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Old 26 October 2004, 21:26   #1
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Any tips for taking "open" engine back into service?

So, my new parts have arrived, back in late august i'd hope that i would get them within a week or two.. turns out to be a month or two!

All this time, the lower unit has been sitting without oil (however, with plugs in) and sparkplugs removed, and carb drained. Do you think it might be worthwhile shoving in some 3 in 1 oil just for the sake of it? to get the piston rings freed up again? I only have one fueltank so cant really mix a oilrich fuel up because the tank has about 20L in it at this moment...

wil to much oil harm it? or will it just burn off as black smoke in our lovely greenhouse polluted ozone layer thingemie in a SSSI area?

Help appreciated.

Thanks,
Daniel
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Old 26 October 2004, 22:03   #2
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Daniel, put the plugs in and fill the gearbox (from the bottom) and fire her up

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Old 27 October 2004, 00:49   #3
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i semi remember cleaning the cyclinders with something... and i expect all lubrication that WAS there has now gone, perhaps prime it and pull over a few times until petrol gets into crankshaft housing?
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Old 27 October 2004, 13:21   #4
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Daniel,

As Pete says just fill the gearbox and fire her up - nothing to worry about. If your using pre-mixed fuel and its been sitting for a while give the tank a gentle shake to make sure the oil/petrol’s mixed.

I certainly wouldn't put 3in1 oil in anyway - use the same oil you mix with the fuel.
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Old 27 October 2004, 13:31   #5
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Quote:
Originally Posted by Mr-d
i semi remember cleaning the cyclinders with something... and i expect all lubrication that WAS there has now gone, perhaps prime it and pull over a few times until petrol gets into crankshaft housing?
If you wish to be cautious (no problem with that) then prime cylinders with a little of you oil used for mixing, turnover with plugs out then refit plugs and go for it. Whoops nearly forgot put oil back into the gearbox

Good luck.


Brian
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Old 08 November 2004, 13:15   #6
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Okay, gearbox is filled up (someone needs to redesign the quicksilver tubes / Mercury filling system.. no wonder you need 2 tubes, as half a tube leaks out during fill!)

Managed to fit the coils with some Ty Rips, put a piece of squishy rubber foam under them to absorb any vibrations/movement (and to stop them breaking) Fitted the new cables/sparkplugs, turned it over a few times with the sparkplugs out.. 2 very healthy looking nice sparks!

Stuck the sparkplugs back in.. primed the thing, left the cables off and tried to turn over... the first few times i managed to get the flywheel to rotate halfway (and then solid on compression/friction), took the plugs out again, sprayed some mixed petrol down the hole... turned it over freely again, stuck the plugs back in and pulled, this time got 1,5 rotation out of it... but im still to scared to touch it.. if i cant even rotate it by hand (By pulling) how in earth will it start without yanking the cord out of my hand, and smashing my hand up against the cover (which has a VERY sharp edge!)

im a bit reluctant to start it as the last thing i remember of it is backfiring + when starting pulling over was very easy

Any more solutions to a stiff outboard engine? i think i used engine degreaser in it which eats the carbon away.. and the carbon must be floating around inside around the pistons.... 3 in 1 seems a easy option! or should i try some sunflower oil or something?
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Old 08 November 2004, 14:03   #7
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Before we go any further, how old is this engine and wots it worth to you ?

Looks like you have a choice, pull start the thing or pull it to pieces, but I am not sure you are going to be able to rebuild it and manage to get good seals around the crank cases, needed for compression if its old.

You could try double mixing a small quantity of petrol and just go for it. When the engine fires you know that the oil/petrol is getting to the crank, bearings and up into the cylinders.

The pull start should not pull you hand back into the engine, but it might hurt if you get one piston top dead centre,

Pete
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Old 08 November 2004, 14:11   #8
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Umm, just spent 220 quid on it (well, my mum did.. she's a bit angry with me for spending 220 on it) but then again its a 1978 engine... and when it worked it worked like a tank... (and that was with broken coils!)

i think ill just give it a yank, wear a big glove and hope it wont backfire, locking the starting mechanism up and drawing the cord it at approx 1M/s or something (It has done it before..... and each time i managed to get my hand off JUST in time)

Okay.. where are my skiing gloves...
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Old 08 November 2004, 14:36   #9
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Riiiiight.. just tried.. no pull cord jerked out of hands (even though i was wearing gloves! )

Emm, backfire through exhaust sending water flying approx 6ft high... my guess is either the ignition that is to late, or excess of petrol that lights up when the exhaust port is "Open" causing what is in the cylinder to set alight to whatever is in the exhaust, creating backpressure failing the cylinder to take the next wave of fuel in.....
So, we got Air, we got fuel, we got a spark and we got a bang... but something in that chain is wrong

or is this something else?

Thanks,
Daniel.
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Old 08 November 2004, 14:52   #10
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Quote:
Originally Posted by Mr-d
Riiiiight.. just tried.. no pull cord jerked out of hands (even though i was wearing gloves! )

Emm, backfire through exhaust sending water flying approx 6ft high... my guess is either the ignition that is to late, or excess of petrol that lights up when the exhaust port is "Open" causing what is in the cylinder to set alight to whatever is in the exhaust, creating backpressure failing the cylinder to take the next wave of fuel in.....
So, we got Air, we got fuel, we got a spark and we got a bang... but something in that chain is wrong

or is this something else?

Thanks,
Daniel.
Silly question but have you connected the new coils correctly?? backfire could be because there in the wrong order!

Brian
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Old 08 November 2004, 15:05   #11
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Yep, wired in the way it was already wired in.. and correct according to manual except i have no idea what is cyclinder 1 and 2

anyway, if it was wired the other way round i would possibly have bits missing from my fingers by now i think its just an excess fuel burning in the exhaust when it opens creating a backpressure higher than the crankhousings pressure (since there is water to move..)
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Old 08 November 2004, 15:47   #12
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Sounds like a timing problem

What I would do is swap the HT leads over and try again.

Sounds very much like its firing with the piston at the bottom rather than top.

If you want to check this out scientifically.

1. Remove the plugs

2. Turn the engine over very slowly with a Top Dead Centre guage - (Blunt Screwdriver down the plug ole to you and me). Make a mark on the flywheel corresponding to TDC of each cylinder.

3. Turn the engine over slowly and see at which mark on the flywheel the plugs spark. If its not corresponding to the way you’ve got the ht leads connected now swap em over and try again.

Put your lucky gloves on just in case.

Cheers

Phil
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Old 08 November 2004, 16:04   #13
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its dark outside now... sounds like a good idea.. the manual says that the green/greenwhite = cylinder 1... and blue/bluewhite is cylinder 2... except i cant find ANYWHERE which is what.. and was just reading some posts on iboats forum some say top is 1, other say bottom is 1.. however it has worked this way round before somehow.. oh dear.. im getting confused now.. going to give it a try the other way round (with floodlight)

Ill be back!

*edit*:

Okay, swapped round.. same result but more often... left the plugs the same way round and took the top lead off, leaving bottom one with #2 coil, and even that makes it blow water out the exhaust 6ft into the air... ill try the TDC + spark thing... however there is nothing of the ignition to adjust.. except the carb..
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Old 08 November 2004, 17:14   #14
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The ignition is adjustable but we will leave that alone at the moment.

If you are sure that the coils, plug caps and low voltage wires are correct, then get pulling, a good half an hour will do you a power of good and soon start building mussles that you didn't know you had . You need to get that cleaner out and good fuel/oil back in and thats going to take time.

Suggest a few minutes with no plugs will make life easier.


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Old 08 November 2004, 17:36   #15
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its really really easy to pull when the plugs are removed, but with the plugs in there is sooo much compression (almost looks like its going hydraulic)
This is a stator thing with electronic switch box, has no points on it that can be adjusted.. ill move the thing back into the shed and work on it with lights..

Coils are brand new, spark looks great, they are permagaps, new leads, the wires appear to be fine (as they both spark)

i shall yank the cord till my arm falls off.. if i can manage to get myself to the shed... im feeling lazy tonight

If i were to take it to bits (the powerhead) what would i need to replace? the water jacket + cylinder head gaskit? (i've never had an outboard to bits.. have had car, lawnmower to bits, chainsaw / strimmer to bits..

i have the manual so i guess that's fine..

bleh.. lets get this thing working
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Old 08 November 2004, 18:24   #16
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Quote:
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there is sooo much compression
yus. dem 20ph mowters arr myty beests. tri taikin de fkker owt ov geer
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Old 08 November 2004, 19:33   #17
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arr, i'd try tha yeah, bah it aint in gear to start of wid.

Just did about 10 min pull, decided to take the carb off and all needles are fine so are the gaskets.... so i gave it another 2 min pull and sprayed petrol down the air intake of the carb and some back up the cylinder.. which resulted in the garage floor flooding with petrol through the exhaust...

Tried the TDC thing, TDC on the flywheel lined up with the cover mark is the lower one at TDC... and the cover says its piston 1... so it must be cylinder 1.. meaning the wiring was alright...
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Old 08 November 2004, 19:41   #18
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If all else fails, try poking it with a stick......
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Old 08 November 2004, 20:14   #19
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This doesn't help at all, but:

I had a 1978 Evinrude which had the same problem - really stiff to turn over. Never did work out wat it was.

That's enough words of wisdom from me for one thread!
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Old 08 November 2004, 20:23   #20
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Ok. So you have a good spark and the wiring is to the best of your knowledge the right way round. This points the problem at the fuel side.

Assuming you now have nice fresh fuel running through and all the nasty cleaner is out, you need to ensure fuel is getting to the plugs. You will need to pull it over (without spraying fuel into carb or down plug holes) a couple of times as if you are going to start it. Remove the plugs and see if they are wet with fuel. If not then you need to check the jets are clear, the float chamber is actually filling and the throttle isn't stuck open. If they are soaking then you will need to check to make sure the mixture is ok (maybe not use choke) and that the float chamber isn't overflowing (check float height).
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