hi, 2007 gilera dna 50 water pump seal leaking into transmission case. Ive ordered the repair kit, ive accessed the pump in the transmission by removing the oil pump, left with a large spinning belt driven cog which clearly drives the water pump. Ive accessed the other end by removing stator cover and disconnecting the water pipes. Now im stuck, i can see a small brass nut recessed back inside the engine at the stator side. Somehow i now need to pull out the cog, replace the seals and put back together???!! I cannot see any circlips that may hold the cog in place and i dont want to prise it off if its fixed somehow. Basically, now i have access to both ends of the waterpump, what do i do now? Thanks
Get the Haynes Piaggio manual, it tell's you how to do it. You don't have to strip the engine to replace the seal, everyone tell's you that you need to strip the engine, not true. The water pump pulley just pull's off, the brass impeller nut is LEFT HAND THREAD! You'll need a slide hammer to do the job. Think about it and read the book!
I've undone the impeller, removed the circling in front of the bearing and currently trying to remove the shaft with mole grips...not happening! How will a slide hammer grip the shaft?
your not going to yank that out with mole grips. the way the shaft is made via factory is the two bearings are pressure fitted to the shaft itself, then set into the case with a bearing seater tool. heres the crude way of getting it out, once impeller is removed fashion up a crude slide hammer ( old lump hammer top and a steal shaft with a couple big nuts welded on then end,) now your going to weld that slide hammer tip to the shaft on left side of the case, and give it a couple slides home so it pulls that shaft and the two bearings out. grab a drill bit and inside that hole is a rubber/plastic/metal cap, its gotta come out. once all thats done you insert the new cap with the rebuild kit then you get that new hsaft and everything else and fit it back. once done your home and dry, bolt on impeller close it all up prime the collant system and away you go. i never seen it done but was told a couple times by folks ( i looked at a dna before i got the sym jet i own, again that dna needed a waterpump full rebuild inc shaft ) thats how a couple folks told me how to do it, i passed the dna up and just went air cooled ) again i passed up the dna as i didnt like the idea of welding stuff to the shaft of the failed waterpump im sure theres another way to do it and your really best looking into a haynes manual to get the right way ( welding stuff to shafts dont sound right and it kinda sounds like some redneck cowboy job )
The slide hammer has a thread on the end, I welded a 8mm long socket to nut to fit S/H. The 8mm socket has a hole at the end with a small bolt that you tighten on the pump shaft. I'll put some photos up tomorrow!
Cheers guys, ive seen the welding idea on youtube and for fear of setting fire to my bike i wont be doing that. The other tool sounds easy enough but i reckon ill remove the engine and split it. I can check my piston and stuff as well then.
This is my pump shaft/seal extractor. First pic is the std slide hammer then bit that slides over the pump shaft and bolts on, the 4th n 5th pic is the ground down allen bolt that I use to hook through the seal to pull it out. Works every time!
Nicely done and thanks for the pictures. It looks like something i could copy and manage to make.... i hope!
