engine surges when first started

[thurps]

My 1985 Johnson 40 starts and idles perfectly but when I give it throttle, it surges up and down for three to five minutes. After that it will run fine for the rest of the day no matter how many times I start it, or how long I rest it in between starting. The next day it will do the same thing. Are the reeds in the fuel pump getting hard? Any other suggestions appreciated. Nothing I hate worse than buying another part only to find out it does the same thing.

Thanks, Kelley.

 

[54fleetwin]

Re: engine surges when first started

does it still surge if given a little choke?

 

[thurps]

Re: engine surges when first started

It does run smooth for maybe half a minute if I pump it up again. I have replaced the bulb and all the fuel connectors with no change. I'm fairly shure it's the fuel pump but I would like to be certain before investing in one.

Thanks, Kelley.