1985 Evinrude 8hp - T

[beverly]

Picked up a boat (13 foot holy aluminum), motor (1982 Evinrude 8hp) and trailer (homemade 150 LBS busted lights).

Note.
First time on the water for 4 hours (fishing test). Mid throttle it would misfire but after it warmed up you could almost go WOT. At WOT the engine hesitates (kinda misfire marble/clattering/rattling/backfire? sound), unless you backed off the throttle a mm. And if you kept it there, it would run fine.

Metal shavings on engine caused by a metal pin (holding the/sliding/swivel the gear for the pull cord) hitting the flywheel when it started up and the pull cord was rewinding back the cord.

End of note...

Its running better than it did.. Thanks to all for your info input from other posts

Old spark plug were dry, light brown (use them for spares since they don't match what should be in there [gap was off too (close to 4)].. Replaced those.

Took the carb apart, bathed it in a sonic vibrator, and re-adjusted the float (no rebuild kit). All parts in decent shape. Only one metal shaving found after carb cleaning.
Cleaned the carb again with carb cleaner. Took the spark plugs off and sprayed carb cleaner in the cylinders. Did this 3 times.

Took a clear line from the fuel pump to carb and bubbles are getting in (replacing a new aftermarket fuel line hose from the tank to the outboard) getting an OEM one instead. I heard some horror story about these things (hit and miss). Fuel leak happens @ the female plug to male on the outboard. if you wiggle it you can get a steady connection, so it?s not seating properly.

Its making good compression. On cold, 1st pull 60 psi, 2nd pull 80 psi, 3rd pull 107 psi. Both cylinders were the same. I've heard guys that can only get up to 90 with new rings and head gasket but that?s a 40 50 HP evinrude.
When the engine is running for 30 min or more, the water is luke warn and engine isn't hot to touch (really warm). Makes me wonder is there even a thermostat in there, doing its job...

Next I?m going to is see if there?s play in the pistons which i doubt since it only makes the marble/chattering/ratting sound at WOT or kind of misfires but that might be due to the exhaust leak happening or something tapping with the manual pull starter which i heard it might be this.


To Do List I
- Check for piston play
- Re-replace fuel line from tank to outboard. (defective)
- Tight engine block to exhaust (60 ft lbs.?) don?t know how they go together but, I?ll find out soon enough
- Wash engine compartment (with MeanGreen)
- Make an air filter (like the ones for lawnmowers or a screen mesh) Still wonder if it had one.

To Do List II (for next year | maybe)
- New/rebuild propeller (current one has a crack and some dings
- Exhaust gasket (if it needs one)
- Thermostat (if it needs one)

Any Comments are Welcomed.

Maybe I've over looked something or haven't wrote about it.

 

[oldcatamount]

Re: 1982 Evinrude 8hp - T

Re: 1982 Evinrude 8hp - T

You're doing great, although, I wouldn't put any more carb cleaner into the cylinders. that's not a good idea. Run your motor with some Sea Foam mixed with the fuel/oil mixture. that will help take out the excess carbon build up and is very good for the motor. You have good compression so, don't worry about the rings or piston slop, you don't have any issue there.

 

[Daviet]

Re: 1982 Evinrude 8hp - T

Re: 1982 Evinrude 8hp - T

Looks pretty good.
You do not need any type of air filter, If you installed something it might throw the carb settings out of wack.
Why do you have to retorque the bolts holding the powerhead on to the exhaust housing?

 

[beverly]

Re: 1982 Evinrude 8hp - T

Re: 1982 Evinrude 8hp - T

............

Looks pretty good.
Why do you have to retorque the bolts holding the powerhead on to the exhaust housing?

Next I?m going to is see if there?s play in the pistons which i doubt since it only makes the marble/chattering/ratting sound at WOT or kind of misfires but that might be due to the exhaust leak happening or something tapping with the manual pull starter which i heard it might be this.

 

[Daviet]

Re: 1982 Evinrude 8hp - T

Re: 1982 Evinrude 8hp - T

Sorry, I didn't catch that. If you have an exhaust leak at the powerhead/exhaust housing joint, you will probably have to replace the gasket to cure the problem.

 

[beverly]

Re: 1982 Evinrude 8hp - T

Re: 1982 Evinrude 8hp - T

Might just need to be tightened up. (vibrated loose)

Daviet, Is it easy to change that gasket? take off the bolts from the bottom engine (thats hold it down) and lift up? I read other makes and model you have to drop the gearbox.

 

[Daviet]

Re: 1982 Evinrude 8hp - T

Re: 1982 Evinrude 8hp - T

I think you can replace the gasket without dropping the lower unit. The only problem I can see is aligning the splines in the crank with the drive shaft without moving the gasket. You could make some alignmemt pins and cure that problem.

 

[beverly]

Re: 1982 Evinrude 8hp - T

Re: 1982 Evinrude 8hp - T

....

 

[beverly]

Re: 1982 Evinrude 8hp - T

Re: 1982 Evinrude 8hp - T

Bolts 8 and 82 attach the exhaust housing to the engine.

The gasket is held by the exhaust pipe housing (around the crankshaft and water pipe) and motor mounts attached to the engine with two small bolts. The only thing I see holding down the exhaust housing [when I remove the engine] is the exhaust baffle (two bolts).

Drive shaft should come right out no problem. Unless theres a clip holding it up which i doubt.

Water tube (steel?? or plastic??). How does it attach to the engine.

Only thing to watch out for is the shift rod (may need adjustment, if it moves but checked anyways). That day comes when I install an impeller.

I might get away with tightening the engine down. or if not, a gasket is needed.

After this season.. I wanna go have fun and fish before its too cold and the river freezes up. Makes me wonder if Germany engineered the outboard but used SAE bolts.

 

[Vic.S]

Re: 1982 Evinrude 8hp - T

Re: 1982 Evinrude 8hp - T

This is pretty much the same as my 1984 6hp.
Actually I think you will find if it is a 1982 model that it is actually 7.5 hp. (8 hp models did not appear until 1984) The 7.5 models I think moreor less became the new 6 hp models in 1984 when the method of measuring HP changed!

The water tube ( it is copper) is held by its upper grommet and the spacer, #75 and #69, in a tapered hole in the innner exhaust tube.

If you remove the power head the water tube will pull out from the waterpump and come with it
I have not tried it but it may be difficult to relocate it in the water pump during reassembly .. a bit of a fiddle anyway.

The shift rod will cause you no problems as you will not even be accessing that in removing the power head. It is captive in the gearcase so it comes way with that. Just one of the items to line up .. a little bit of a fiddle but not difficult .. when refitting the gearcase. There is no adjustment necessary or possible.

The drive shaft should pull from the crankshaft provided it has not rusted in No clips or anything holding it.

To break the joint between the crankcase and the outer exhaust housing I found it necessary to rock the power-head fore and aft ... that will not be possible if the gearcase is still on as the drive shaft will prevent you rocking it.

If it were mine I would drop the gear case off first ( in fact that is what I have done twice) and take the opportunity to renew the pump impeller while it is off. Also the drive shaft seals .

Your compression figures look pretty good to me. Based on them I would be leaving pistons etc alone.

I would be more concerned about the state of the gears and the gearcase bearings if it has been run with water and no oil! ... not seawater I hope!. You'll be renewing the seals presumably.

The thermostat is easy enough to check .. it is also the pressure controlling valve for the cooling system.

 

[beverly]

Re: 1985 Evinrude 8hp - T

Its running a whole lot better, doesn't miss a beat.. (even at WOT).

Things I did..

- Check for piston play
= Cancelled

- Re-replace fuel line from tank to outboard. (defective)
= Done. Well worth the extra 20 bucks.

- Tight engine block to exhaust (60 ft lbs.?) don?t know how they go together but, I?ll find out soon enough.
= Cancelled

- Make an air filter (like the ones for lawnmowers or a screen mesh) Still wonder if it had one.
= Cancelled


Just by changing the after-market fuel line to an OEM one. The fuel/air leaks stopped, the motor ran like it should and never missed a beat. Started up on the first pull.

Down at the dealer he said, he usually see's that after-market fuel line again but never see's that OEM one again. I ask "Then why do you sell it?" he said "To get customers to come back." What a waste of gas to get there. (Located not even near a lake. in the city, south in Ottawa) Good thing for me, its on the way home from work.

Now that its running great. At WOT, I do wish the boat went faster. It beats paddling. I even opened up the throttle up with my finger (on carb) at WOT (extra play). Didn't make a difference.


I was told wrong again.
Its an 1985 Evinrude 8hp. (changed topic. thanks Vic.S for the heads up on the year)




ToDo List I
- Clean Engine compartment.
- SeaFoam

ToDo List II (for next year)
- New/rebuild propeller (current one has a crack and some dings)

 

[raczekp1]

Re: 1985 Evinrude 8hp - T

after one fishing trip i would check colour of gearcase oil.
to be sure there is no water leak into gearcase

 

[beverly]

Re: 1985 Evinrude 8hp - T

Use to be clear as water. After the first ride, it got this color.

You can also see that color coming out of the prop shaft a bit.

 

[Vic.S]

Re: 1985 Evinrude 8hp - T

Use to be clear as water. After the first ride, it got this color.

If thats the gear case oil after one trip then you need to be seriously looking at the gearcase seals and I would think the gasket between the gearcase and the cover.
It looks as though there is not only water in there but carbon from the exhaust!

The oil should be as clear as the day it was put in there. Perhaps after a seasons use just a little darker in colour.

 

[beverly]

Re: 1985 Evinrude 8hp - T

I didn't get to take picture's (forgot camera) but, where does the drive shaft O-ring (on top of the water pump) go (#55)? Its too small (It'll be tight) to fit on the drive shaft and there wasn't one there to begin with.

#22 calls for two O-ring on the shift rod but only one fits and the picture only shows one.

 

[bktheking]

Re: 1985 Evinrude 8hp - T

but never see's that OEM one again. I ask "Then why do you sell it?" he said "To get customers to come back." What a waste of gas to get there. (Located not even near a lake. in the city, south in Ottawa) Good thing for me, its on the way home from work.

Alfred knows better than that! That oring should be tight, you don't want it loose or the pump will have issues providing good pressure.

 

[beverly]

Re: 1985 Evinrude 8hp - T

Already provides good water pressure.

That Drive Shaft O-Ring (#55) should go

1. Inside top of the water pump? (in groves, really tight)

2. On the outside, top of the water pump?

Or
3. On top, drive shaft to crankcase?

 

[bktheking]

Re: 1985 Evinrude 8hp - T

Never done an 8 but the 9.9's have a larger o ring that sits on top of the housing to provided a positive seal against the exhaust housing, I'm sure Vic would know.

 

[Vic.S]

Re: 1985 Evinrude 8hp - T

I must admit that I am puzzled by that O ring #55.

Usually we are told that it fits at the top of the drive shaft immediately below the splines to prevent ingress of water etc that could lead to these becoming rusted into the crankshaft.

I have no recollection of there being an O ring in that position in my '84 6hp.

1985, and later models, have double seals built into the inner exhaust tube that perform that job and I don't think you would be able to fit an O ring at the top of the shaft because of them.
I actually fitted a new inner exhaust tube which had the two seals because i could not get the correct one at the time. I had to cut off one of the seals but the remaining one effectively seals the splines safely out of harms way. It was a "modification" forced on me that seem to have a significant benefit. I would not have been able , I dont think, to fit an O ring at the top even if there had been one originally.

I believe that the O ring may fit in a groove in the top of the water pump to make a seal there with the driveshaft. I have not investigated this as a possibility. Next time I replace the pump impeller ... possibly this winter although it is pumping well at present ... I will investigate further.

I cannot see that just sitting around the shaft on top of the pump housing will serve any useful purpose as there is nothing to keep it in place.

I would look very closely at the waterpump housing to see if there is an O ring tucked away in there.

I could be hopelessly wrong about all of this :redface: