engie just shut down?

avon5.4 · 11 March 2007, 19:12

hi every one ive just got back from the river where we go and had to make back by aux engine as main would not start.
at first it started ok then i went for a short plod up river till they were ready to board then we set off, we went about 1.5 miles when i opened her up she went up to 5000 rpm when she just compleatley shut down, no juddering or missing. the tell tail was pumping water out as well just before it happened. the engine is a 1992 selva . i think it was down to the temp switch , as we have just put new fuel lines and glass filter and primer bulb . we checked the spark plugs but we could not get a good spark to fire her up so flattened the battery, have you any ideas please, ps is there such a thing as too much compression as weve just had it rebored and have had running a few hours in the tub and its hard work for the starter to spin it into life

PeterR · 11 March 2007, 20:48

Two strokes are quite simple you need good compression a spark and fuel with two stroke oil being delivered to the cylinder.If one of these are missing youve got a problem.If theirs doubt the oil has been delivered to the cylinder you may have seized it and by doing so now lost compression.No spark is electrical will give your symptoms.you can never have too much compression unless it uneven to all cylinders.Hope that helps.Its really crap when your engine goes wrong even worst when you have just had it rebuilt lets hope it just electrical or fuel and not to do with the cylinder rebuild

jyasaki · 12 March 2007, 00:46

Did the lanyard fall off?

Kind of odd that it would shut down completely. Sort of points away from a fuel issue, as it would have sputtered and died.

Peter; if he could test for spark and ran the battery flat, it was most likely cranking, so no [complete] seizing. Doesn't mean tha lack of oil wasn't the problem, but the abrupt stoppage would have me looking at electrical.

jky

avon5.4 · 12 March 2007, 17:26

we got it running just after getting back home we by passed the fuel filter put a better battery on it and away she went , not as good as she was before , we replaced the new temp switch with the oil one put back in the old thermostat and checked the plugs and put some brand new ones in , thats the 3rd set in 10 hours running , ive got a brand new set of fuel diaprams so will change the pumps seals i was going to take of the head to see if scorned again but theres a hell of lot of compresion so im 50/50 at that one , going to get a lorry battery to crank it over which ampage battery would be the best and last the longest ,
if i had had a knife in my hand i would have slashed it down both sides and sunk it, i think it doesnt like water , by the way ive called it NOGO

Rogue Wave · 12 March 2007, 17:52

Quote:

Originally Posted by avon5.4

if i had had a knife in my hand i would have slashed it down both sides and sunk it, i think it doesnt like water , by the way ive called it NOGO

That's a bit drastic and probably unfair on the Avon, Surely it would have been more appropriate to take a sledge to the engine! You never know it might evenmake it go better.

It's a great rib hull get an old yammie on it amd start enjoying it.

Biggles · 12 March 2007, 17:55

Agreed a Yamaha is the only way to go. A 2 stroke 80 would be fantastic on that Rig.

avon5.4 · 12 March 2007, 18:23

its got a selva 80 on it , its just getting the selva to work, any ideas to wot battery i would need i used a battery of a shogun 630 cold cranking amps to finaly crank over,the top plug colour was a rusty ish brown the other two were a bit lighter in colour , the water was coming out of the tell tail but a bit warm even though river water cold, im going to chuck the new temp switch as i think it cut out too early ?

Nos4r2 · 12 March 2007, 19:20

If you get sick of it then I'll take the whole boat away, no charge if you ask nicely

Chris · 13 March 2007, 15:28

That engine sounds like its going to be a nightmare, there are quite a few cheap ones on ebay at the moment.

http://cgi.ebay.co.uk/JOHNSON-70HP-S...em120095445388

or

http://cgi.ebay.co.uk/Evinrude-55Hp-...em200087805816

or

http://cgi.ebay.co.uk/Mercury-80-Out...em160094225962

or

http://cgi.ebay.co.uk/55-HP-YAMAHA-O...em170090219011

Chris

Nos4r2 · 14 March 2007, 08:05

Quote:

Originally Posted by Chris1573

That engine sounds like its going to be a nightmare, there are quite a few cheap ones on ebay at the moment.

http://cgi.ebay.co.uk/JOHNSON-70HP-S...em120095445388

This one might be worth a look-it's a VRO and the 70's are strong motors. Some don't like the VRO system so likely to be cheap. Also the newest of the lot.

Quote:

Originally Posted by Chris1573

or

http://cgi.ebay.co.uk/Evinrude-55Hp-...em200087805816

Avoid it like the plague. The motors used to snap conrods for a hobby.A few years back Foxhangers Marine in Devizes had a pile of dead ones, all with holed crankcases.

Quote:

Originally Posted by Chris1573

or

http://cgi.ebay.co.uk/Mercury-80-Out...em160094225962

Actually quite a good motor. The only dud blueband was the 402 40hp. Heavy,thirsty and no PTT though.but spares availability is pretty good still. The Johnson at the top probably has more power-the merc is crank rated HP and the Johnson is prop-rated.

Quote:

Originally Posted by Chris1573

or

http://cgi.ebay.co.uk/55-HP-YAMAHA-O...em170090219011

That's way too much money for a non-runner that needs parts.