OzVMX Forum

Clubroom => Tech Talk => Topic started by: Rossvickicampbell on October 13, 2009, 07:56:22 pm

Title: Gearbox flush
Post by: Rossvickicampbell on October 13, 2009, 07:56:22 pm: Gents - have just had the infamous waterpump corrosion problem fixed on my CR250. How do I effectively flush out the mix of water and oil from the gearbox to ensure a) no water/oil sludge is left and b)ensure nothing I am flushing with is left as I didn't think it too bright to flush with gearbox oil (expense?) - or is this the way to go?

cheers

Rossco
Title: Re: Gearbox flush
Post by: cyclegod on October 13, 2009, 07:58:37 pm: Flush with meths as water and oil mix with it and it's cheap.
Title: Re: Gearbox flush
Post by: GD66 on October 13, 2009, 09:46:48 pm: Might have to sacrifice one from your fridge, Ross...... :D
Title: Re: Gearbox flush
Post by: Rossvickicampbell on October 13, 2009, 09:53:08 pm: yeah good on ya - how did you know!!!! ::)

and CG - just get as much of the meth out as possible and top up?
Title: Re: Gearbox flush
Post by: cyclegod on October 13, 2009, 09:56:47 pm: Quote from: Rossvickicampbell on October 13, 2009, 09:53:08 pm
yeah good on ya - how did you know!!!! ::)

and CG - just get as much of the meth out as possible and top up?

Pour half of it in and shake it about, then drain after settling, then pour other half in with drain plug out and let drip dry.
Title: Re: Gearbox flush
Post by: Davey Crocket on October 13, 2009, 10:43:15 pm: Kerosene works better. ;D
Title: Re: Gearbox flush
Post by: cyclegod on October 13, 2009, 10:52:23 pm: Quote from: Davey Crocket on October 13, 2009, 10:43:15 pm
Kerosene works better. ;D

not with water or clutch plates
Title: Re: Gearbox flush
Post by: Rossvickicampbell on October 14, 2009, 12:14:05 am: thanks gents - and GD66 you are off the Christmas card list now!!! ;D

Rossco
Title: Re: Gearbox flush
Post by: GMC on October 14, 2009, 10:07:48 am: That motor has had water sitting in it for a while as it had corroded some sections in the bottom of the casing under the clutch, the lowest point in the cover. Don't want to scare you mate, but it may be worthwhile splitting the cases to check on the gears & bearings, if your up to that sort of thing.

It should be a bit easier to flush out with the clutch cover off by laying the bike on either side to fill & drain.

Completly drowned my KX 125 in a creek crossing once, unbeknown at the time filling the gearbox full of water.
I found out after the event when draining. I filled with fresh oil, warmed it up to mix everthing up & drained it striaght away, Same again after the first short ride & it was fine after that.
Title: Re: Gearbox flush
Post by: basil44 on October 14, 2009, 10:25:23 am: Get off the computer GMC and build those QLD jobs!!! :)
Title: Re: Gearbox flush
Post by: basil44 on October 14, 2009, 10:27:25 am: And don't tell me your on your smoko break. ;D
Title: Re: Gearbox flush
Post by: GMC on October 14, 2009, 02:10:09 pm: Bugger, I’ve been sprung by one of my Boss's

Hey, I was just taking a short break after finishing some NSW & Vic. jobs
Title: Re: Gearbox flush
Post by: Rossvickicampbell on October 14, 2009, 03:03:51 pm: may just do that Geoff - thanks for the thought. Eh! at least I got my job done before smoko ;D

Rossco
Title: Re: Gearbox flush
Post by: ianscr250 on October 17, 2009, 06:47:45 pm: 100% methanol its a dry fluid wash out leave sit for a couple of days and top up the oil it will dry itself out $8.50 a litre from mas hobbies ross
Title: Re: Gearbox flush
Post by: Ji Gantor on October 29, 2009, 12:51:27 am: I would not use kerosene as it has a slight abrasive nature.
GMC is right if water was in there a while the bearings should be looked at via a good old crank splitting.
If not after a few methos fill her up with diesel and drain.

Ji
Title: Re: Gearbox flush
Post by: Viper666 on October 29, 2009, 09:49:53 am: Did my YZ250F with diesel, ran it for a about 20 seconds (On a stand) running through the gears and operating the clutch. Drained and repeated. That was 3 years ago and admitedly I haven't raced much in the last 2 years but no noises, other than the usual, no clutch slip or any side effects I can tell of.
Diesel contains oil and was often used in hydraulics in the old days.

Viper666
Title: Re: Gearbox flush
Post by: dalesween on January 11, 2010, 05:08:32 pm: thats exactly what i do,it was a tip from my older brother and it works well,fill with diesel ,run for about 20 secs with no revs and then drain. I have done that for years and it works well.Didnt ask what would happen if i gave it a rev but he said just let it idle.