175br 3.0 mercruiser hesitates on acceleration-gctid361945

[Guest]

Hello all, I had an issue this weekend and wanted to get the advise from a few fellow boater. I have a 2007 175BR purchase new. This was the first ride for this season so I changed the oil and gear lube and started her up at home with no problem. Put the boat in the lake and she idled fine and even motored out of the no wake zone with no issues. When I tried to throttle up she started to hesitate almost wanting to die. I then throttled back and she went back to normal. Throttled back up with the same result. So I then gunned it and she hesitated for a sec and then got up on plan. This happen throughout the day until our last stop. I was taking off from our last stop and did not have the hesitation. I also notice that I was only getting to 4000 rpms at full throttle but that could have been from the windy day and my bimini top being up. OK so that being said, what would you say the problem is. I was thinking (hoping) it could be the old gas from last season. My last ride of the year was around august 2011. So I was going to get some fresh stuff in there and see how that works. Could it be my carb needs to be cleaned? How about my spark plugs? It has been 2 seasons since changing the spark plugs and have only 40hrs combined in those two season. Thanks in advance and I look forward to reading your ideas.

Matt

[Guest]

Mine does this also, but only the very first time I throttle up on any given day. It starts easy, and idles fine, up to steady normal temperatures. I just have to coax it up very very slowly to full power - if I go too fast, it hesitatates on the verge of stalling. Once I do get through this, I'm good the rest of the day with no problem at all, even if it has cooled down fully between starts. Have had it fully tuned up, new plugs, distributor cap/rotor, good gas, clean filter, etc., still can't shake the problem. I live with it. Since it always goes away, it hasn't been a big issue to me.

[Chief_Alen]

Choke fully open ?

Maybe you need a carb rebuild the accel. pump is going.

Maybe the screen in the fitting that enters the carb is dirty.

Maybe the fuel pump is lazy, what psi is it giving you ?

Maybe the anti-siphon valve " one way valve " located on the tank pickup is sticking, or maybe there is dirt on the screen on the fuel pickup tube connected to the anti-siphon valve.

Maybe the vent is clogged with critters.

Maybe the cable needs to be tightened up a little.

Maybe you need a tuneup ? Pull the plugs and read them maybe do a compression test with them all out and the throttle fully down.

http://www.secondchancegarage.com/public/186.cfm

[Guest]

Mine does this as well, since bought new in 2008. I have done it all to make it go away. But mine only does it after cold start up and after the elec. choke is fully opened. What I do now is throttle the engine up a few times to 3000 rpms before i get up on plane. And it will kind of choke out a bit, then after that she runs great all day and night.

To me it seems that the electric choke is somewhat trying to fully disengage after warm up temp is reached and the hissing choke sounds goes away. So like I said I just bump the throttle up to 3000K a few times, then just take off.

[Guest]

I'm in the same boat (so to speak), my 2003 175BR has the same hesitation problem when accelerating up to plane for the first time, we have to edge the throttle up very slowly or it feels like its going to stall. The problem is at its worst after a cold start, even if we've been heading out of the marina a 6kn for 10 mins or more before accelerating, it seem less pronounced later in the day after the engine has had a good run.

So far, I've changed to a large external fuel filter and removed the one from the mechanical pump and I've also tested compression and replaced the plugs, HT leads abd distributor cap. The starting seems much better now and the hesitation is slightly reduced but its still a problem and I'm not sure what to try next.

[Guest]

I don't get this problem but am making this post to get the subscription emails and future posts, as it seems it could be a common problem and might happen to me one day.