Evinrude 60hp 1986 siezed

stairliftoheaven

Petty Officer 2nd Class
Joined
Jun 8, 2004
Messages
113
hi to all: I'm about to take apart my 60hp twin after a sieze. I need to take the head off to have a look inside. couple fo questions: can I get the head off withoout removing the powerhead from the engine? and is it wise to let the torque off the head bolts sequentially? incidentally, managed to unsieze engine back on dry land but found zilch compression on the top cylinder when putting my thumb over the spark plug hole. <br /><br />have been reading these excellent threads and greatly value any advice given thaks; chris
 

stairliftoheaven

Petty Officer 2nd Class
Joined
Jun 8, 2004
Messages
113
Re: Evinrude 60hp 1986 siezed

got the head off: oh gawd!<br />seems like i had a melt down in the top cylinder and a shattered ring. took photos but can't seem to paste em in ere. heads trashed too. anyone know where I can get a replacement head in the UK? Lower bore in perfect condition though; no ridge at top of bore and no scrapes at all. Lower piston crown only has the word 'up' stamped on it so can I assume it is original and un-rebored? in which case i should be ok to bore out to .020? waithing for me manual to arrive from amazon antoher week to go....regards to all
 

stairliftoheaven

Petty Officer 2nd Class
Joined
Jun 8, 2004
Messages
113
Re: Evinrude 60hp 1986 siezed

jut=st a thought; is it possible to weld and skim a head, otherwise its a new head, advice pleeeeese
 

CorB

Petty Officer 3rd Class
Joined
Aug 6, 2003
Messages
76
Re: Evinrude 60hp 1986 siezed

Stairliftoheaven,<br /><br />You can't assume it isn't overbored because it says the word "UP". It describes the way the piston should be mounted in the cylinder. So I guess you should have it measured (both cylinders), and then you'll know for sure which oversize you need. And how your other cylinder is.<br />Pistons are very expensive (especially in Europe) Original pistons for my '78 55 HP Johnson were 310,00 Euro over here in the Netherlands. I used Wiseco's and they were around 130,00 Euro, and they say they are better pistons too.<br />You need a machine shop to measure, rebore and hone the cylinder and they need the new piston to do that accurately.<br />It is wise to find a machine shop who has experience with 2-stroke and/or outboards because it has some specialties like the ports which could make honing difficult, some port chamfering after reboring. And also the different materials (aluminium-like/steel-like) used for the casting and cylinder walls need extra attention in the reboring process, because the materials react differently on heat (the exact description can be found in a thread about reboring tolerances I responded to a while ago).<br /><br />While you have your powerhead apart you better thorougly check the bearings, crankshaft bearing journals and connecting rod bearing journals (look for rust and pittings on the driveways, caused by possible former submersion or not winterising properly). But I'm sure your manual points out ALL the steps of checking and treating the parts. There's lots of more to check if you want the job to be done right. (a job worth doing is a job worth doing right).<br /><br />If you need bearings etc.. you might take a look at parts from Sierra, because original parts are expensive as I mentioned before.<br /><br />Be sure to have the right equipment for measuring or otherwise ask a specialist/machine shop to do it for you.<br /><br />I don't know if your head can be welded and skimmed. Can't you find someone who sells used parts near you? Heads don't get ruined that often, so you have a great chance finding a good used one, and then have it skimmed anyway. And maybe the head isn't that bad? Some pitting is Ok as far as I know, but someone experienced could check it for you.<br /><br />After you rebuilt it, be sure you find the cause of the burning piston. The damage you have is propably a result of a different cause (lean running? ignition timing? overheating?).<br /><br />One last word of advice is to work thorougly and don't get in a hurry, while rebuilding a powerhead. There are lots of things to consider and to check (there's more then what I mentioned) And a mistake is very easily made. And spending all the money again on a gasket kit and possibly more isn't really fun. But when it's finished and when it runs great you're very happy and proud!<br /><br />I'm not a specialist in this area, but I was in the same process a while ago as you are in now.<br /><br />Good luck
 
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