Broom Javelin transom rating

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Dan
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Broom Javelin transom rating

Post by Dan »

Hi all, first post on the forum. Great place for info over the last few years so decided to join. I will become a member soon as well.

I have bought a Broom Javelin, think its a mark 1, 1960 model. It needs restoring and work has commenced! To me its a mild restoration as it was dry stored for many years, and the general condition is very solid and good - no rot at all. But it does need a screen/frame, engine, new steering, etc...

I was talking to a friend and they have a 55HP evinrude, 737cc, year 1980 outboard. I have seen a 50hp on a Broom Javelin, so I am happy enough to fit it, but does anyone know what the transom on these Broom Javelin boats was rated at? Ideally someone may have an old spec sheet or advert that states this?

Thanks! Dan

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Alacrity
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Re: Broom Javelin transom rating

Post by Alacrity »

I had a Javelin for a while & it ran very well with a 40hp Merc on it but became a handful, & in my opinion overpowered, when I put a Merc 50hp on her.

Care needs to be taken with these old wooden Brooms as the glue that they were built with tends to come apart & the glue ends up looking like dry marmalade. Mine did it & I have seen others do exactly the same if driven fast, so be careful. They are easily repaired but dangerous if left.

Oh & welcome to the forum!
Mercs are like women, no 2 are exactly alike. That's what testing is about. In general it is safer to test motors and props than women!

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Rapier
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Re: Broom Javelin transom rating

Post by Rapier »

Hi & welcome - am fond of the Javelin, despite it's reputation...The maximum rating for a Javelin is 40hp, which will put it in the 30mph bracket. They're a flatish bottom boat, so unless is dead calm it won't be fun at speed either. A 55hp Evinrude has an advantage over a 50hp Mercury, in it's lower CofG, but as Alactrity says (and I saw the 50hp runs he did) is a handful. The 55hp may also be prop rating, rather than powerhead rating too. Worth bearing in mind your insurance could also refuse to pay out, in the event of accident, if you overpower it.

The weak spot on these is their bottoms, so look for corroded keel / rib / seat mounting screws (mild steel) and the dry 'marmalade glue' referred to, especially if it's been stored dry for years.
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Alacrity
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Re: Broom Javelin transom rating

Post by Alacrity »

Rapier is correct about your 55hp motor probably being prop rated - this takes it even higher than the 40hp max limit as that 40hp would have been crank rated so only about 30 - 35hp in todays prop rating. If you use the same, old style, rating with your later motor it would probably be rated around 60 - 65hp so quite a lot above the Javelin's rating.

I hope this makes sense!
Mercs are like women, no 2 are exactly alike. That's what testing is about. In general it is safer to test motors and props than women!

Dan
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Re: Broom Javelin transom rating

Post by Dan »

Thanks for the replies, I am glad you two have replied as I have been reading your threads and watched the video when I done a search last week.

I got the Evinrude as it was part of a deal with a good friend. He had a Shakespeare speedboat sitting in the yard on a trailer with the evinrude on the back with remote. I got the lot for a sensible price, so just need to sell the hull/trailer now the outboard and controls are removed. Its the wrong era (1980) was my only objection! And after watching the video with that 50hp on the back...well it looked fun to have the power on tap. i totally understand what you are saying about cranck and prop hp. Was not too sure what year they changed that? But this is a 1980 engine as I checked the model numbers of it on evinrude website.

The outboard needed some wiring renewed and also the starter is missing. I have nearly sorted out the wiring, and intend to hand recoil the engine to see if it starts and runs well. Its got good compression and I think it will run fine. Once it does (fingers crossed) I will buy the starter motor and also a new loom. I can then consider selling it to buy a 40...May give the 55hp a go to see if I like it if im honest, at least I am tempted...but safety first on the water is always a number one rule - so its looking like its too over powered and will be sold on!

I have restored a few classic boats, this is the first speedboat, smallest project boat I have had to date. I have some west epoxy from the last restoration job on a double diagonal hull. How do you recommend the strengthening is done on one of these hulls? It is very solid all round, inside and out, I have just stripped the keel and west epoxy treated that, approx 2 to 3" eitherside of the keel all the way to the front waterline. I did consider stripping the complete bottom of the hull and treating the whole lot with West epoxy, but it just wanted fairing up. I removed paint and filler from all the screws and checked them. The heads all looked well, so i epxoy filled them.

I will get some pictures up for you to see. Thanks for the replies so far, excellent forum!

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Re: Broom Javelin transom rating

Post by haventaclue »

It changed from block to shaft rating in the early '80's,around '84 for most of the outboards.As your is '80,then it's BHP
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Re: Broom Javelin transom rating

Post by Dan »

haventaclue wrote:It changed from block to shaft rating in the early '80's,around '84 for most of the outboards.As your is '80,then it's BHP
Just about to get of the forum and google that, so thanks for the info. I just added a post in the restoration projects section. I am seriously thinking that I may just have to fit this 55hp and give it a try!

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Re: Broom Javelin transom rating

Post by Rapier »

I see from the motor that it's a short shaft, which makes it worthwhile keeping - if you get the classic boat bug. The Shakespeare it came off is also considered a classic and very capable sea going boat and if it has a short shaft transom model, is probably late 1960s - it would go very well with the 55hp. There are 6 or 7 Shakespeares in the CMBA, all used as 'rough' water boats, 2 of the Mini Clubman model (I think yours is) have late model 50hp Mercurys (rated 45hp at prop).
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Dan
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Re: Broom Javelin transom rating

Post by Dan »

Rapier wrote:I see from the motor that it's a short shaft, which makes it worthwhile keeping - if you get the classic boat bug. The Shakespeare it came off is also considered a classic and very capable sea going boat and if it has a short shaft transom model, is probably late 1960s - it would go very well with the 55hp. There are 6 or 7 Shakespeares in the CMBA, all used as 'rough' water boats, 2 of the Mini Clubman model (I think yours is) have late model 50hp Mercurys (rated 45hp at prop).
The shakespeare is not too bad at all, it wants a polish up on the top. But I have no room for both as I share the workshop with my brother in law (not much sharing at the moment as its full of my stuff!). It will make a good boat, didnt know much about it either...I just got the engine off and asked my bro in law to get it listed on the internet asap - purely down to space. Im hoping I can get at least £350 for the hull and trailer. Just put new tyres and bearings on the trailer. The tyres cost £70 fitted (10") and the bearings are mini car type, cost £78 +VAT. It should make a nice project for someone.

The short shaft evinrude is why I bought the package, was hoping the trailer would be useable as its bunked, but its too small unless I weld an extension by approx 2/3ft - Im considering a galvanised alko chassis then build on that to have it specially designed for the boat, or a decent boat trailer if I find something suitable. The general idea is to try and get her on the water this year.

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