Coolant Loss

[Jakobi]

I had wondered about such things. A bigger job.. Yay! Would it not be possible to use something to hold the actual impeller itself while cracking the bolt? Set of vice grips on it, then quick zap with a cordless impact with an allen socket? Might damage the plastic impeller, but worste case would be as you have said. Pulling the full RHS cover.

 

[GMP]

Its a weird setup, as the impeller is also threaded(not keyed to the shaft), so it can function like a jam nut (two nuts together). If its tight its a bitch. Doesn't hurt to have a look see under the cover now and then anyway.

 

[swazi_matt]

Mine was not particularly tight, but I have a plastic lockup tool that is used to install steahly fww. It screws into the sparkplug hole and stops the piston from moving all the way up

 

[Jakobi]

Right on! When I sack up and dive in there I very well may have a go at changing the powervalve setup too. I'll probably start or expand on another thread but would really like to have the valve open slightly sooner.

 

[GMP]

Again, you DO NOT want to lock the crank and torque on that impeller bolt! If it comes off easy fine, but you risk damaging the gear or stripping the button head bolt. It doesn't have to installed very tight as loctite and the direction will prevent it from coming loose.


Edit:

Here is why you don't put any load across this part.

 

[Eric K]

Glenn,

Just got around to reading this thread.

I had the same problem - complete coolant loss on my '06 EC300 4 years ago.

My coolant went past the water pump seal into the transmission.

The engine checked out fine - full compression and everything looked good. 200+ hours and a few top end rebuilds later it still runs excellent.

As a note, prior to this failure, my stock water pump impeller at 90 hours was nearly completely eroded away. I replaced it with an LTR alum impeller.

 

[PEB]

Glen the motor should be fine I have run mine dry more times than i care to admit. Lately it has been leaking at the cap, you can hear it clear as day in the video I am editing right now. I need to send my head off to RBD as i am tired of packing so much fuel and this will surely help.

 

[GMP]

Trans is the first place I looked, because I saw no steam. It was the perfect day to hide the slow leak failure, very hot, steamy, muddy, with heavy showers.

Got the head back and all is together except the waterpump, waiting on a new cover. Hopefully I can keep the bike on the trail long enough to tweak the suspension and get used to it.

Eric and Paul, you guys have been around for years now and know the BS with the plastic impellers, thats why Les got into the alloy ones. Finding this in a new bike really pissed me off. I searched for that pic of the melted/distorted one but can't find it, probably was on the old Smackover site. It looked like one of those "gummy worm" candies the kids eat.

 

[GMP]

Here is a pic from stainless's bike last fall, not the one I was thinking about but you get the point. These should be sent to the factory in Spain.

 

[Jakobi]

Stop scaring me Glenn!

 

[swazi_matt]

it seems like they oversize the plastic impeller slightly and let the cover/impeller contact grind itself down, all the pics of plastic seem to show some wear, mine also had it and i ordered a second gasket thinking that the alloy impeller would also grind but it doesnt

glad i changed mine

 

[GMP]

Not really IMO. My engineering assesment is that the covers are not finnished consistantly, and if contact is made, it can lead to this and the broken shafts/gears like that seen on at least one guy's Nambo here. Like I said before, in addition to the impeller that shaft and gear are relatively weak, not intended to transfer any torque.

Get that s#$t out of the motor and fit the alloy part. Take the side cover off and do it on the bench. Snug the cover down with a gasket and verify that there is no impeller/cover contact. If there is and/or the casting is not machined/rough, clean it up with some sandpaper using the impeller as a backing. Form a "cone" of paper and twist it in your fingers with the impeller to resurface.

 

[Vindicator]

Take the side cover off and do it on the bench.

Are you referring to the water pump cover or the entire right side cover ? Can it be done just by taking the water pump cover ?

 

[GMP]

If the impeller bolt is not frozen to the shaft, you can do it through the pump cover, BUT, there is no real way to tell if the new alloy impeller (which is slightly deeper) will contact the cover unless its a gross contact. With the side cover off, you can snug up the pump cover and spin the pump shaft by hand. You will feel any interference. I leave nothing to chance lately, everything must be checked if it can be.