1985 Merc XR2 150hp Fuel Issues

Hello all, I have a 1985 Merc XR2 150 that I am having some issues with and it is about to drive me crazy. Here we go! When you run the motor on muffs it sounds great and no fuel leaks and primer bulb stays hard. Now when you take it to the water it cranks great has good idle and when you gas it it jumps right out on plane within 30ft and wants to run like a scalded ape for about 200yards then it starts bogging down, let off the throttle and it picks up again for a few seconds then completely stalls till you let off the gas. Now, I can go pump my primer bulb and it is spongy and pump more fuel in and it will run great again for the same amount of time. Now to what I have done to it. I have put a new fuel pump diaphram kit in thinking not pumping fuel. Did not work. I put the good mercury fuel line and primer bulb not the atwood crap. I have a mercury filter after the bulb and an inline filter after the fuel pump. All the carbureators have brand new needles, seats, and floats and cleaned thoroughly. It has a brand new impeller and Poppet valve diaphram and gaskets put in. All new fuel lines on carbs. Now I made sure the fuel tank vent was hooked up and it is, but the fuel tank pick up I cannot get out of the tank to check the status of it. Im sure this is prolly where I will find my problem but any other opinions would be great.

Re: 1985 Merc XR2 150hp Fuel Issues

but the fuel tank pick up I cannot get out of the tank to check the status of it. Im sure this is prolly where I will find my problem

Click to expand...

Ayuh,... I think you're Right...

Hook up a remote tank,+ Try it...

Btw,... Most Pickup Tubes come out With the elbow fitting in the top of the tank...

Re: 1985 Merc XR2 150hp Fuel Issues

I got a discount on my XR4 because it had this issue. I wound up hooking up a fuel pressure gauge to track it down. In all, I found all of these faults. Fixing each one helped some.

Dirty fuel
inline fuel filter (in engine) plugging repeatedly.
fuel pump valves warped (old rubber style)
Carb floats misadjusted.
internal fuel hoses
fuel hose and primer bulb assy. (Attwood, not adequate.)
fuel bayonet connector (Attwood, again)

One thing you need to know. Resist the temptation to try to run it like this. Just before flameout, it's running lean enough to seriously burn down the powerhead.

hope it helps
John