Help Please. shear pin advice.

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Runna

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First of all i hope i have posted in the right section....

on sunday was using my outboard on a friends boat after it had broke the mooring.

engine was running fine untill all of a sudden i believe my shear pin had gave way.. showing the signs, will rev up but prop will not spin under water but will spin out of water.

so i am just woundering if some one can point me in the right direction to where i can get a pin for my 15hp mariner 2 stroke long shaft engine.

i dont know what year it is but im guesing 1980's? it is the greyish silver model and the stickers are orange band with a thin black outline and then i thicker white outline and the mariner writing is above it also in white.

Thanks in advance James
 
Runna said:
First of all i hope i have posted in the right section....

on sunday was using my outboard on a friends boat after it had broke the mooring.

engine was running fine untill all of a sudden i believe my shear pin had gave way.. showing the signs, will rev up but prop will not spin under water but will spin out of water.

so i am just woundering if some one can point me in the right direction to where i can get a pin for my 15hp mariner 2 stroke long shaft engine.

i dont know what year it is but im guesing 1980's? it is the greyish silver model and the stickers are orange band with a thin black outline and then i thicker white outline and the mariner writing is above it also in white.

Thanks in advance James
Click to expand...

I bought my last ones from Ebay, only a few squids. (little put-put 2.5)

Most larger chandlers should stock them on the blister pack stands. I know one chap who swore by welding rods but I am happy to buy the proper type as they are normally scored to create a break point. I just looked on Ebay and couldn't see any, ho hum.

I don't know where you are, but I know http://www.llynmarine.co.uk/ will mail order (they are very good).
 
Your owners manual should tell you about the shear pin. If you have mislaid it down load one from the download center at Brunswick marine

http://www.brunswickmarineemea.com/download/main;jsessionid=1fehkmrsqagri?type=corp

There's a year identifier on there as well.

Also just in case does the motor have rubber bonded hub to the prop that could have failed. Usually will drive at slow speed but slip at any attempt to open up the throttle.

If the prop will spin by hand when the thing is in gear then its the shear pin !
 
was thinking about using a steel rod just tempory but the harbour where my boat is there are sand banks and also alot of unused morrings. so i dont want to risk it if i get caught and the steel rod or bolt dont snap then my gear box may go so dont want to be spending alot for the sake of soucing a sheap pin and they dont cost alot i believe
 
Runna said:
was thinking about using a steel rod just tempory but the harbour where my boat is there are sand banks and also alot of unused morrings. so i dont want to risk it if i get caught and the steel rod or bolt dont snap then my gear box may go so dont want to be spending alot for the sake of soucing a sheap pin and they dont cost alot i believe
Click to expand...

They are not expensive but if you are somewhere subject to constant "prop hitting something" syndrome it might be prudent to identify the metal and diameter, usually brass, and buy some rod and cut a few of your own as it will work out far cheaper in the long run. Also, buy a couple of spare prop nuts and a few spare split pins - you're bound to drop one or two over the side whilst changing a shear pin afloat. One more tip, get a length of nylon line or string and tie this tightly to one blade of the prop before removing it if you're afloat at the time. Naturally, tie the other end to a cleat of course, as that will stop your prop going "deep six" as well!
 
i snapped mine on a honda 2.3 this year but had a one go on a honda 8 ..i always have a few boxes of different thicknesses/sizes of pop rivets and the snapped of pins , Choose size to suit, work a treat when snipped off to length.
 
Cliveshep said:
They are not expensive but if you are somewhere subject to constant "prop hitting something" syndrome it might be prudent to identify the metal and diameter, usually brass, and buy some rod and cut a few of your own as it will work out far cheaper in the long run. Also, buy a couple of spare prop nuts and a few spare split pins - you're bound to drop one or two over the side whilst changing a shear pin afloat. One more tip, get a length of nylon line or string and tie this tightly to one blade of the prop before removing it if you're afloat at the time. Naturally, tie the other end to a cleat of course, as that will stop your prop going "deep six" as well!
Click to expand...

the engine is not that heavy so i can lift it off the transom. going to bring it home this week end so i can have a look. do you think stainless steel rod would be ok?
 
safer with brass rod same diameter.
buy a length and cut yourelf off a set.
I did it with a set of 15 and 20 HP engines we had in a school rowing club some 30 years ago and not one of them let us down...... in fact I think they were old brass stair carpet rods which were from between the wars originally.. :-)
 
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Shear pins

In my experience the most likely scenario for breaking a shear pin is when the engine gives trouble starting and you finally get it going. You slam it into gear at excessive revs so that the inertia of the prop snaps the shear pin. I doubt it would snap under normal acceleration under load. As said it might be jumping out of gear or the rubber bush in the prop has become detached.

Incidentally I found on the Johnson that the shear pin breaks in 2 places so if it is removed and replaced with only 2 of the broken sections and a gap in the middle you can get drive in an emergency. Failing that a large nail cut down to length will also do. However with just a little care re engine speed on engaging the gear and you will never break a shear pin. good luck olewill
 
thanks for the advice guys, going to get my self some rod asap but for now i have found a drill bit the right diameter so going to use it tempory,

im having trouble finding the year of my engine as my serial number plate has got damage to it.

any one have an idea what year and model it is? i have been told its a w-15 and is around the 1980's year.

heres a picture it has been resprayed at some time and to me it looks like its a little bit darket than original

11469_102134676479088_100000476685371_56503_211546_n.jpg


Thanks James
 
Based on experience I'd encourage you to get the actual manufacturers spare. We didn't & ended up with a new prop too! Long story, but a cautionary tale. Oh! and take split pins too
Tape a spare shear pin and a split pin somewhere on the engine too - or attach them to a pair of pliers and make sure the pliers and the engine travel together.
When you have a genuine spare then look at sourcing a replica
 
Sound suspiciously like you may have bought a dodgy engine ,there is not a chance in normal use that the serial number would be damaged,and a repainted cover likewise,except to ensure it is recognisable if stolen.
Just a thought!

inat182
 
i am 99.9% its not a dodgey engine it has been on the same boat for years in a compound then my mate bought the package cheap and offered the engine to me. surely they would of taken the serial plate off if it was stolen etc. it looks like it has been dropped and hit something the way it is damaged
 
Making your own sheer pins.

I certainly make my own .... no-way am I paying over £1 for each pin! (4mmx24mm).

I'm surprised that no-one has mentioned that home made brass pins need to be hardened after cutting to size so that they snap cleanly. Just heat to cherry red and plunge very quickly into cold water.

(I can go for ages without breaking one; .... then get through several in a day!! - usually when beaching the dingy in an unfamiliar place).

Vic
 
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