Merc 150 XL OS

[RoadDawg]

I have a Merc 150 XL OffShore and was wondering how long after starting up should I see water coming from the motor??? Does this thing have some sort of thermostat in it??

 

[grandx]

Re: Merc 150 XL OS

Up to 20 seconds, takes a while to fill up the empty spaces before it comes out the tell tale. I have a pair of the same engines, never have had very strong streams, but always have a stream after about 15-20 secs. Have replaced impeller twice in 2 years, in both cases they were in good shape (didn't need it, but got new ones anyways).

 

[AndyL]

Re: Merc 150 XL OS

I have same thing with my XL since it was new. It sometimes takes 30 seconds and then it is very sporadic and weak when engine is at idle. I was told it is because the with the XL versions the water pump has a greater height to lift. Even stretching the poppet valve spring did not make much difference. It seems to just be a trait of the engine. Keep an eye on the water temp however as they do run at about 160~170 deg on idle.