Oil in gas tank... uh oh

jheatbro

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After taking the 22' ski boat out of the ocean last night and starting to flush the salt out of engine, I got an alarm that I assumed was from oil pressure (gauge was very low). I didn't have much of any light to work with but didn't want to have salt water in the engine overnight and ended up making the ridiculous mistake of putting a quart of oil into the gas tank (have about a quarter of tank of gas in their currently). This is the an old 1989 5.7L Mercruiser inboard.

Engine started right up last night but of course the alarm went off again. Realized the mistake I made this morning and not sure what to do. The engine seemed to run fine but I don't want to burn thru the gas if it's going to cause damage. Thoughts?
 

bruceb58

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Re: Oil in gas tank... uh oh

The oil in the gas is probably going to be fine. I would fill up the tank to dilute it though.

My question is how did you mistake the gas fill on the boat for the oil fill on the engine? Was alcohol involved here?

Did you check your oil level
 

jheatbro

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Re: Oil in gas tank... uh oh

I wish I was drunk - I'd have a better excuse!

There are two compartments/tanks on either side of the inboard to pour into. This is an old family boat that I only took over a few weeks ago, so I called our "boat guy" on the phone last night while working on it since I couldn't see well and he told me the oil is the one on the left (assuming you're inside the boat working on the engine while facing the rear).

After I realized what I had done, I rubbed the inside of the compartment with a finger and it definitely smelled like gasoline. The main entrance for pouring gasoline wasn't involved so I'm still *assuming* this was just another entrance to the gas tank. I'm at work right now freaking out so I haven't had a chance to give it a thorough look - I will later today.
 

jheatbro

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Re: Oil in gas tank... uh oh

Could where I have poured it into have been neither? Is the only gas fill the one on the boat, and there is no fill on the engine itself?
 

bruceb58

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Re: Oil in gas tank... uh oh

Take a picture of where you put this.
 

HT32BSX115

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Re: Oil in gas tank... uh oh

I got an alarm that I assumed was from oil pressure (gauge was very low).


Um, was the oil level indicating "full" when you checked it before starting/running?
 

jheatbro

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Re: Oil in gas tank... uh oh

No, it wasn't. It ran great all day on the ocean, and (luckily) died when I got it back to the dock. Had troubles restarting it, brough it out of the water and waited a few minutes (since I thought I may have flooded the engine) and got it going again, but with black smoke and some black liquid coming out of the drive when running fresh water thru it, and the alarm sound. Perhaps an oil leak? It was about an hour later that I added the quart of oil, started it up (sounded great), got the alarm again, and just shut it off and thought I'd wait a day.

Regardless, I'm having a friend where it's stowed take a picture to post in an hour or so to show where my idiot self poured the oil. I haven't been back since late last night so I'm not sure what the hell I did. I was just so worried about having salt in the engine overnight that I (likely) made an even bigger mistake!
 

lakegeorge

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Re: Oil in gas tank... uh oh

The oil in the gas should not hurt it, as the other poster said just fill the tank with gas, I would put premium in it this time to add a little strength for the oil mix.
 

HT32BSX115

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Re: Oil in gas tank... uh oh

No, it wasn't.
Ok......we need to ensure that we are talking about the same thing........

The OIL PRESSURE GAGE does NOT indicate oil quantity. It indicates OIL PRESSSURE..........you could be 2 quarts low and have normal pressure.

The oil dipstick indicates OIL LEVEL (Full, LOW, or in-between)



No, it wasn't.
The oil level wasn't full or the oil pressure was low when you started out?
 

bruceb58

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Re: Oil in gas tank... uh oh

The oil in the gas should not hurt it, as the other poster said just fill the tank with gas, I would put premium in it this time to add a little strength for the oil mix.
Just use regular gas. Premium does not have extra strength in it.
 

HT32BSX115

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Re: Oil in gas tank... uh oh

The oil in the gas should not hurt it, as the other poster said just fill the tank with gas, I would put premium in it this time to add a little strength for the oil mix.
It probably wouldn't make a lot of difference putting premium in it. It would take LOT more oil to lower the octane significantly.

Also, depending on how much gas the thing holds will determine if you might get fouled plugs.

1 qt added to 20 gallons of gas will give you an 80:1 mix. Most 2 strokes require 50:1 mix and they don't get fouled plugs. (that happens when some people think it's not "rich" enough and put in a little more "just to be safe")



If your tank holds 20 or more gallons of gas you probably won't notice the difference.


If it bothers you, siphon out as much as you can, fill it up with fresh gas and put back what you took out a little at a time......

I wouldn't put it in a car or truck with a catalytic converter though or you might not make the next emission test......not a good thing in the PRK (Peoples Republik of Kalif)!



Cheers,


Rick
 

jheatbro

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Re: Oil in gas tank... uh oh

Ok, here are the images my buddy took on his phone:

http://www.pict.com/expo/2443864/7bfe9d0403

1. View of the entire engine
2. Left side zoom-in of the area where I poured the quart of oil
3. Right side which I believe is where I *should* have poured the oil!

This tank I believe is about 40 gallons or so, so the 80:1 ratio should be conservative if anything.
 

bruceb58

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Re: Oil in gas tank... uh oh

You are supposed to put the motor oil in where the cap is on the valve cover. One of your pictures shows the power steering pump. Obviously you don't put your motor oil in there.

Please don't be offended but maybe you should read an owners manual or have someone show you how to check your motor oil level and add motor oil.
 

jriegle04

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Re: Oil in gas tank... uh oh

both of those pictures are of valve covers. there should never be any gas being poured into any of those holes. that is where oil goes in. either side is fine. the gas tank is a completely separate fill hole somewhere on the exterior of the boat. it will have a gas cap on it. never put gas into any valve cover.
 

Gary H NC

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Re: Oil in gas tank... uh oh

The cap on the right side is the power steering pump.I hope you did not fill it with motor oil!
The cap on the valve cover "left side in pic" is the oil fill.
The dipstick to CHECK the oil level should be on the right side near the rear of the engine.
None of these have anything to do with putting gas in...
PLEASE have someone with engine knowledge go over this with you before it hits the water again..
 

HT32BSX115

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Re: Oil in gas tank... uh oh

This tank I believe is about 40 gallons or so, so the 80:1 ratio should be conservative if anything.
If it holds 40 gallons, you're at 160:1....... if you actually did put oil in there (with the tank full of gas) ......... It doesn't appear that you did put oil in there though.

You could not have put a qt in your power steering pump (lower right of this picture) unless it was COMPLETELY empty and even then, it would still overflow.
03.jpg




If you put oil in the one below.....That's where it goes. After you put the oil in did you pull the dipstick and check it? (boat level)

02.jpg
 

jheatbro

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Re: Oil in gas tank... uh oh

Got it - yeah of course I know the exterior fill hole on the fiberglass for the gasoline, but thought there may be another hole for it on the engine itself. Looks like I did throw the oil in the correct valve after all.

No offense taken regarding the manual or being trained with some of this stuff - it's all new to me so I probably shouldn't be so stupid as to try these things myself without making certain.

Thanks for the help guys. On a related noted, last night after I put the oil in and started the engine, I got the alarm again. Does it take a few minutes for the oil to "settle in" or take effect? The engine sounded A LOT better than it did prior to putting it in - but that alarm was still throwing me off (and hardly any oil pressure - perhaps that's due to only adding 1 quart).
 

bruceb58

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Re: Oil in gas tank... uh oh

In any case, I'm guessing I should have a few more quarts or oil thrown in that valve cover on the left (or the right!)
Don't guess and don't just throw more oil in there without checking the level first. Before you check, make sure the engine is level. put a small carpenters level on the valve cover and lower or raise the tongue of the trailer until it reads level...then check the level on the dipstick.
 

jheatbro

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Re: Oil in gas tank... uh oh

Ok, will do and I'll report back. Really appreciate the help.
 

jheatbro

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Re: Oil in gas tank... uh oh

Also, any manual or guide I should pickup to educate myself on all of this stuff, or should I just have someone go over it with me briefly? I've read the boat manual but a lot of this is omitted...
 
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