Help with Losi hydra drive info.

Post by **Dr. Robotnik** » Wed May 09, 2007 11:26 am

Hi guys,

I am trying to find out the Losi Hydra Drive impellor part number (ebay and google aren't helping me).

I have all the parts for a hydra drive except the impellor if anyone has the part number and/or knows where to buy one I'd be very grateful.

cheers

Ed

P.S. If anyone has a copy of the manual and the other part numbers that they could scan in that would be amazing.

I have most of the parts but can't work out how it goes together and attaches to the existing slipper on your car.

Post by **atomic-carbon** » Wed May 09, 2007 12:56 pm

If you download the Losi Double XX exploded view it shows the part numbers for the hydra drive http://www.teamlosi.com/pdfs/exploded/xx.pdf as A-3130 it seems you get soem other bits as well as the impellor.

If anybody has any spur gears to suit the hydra drive please drop me a PM

Post by **shodog** » Wed May 09, 2007 1:40 pm

Ed, are you looking for the top shaft that fits the Hydra drive to the stealth?

Post by **Dr. Robotnik** » Wed May 09, 2007 4:41 pm

Thanks for the info. atomic carbon, I had just found something similar myself, it turns out I am after the Hydra drive rebuild kit which is the part number A3130 you found!

I have some spur gears for the hydra drive (used and I may need them if I get mine working) and also have found some on ebay. I'll dig the links out tomorrow. Or try searching ebay shops hydra drive (I think?).

Hi Jim, I don't know what shaft I have at the moment. I got the shaft, seals, spur gears, bearings, washers, springs and nuts in a parts lot for nothing and then bought the housings for 0.99 cents in an impulse the other day. I thought the housing kit had all I needed but I was wrong, I just need to find a rebuild kit. I want to attach my hydra drive to an MIP gearbox, I don't have a/never had a stealth to compare the shaft too, are the stealth and MIP the same? Can you link me to a pic of your shaft so I can check what I have?

Thanks for any help.

Ed

Post by **terry.sc** » Wed May 09, 2007 6:20 pm

atomic-carbon wrote: If anybody has any spur gears to suit the hydra drive please drop me a PM

Horizon Hobby UK (the old Helger Racing) seem to have plenty of hydra drive spurs in stock so can be ordered from any shop, just quote the part number:
A3904 84 Tooth 48DP (Hydra-drive-slipper) (purple)
A3906 86 Tooth 48DP (Hydra-drive-slipper) (red)
A3908 88 Tooth 48DP (Hydra-drive-slipper) (green)
A3910 90 Tooth 48DP (Hydra-drive-slipper) (orange)

I just bought a load of parts to restore my LXT from them, they have better stock of old Losi parts than Losi themselves.

All the old Losi parts they have in stock are listed here. They also have the hydra drive rebuild kit listed, and these can be ordered through any UK model shop. Can also be cheaper than buying from ebay.
http://www.horizonhobby.co.uk/autoonline/j1teamlosi/j1cars/j1kitpages/j1partspage4oldcars.html

Post by **Dr. Robotnik** » Mon May 14, 2007 9:16 am

Hi guys,

So I decided to build what I had of my hydra drive this weekend, because I had all the external parts and I wanted to know if the top shaft would fit the MIP gearbox I was rebuilding anyway. So first I checked the shaft fitted 5mm I.D. bearings and it did.

Then I tried to fit it into the gearbox and everything was fine.

Until I tried to shut the gearbox.

If we say the gearbox has the motor side (left) and the spur (right) side looking from the back to the front. On the left side the shaft is to long!! After the shaft goes through the left side bearing it hits the transmission case stopping it shutting properly.

I hope that's clear. Luckily I realised I had a gearbox half which someone has drilled a hole on the left side where the top bearing sits, so I swapped it in and the gearbox now shuts, but the shaft kind of pokes out the left side a touch.

So feeling pretty chuffed that I'd managed to use the scrap MIP gearbox and Hydra I went to rotate the gears in the box. They feel terrible, they go round ok but not smoothly like a normal tranny (all parts are clean of dirt/grease). So I took it apart again and inspected the gears. The MIP gearbox has the stock idler and diff. from MIP which I believe is 48P. The Losi top shaft also appears to be 48P but where the MIP teeth are fairly square edged the Losi gears teeth are slightly rounded and consequently the square MIP can't get into the trough of the Losi gear properly.

I have checked out the XX exploded view and my own rebuild kit instructions (I still don't have a rebuild kit this came with my hydra spares) and the shaft looks similar but not exactly the same as the Losi shaft.

So my question is. What top shaft do I have? Is it not 48P? Is it meant for this gearbox or have I got to get another one? Was there ever a Hydra drive shaft for the MIP gearbox or for 5mm I.D. bearings?

I think I could probably mod it with an old MIP idler gear, but I think I'd like to know what it is first.

I will try and take pictures tonight.

Cheers

Ed

Post by **shodog** » Mon May 14, 2007 9:51 am

The MIP gears are a metric pitch because they were a copy of the Tamiya sand scorcher gears. I have never heard of a hydra top shaft for an MIP gear box but that doesn't mean one was ever made.

Post by **Dr. Robotnik** » Mon May 14, 2007 10:58 am

Hi shodog,

Thanks for your reply. I was aware that the MIP gears were the same as the Tamiya SRB and I had thought they were a standard 48P.

I had made this assumption as I am trying to make an MIP SP25 (MIP 4wd front prop shaft) and I bought a 15T Associated 48P pinion to act as the gear and it meshes fine.

But are Losi gears not a metric 48P? Is that where my problem lies?

I am beginning to feel I have a standard Losi gearbox hydra topshaft but don't know as it could be the shaft for the RC10 stealth (is there one) and if so what pitch are those teeth?

Pictures tonight should make things easier

Cheers

Ed

Post by **wyldbill** » Mon May 14, 2007 12:43 pm

if youre topshaft has a spacer machined on the spur geas side of the shaft then it is a losi. assocatied topshafts dont have the spacer and were designed to be put in the tranny standard or reversed. losi trannys were designed to be put in one way only and had one bearing mounted further out on the spur gear side that's why the spacer is there.some early losi xx topshafts had a 3 piece topshat where the gear,shaft,and spacer all came apart,but then they started making them all as one piece. losi oval guys always look for the 3 piece shaft because they make mid motor conversions easier and they still fit current transmissions.

Post by **Tim W.** » Sun Jul 22, 2007 12:32 am

I have some hydra drives
Is there another Fluid you can use besides the losi stuff

Post by **Janus** » Sun Jul 22, 2007 3:33 am

Tim W. wrote:I have some hydra drives
Is there another Fluid you can use besides the losi stuff

Pretty sure a heavy 1/8 scale diff fluid would do the job, but not certain on which wt you'd exacly need.

p.s. exploded hydra: http://www.teamlosi.com/pdfs/exploded/xxcr.pdf (last page)

Post by **Tim W.** » Tue Jul 24, 2007 1:31 am

How thick of diff fluid do you guys think is pretty close to the losi fluid

Post by **Bikerbob** » Mon Jul 30, 2007 10:41 pm

I know people who would use current shock fluids,

Usually between 60 - 100 wt.. if you are racing this then it will make a difference.. if you are not.. then it really does not make much at all.

Thicker the fluid the faster it will lock up..

James

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