively small amount, spread inside by lots of water from the kids draining off in the boat. I could not trace a source of the oil as all fittings, lines, hoses and the bottom of the engine were dry/clean.
Given all the posts I've read, I don't think the block is cracked (given timing of when the problem started, but maybe just wishful thinking) and was initially hoping/thinking head gasket, but I'm now generally unsure where to start the process.
I am reasonably skilled at following directions (service manual etc), but am not an experienced mechanic by any stretch.
Any help would be hugely appreciated.
Mike
We have had the boat for 3 years and last summer, mid season after 2 weeks of daily use (July) and then a few occasional uses later in July and August (i.e. one or two short lunch trips to the lake - boat has never seen salt water, only fresh water use), the oil turned milky or chocolate milkshake colored, but with no noticeable lack or change in performance. I noticed the water intrusion on a pre-trip check. I changed the oil out, replaced the filter and ran it on the muffs...oil fouled within a few minutes. Following that, I winterized the boat, with fresh oil and filter and had been meaning to get it done for some time...well it's spring now and time to get it done.
Two other data points:
1. There was signs of water in two other places, but the mechanic indicated they were likely not worrisome...maybe a mistake. We saw light chocolate colored 'pudding' inside the oil fill cap in the top of the engine and in the tube than connects the back of the top of the block to the flash suppressor (PCV valve??). With the oil always clean as a whistle he was unable to trace the cause of this buildup.
2. During the July trip, I noticed oil suddenly appear in the bilge (I do keep it clean so I noticed it right away), but it was a relatively small amount, spread inside by lots of water from the kids draining off in the boat. I could not trace a source of the oil as all fittings, lines, hoses and the bottom of the engine were dry/clean.
Given all the posts I've read, I don't think the block is cracked (given timing of when the problem started, but maybe just wishful thinking) and was initially hoping/thinking head gasket, but I'm now generally unsure where to start the process.
I am reasonably skilled at following directions (service manual etc), but am not an experienced mechanic by any stretch.
Any help would be hugely appreciated.
Mike
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