3.0 Oil Leak

djpeters

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Let me first say this has always been a freshwater boat, nothing is rusted out. I'm chasing an oil leak, I thought I fixed it when I found the oil pressure sender loose. I had totally degreased the motor and bilge after tightening the sender. The next time out we ran it for a couple hours just cruising and there was a very slight bit of oil on the front starboard side of motor. Nothing in the bilge. Today we ran it for a couple hours but were pulling tubes so it got a good workout. Now I have a quart of oil in the bilge and the front starboard side of motor is very oily above the oil filter like its possibly the side lifter cover maybe? Anyone have any other ideas? I'm betting it's something simple. Thanks.
 

Bondo

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Now I have a quart of oil in the bilge and the front starboard side of motor is very oily above the oil filter like its possibly the side lifter cover maybe?

Ayuh,.... In that particular spot, yer choices are the oil filter, the side cover, or the valve cover,....

Could be any 1 of the 3,....
 

djpeters

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Ayuh,.... In that particular spot, yer choices are the oil filter, the side cover, or the valve cover,....

Could be any 1 of the 3,....

Thank you for the quick reply. Another question....it has a long oil filter on it now. It previously had a short. It's a tight fit between the filter and seawater pump hose and clamp. They are touching. I wonder if the filter could be getting side thrust and not sealing as well? I did the oil change myself, took the hose off when removing and installing filter then wiggled the hose and clamp back on. I know the filter was properly tightened.
 

Bondo

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I know the filter was properly tightened.

Ayuh,..... Doubtful,..... More likely for the hose to wear a hole in the filter,....

They're thin tin,.... Napa 1086 is the short Chevy oil filter,....
 

djpeters

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Just pulled the water hose off the seawater pump and visually, the filter looks good. The head of the motor is dry so it doesn't look like its the valve cover. Most of the oil is on the ledge just below the side cover above the oil filter.

Couple other things I just noticed. The clear hose between the fuel pump and carb is split at the fuel pump fitting. I'll replace that ASAP.

Also there is oil pooling on top of the carb where the flame arrestor sits. It's enough where it is slightly running down onto the head. Is this normal?

We're on vacation with the boat this week and in the morning I'm going to clean the motor up again, replace the filter with the shorty, and replace the clear fuel return line.

Not sure that if I can get a side cover gasket, if I could replace it away from home in a campground. I do have some tools along but it looks like the distributor has to come out.

Thank you for your help Bondo, much appreciated!
 

Bondo

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Also there is oil pooling on top of the carb where the flame arrestor sits. It's enough where it is slightly running down onto the head. Is this normal?

Ayuh,..... Sorta,..... The crankcase vent is directed to that area, 'n oil in the excess air purged lands there,....

Ya say ya got a quart of oil in the bilge,..?? Is the oil that low on the dipstick,.....

Oil's kinda like blood,... yer blood,.... alittle spilt looks like gallons,....
 

djpeters

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Ayuh,..... Sorta,..... The crankcase vent is directed to that area, 'n oil in the excess air purged lands there,....

Ya say ya got a quart of oil in the bilge,..?? Is the oil that low on the dipstick,.....

Oil's kinda like blood,... yer blood,.... alittle spilt looks like gallons,....

Yes. It is a quart low on the dipstick.
 

djpeters

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This morning I took the doghouse off then changed the filter to the NAPA 1086. The hose clamp for the sea water pump still rubs on it but there's more room for the bend in the hose now. I also degreased the motor and bilge so it's spotless again.

I took it for about a 30 minute cruise with the doghouse off, stopping every so often to look for leaks. Nothing so far. May have to take my kids tubing again today and see how it goes.
 

Lunkerman

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You might want to reroute the seawater water hose to go under the motor mount which is directly below the oil filter (if my memory is right )
 

djpeters

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Well, took it out again with the doghouse off and the only oil anywhere was a few drops off the oil change cap. It has a metal tube that comes off where a drain plug would be and comes up on the starboard side to about floor level. I tightened the cap down some more but don't think I could lose a quart out of that being it's not under pressure.

So I'm kind of stumped unless it does it again. There wasn't any obvious problem with the previous oil filter and now after a few rides the engine is oil free from top to bottom. I ran my hand all over the oil pan and no oil. So we will see.
 

djpeters

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Bondo....Really need your help again. Just took it out for an evening ride. Went 8 miles at 3200 rpm's. It ran perfect. 160 degrees as always and 60psi oil pressure. Then I sped up to 4,000rpms and after a minute I watched the oil pressure start to drop. I immediately slowed down, shut it down, opened the doghouse (which I just put on before this ride) and lots of oil in the bilge again. Front starboard side of motor dripping in oil. From the head up its dry and front of motor is dry, port side spotless. I had a quart of oil with me so I put that in and idled back to dock a mile away.

How can this thing dump so much oil so quickly? I've owned this boat five years and never had any issues with losing or using oil.

Thanks again.....
 

dypcdiver

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Sounds like a crankcase vent is restricted somewhere and at higher revs piston blow by is pressurising the crankcase.
 

Bondo

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From the head up its dry and front of motor is dry, port side spotless.

Ayuh,.... What's at the highest point of the oil,..??
 

djpeters

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Ayuh,.... What's at the highest point of the oil,..??

Halfway up the pushrod cover is wet. The entire fuel pump is completely soaked, bottom 1/4 of distributor is wet, block is wet to the dip stick tube then wetness tapers off toward the back from there.
 

djpeters

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Ayuh,..... Doubtful,..... More likely for the hose to wear a hole in the filter,....

They're thin tin,.... Napa 1086 is the short Chevy oil filter,....

Guess what? This is my problem exactly. Cracked oil filter from the hose clamp rubbing on it. More than likely the one I took off two days age was cracked as well and I didn't notice.

This makes sense since two weeks ago I did an oil change and put a new seawater pump belt on. The belt may be a touch shorter than the one I took off so maybe there's a little less room. It's stupid that they don't have some clearance designed in.

So now I have to get another filter and I'll put the old belt back on and see if that helps.
 

djpeters

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Update. I think the seawater pump has been on 180 degrees wrong for who knows how long. It I turn it 180 there's no hose clearance issues. This puts the suction side on top and the out flow on bottom. Can anyone confirm this?
 

djpeters

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Boat is running perfect again and not losing oil. I ended up getting a Mercury Quicksilver oil filter which is considerably shorter than the Napa 1086 and allows the seawater pump to be installed either direction. I'm not sure which way is correct but the hose hook ups are less jacked up the way it was (less clearance). So lesson learned, I should have put the exact oil filter on that I took off two weeks ago when I changed oil. It had the Quicksilver filter on it from the last oil change at the shop. Can't trust a parts counter that says "This will work".
 
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