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Old 14 July 2011, 22:32   #1
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Tohatsu 9.8 tell tale (pee stream)

Hi Folks

I have just replaced the impellor on an old but low hours engine as it had not been run for some time. On running the engine the tell tale splutters water out ! I was expecting a constant stream.

Is this normal or should I check the new impellor/water feed pipe?

Regards


Mike
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Old 15 July 2011, 06:22   #2
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Telltale (pee stream) solved

I have a Honda BF50. From time to time even after impeller change the outlet for the telltale will become clogged. Follow the hose from the engine cover to where it enters the engine block and use a small gauge wire to clear the hose and fitting. it works for me every time and restores my confidence in the performance of the water pump/impeller.
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Old 15 July 2011, 07:38   #3
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Mine has two places where water is ejected - one facing down at the rear of the motor which sprays a loose jet of water downwards behind the leg and the telltail which spurts a discreet but powerful jet to the starboard side, low down from near the rear of the casing. The hole is very small and mine was blocked when the motor arrived, a good dig about with some fine wire sorted it out - there were bits of shell and grit in it.
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Old 14 August 2011, 21:39   #4
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Pee Stream

Thanks all for the reply's. Wilks I have only the rear discharge on my engine no discreet side port. However being unhappy with the situation I removed lower leg and checked water pump assembly. Somehow one of the studs fixing the water pump was loose. Anyhow after rollicking myself, re-assembled and now pee's like a trooper after a night on the ale.

Thanks all.


Regards


Mike
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Old 14 August 2011, 21:54   #5
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Quote:
Originally Posted by tidalwave2.7 View Post
Thanks all for the reply's. Wilks I have only the rear discharge on my engine no discreet side port.
Good to hear you're sorted. Is it a 9.8B 2 stroke or a 4 stroke? Mine is the 2 stroke (2006), the port is VERY small!
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Old 14 August 2011, 22:23   #6
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engine

2 stroke,not sure of age as has been in my farthers garage for years. I have pulled it out and given it a minor service. Impellor,plugs and gear box oil. It runs well and and I will be taking it to Anglesey for its for outing on the small rib in about a week. Definatly I have only one water outlet. Maybe the design changed as your motor is more recent than mine.

Not sure what to expect re speed etc but is just for fun so as long as it produces a grin am not too worried.

Managed to put the whole rig togather for peanuts as engine was free and boat bought form a bankrupt stock reseller. Trailer form fleabay. Working on the basis of less cash more smiles. Hopefully it will be mad as a box of frogs.

Main use if just to have fun off the beach and possibly a little fishing etc.
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Old 03 September 2011, 06:40   #7
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Tohatsu 9.8

Boat launched on the Menai Straight although it starts first pull the performance dissapointing.

Struggles to get on a plane with 1 adult and a child. Engine rev's fine etc. As the boat is a very small rib I was expecting it to pop up on the plane without too much trouble.

A friend managed to get it onto a plane solo but he really had to work at it. Could it be a prop issue.

Not sure how to identify the pitch etc and boat has been left in Wales while I have the trailer modified. Does anybody here have experiene of changing the prop pitch etc on a small engine like this.

Regards


Mike
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Old 03 September 2011, 07:56   #8
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What boat are you putting it on? What was the engine on before it was on this rib? It is possible that it is not propped right for the job. However what is the boat? 9.8 is not a lot of power for a rib unless it is really tiny.

When you say it won't plane, what happens? e.g. bow points to the sky, boat struggles with the engine labouring etc. When your friend managed to get it on the plane what did he do? Once it was on the plane was it easy enough to keep it there? Did you try "playing" with the trim pin?

The prop pitch is usually marked on the prop. You may need to remove the prop to find the marking. If you find a marking but it doesn't make sense try posting it here for someone to "translate".
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Old 03 September 2011, 08:23   #9
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Is yours this small rib?

http://www.btowstore.com/WebRoot/BT3...E54/0fe1_1.jpg

If so, having owned a 9.8 Tohatsu and used it with a 3.1m old Zodiac SIB that weighed the same, it should easily plane with one adult and one child. Mine would plane the Zodiac at 16mph with an adult and two children or two adults. From a standing start it would only take a few seconds to rise over the hump onto the plane.

To be honest the prop, assuming it's the standard one, isn't so critical to stop you planing. Another guy here had just the same speed problem recently with a 15hp only to find after loads of discussion that his outboard was only firing properly on one cylinder.

BTW your standard prop should be marked something like F8.5 for an 8.5" pitch.
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Old 03 September 2011, 13:34   #10
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off the plane

The boat in question is a tidalwave 2.7m rib. It is as the picture. The plate on the boat indicates a weight of about 65KG. The engine weight is 26 KG with fuel tank and fuel at about 16KG.

So not a heavy package. As for the prop I believe it to be the standard prop, although I will check it out when I get the boat back from Wales. The engine is a twin and seems to run very smoothly it has no indications it is running on one piston etc.

When it planed it was coming into shore with the sea behind it. From my experience it seems to squat at the rear and push the nose up. This I could understand if it was a transition phase but it does not seem to overcome this phase!

I have purchased a tiller extension and hope to have another go next week. when I will also check out the prop.

Regards


Mike
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