dory 11ft and yamaha 9.9hp

[polotche]

Hi,
The water in the hull it's a problem but I don't have time to take care of it right away
finally, I put on sale the yamaha because it's too small in the end
I saw this engine as a replacement


It's a old 25hp tohatsu, it starts very well and it's a short shaft

 

[polotche]

Ok the tohatsu is sold
I try the yamaha with the new settings and I see
The Yamaha is a good engine so I am annoyed to sell it
I hurried up

 

[polotche]

Hi,
I made a try again and it's better. The boat behaves better but my speed is always the same
When I put more on the front, I gain in speed

For the engine, I'm always at 4000rpm in charge but 8000rpm stopped

What to you think about that??

I will load the front of the boat and start again...

 

[Sea Rider]

Is it possible to post a lower leg picture shot sideways exposing both vertical plates to have a look, boat should have weight evenly distibuted on deck. Remove all gear, sit a boating mate up front and test again with OB sitting at 90?. 4K is still way low, firstly need to height sit OB properly, once there go for a prop paximization to pull wot revs further up, combo will plane faster guaranteed. Ideal would be to empty all that water that has been logged on hull...

Happy Boating

 

[polotche]

Hi,
I didn't understand everything including the photo you want?
Can you explain me with a photo or something else?

Thanks a lot

 

[Sea Rider]

Sorry to reply late mon ami. Post 37 has a link, click on it, try to duplicate on your boat/OB set up for water flow to pass under upper small water plate, don't know if in need to raise or lower OB, for that must visually check what's going at back transom. This is the fastest way to determine what need to do.

Happy Boating

 

[polotche]

Hi
Ok thanks searider. I work on my boat tomorrow so I would take pictures
I buy a new prop at a very good price
Thanks again

 

[Sea Rider]

Andre,
Found a Yam lower leg...

That's the Tip Top OB/transom height your Yam needs to work well with the least possible drag on lower leg, once dialed go for a wot spin on calm water and check how does your new prop performs with 2 up, sit one up front to have a well balanced combo. Report your max wot rpm achieved, ideal would be for OB to rev around middle to max wot rpm range.



Happy Boating

 

[polotche]

Hi,
today, I repair again my dell quay. For my engine, here are some pictures




It is at the highest
and I advanced the steering wheel to better distribute the load

I think try it all tomorrow

 

[Sea Rider]

Is water still lodged inside hull ? good to have moved center console up further, when boating alone will be much better to get out of the hole faster at full throttle.



Try to duplicate on your Yam lower leg for water flow blue line) to skim right under the yellow line. What like about Yam lower legs is that there's a nice distance from upper to lower plate, as opposed to other Jurassic OB's which have very short plate distances to play with.

Go for a wot spin preferably on morning calm waters, have a boating mate to check once combo is on plane to determine what's going on at back transom, report your findings, luckily have built a nice SS transom riser, it's a matter to adequate the wooden shim for OB to sit right at Tip Top height spot.

Happy Boating

 

[QBhoy]

Hi polotche

It's a shame you haven't managed to sort out the problem yet.
I'm not totally certain, but it looks like your prop is much bigger than he average size for that engine.
Also, as I presumed earlier, I'm glad you got the water out the hull....problem with this is that once there is water in there...it can take a while to totally dry out. You might find that your hull has absorbed a fair bit too (can be like a sponge in extreme cases) and may be holding 10's of kilo's of water and weight.
Anyway, I've had a few beers and can't be bothered looking back to see if you said what specs your prop was or not (I'm on the mobile, so not easy)...point is, it looks very much like it's for a bigger engine diameter wise.

 

[Sea Rider]

QBhoy,

A pic doesn't say much as won't have the slight idea of its real size. When posted a 18 HP close up pic, somebody said was nuts to run 50 HP props on underpowered OB's lol!!.

Ideal before going for OB height optimization along a pro maximization would be to take out all water that's lodged, with a heavier combo will need a less pitch prop to pull wot rpm up as opposed to a lighter combo which will need a + pitch prop for that enterprise.

Happy Boating

 

[polotche]

Hi,
finally, I sold the yamaha and I buy a 20hp Johnson. The johnson is 3 centimeters shorter
I try it quickly
Thanks