Oil 'n' gas check valve in 91' 150 Merc blk max.

[bradsell]

It seems that every once in a while when I go to start my 91' 150, it simply won't combust during ignition phase. It is asif there is simply too much oil getting into the chambers and not enough gas. There must be a check valve where the oil and gas flow through.....this must need replacing....WHERE THE HECK IS IT??????? Does anybody kow where I may get free schematics for the location of this small part??? Please let me know ASAP. bradsell@excite.com

 

[clanton]

Re: Oil 'n' gas check valve in 91' 150 Merc blk max.

Unless you are geting a LOT of smoke at start up, the check valve is fine. The check valve you are looking far is in the oil line from pump to T just before the fuel pump. One way check valve set at 2 lbs.

 

[KIWI MERCMAN]

Re: Oil 'n' gas check valve in 91' 150 Merc blk max.

bradsell <br />The best thing you could do before chasing your tale is get a manual for your engine, if you are going to do-it-yourself. <br />There is a check valve on the fuel pump where the oil line from the oil pump connects. It needs a 2psi pressure to open it. If it leaks you can get way to much oil into the fuel system. This will sometimes also allow the top oiltank on the engine to lose it's level while sitting around, not all the time but can be an indicator.<br />You dont say if the engine smokes very bad when it finally does start, also a sign.<br /><br />But again find a manual first, you will save a fortune in the long run.<br /><br />Kiwi