Loss of Power/speed

Andy b · 07-17-2013, 09:47 PM

I would agree with Mikey best I've had out of my 180/4.3L is 49/50mph.
and that was one up with half a tank of fuel
average WOT speed for me I would say was around the 46mph range
All boat speedo's are male and prone to exaggeration!

trust in GPS

kemhardt · 07-17-2013, 10:09 PM

well pulled the prop and doesn't look like a spun prop to me but then again I don't know what one looks like just what i have read. No shiney rubbing marks and no torn up rubber.

So now I am left scratching my head what it might be. I know to always start with the obvious and easy stuff but not sure where to go besides fuel or maybe lost a cylinder?

The 54 was by the boat speedo.

***mikeyt*** · 07-17-2013, 10:16 PM

Might be time to do a compression check on all of the cylinders as well as a timing check. If you read my post here, there is another fairly simple method to check for a spun hub.

kemhardt · 07-18-2013, 12:31 AM

Ok...I have ruled out a spun prop.

I got boat out of garage and after putting sea foam in it a couple of days ago and letting that soak in the tank a bit I decided to start it in the drive way and see how it ran.

It starts right up....but one thing i do remember was that it did idle rougher then it ever has. But I wanted to get it up to temp. and see what happened. Even though it is very hot here suprisingly it took awhile for it to reach temp. Besides idle a bit rougher than normal...nothing horrible but just more noticable to me, I was going to hop out of the boat and turn the water off to the muffs. Thats when I noticed a bit of water in the blige area.

Taking a closer look it appears to be leaking from what I would call a water pump on a car engine but it appeared to be leaking from a hole and not a gasket? I need to pull up the manual and see what exactly is leaking and what that hole is for.

Just so you know I am mechanical but pressure testing is a bit over my head. I thought about replacing the rotor and spark plugs but the realized how difficult it appeared it was to access the plugs even.

crashcourse101 · 07-18-2013, 12:46 AM

typically the hole is there to let you see the pump is bad. It should be fairly easy to change although I have no experience on the boat engines i can only assume it to be as easy as a car. And unless your motor does not like heat I would do a compression test now to make sure you didn't get it too hot and hurt the motor but I wouldn't think its related to your speed loss.

uselessgrant · 07-18-2013, 04:47 AM

The hole on the waterpump is a tattletail that the seal for the bearing is bad, replace ASAP. Automotive is fine just make sure it is for a vehicle with the same belt type ur boat has. Vbelt vs serpentine. Othewise the pump will spin backwards which will fight with your lower unit pump and cause overheat.

kemhardt · 07-18-2013, 12:00 PM

Thanks for the input and advice. That is on my list of things to fix first and then go from there.

I am contemplating fixing the water leak myself ( I can do that) but thinking I am going have to take the boat in to a mechanic to diagnoise the loss of power.

I have a week already planned at the Table Rock lake with the family the 2nd weekend of Aug. and can't imagine going there without the boat. I could set here and dink with the boat till i'm blue in the face and never solve the issue then when I really have to take to the shop they wont be able to fit me in before my vacation. I'm thinking if I get it know and take my lumps atleast I can get it back in time for the trip.

I know the boat hasn't had a good tune-up in atleast 4 years so I'm thinking if nothing else a tune-up will help.