longshaft?

Horsley-Anarak · Post by **Horsley-Anarak** » Mon Jun 22, 2009 11:39 pm

Just spotted your problem Neil, it was not three days in a boat but "three men in a boat"

Hear you might have a suitable Thames venue for a bit of a gathering?

H-A

P.S. Break it to Charles L gently that he will never get on the plane

Post by **Charles uk** » Mon Jun 22, 2009 11:48 pm

Neal I'll wager 50p, that on the right hull, with your SD "running right" I can get on the plane, without any spanner tricks to your motor.

Shall we give it a go, if we get to meet up on the river?

rosbullterier · Post by **rosbullterier** » Mon Jun 22, 2009 11:51 pm

Oh for goodness sake - poor old gc is taking all this machining from the thwarted marine engineers seriously while the truth is - you've got the wrong engine for the boat!!!

The Seagull Plus has a bloody great big propeller with a low ratio box to make it push heavy barges slowly.

The size of your 11 inch prop added to the size of the Plus gearbox added to the length of a longshaft tube means yes it will drag along the road off the back of your dory - because you need a nice standard shaft Century with the standard size four/five blade 9 inch prop.

There. - well there's been sod all to comment about for a while . . .

Got my two TC water pump housings back today with 3mm CAD machined from their bases ready to take the anti ventilation plates for the cat twin setup . . .

timberman2004 · Post by **timberman2004** » Tue Jun 23, 2009 7:33 am

Well, as the gauntlet has been thrown down ..A gathering on the Thames it is !!!

now lessee ....Charles reckons a 50p wager to get my SD running right ....Hmmm worth losing the bet

If I bring the whole flock and bet on the same basis, that'll be £ 7-00 lost wagers ....for the whole flock to get fettled

Sounds worth it

Abingdon Marina has a tight little slipway but its public and best of all, has loads of parking ...still to check out the ferry lane one @ cholsey

google electric boat association ...great info on Thames slipways there

anyone else coming ?

Post by **Charles uk** » Tue Jun 23, 2009 8:31 am

NO NO NO Neal

I said without fettling,
all that will need to be done,
is half the prop blade area, so that we can get the revs up to warp factor 8.7,
your dilithium crystals should be plenty good enough, for such a weak gravitational field.

And if we can't find any worm holes I could drill some.

sparky · Post by **sparky** » Tue Jun 23, 2009 2:45 pm

I would just like to say I'm a member of a reef keeping forum and we always go off topic. It's nice to see you guys do on here too. lol

Todd · Post by **Todd** » Tue Jun 23, 2009 3:45 pm

"... you'll NEVER get on the plane .... "

Not so Timberman -

My 40+ will plane my very lightweight 12' aluminum jon boat, but once on plane, turns about 4650 rpm. I think I need a little more prop.

On a remotely related topic, I tried putting a screw in each of the exhaust pressure relief holes in the exhaust tube and was astounded by the quieter and seemingly smoother running, especially at lower rpms. Most importantly, starting and idling were absolutely unfazed. The only trade-off was a tiny bit less power at full throttle - I had to scoot my arse a bit farther forward to get up on plane.

Is there any danger of harming the engine over the long term if I leave those holes plugged? Anyone?

Post by **Charles uk** » Tue Jun 23, 2009 5:36 pm

Todd can we have your engine number?

Which prop do you have & how fast are you going & what do you weigh?

Your doing well to plane with a 40, Congratulations!

grahamcamm · Post by **grahamcamm** » Tue Jun 23, 2009 5:44 pm

rosbullterier wrote:Oh for goodness sake - poor old gc is taking all this machining from the thwarted marine engineers seriously while the truth is - you've got the wrong engine for the boat!!!

The Seagull Plus has a bloody great big propeller with a low ratio box to make it push heavy barges slowly.

The size of your 11 inch prop added to the size of the Plus gearbox added to the length of a longshaft tube means yes it will drag along the road off the back of your dory - because you need a nice standard shaft Century with the standard size four/five blade 9 inch prop.

There. - well there's been sod all to comment about for a while . . .

Got my two TC water pump housings back today with 3mm CAD machined from their bases ready to take the anti ventilation plates for the cat twin setup . . .

I was allways under the impression that a 20 inch transom required a longshaft. The boat isn't just a standard dory, it's a seahog probably weighs over 300kg and is only being used on windermere with a 10mph speed limit on the lake.

Vic · Post by **Vic** » Tue Jun 23, 2009 7:07 pm

was allways under the impression that a 20 inch transom required a longshaft

You are correct. With "performance" engines the rule for the depth/mounting height is shown here: www.smalloutboards.com/shaft.htm

With your Seagull you need to ensure that the water-pump housing is always submerged or you will lose cooling.

If your transom top is 20" above the water level shortening your engine as suggested or fitting a standard shaft engine will not only raise the water pump above the water level but part of the prop as well.

If in fact you find that the top of your pump housing is more than 5" below the water then a standard shaft model will ft your boat.

grahamcamm · Post by **grahamcamm** » Tue Jun 23, 2009 7:16 pm

Vic wrote:
was allways under the impression that a 20 inch transom required a longshaft
You are correct. With "performance" engines the rule for the depth/mounting height is shown here: www.smalloutboards.com/shaft.htm

With your Seagull you need to ensure that the water-pump housing is always submerged or you will lose cooling.

If your transom top is 20" above the water level shortening your engine as suggested or fitting a standard shaft engine will not only raise the water pump above the water level but part of the prop as well.

If in fact you find that the top of your pump housing is more than 5" below the water then a standard shaft model will ft your boat.

The bottom of the cavitation plate is 3" below the bottom of the boat. Where is the water pump housing in relation to the cavitation plate?

Vic · Post by **Vic** » Tue Jun 23, 2009 9:55 pm

The waterpump housing is the section immediately below the drive shaft tube. The horizontal section between the drive shaft tube and the exhaust tube

Todd · Post by **Todd** » Tue Jun 23, 2009 10:01 pm

Charles uk wrote:Todd can we have your engine number?

Which prop do you have & how fast are you going & what do you weigh?

Your doing well to plane with a 40, Congratulations!

FPL942KK5. I cut it down to FP specs. Standard 9", 4 blade prop. I weigh about 170 but my boat only weighs around 85 lbs, aluminum with a square front and flat 32"wide bottom. We call them jon boats. I'd post a pic if someone would explain to me how to do it! I'm not sure of the speed, maybe 7-8 mph.

Interestingly I bought this motor very cheaply as a spare parts donor for my other 40+, FP758MO. But it turned out to be a low time, corrosion/rust free, fresh-water-only example, much more powerful than my prized first one, which definitely won't plane the boat.

Vic · Post by **Vic** » Tue Jun 23, 2009 10:35 pm

I'd post a pic if someone would explain to me how to do it

Open an account with Photobucket or similar. Upload your photos to there but keep the size down to "large " or 15" screen"
Copy and paste the "IMG code" that appears below the thumbnails when "moused over" into your post. The picture will appear.

Got many, then tick the little boxes below the thumbnails scroll down hit "Generate html and IMG code". Copy and paste the code for clickable thumbnails.
Clickable thumbnails appear in yor post

In both cases check in preview>

timberman2004 · Post by **timberman2004** » Tue Jun 23, 2009 11:06 pm

Cuh ..I dunno, you guys out there

1st off Charles wants to renege on his offer to fully service the flock for £7-00 ...So may all his new plumbing explode once up to pressure

2ndly, all this transom & depth stuff to exactly the 3rd nipple on the inside left turn as seen from the counter-clockwise position ..cor, what a load of turnips !!!!

I have an adjustable engine transom thingy and happily plunge the gulls DEEP down, merely keeping the HT lead just clear of the water ..this just to get them out of the way of the Mizzen boom banging on the filler cap
In my humble opinion, doesn't make a blind bit of difference

But of course i'm talking about a REAL boat
700 lbs bare, gaff rigged tops'l cutter yawl (ask Mr Google), where my 'gulls are as but as an lovely adornment, as a pearl necklace on a pretty girl ....er..um.. no, er..I think I meant a diamond necklace

Now, for you lot who want to go boating on a blueprinted, lowered and widened tea tray, with Go Faster stripes and speed slots ...well, what can I say ????

BTW ...for those who give a toss, 1942 SD now all sorted..a plug lead !!

Now runs like a sewing machine ...and was it Vic, H-A, 40TPI, who mentioned it ? ...they DO NOT like running in a tub having to breathe in their own fumes ...
Funny that, after 10 pints of best bitter and a curry thrown in for good measure, oddly, never seem to mind the resultant 'fumes' issue
HID however seems to have an entirely different take on the matter !!
oh well, ...spare room again

Have installed a fan !!!!