Supercharger intermittent

Overdraught

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First trip out this year and when able, I opened the throttles fully and not much happened!

Port engine revved normally but stbd would not, so progress to planing speed was slow (and a little embarrassing with a lot of Cobbs Quay behind me!). Once running, she held high cruising speed no problem. Stopped after a few miles and started again, with no problems so thought was a one off issue. However, coming home from Lymington later, she initially failed to power up again but got to and held planing speed, so seems to be supercharger rather than turbo's. Stopped once more at Bournemouth and acceleration was swift. Supercharger seems to cut in OK in neutral.

I'm hoping it might be a belt issue but I recall when I bought the boat I had a similar problem which involved a switch. The symptoms were similar but more pronounced. This weekend we maintained 29 knots for almost the whole journey so there was little adjustment of the throttles and therefore few chances to check acceleration whilst already planing

Engines serviced October and few hours since

Could someone please tell me its something simple and cheap to fix!

thanks
 
It's something simple and cheap to fix!
...Errm, maybe. Or could be complicated and expensive.

Both engines doing the same thing, or one engine "lagging" behind in revs when it fails to take off?
 
Well, all I can say is that you were going Ok on Saturday when you went out, you couldn't even slow down for the harbour entrance!! I think I saw you off Bournemouth Pier, I was further offshore on route to Newtown Creek.
Back to your problem, first question which is either yes or no, are you down next weekend? but cheap I am not, simple yes!

Steve
 
must admit, did think I should have slowed down a bit (you're going to tell me there's a byelaw to that effect!).

Speed was good - 37.3 knots was about max so happy with that.

I'm not planning on being down this weekend - have inlaws staying. However it could be a good excuse! Could make it sunday probably. Any thoughts?
 
"must admit, did think I should have slowed down a bit (you're going to tell me there's a byelaw to that effect!)."

Yes 10 knots all year !
 
thanks, will adhere in future. Would appear not many people seem to be taking much notice, especially when I came back later that day. However, no excuse. 10 knots it is.
 
[ QUOTE ]
Yes 10 knots all year !

[/ QUOTE ]

"The Speed limit of 10 knots is applicable throughout the year, but is relaxed in the Wareham Channel, Middle Ship and North Channels only between 1 October and 31 March."

i.e. a large proportion of the main channel is not speed limited until 1st April /forums/images/graemlins/smile.gif

dv.
 
The speed limit doesn't apply in the swash channel during the off season either, so its not as far out as the training bank - only as far as buoys 9 & 10.

Me2 is correct though - from Brownsea Roads to Swash is 10 knots all year - eg a couple of hundred yards either side of the chain ferry - so I wouldn't open up as early as 16 on the way out if I were you.
 
/forums/images/graemlins/smile.gif

ANYWAY, having totally drifted this thread onto an interesting discussion about Poole Hbr speed limits, can we get back to the original posters Supercharger problems?

Things to check:
- Connector into black electrical box on top of engine. Remove, spray with WD40, wiggle around, replace, making sure locking ring goes click.
- Check / wiggle / WD40 connectors to relays & control box inside the black electrical box.
- Check / wiggle / WD40 connector to speed sensor on top of the timing case.
- Check belt tension, esp aux drive belt (smaller flat belt).
- There is also a "full throttle" position switch near the throttle arm.

Failing that, get the supercharger clutch checked out. These can fail and take out the control box on the way due to excessive current draw.

dv.
 
I promise not to mention the speed limit through the harbour entrance.
I agree with your suggestions but in a different order and one at a time so when you correct the fault you will know what it was rather than just covering it all in one go.
Hopefully it will be sorted (I wonder who?)and will report back to the forum so we can all learn from it.

Steve
 
Blimey

That makes for a good "what now skip" case.
Q: You're on your first trip of the season, and after hammering the throttles nothing happen. WNS?
A: Insist on the throttles till you get the boat on plane, cruise around at almost 40 kts and return to your home port when you're done.
Not sure many would have suggested such solution, but all's well that ends well I guess... /forums/images/graemlins/grin.gif
 
Re: Blimey

What you must remember is that the sun was shining, there was no wind and hardly any tide so why let a little thing like that get in the way!!
 
Re: Blimey

Yeah, I didn't want to suggest that Adam behaviour was totally insane, actually!
Just thinking about the difference between what we're able to work out when debating wns scenarios in front of a keyboard and what actually happen in the real world...
 

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