1969 6HP Impeller replacement

[daveh77]

Just acquired another vintage Evinrude, 6HP, 6903M-E01331, 10 years newer than my 1959 5.5HP Golden Jubilee.
Hoping that is 10 years of progress. Definitely lighter and more compact. Looks easier to work on too.
I know on the 1959 model, I have to pull the powerhead to replace the impeller.
Is this 1969 the same procedure?
The rope starter column setup is definitely an improvement.

Are there any other notable differences or improvements from 1959 to 1969?

Any particular weaknesses on this '69 that I should be aware of while bringing it back to life?

Seems to have real good compression. Everything turns, F & R.
The only red flag I see is the thermostat gasket is partially blown out of place.

PO said it came on a sailboat he inherited 6 years ago. Said it ran before he got it, but never got his boat in the water. He also said it was a 1985, but coming from a distant relative a long ways off, probably an honest mistake.

Thanks, Dave

 

[racerone]

No need to remove powerhead to change impeller.-----But there are some steps that need to be followed to get the powerhead seal pin to come through a slot.------The 69 model has needle bearings on big end of the rods.-----Thermostats are often missing or stuck open.

 

[F_R]

Yep, to remove lower unit, the shift rod disconnect is in the gap formed when you remove the bolts and drop the lower unit down about 3/4". More or less at the same time, the pin has to be positioned to come down through a slot. To do that, remove the spark plugs, then gently pull the lower unit down while rotating the flywheel. When the pin/slot aligns STOP turning the flywheel and don't turn it again till the lower unit is reinstalled back in place. When the lower unit is down and out, notice the position of the pin. Put it back in the same position for reassembly and if the flywheel hasn't been disturbed, all should slide together easily.

 

[daveh77]

Thank you both, exactly what I needed to know.
Forgive my novice ignorance but I'm not completely up to speed with all the OB terminology.
The Evinrude parts diagram shows the "Lower Unit Group" as the entire column below the handle and powerhead base gasket. No sign of a long shift shaft or any long vertical shaft in that blow up view.

Then the diagram for the "Gearcase Group" is the bottom gear housing and the lower column part with the anti-cav plate, plus 5" extension if included.
The longest shaft appears to be the main drive shaft running through the water pump to the bottom pinion gear.
I assume the shorter, lighter shaft close to the prop is the shift shaft.
Also shows a shorter little shaft near the prop.

I have these marginal clarity diagrams but no parts list to say what each part number is. They show the part ok but not exactly how they fit together.

I do recall seeing various OB Gearcase units with long shaft or shafts extending exposed, like for sale on on Craigs List. Usually these are called "Lower Units".

Assuming they pull down out of the vertical housing, connecting up near the powerhead?
So the trick is to disconnect that upper coupler link up top so shafts come out with the gearcase?

Where exactly does it come apart to expose that shift shaft coupler?

Also, I see what looks like pins in the driveshaft, the lower one must be the impeller pin, the other is up top. Is that the one I need to keep lined up?

Does anyone have a link or PDF parts number list to go with these factory diagrams?

I have wrenched on everything from chainsaws & dirt bikes to muscle cars and diesels but outboards are a new venture.

Thanks for your help, Dave

 

[hardwater fisherman]

unbolt the gearcase and it should drop down enough to reveal the coupler. remove one of the screws and loosen the other one. The gearcase should now come off. As the others said do not forget about the pin near the top of the driveshaft.

 

[Vic.S]

The terminology is a bit confusing .... and variable .... it has changed over time so newer pats lists are divided up differently to older ones. They are different between different manufacturers.

You will find the official BRP parts diagrams and parts lists at http://epc.brp.com/Index.aspx?lang=E&s1=38e52324-7928-4513-b428-dcffaf59df66
The "Shop" tab on this site will also take you to the same diagrams and Iboats parts lists for OMC and other brands . ( I find iBoats parts lists a little user unfriendly)

Usually the parts for the long shaft versions are listed together with the standard parts but for your engine they appear at the end of the list.( at least in the BRP list)
You just have to learn to find your way.

ITYWF that the lower shift rod is listed with the gearcase parts while the upper shift rods ( standard and long) are listed under "lower unit"
Some engines have a rubber plug in the side of the exhaust housing ( aka "the leg") to access the coupling between upper and lower shift rods
Some require the gear case to be dropped slightly to access the coupling ( yours is like this)
there are other arrangements too
My '84 6hp has no join in the shift rod

In your engine the lower pin is the impeller drive pin ( but not all are driven by a pin through the shaft ... mine isn't) The upper pin supports all the components of the seal assembly at the top. It has to be correctly aligned to come through a slot when removing the gear case assembly. Not all are like this.

You need a workshop manual.
While you can always get help from forums like this one you cannot expect them to be a free substitute for a manual.

The Official manuals available exclusively from Outboardbooks.com are by far the best but other published by the likes of Seloc are more generally available

 

[daveh77]

Hardwater and Vic,
Thanks, you helped clear up some foggy spots. The parts lists with the diagrams are a big help. Defintely want a factory service manual, was hesitant to get a seloc or similar. I have always hated Chiltons and other non oem manuals, always inadequate so wasn't sure how good seloc would be.
Thanks for the link to a real manual.
What seals or gaskets would be wise to replace while I have it apart?
Anything else up top besides the new thermostat cover gasket?
Why are so many of these found with the stat stuck open or missing? Overheating problems or what?
Thanks again to everyone who has answered here.
Dave

 

[racerone]

The thermostat normally fails in the open position.------Missing because folks simply do not know how important that part is.-----And a very common thermostat that was used for many years from about 1960 to 1998 in some motors.

 

[Crosbyman]

fyi I just ordered 3 thermostats from EBAY for 10$ CND ..about $7 U$ a piece
with free shipping. from seller VKI_GO

my lower price bid was accepted I offered 10$ CDN for 3 instead of $13.00 each

don't forget the rim gaskets !!