How do you replace crank seals?

[470mercruiser]

Im working on a kawasaki 650 and I want to replace the crank seals. How do you replace the seals on the side with the drive coupler on it? How do i seperate the drive coupler from the crank? Also how would i replace those bearings in between the crank halves? Is there a way to seperate the crank?

 

[Jeff Walkowiak]

Re: How do you replace crank seals?

the correct way is to pull the engine strip it so you can split the case, pull the cylinders off, pull the wrist pins and remove the pistons then take out the crank and send it to some place like s b t for a rebuilt crank with new bearings seals etc,, do it yourself, I doubt it because it's a pressed crank and the timing of the parts would be critical, plus sbt welds the crank so it won't get out of time, if you are just doing the end bearings and seals you may be ok doing that yourself as long as the other bearings are in good shape ,if not you wasted your time.
the dampener unscrews off the back of the crank . need a special tool that locks in to the holes plus you need to secure the crank so it won't turn as you unscrew the piece.

 

[470mercruiser]

Re: How do you replace crank seals?

ok so i wont be doing the inside bearings. How can i tell if they are bad? I really just want to replace the seals. I have the engine apart and i really dont want to put it back together without replacing those seals. where do i get one of the tools to take of the drive coupler?

 

[Jeff Walkowiak]

Re: How do you replace crank seals?

I spin the bearings if they make noise I replace them,, they should spin smooth and quiet. see if your local Kawasaki dealer sells the tool,, I made my own. I used a big pair of vice grips and welded pegs in them to catch the 2 holes in the part so I could remove it.

 

[470mercruiser]

Re: How do you replace crank seals?

i dont see anywhere near the coupler for any kind of tool holes. I have 2 stroke oil on the bearings right now should i clean them off with brake cleaner to check them? They turn kinda hard right now due to the oil on them. I have klotz oil on them. They turn without noise but i think i should check them clean. Can i use brake cleaner to clean them or should i use something else?

 

[Jeff Walkowiak]

Re: How do you replace crank seals?

they should spin easily with the oil on them,, and be careful removing the surface oil on any internal parts they will rust so fast you won't believe it.
try spraying them with some wd40 and see if they turn easily, as for the coupler there should be 2 opposing holes just behind the part with the fingers

 

[470mercruiser]

Re: How do you replace crank seals?

Ok I just think that oil i have is really sticky. Ill clean it off then hose it down with wd40. Then spin them. I have looked and i can find no holes. i can take pictures if you like. which way do i turn it? It would have opposite threads right? And that engine runs clockwise as viewed from behind right?

 

[Jeff Walkowiak]

Re: How do you replace crank seals?

is there room for a pipe wrench when all else fails those usually work, don't remember the thread direction, yamaha is left and sea doo is right not sure of the kaw been many years since I messed with those.

 

[470mercruiser]

Re: How do you replace crank seals?

there might be enough room but i dont want to screw up the seal surface. It seems to me sea doo is always opposite of everything else so ill try to the left.

 

[470mercruiser]

Re: How do you replace crank seals?

Ok im back to putting this engine back together. I got the coupler off and i got a full gasket set with seals. now my question is. I noticed some grease on the inner seal near the coupler. should i put this grease in the new seal? what kind of grease is this? Please help asap. Jeff i hope your reading this. thanks.

 

[470mercruiser]

Re: How do you replace crank seals?

ok forget the last question. I just used the grease that was in the old seal.

However i do have a more important question. Is there a certain way the head gasket is suppose to go on? there are no marking like the old gasket but i tried to line up the coolant holes the best i could. Is there a way to tell if its in right? I put the raised part that goes around the cylinder bores up. Is that going to be ok. Please let me know. Thanks.

 

[JUSTINTIME]

Re: How do you replace crank seals?

yes raised part up

 

[Jeff Walkowiak]

Re: How do you replace crank seals?

probably too late,, but it is very important that you resurface the head before you put the engine back together,, those heads warp . you use some spray contact glue on a piece of thick glass and glue on some 80 grit sand paper then slide the head across this in a circular motion , at first you will see the warping because some of the head will be clean and the other part will still be dark,, you keep doing this till it is all clean with no more dark spots.
I actually built a simple and effective machine for surfacing parts .
I used a spindle a wheel and a motor to drive it, doing it on a piece of glass is a slow process but you are only doing one head,, I do a lot of parts and since I'm lazy but inovative, I made this to get-r-done in short order..

 

[470mercruiser]

Re: How do you replace crank seals?

would the head warp in like 30 hours? This engine was rebuilt proffesionally and the previous owner ran it about 30 hours then it wouldnt start. so he sold it to me. it sat for a little while it had water sitting in it and it rusted the starter bendix, flywheel and stator. so i pulled it apart to check it out for more damage. i would have done the resurfacing if there were more hours on it. i just didnt think it would be that bad with only 30 hours. let me know and thanks for the help.

 

[Jeff Walkowiak]

Re: How do you replace crank seals?

every time

 

[freddyray21]

Re: How do you replace crank seals?

Jeff wonder what my wife would say if I glued a piece of glass to her pottery wheel. Never mind bad idea messing with the wife's pottery wheel. but what an idea!

 

[Jeff Walkowiak]

Re: How do you replace crank seals?

pottery wheel would work , make a plywood base, use some liquid nails to glue on the glass to the plywood, make a rim around the wood that clamps on the side of the wheel and you're in business.. I sand blast the top surface of the glass to make the glue stick better and buy huge sanding belts , cut and paste them on the glass,, I also made my last one with removable disks that just drop on to the wheel with pegs made of steel tubing ,the wheel I use acts as a large pulley for belt drive off a 1/3 hp motor, I have to say it really makes short work of resurfacing parts.