Logo
FULL SITE MENU

50 220hp Reduced Revs and Top Speed

M

mrgrumpy

New member
"I would be grateful for any s

"I would be grateful for any suggestions. I purchased my first boat at the beginning of the year...1999 Searay 260 Sundancer with a 5.0 Mercruiser 220hp.

Becaused of the appauling weather in the UK the boat has only been used 4 times since purchased. Recently I noticed that the battery wasn't holding charge whilst moored and promptly replaced it for a slightly higher spec battery.

Yesterday we took the boat out for the first time in a while and I found that it would not rev passed 4000 rpm, which was only giving a max speed of 25 mph. From my brief experience I believe that the boat used to run at 5000 rpm, giving a top speed of 32+ mph.

Does this sound like some mechanical issue or could it be in someway connected to the changing of the battery? It does seem a little coincidental....

The only other thing I have done is topped up with fuel.

Thanks in advance
Mark"
 
"Doing 5000 is pushing the eng

"Doing 5000 is pushing the engine very hard. It would appear that with a full tank of fuel and other bodies on board you increased the weight of the boat which would also slow it down. Issues like wind, surf and undertow are also reasons why you would not consistently hit that rpm. I would caution you about pushing it that hard."
 
you said boat sits a lot. is t

you said boat sits a lot. is there lots of fouling on the bottom? battery should not affect speed. check that you haven't knocked a plug wire loose. check fuel filter for water.
 
I guarantee you the boat is lo

I guarantee you the boat is loaded with fouling and crud! My boat looses a couple mph after sitting a week.

Geoff
 
"Thanks very much for your inp

"Thanks very much for your input... I've just realised that my comparison was made against the start of the season when the hull was totally clean. I'm also thinking that the loss in performance is not sinister, but just a build up of Crud (fastjeff) which will soon be rectified. Thanks again."
 
.."a build up of Crud &#40

.."a build up of Crud (fastjeff) "

I am not some kind of crud!

Jeff

PS: Hope that's it.
 
Back
Top