gas in oil

[cimy3]

Hello. I have 1989 Mercruiser 5.0L. Yesterday, I had a surging problem at the lake. Today, I searched on this site and came up with the following assessment....Fuel pump has a ruptured diaphram due to a gas smell from the oil. Also, I cannot see through the clear tube running to the carb, so I am assuming gas is present there as well. Before running it, I will change the oil & oil filter.

From my search, it sounds like I should change the fuel pump and all filters in the fuel delivery.

Is there anything else I should be do or be looking for?

Thanks for the help.

Ray

 

[Fishermark]

Re: gas in oil

Sounds like you have a handle on it - just make sure you replace the pump with a marine pump and you're good to go! (And change the oil and filter like you mentioned of course).

 

[180shabah]

Re: gas in oil

Hello. I have 1989 Mercruiser 5.0L. Yesterday, I had a surging problem at the lake. Today, I searched on this site and came up with the following assessment....Fuel pump has a ruptured diaphram due to a gas smell from the oil. Also, I cannot see through the clear tube running to the carb, so I am assuming gas is present there as well. Before running it, I will change the oil & oil filter.



Ray

You might want to verify defect before replacing parts.

 

[cimy3]

Re: gas in oil

Thank you for the fast replies.

 

[cimy3]

Re: gas in oil

I have not had a chance to asess the problem yet, but I was thinking (good or bad..not sure)about the last few times on the boat and it seemed to being running on the rich side...would it be that excess fuel dripped down through the carb.?

Without testing, any thoughts?

Ray

 

[HT32BSX115]

Re: gas in oil

If you had a fuel pump diaphragm failure. The tube did it's job. It dumps an inordinate amount of fuel into the carb. It doesn't prevent fuel from going the other way usually though and you'll absolutely have fuel going into the crankcase.

You can get a fuel pump at Autozone, Napa and most autoparts stores. That fuel pump is pretty much standard. They can look it up in their catalogs.

Manufactured by Master or Airtex

http://www.a-1injectors.com/fuel-pumps/buynow/60932.htm ...this is the one for a 7.4L carb'ed Merc v-8 This may also be the one that fits the 5.0/5.7's too.

Airtex is the OEM manufacturer for Mercruiser and is what Autozone sells.

BE ABSOLUTELY SURE they are looking at the marine model....they'll have pictures and descriptions in their catalogs that indicate the marine models..

I didn't believe them at first so I called AIRTEX and asked them.
http://www.airtexproducts.com/oem.htm


Cheers,


Rick

 

[cimy3]

Re: gas in oil

HT32BSX115....thanks for the reply. I order the pump, filter and gaskets from dougrussell.com. Again, thanks for the information.

Happy Boating,
Ray

 

[Bondo]

Re: gas in oil

Also, I cannot see through the clear tube running to the carb, so I am assuming gas is present there as well.

Why not Pull it Off,+ Look...............

You're just Throwing Parts at a Problem, Without knowing Why........

Thes same syptoms Can be caused by a Junk Carb as well as a Bad fuel pump...........