Anyone here ever overhauled a 78' evinrude 140 V-4?

[BayouBlazer88]

Anyone here ever overhauled a 78\' evinrude 140 V-4?

just curious to see how difficult it was. I'll be tackling this over summer so that I'll hopefully get to ski on my boat by July. Also, about how much does the whole thing cost (machining work and new pistons, rings, etc) ? THanks.

 

[joez]

Re: Anyone here ever overhauled a 78\' evinrude 140 V-4?

dont remember the cost, but we revamped both our '60 75hp V4 and our 91 115hp V4, and they were the exact same process. Pretty simple to do, no real special tricks. I wish i had been older when we did it so i could give you a ballpark cost, but i cant remember. All i remember is the '91 went quick, it was the same thing over again.

 

[Thunder]

Re: Anyone here ever overhauled a 78\' evinrude 140 V-4?

You can also just buy a rebuilt powerhead. Its a lot easier and,like car engines it usually costs about the same as rebuilding it yourself(if you do a complete rebuild).They cost usually between 1600 to 2000.
Do a search on "Rebuilt outboard Powerheads" there are a lot of companies that do it.
http://www.outboardbore.comis one I can think of off the top of my head.

I dont know how bad of shape your powerhead is but most of the time if the crank/rod bearings aren't worn all you need to do is get the bore freshend up and new pistons/rings.
Get a good manual before you start and read it! Check clearances ect and see what you need to do. . Its not really that hard. All they are is a big 2 stroke.

 

[BayouBlazer88]

Re: Anyone here ever overhauled a 78\' evinrude 140 V-4?

1600 to 2000 for a rebuilt powerhead? Geez, I don't even have close to that kind of money. I was thinking if I rebuilt it myself it would be around 500 max. And yes I have a complete teardown manual that I've skimmed through a little so far. Also, where would you buy a rebuild kit (new pistons, rings, etc.) for this kind of motor? Is the only place to get them at my local evinrude/johnson dealership or is there other places out there that sell them?
Here's a little info about the motor. My aunt and uncle bought this thing new in 1978 and would go skiing with it maybe twice a year. The thing just sat in a garage most of the time. Another uncle of mine bought it from them about 8 years ago and used it a few times and then sold it to me because he wanted a fishing boat. So basically, this thing has hardly ever been used, probably not even 100 hours on this thing. This past summer a friend of mine wanted to take it to a lake about 3 hrs north from here and wanted to take it to the local evinrude shop to get a tune-up. The guys at the shop ran a compression test and said that one of the cylinders was at about half of what the others were and said that the motor needed to be overhauled at a cost of around 2300. Of course I said "Hell NO!" and brought the boat back to my shed where it's been sitting ever since, especially since I only payed 800 for it. Now I don't know much about outboard rebuilds, but I know the automotive machine shop that I used this summer charges about 400 for all the machine work for a SBC (boring and honing, polishing/grinding crank, setting cam bearings, etc.) so I'd imagine that it would be much cheaper for a smaller engine with less pistons but then again I know very little about big 2-stroke outboards so I'm not sure.

 

[Thunder]

Re: Anyone here ever overhauled a 78\' evinrude 140 V-4?

I doubdt if the thing needs a rebuild with as little use as you say. Unless someone didn't use 2 stroke oil in the gas or it overheated and seized.
If you only have one bad hole my first thought is Blown Head gasket. Its pretty common for older OBs to blow them espically if they sit around a long time. Pull the heads and check things out. It is a simple job. Head gaskets are cheap. usually under 30.00 for both sides. If it needs a rebuild the cylinders will be pretty scored. Espically around the intake and exhaust ports. If things look good, put in new head gaskets and go. /forums/images/graemlins/thumb.gif
If you do need a piston kit. They dont cost all that much either.

I buy marine parts from these guys they have pretty good prices.
www.basicpower.com/

 

[BayouBlazer88]

Re: Anyone here ever overhauled a 78\' evinrude 140 V-4?

Thanks. I won't be able to pull it apart at least for another month but I'll definitely keep that in mind when I do. Sure would be nice to get around having the block mahcined and buying new pistons. Also, would it be wise to replace the piston rings when I put it back together? I'll probably rebuild the carbureutor as well. Anything else I should inspect or look out for while I'm taking it apart? Also, how heavy is a V-4 power head? I don't have an engine lift or anything like that so is it possible to just pick it up by hand?

 

[Thunder]

Re: Anyone here ever overhauled a 78\' evinrude 140 V-4?

Should be able to pull off the powerhead without a lift. They are aluiminum so they dont weigh that much. Espically if you pull the heads, starter and flywheel first.
I would definatly check the head gaskets first before pulling it. I strongly suspect the boat shop that gave you the repair diagnosis was trying to make a few bucks.
Once you have the heads off it will be ovious if you need a rebuild. Outboard motors are built to last a long time with proper care. Unless there was a mechanical/maintience failure as I said in eariler post it should not need rings or pistons with the low hours it has on it.
A very common thing to have happen is; Someone buys an older boat and uses it for fishing. They dont replace the water pump.They Take out the boat and troll with it. The bad water pump cant pick up water at slow speeds. The engine gets hot overheats and blows the head gasket(s). Person thinks the engine is bad and sells the boat.
Be sure to replace the water punp in the lower unit. The impeller is made out of rubber. They wear out pretty fast and deteriate when setting around for a long time. I usually replace mine anually before every season.
Also service the lower unit. Change the lube ect