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Found Engine Oil in Bilge

910 Views 11 Replies 7 Participants Last post by  23concept
Just bought this motor in January its a 454mag 420hp. Its been running great then I noticed a lite ticking noise coming from the engine only hearing at slow speeds or idling. Then further inspection found a good amount of oil below the motor :mad: I checked the dipstick lost a quart or so. The engine still runs good, I topped off the oil and took it out Sunday didnt notice a big difference in performance, but it did seem like I used more gas then normal.

Any ideas guys?
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Look like it's coming out the "breathers"? Dipstick tube loose? front/rear seals?
the first thing is to isolate the source of the leak.

It might just be a leaky seal or something innocent like that.
Its not coming out the breathers or dipstick Im not that lucky

Rear seal is a possiblity it looks like the oil was squirting out with some pressure maybe from the transom area
Check the oil pressure sensor and the oil alarm sensor, also check any of the fittings and the oil filter adapter. Near the adapter is a 1/4 npt plug that could be loose.

Another possibilty is the pan gasket if a cheap cork one was used.

Did you figure out what the ticking is? One qt low should not cause the valvetrain to tick. If it is still ticking find out from the builder if the rockers need to be adjusted.

Good Luck!
I think ur on to something Twin, everything that I can see looks dry? Must be coming from underneath I was thinkin pan gasket too. The noise is hard to discribe , Im sending it over to Craig at Offshore to see what he has to say.
Well I got a little relief the noise I was hearing is just a exhaust manifold gasket thats a pretty easy fix.

The oil Im not so lucky still hard to tell exactly but looks like a bad rear seal :angry1: . The way its squirting out that makes sense


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I would check the oil cooler on your Lib, If it's like mine its right on the back of the motor. Mine leaked there after I had my motor out. Also sometimes the rear of the intake manifold can leak too.
what about the filter mount being loose. or adapter if you have a remote. the ticking could be caused by a rocker backing off just a thought :)
The ticking noise turned out to be a leak in a exhaust manifold gasket. The leak is still a question, took it over to my guy for a quick look couldnt find the source. Needs further deeper inspection. I got a warranty so I guess I have to ship it back to the engine bulider. The sucky part is thats 3 hour haul at $4 a gallon that sucks. :angry1:
I had a very similar type of oil leak that drove me nuts trying to find. It turned out being the seal between the engine block and the oil filter adapter. It was a real pain to find and fix in the boat, but I tore it apart and replaced the seal and no more leak.
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