Lost Power

cabwizard · **Posted:** Sat Jun 27, 2015 11:22 am

Only used my boat twice this season. After getting it back from storage and being summerized, I noticed it use a lot of gas the fisrt time out, I didn't have my GPS speedo connected so did'nt really notice the speed, but it felt slow. 2nd time out took GPS speedo with me. Shock, 3000rpm 15mph 4000rpm 25mph. It starts up 1st time with ease. No exhaust smoke at all. No overheating. No loss of oil It just feels that the revs from the engine are not getting to the prop. Theres no prop damage. I am guessing at putting premium fuel in next fill. The gas tank was full before being stored for winter and stabilised.
270 hrs on the boat. H200 4.3 GXi Volvo. Standard prop. I used to get up on plane at 2800rpm then back off to 2500rpm and be doing about 20- 23mph staying on plane. at 2500 rpm it is plowing. Any clues?

Thanks Ray

Rick2752 · **Posted:** Sat Jun 27, 2015 12:55 pm

pull your ladder in :lol:

Couldnt resist.....sorry.. You could have bad,old gas. Easist place to start i guess. Trim tabs?

GottWhat · **Posted:** Sun Jun 28, 2015 12:09 am

What is the max RPM at WOT that it was able to rev to?

LouC · **Posted:** Sun Jun 28, 2015 7:10 am

How about the fuel filter?
Sometimes the anti siphon valve on the gas tank gets corroded and restricts fuel flow.
Tune up?
Prop hub slipping?
When you say summarized what specifically was done?
I always change the fuel filter, check the dwell and timing and inspect the spark plugs to see if they got fouled from the fogging oil. If so I replace them.
On an EFI engine some of this is not needed but the fuel filter should be changed (and, the gas from the old one dumped out and let it sit in a big glass jar). You're looking for water on the bottom or other crud.

cabwizard · **Posted:** Sun Jun 28, 2015 5:01 pm

Hi, Well it was winterized and fuel filter changed and oil changed before being stored also fuel was stabilized.
It does top out WOT at 4800 rpm. It starts up 1st time everytime.
As to summerizing this season I am guessing the marina started it up, let the foggin oil burn off, check the levels and thats about it. I didn't get it tuned this summer as it was fine last summer, but I'll changed the fuel filter and refill with premium gas to improve the the octane of whats left, it is showing under 1/4 tank, but maybe start it up and let it run to burn as much off as possible. It's on my driveway, so I can let it run out then refill at my local gas station. I do have a spare prop, so I'll swop it over , but I think the prop is ok. I can't feel any play with my hand, there is no damage on the prop, just the paint worn of the edges with friction of the water. I'll let you know what happens once this friggin rain stops.
Thanks guys.

Thalasso · **Joined:** Tue Jan 18, 2011 8:45 pm **Posts:** 333

Runs ok other then no speed?
First thing i would do is mark the prop hub and see if it's slipping. That will give you rpm's but no speed

DaleG · **Posted:** Sun Jul 05, 2015 6:53 am

Agree with above post -- mark the nut and the prop so you can tell if there is any relative movement -- movement there would indicate a prop hub issue.
thx --- Dale

www.iFourWinns.com

Lost Power

Who is online