"Better than RTV Fix,....

So, picked up a near mint 01 Z400 E offroad dirtbike a few weeks back, rejetted, running awesome, full FMF, Manual Cam adjuster swap and just discovered on my first real days ride on it that I had the dreaded water pump coolant leak, SUCKED, was leaking from the large side cover gasket at the bottom. I tore it down earlier and gave the ceramic piece or crap seal a good look see, I had read where most used some RTV sealant to make the seal fit tighter to the impeller shaft with good results, naaahh, not me, I never thought that was a good idea, upon looking at the seal I noticed that the ceramic part was pretty wide only the thin little sweep that came in contact with the impeller shaft way to minimul, shame on you Suzuki, I took out an oring kit that I have and found an oring seal that was small enough and tight enough to slide down the shaft and fit perfectly into the ceramic seal creating a perfect water tight seal, causing more of a double seal. Well, rubbed a little brake fluid on the new seal, as I always do on all my seals, (makes rubber seal even tighter) buttoned it back up, fresh coolant, oil and filter and working flawlessly, took several tripps around the neighborhood on er and good and hot it is still working perfectly. I'm a hundred percent confident in my repair as opposed to the RTV idea, just wanted to let anyone else who runs in to this problem know to try the oring idea over the RTV fix. :thumbsup:

pics would have been nice.and oring diameter...but good to know

Yea, I thought of that after the fact, I usually keep the camera on hand for such projects but wasn't originally planning on doing it today. If you pick a universal oring kit, they start out very small and with a little trial and error you can find the right one, the sizes are actually worn off of my kit so not much help there either,...:thumbsup:

I see what you are saying. However my theory is the leak is the result of the rubber backed ceramic disc slipping inside the impeller. The disc is driven from the friction of the rubber lip on the OD. So bonding it in place with RTV seems to make sense. My experience is I had the leak. 1st try I just cleaned and put it back together with no repair. Lasted about 6 months. 2nd try I used Ultra black between the disc and the impeller. Lasted about 8 years. 3rd try I used Ultra Gray between the disc and the impeller. In servie about 2 years and counting.

I see what you are saying. However my theory is the leak is the result of the rubber backed ceramic disc slipping inside the impeller. The disc is driven from the friction of the rubber lip on the OD. So bonding it in place with RTV seems to make sense. My experience is I had the leak. 1st try I just cleaned and put it back together with no repair. Lasted about 6 months. 2nd try I used Ultra black between the disc and the impeller. Lasted about 8 years. 3rd try I used Ultra Gray between the disc and the impeller. In servie about 2 years and counting.

Sounds like pretty good results, the oring I put on the shaft actually squeezed tightly into the gap between shaft and ceramic seal, securing everything tightly in place, I don't forsee any issues every arising from it but I will post back after a few long hot days riding here soon.:thumbsup:

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