1986 150 xr2 rough at slow speeds

[quebec#1]

I bought a glastron ssv169 with a mercury 150 xr2 i think its a 1986 ? The boat starts up great but if not used for a while the oil injection beeper sounds off for about a minute or two then goes away. At warm start ups its fine a quick beep and thats it.
The boat runs great full out or when the boat is up on a plane. When i just cruise around (not at a plane) its starts to sputer like its missing and loads up . I changed the plugs and gas filter but it didnt help. It did run well the first time out this year at cruising speed but since i installed hydro stabilizer fines on the engine it seems to be worst off at very low speeds.
Is this the nature of the beast ? Its a little smoother with the aluminum prop at very slow cruising speeds VS the sst high five prop.

 

[quebec#1]

Re: 1986 150 xr2 rough at slow speeds

I think i will take off the hydro stabilizers off the engine and see if that makes it run smoother. Also Maybe the engine is sitting too low on the transom in the water. On the trailer it looks good but in the lake the rear is deep in the water, Its a boat that was only rated for a max of 120hp.

 

[studlymandingo]

Re: 1986 150 xr2 rough at slow speeds

When you are not planed out, the hydrofoil is underwater creating LOTS of drag.​