89 150 XP, low end power

[brusk]

I've got a 89 Ranger 373V bass boat with a 150 XP. Other than still trying to figure out the quirks of getting it to start up right away when cold seems to hum pretty good topping out at just under 60 with trim full up at 4500 RPM's. I'm a little concerned about the power displayed when I'm trying to get out of the hole. It seems to take longer that I would think to get on plane. I've replaced the plugs, wires and coilpacks (2 weren't sparking very well so I replaced all with new OEM parts) ran seafoam in the tank. Running 89 octane gas (not sure what's recommended). Compression checked out good at the dealer when I bought it. Is this normal for a boat like this or is there anything else I can check like the timing maybe off a degree or something.

 

[bkwapisz]

Re: 89 150 XP, low end power

I had a similar problem and fixed it like this:

1. Voltage regulator was bad, not sure if this has any bearing on your problem, but mine was bad. Figured maybe the spark was lackluster just coming from the battery.

2. Replaced the VRO pump (which had been converted to just mix) and now everything runs better. Prob could have just rebuilt it but I put in a mix-only pump.

3. When you're getting out of the hole-- is the motor trimmed up or down? I have to trim my 100HP motor down or it takes forever to get up, especially if I have a passenger sitting in the aft seat.


As an aside: After I replaced the fuel pump and regulator it stays running when cold much better and idles without sneezing and stalling. I also replaced the cam follower at this time so my timing was probably off to boot. Not sure which one of these was the true problems but the problem is gone now and that's all that really matters to me. I recently installed a tach too and noted that the idle is actually low so I need to boost that up a bit too.

Just some things to check. I'm sure the REAL gurus will chime in soon.

 

[emdsapmgr]

Re: 89 150 XP, low end power

If your engine is tuned well and running perfectly, and the tach is accurate-you've probably got the wrong prop on the engine. You should turn that engine between 5500 and 5700 rpm at full throttle and full trim. You are lugging the engine top ending it at only 4500. No wonder it is a dog out of the hole. You may need to go down as much as 2 prop sizes and you will see a much improved hole shot.

 

[brusk]

Re: 89 150 XP, low end power

wow 5500 didn't know they were supposed to rev up that high. What should a top speed supposed to be then? that would run up to 70+ i would think. Yeah I was thinking about rebuilding the VRO as I had an issues where it would work, I got mad and flew home the bouncing seemed to free it up and started with no problems once I got home. As for take off I can only get on place with trim 1/4 down to full down any more than that and it just pushes and won't do it.

Where is a good place to get a rebuild kit for the VRO (VRO2 tagged on this one)?

how do I go about checking the voltage regulator?

 

[d.boat]

Re: 89 150 XP, low end power

I can't see where you have symptoms of a bad regulator, maybe I'm missing it.

As for the fuel pump - do you think that's what's causing the low RPM's? Did it ever run higher for you or the previous owner? Does manually pumping the bulb cause it to go faster at wide open?

From what you've written, unless the fuel pump appears to be failing, if it were me, I'd be looking at re-propping to get the rpms up where they should be.