Something Broke During Impeller Change 73 Evinrude 25hp

[cajuncook1]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

carpking, PM me your email address. I can send something that will help.

 

[AlTn]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

k...well, it's a 1972 model I have and it looks like 1973 is the first year they went to the larger block for the 25 hp. as the block and head part no's are different although the powerhead to exhaust housing gasket no's are the same...hard to tell exactly from your pics, but if it's necessary to reposition your pan to gain access it's held in place by those 4 bolts through the rubber mounts...you may to detach the vertical shaft and shift mech. as well to get sufficent space to get on that front screw...that's the base of the powerhead that screw is coming through, you won't need to fool with the intake at this point

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

k...well, it's a 1972 model I have and it looks like 1973 is the first year they went to the larger block for the 25 hp. as the block and head part no's are different although the powerhead to exhaust housing gasket no's are the same...hard to tell exactly from your pics, but if it's necessary to reposition your pan to gain access it's held in place by those 4 bolts through the rubber mounts...you may to detach the vertical shaft and shift mech. as well to get sufficent space to get on that front screw...that's the base of the powerhead that screw is coming through, you won't need to fool with the intake at this point

The more I look at it, the more it looks I like should be able to remove the pan and power head and exhaust housing away from the steering part of the out board. My shift linkage is contained in exhaust housing. If I can do this, the part of the "handle pan" (sorry don't know technical term), motor mounts and steering shaft would remain on motor stand while the rest pulled away. I see two large bolts coming off mounts the grab lower cover and two screws going from steering shaft into exhaust housing. Seems too easy though.

 

[cajuncook1]

Re: Something Broke During Impeller Change 73 Evinrude 25hp









I have a 1970 18hp Evinrude and I don't see what you are talking about regarding a carbon seal??

When you pull down the lower unit: (1st diagram)

- drive shaft
- shift rod
- impeller housing
- on top of the impeller housing is the exhaust spacer housing (part 114 ) with the upper and lower spacer o-rings (parts 113 and 115)
- the gearcase housing and all its contents.

Is it possible the the upper oring came off the exhaust spacer housing??

Please supply a picture of the your lower unit with all its components as listed above.




The carbon seal that I think that your are describing is a combination of parts that form lower crank case seal.

Parts 20 thru 28. Part #24 being the carbon seal.






Yall think that fell from above???

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

Update: Through trial and error, I have discovered if I tilt motor all the way up as AlTn suggested, I can take a stout screw driver and pry the rubber motor mounts enough to get a socket on the last bolt. Didn't go ahead with it tonight as I'm going to get an extra hand to help me to keep from breaking anything. So, hopefully I'll have it removed tomorrow. Going to order the new seal and o rings tomorrow as well. May need help as to how they go back in as the old one is trash so there is no reversing procedure. Still need suggestions on flywheel removal as well...as I mentioned a few posts above this one. Really appreciate all the help!! Great forum!!

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

Hey cajun, you are correct. It is the carbon seal that that is part of the lower crank case seal. It didn't fall out. It shattered into bits as I was tapping lower unit down to change impeller. The bits came out in 1/4" chunks. Now, I assume it broke as I was doing this. It could have already been busted before I started, and the pieces fell out in the process. Don't really know how I would know for sure when the seal received the damage. There is alot of oil residue throughout exhaust housing, but the shaft the drive shaft slides up to meat lower crank area is clean as a pin. Doesn't appear to be any evidence of oil escaping there. Great diagrams though. Those will come in very handy on re-assembly. Question: will I be o.k. just ordering the replacement seal and o-rings? I really don't want to have to buy another roller bearing...

P.S. The lower unit is fine. No damage to it all.

 

[cajuncook1]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

Here are the instructions verbatim.

You should not have remove the flywheel or the starter brackets.

- Carburetor yes

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

Not removing flywheel because of this. I'm going to replace points and condensors later. Thanks for the manual instructions. Although, I'm not going to have to remove carb for powerhead removal. Just the linkages. As well as fuel line from pump, throttle linkage and shifter lever. I am also ordering a carb kit though for later. I've never rebuilt one. Hope I don't mess it up too.

 

[AlTn]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

as they say,"we'll know more upon disassembly.", which is right before, " we've run into more than we expected." and then it's " how much do you want to spend on this?"..j/k <sorta>..hopefully you'll just need to order an exhaust housing to powerhead gasket along with the carbon seal and oring

something to think about at this stage...it's a great time to replace the exhaust cover gaskets, inner and outer, as you can look for any piston scuffing or ring binding in the exhaust ports area as well..clean out the carbon from there too

head gasket replacement and head surfacing too if the cylinder bores and piston tops check out

just mentioning these as you're there and they are easier to get to now...you may see something that makes you decide you don't want to spend any more..or the reverse may be true

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

O.k...finally got powerhead off. As expected, carbon seal completely missing. I'm including some pics as well as a few other questions. The first pic is the bottom of the crank unchanged on removal. The snap ring is in place as well as the spring. Second pic shows the loose pieces found in exhaust housing. O-ring is self explanatory, a metal ring with a notch, and a plastic washer with a raised lip on the I.D.. Third pic shows the washer in comparison to the hole in crank for drive shaft. I cannot understand where this washer must've been. The I.D. is way too small for drive shaft to fit through and the O.D. is too big to go inside crank hole. I thought maybe it was what the drive shaft rested against inside crank. And that would be my question. How does this stuff go back together? The diagrams I've looked at don't really tell me much.

http://i296.photobucket.com/albums/mm167/djsteele95/IMAG1084.jpg?t=1365216404

http://i296.photobucket.com/albums/mm167/djsteele95/IMAG1085.jpg?t=1365216496

http://i296.photobucket.com/albums/mm167/djsteele95/IMAG1086.jpg?t=1365216609

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

The thing is, looking at parts diagram, the small plastic washer and the metal ring don't exist. The only parts that are not on crank are #23, small O-ring, which I actually believe is the small o-ring at the top of drive shaft. Large o-ring, #22 which I pictured earlier, and I believe fits inside carbon seal. And #24, the carbon seal itself. 25, 26 27, and 28 are all still on crank and appear to be in good shape.

http://i296.photobucket.com/albums/mm167/djsteele95/40194.gif?t=1365219309

 

[AlTn]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

the plastic washer and metal ring weren't present on the '72 25 hp. powerhead I removed

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

the plastic washer and metal ring weren't present on the '72 25 hp. powerhead I removed

That's good to know. I can't see any place or use for them. I'm assuming possibly some other work was done on motor in the past and they fell into shaft tube. Could be what caused damage to carbon seal in the first place.

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

I am just now getting around to putting this thing back together....really busy at work and home. Anyway, I received the carbon seal, large o-ring and small o-ring. Now, I can't seem to figure out the order it all goes back together. I have looked at the diagram and my confusion is with the small o-ring. Is it supposed to rest under (power head upside down) the carbon seal or does it fit inside the I.D. of the seal itself? Inside seems to make more sense, but the diagram doesn't specify. Small o-ring is #23 on diagram. Itis biiger than appears though. It will fit I.D of carbon seal perfectly. Hoping AlTn can help with this as he has made a similar repair. However, any help would be appreciated.

http://i296.photobucket.com/albums/mm167/djsteele95/40194.gif

 

[glenn property of pam]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

never worked on your motor but i have installed a few carbon seals at work

The face the carbon seal runs against is normally stationary and has a seal around the outside as it does not move this is the bearing housing i believe from the drawing part 21 with the seal 22 on the outside. the carbon seal goes on the rotating part (crank) and has a seal on the inside so 23 goes inside 24 lube the seal so it will slide on the shaft and make sure the seal face (the flat side with no cut outs) faces the bearing housing. 25 goes on with cup down and then the spring 26 goes into the cup then 27 goes at the bottom of the spring and you compresses the spring and put 28 the retaining ring on. the spring holds the carbon against the polished face of the bearing holder the carbon turns with the crank while the bearing housing stays put making a seal.

from your pictures i think part 27 is the ring you found but from what im seeing in the pictures the face the carbon runs against should be flat yours has bearing numbers so maybe im wrong unless some one rebuilt the motor and put the bearing in backwards (unless theres a raised piece on the bearing housing inside the spring with the pic its hard to tell). the carbon must go against a smooth machined surface if its scratched up it has to be replaced. scale is hard to tell on pics so i have no idea where the carbon will contact the bearing housing so a few pics when the parts are removed will help.

the plastic piece maybe a guide to help the shaft engage the crank depending on its size

hope this helps

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

O.k.. Here are some more pics. First is crank hole with parts removed. It's hard to tell, but there is a smooth machined surface directly around crank which is just slightly raised from area with engraved lettering. Other pics are of both sides of carbon seal with o-ring inserted into I.D.. One side is flat, which is the side with the two pin holes. The other side has a lip around I.D.. I don't have, and apparently it wasn't ever there, is the washer that goes between carbon seal and spring. One pic shows all parts I have. The large o-ring appears to fit main hole. Carbon seal will fit inside into it if slightly forced. I'm guessing this is what makes a tight fit. One thing I don't understand here, and may sound very dumb, but what exactly am I sealing here? Is it to keep something out or to keep something in? It reminds me of a throwout bearing on a clutch with the spring and rotating seal. Sorry about low quality of pics. Phone flash whited everything out and flashlight didnt provide enough... Oh...and I have part 27. It is part 25 that appears to be gone.

http://i296.photobucket.com/albums/mm167/djsteele95/IMAG1111.jpg?t=1366508199

http://i296.photobucket.com/albums/mm167/djsteele95/IMAG1113.jpg?t=1366508165

http://i296.photobucket.com/albums/mm167/djsteele95/IMAG1112.jpg?t=1366508152

http://i296.photobucket.com/albums/mm167/djsteele95/IMAG1115.jpg?t=1366508177

http://i296.photobucket.com/albums/mm167/djsteele95/IMAG1117.jpg?t=1366508129

 

[glenn property of pam]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

you are sealing the crank case so when it pulls vacuum the air comes from the carbs not from the inside of the leg. After looking at the pics that makes sense the carbon has a raised lip (not the side with the holes) that will ride against the raised piece on the bearing housing which is scratched but may be ok. the large o-ring is for the bearing housing to crank case to stop vacuum escaping down the sides of the bearing housing so you wont need that. The small o-ring is to stop vacuum loss between the crank and the carbon. When two perfectly flat surfaces ride against each other they create a seal. The spring assembly is to keep the carbon on the bearing housing at low pressure as the crank moves a tiny bit the spring moves so the carbon is not crushed or loose. The part you now need is the ring you found in the beginning and looks damadged #27 that goes between the spring and carbon

when you get the piece remember to lube the o-ring in the carbon as that will be sliding up and down and if the o-ring gets stuck the carbon will break. Also check the crank for side to side movement while you can to ensure the bearing is good

 

[carpking]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

Actually, number 27 was between retaining clip and smaller end of spring. I believe I need 25 which is the large side of spring that fits against carbon seal. @4 is the carbon seal itself. So, the lipped side of carbon seal goes against smooth machined surface and not the other way around? I was going to purchase another 27 as well but iboats apparently doesnt carry it and marine engine.com wants $19.00 for a washer. Is there something else I could use in it's place?

 

[glenn property of pam]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

you are right its part 25 you need. your part 27 looks ok in pics its only to keep the spring from walking off the clip.

the carbon has 2 holes and a slot on one side that are drain holes thats the side that the spring goes.

remove the o-ring from the carbon and gently lower it and you should see how the cabon touches the bearing housing creating a seal

 

[AlTn]

Re: Something Broke During Impeller Change 73 Evinrude 25hp

just as glenn says..smooth side against the bearing...the larger thin oring is internal to the crankcase...you might p/u #25 cheap at one of the salvage places listed in the Top Secret Files