1997 200hp, to much oil on start up?

[kevincoe]

I have had a real hard time starting my 200 hp Mercury, I have a oil holding tank under my console that self feeds the smaller tank under my motor cowling, problem seems to be this. When boat sits for a while, oil backs into my fuel line and fills gas filter. My engine wants to start but can't because it is all oil and no gas? any suggestions on how to alleviate this problem? How does the oil gradually push the gas out of the gas filter? Appreciate any suggestions?

 

[hkeiner]

Re: 1997 200hp, to much oil on start up?

Your problem is most likely due to a faulty 2-psi crankcase check valve that is either feeding too much air pressure to the remote tank or is not relieving the pressure after motor shut down in a timely manner. This part is not expensive and is easy to replace yourself. There are several threads on this forum that discuss excessive smoke at start-up, which can be due to similar causes. The below two links may be helpful to you.

http://forums.iboats.com/showthread.php?t=224359&highlight=smoke

http://forums.iboats.com/showthread.php?t=182406&highlight=smoke

Let us know if you are successful in solving your problem, and if so what you did. Good luck.

 

[kevincoe]

Re: 1997 200hp, to much oil on start up?

thanks for the reply Hkeiner. After reading your thread I get a better understanding of the oil injection system. I have noticed before that my remote oil tank is heavily pressurized. This being so, should I just replace check valve #21-878105? any suggestions? Thanks again!

 

[gss036]

Re: 1997 200hp, to much oil on start up?

Hkiener is right on in his posts, he has done a lot of research and provides a lot of good info and insights, as he has worked through problems on his own engine.
There are (3) three 2psi check valves involved. You need to figure out if the tank on the boat is holding the pressure after about 5-10 minutes, if that is the case, replace the one on the lower starboad side of the engine.
The other likely one is the one on the port side, the one w/the clear plastic lines connected to it, it could be letting the oil being fed by gravity.
The 3rd one is under the oil tank on the front of the engine, it works as a vaccum break and if defective, will dump oil into the cowling, which then will have a tendancy to run out in the motor well when the engine is tipped, or down the leg when left down.
A little troubleshooting could save a few bucks. I think the valves are under $20 each.

 

[hkeiner]

Re: 1997 200hp, to much oil on start up?

This being so, should I just replace check valve #21-878105?

Yes, that is the check valve that is most likely the culprit.

However, if replacing this check valve does not solve the problem, you might consider changing another check valve that is part of the oil injection system. It is part #22-818994 (2-PSI CHECK VALVE-This valve prevents gasoline from being forced into the oil lines.) This check valve is located between the oil pump and the fuel pump and in the UNLIKELY chance that this check valve is stuck open, it could allow oil to seep from the reserve oil tank (under the cowl), though the oil pump, and then into the fuel lines when the motor is off.

When I had problems with excessive smoke before, I went ahead and just changed both check valves right away to eliminate them as possible causes.

And many thanks to GSS036, as he helped me solve my excess smoke problem earlier.

 

[kevincoe]

Re: 1997 200hp, to much oil on start up?

Thanks for the info. gss036 and Hkeiner. I am going to order both parts and I will keep you posted. Striper season is coming to Raritan Bay and I still haven't caught my 40lber. Hopefully I can get my old 1978 Grady another season or two.

 

[kevincoe]

Re: 1997 200hp, to much oil on start up?

Alright, got the parts, went to install, and then noticed a difference in the size of the crankcase valve? the other inline valve was the same so I installed. Came back to the post to see if I missed something and sure enough I missed the little part about you having a 150 hp. Does anyone know if there is a difference between the 150 and 200hp mercury crankcase valve. I see that Mercury did replace this part with a different one but it seems much smaller in size though the threads are the same? I know i should purchase a manual but am not sure which one? any suggestions on this would be appreciated? Thanks

 

[hkeiner]

Re: 1997 200hp, to much oil on start up?

The new crankcase valve is somewhat smaller than the older original style valve. I asked the Mercury parts guy the same question when I bought this valve for my motor and observed that is was smaller than the original I was replacing. He said that the valve was redesigned a few years ago by Mercury and that the newer (smaller) design is better than the older (larger) design. He couldn't say what made it better, but he did confirm that I had the correct part.

My guess is that the same crankcase valve is used on all of the different Mercury outboard motors using the same oil injection system. You probably have the correct part but you should still confirm this by looking up the part number on Mercury Parts Express website. All you need is your motor's serial number to see the parts diagram and parts list for your particular motor.

 

[kevincoe]

Re: 1997 200hp, to much oil on start up?

Thanks for the quick response H. I will look it up and then hopefully crank her up! I will keep u posted.

 

[kevincoe]

Re: 1997 200hp, to much oil on start up?

Just wanted to say THANKS! to gss036 and hkeiner once again. Finally got to take my boat out of the garage with a nice spring day in the east. The parts I changed (thanks to you! seem to have done the job.) After a couple cranks, she started strong . I haven't noticed the oil seeping back into the fuel filter either! Its just a day but my fingers are crossed!

 

[hkeiner]

Re: 1997 200hp, to much oil on start up?

Thanks for posting an update. I think that it is very helpful to post such updates so that others, with similar problems, can determine whether a suggested fix was actually successful or not. Plus, some of us that post suggestions get a small kick out of knowing that we actually helped someone.

 

[kevincoe]

Re: 1997 200hp, to much oil on start up?

Hey hkeiner, its the least I could do, and I agree with you...its nice to help someone out! By the way H....these new valves seem to be lasting better then the old ones? Or should i keep a supply of them on my boat?

 

[hkeiner]

Re: 1997 200hp, to much oil on start up?

I doubt that this valve fails often and it is not a part that I would consider buying ahead of time to have on hand in case I were to need it again. Of course, that is just my opinion, as I replaced the valve on my motor only once (replaced it for the first time last year on a ten year old motor) and it has been working fine since.

 

[kevincoe]

Re: 1997 200hp, to much oil on start up?

Thanks Hank. Your advice has helped many!

 

[Born2Fish]

I have a 2002 150XL carbureted Engine and I am experiencing the same symptoms that kevincoe was having with his outboard, I notice that there is too much oil mixed in with the gas. I also notice that some oil is making its way back into a inline filter that I have connected after the fuel separator and before the primer bulb. Lastly I also notice that gas was also getting into the oil reservoir that’s mounted on the engine. i am ordering the 2 check valves that I located, one on the port side between the fuel and oil pumps and the other is located on the starboard side on the engine block, can anyone tell me if there is another check valve that I might be missing ? In the case of the 1997 model it seems as there is a crank case check valve located on the oil tank that’s located on the boat. Also is the check valve on the starboard side on the block the crankcase check valve

 

[Born2Fish]

Sorry it’s a 2002 Mercury 150XL carbureted

 

[GA_Boater]

Sorry it’s a 2002 Mercury 150XL carbureted

After more than 8 years in the forum. you finally make your first two posts. In ancient thread, too. Start a new thread of your own so you can get some help.

Closed.