FORUM CLASSIFIEDS DIFFLOCK.com Links & Networks
Forum Homepage
Log in
Profile
Search
Private Messages
Forum Members
Register
Classified Ads
Search Ads
Place New Ad
My ads
Place your classified
ads here for FREE
NB: Adverts placed in the general
forum areas will be deleted
Difflock Homepage
Online Shop
Contact Us
FAQ
Calendar
Garage
Facebook
Twitter
Youtube
Advertise With Us - Reach your target market by advertising on the Difflock.com forum.
Click here or call 0845 125 9407


404 8 Speed Conversion WITH a PTOI

 
 
Post new topic   Reply to topic    Difflock Forum Index -> Mercedes & Unimog
View previous topic :: View next topic  
Author Message
TigerMog
Winch Assistant


Joined: 25 Aug 2008
Odometer: 88
Location: Marchwood



PostPosted: Sat Oct 10, 2009 6:37 pm    Post subject: 404 8 Speed Conversion WITH a PTOI Reply with quote

I know there is already a substantial thread on the 8 speed conversion, but I am doing the conversion and keeping my PTO as well so thought I would start a new one.

This is a work in progress, so I will add to the thread as I complete the project. If I wait until the end I will forget things guaranteed.

Prep: I am making a new tipper bed for my Mog so I have no bed on which was handy for accessing things, but I dont believe it is required. You can pull the top off of the gear box without removing the bed or the cab. Having the bed off just made it really easy.

You will have to remove the canvas bit that all of the levers run through into the cab. You also have to take off the metal panel that covers the transmission. I will try to add photos to show this.

Remove the parking brake assembly and the 4x4 / differential lock lever. This is just 2 pins, and 4 bolts, very easy.

Take out all of the bolts holding the transmission top in place. The entire top piece then lifts upwards into the cab with no problem. The arm to engage the PTO is pretty long and goes deep into the gear box, be careful it is totally clear as you you remove the top plate.

The shift plate with all of the linkages is now exposed. It is not fastened down with anything. A tap of the hammer should free it of the gasket material and it lifts off easily.

Modification:

Although things sound complicated, once you crack open the gear box and play with it, sliding things around you will see it is d gear box that goes from the dead simple.

My design is to shorten the arm inside the gear box that goes from the forward/reverse lever to the forward/reverse slider. I will then build up the high/low range slider to the same height as the forward/reverse slider. Everything then lines up perfectly to use my forward/reverse lever to operate the high/low range selector instead.

The slider for forward reverse is NOT in line with the PTO, it sits well off to the side under a nice flat section of the gear box top. Machine a flat spot on the case top and mount a new pillar and lever to operate the forward/reverse selector. The instructions DX has posted for the 8 speed conversion even gives a detailed schematic for making the new pillar and lever.

This should leave me with a new forward/reverse lever just beside my leg, and what WAS the forward/reverse lever will now be my high/low selection lever.

Not nearly as complicated as it all sounds. I will take more pics through the week as I do the machining bits and put it back together.

__________________________________
cheers,
Dan

Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but, rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming "@#$%, what a ride!"
Back to top
View user's profile Send private message
TigerMog
Winch Assistant


Joined: 25 Aug 2008
Odometer: 88
Location: Marchwood



PostPosted: Sat Oct 10, 2009 6:39 pm    Post subject: Reply with quote

8 speed conversion with PTO...not sure where that extra "I" came from.
__________________________________
cheers,
Dan

Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but, rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming "@#$%, what a ride!"
Back to top
View user's profile Send private message
Turnip
Just got MTs


Joined: 29 Oct 2007
Odometer: 192
Location: Gloucestershire



PostPosted: Sun Oct 11, 2009 8:25 am    Post subject: Reply with quote

Interesting bit of lateral thinking there Tigermog - using the different levers. Can you show us some detail on where you machine the new location when you do it?
Just a hint when it comes to reassembly......I found that removing that lid to disable the reverse interlock - which doesnt make any difference by the way - you still only get reverse in low.
Removal was easy bit when I came to reassemble the forks into the gears - because the box tilts back the gears kept sliding away. If you jack the back of the Mog up a bit to level the box - it all stays put - simple but made a big difference!
If you need a tipper back for yours - consider the Ally transit butt I have put on mine - spot on for width - couldnt have made it better! Drove a small Dowty pump from the front of the PTO and jobs jobbed - can do pics if you want them?

__________________________________
Never mistake the edge of your rut for the horizon.........
Back to top
View user's profile Send private message
TigerMog
Winch Assistant


Joined: 25 Aug 2008
Odometer: 88
Location: Marchwood



PostPosted: Sun Oct 11, 2009 8:53 am    Post subject: Reply with quote

Turnip,

Thank you for that! I hadn't thought about the gears slipping about, but jacking up the tail end is brilliant. I will remember it when it comes time for reassembly.

I made my own bed for it which I will be mounting this week as soon as the gear box is back together. I may well ask you for details on the pump setup you used though.

Right now finishing the gearbox, new petrol tank, mounting the bed, tuning the LPG, and mounting the 4 speed crawler gears are all the excitement I can handle. I hope to actually drive it again soon and stop pulling spanners all the time!

__________________________________
cheers,
Dan

Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but, rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming "@#$%, what a ride!"
Back to top
View user's profile Send private message
Turnip
Just got MTs


Joined: 29 Oct 2007
Odometer: 192
Location: Gloucestershire



PostPosted: Sun Oct 11, 2009 9:30 am    Post subject: Reply with quote

AHH - a man with four speed crawler gears - I am not worthy!! 2 speed ones would be enough for me .... but they seem to cost more than my Mog!! I could really use some so that I can get the revs up when using my trailed mower without going so fast I hit the trees!
If you use a small tipping bed then somewhere i have a Ratcliff tailift electropac which I was going to use but the reservoir would only support a small ram as standard.
I must admit it is nice having hydraulic, electric and air on board! Air is great for the diff locks - easy to rig too!

__________________________________
Never mistake the edge of your rut for the horizon.........
Back to top
View user's profile Send private message
mike97
Guest








PostPosted: Sun Oct 11, 2009 4:17 pm    Post subject: Reply with quote

Hi Dan,
Glad to hear the 8 speed conversion is going ahead, well worth it when its done. Looking forward to seeing how you get on with fitting the extra lever.
Im looking for a PTO myself if you or anyone know of one going? so I can use it to power a hydraulic pump for my winch.
First of all I need to spend a few hours with the pressure washer after last weekend!
cheers Mike
Back to top
mike97
Guest








PostPosted: Sun Oct 18, 2009 9:13 am    Post subject: Reply with quote

Just stumbled across this site
http://www.eulan.de/torsten/Schaltplattenumbau_0706.pdf

Now my German is not good, but from looking at the pictures I'm guessing this method allows 8 speed but still using the main gear lever to select hi / low??

Anyone know how to translate to english??

Mike
Back to top
dxmedia
Mud Obsessed


Joined: 10 Dec 2008
Odometer: 2185




PostPosted: Sun Oct 18, 2009 11:01 am    Post subject: Reply with quote

Try this.

Not brilliant but better for us non german speakers.

http://translate.google.com/translate?prev=hp&a...p;history_state0=
Back to top
View user's profile Send private message
mike97
Guest








PostPosted: Wed Nov 11, 2009 8:34 pm    Post subject: Reply with quote

Hi Folks,
Having aquired a pto I've had to re-think my existing 8 speed set up. Well after a few evenings tinkering i've got it sorted!
With my previous setup I used the pto lever to select hi/ low, Now all levers do what they should in the standard way.
The extra two gears are selected on the main gearlever and hi/ low is selected on the main lever too, like the std. setup.

Basiclally I have cut a new gate for the two new gears (3 & 4 low) welded a selector plate onto the 3&4 selector and modifyed the hi/ low sliding plate. Its difficult to explain so have added a few pics.
Std shift plate

New 3/4 gear gate and modified hi/ low plate

3/4 gear plate welded to existing 3/4 selector

Job done!


Planning on bolting the bits back on the box soon, keep you posted.....

Mike
Back to top
s.frimodt
Just got MTs


Joined: 08 Sep 2009
Odometer: 170




PostPosted: Fri Nov 13, 2009 4:01 pm    Post subject: Reply with quote

Looks really interesting, might just be the way I will do it, great idea
__________________________________
Søren Frimodt Petersen
(Jysk Mog Crawlers)
'64 Mog 404, 49" Nokia MPT's, 120bhp M180, rollcage etc.

'53 Land Rover Series 1, awaiting some minor upgrades
Back to top
View user's profile Send private message
Turnip
Just got MTs


Joined: 29 Oct 2007
Odometer: 192
Location: Gloucestershire



PostPosted: Sun Jan 03, 2010 8:44 pm    Post subject: Reply with quote

Mike,
Have you got this conversion running yet? Can you give a bit of detail on the main sliding plate? It looks like you have cut the end out and made a larger "window"
Also from what I can see - using this method your gear progression is different in the high and low box? That is to say that in the high box - you ascend the gears by pushing away, whilst in the low box the gears get higher as they come towards you? Or am I getting that wrong?

Phil

__________________________________
Never mistake the edge of your rut for the horizon.........
Back to top
View user's profile Send private message
Turnip
Just got MTs


Joined: 29 Oct 2007
Odometer: 192
Location: Gloucestershire



PostPosted: Sun Jan 03, 2010 8:45 pm    Post subject: Reply with quote

Mike,
Have you got this conversion running yet? Can you give a bit of detail on the main sliding plate? It looks like you have cut the end out and made a larger "window"
Also from what I can see - using this method your gear progression is different in the high and low box? That is to say that in the high box - you ascend the gears by pushing away, whilst in the low box the gears get higher as they come towards you? Or am I getting that wrong?

Phil

__________________________________
Never mistake the edge of your rut for the horizon.........
Back to top
View user's profile Send private message
mike97
Guest








PostPosted: Tue Jan 05, 2010 5:34 pm    Post subject: Reply with quote

Hi Phil,
Yep, I have had the Mog back on the road for a while now, the gearbox is just great!
Your right, in high the gears ascend away from you (as normal) and in low they ascend towards you, this may seem a bit odd but you get used to it real quick, I don't think about anymore.

The sliding plate still selects high and low as per normal, but as you spotted I have made the cut-out wider in order to select 3 & 4th low.
The other mod I made not shown in the pics is a spring and plunger that acts ontop of the sliding plate to just hold it in the hi or low position.

So now i've got 8 speed sorted, pto fitted and working, just need to work out how to connect the pto to a hydraulic gear pump??

Mike
Back to top
Turnip
Just got MTs


Joined: 29 Oct 2007
Odometer: 192
Location: Gloucestershire



PostPosted: Tue Jan 05, 2010 6:28 pm    Post subject: Reply with quote

Hi Mike,
Thanks for that, did you do any sketches of the plate and plunger etc?

With the hydraulic pump - Ive already done that and I will try and take some pics for you at the weekend.
I clamped a 5mm plate onto the forward edge of the adaptor that goes between gbox and clutch using 3 of the existing bolt holes. I mounted my Dowty pump onto this and made a custom coupling to drive it - so my pump is on the front of the PTO - the rear of the PTO has a shaft via UJs and plummer blocks right to the back of the Mog then dropped by chain and sprockets to central PTO to power mower, pressure washer etc. I can do detail if you need it?
The PTO is VERY slow and you need to calculate your pump size carefully or you will need to rev your nuts off - have data if reqd.
Phil

__________________________________
Never mistake the edge of your rut for the horizon.........
Back to top
View user's profile Send private message
mike97
Guest








PostPosted: Tue Jan 05, 2010 7:25 pm    Post subject: Reply with quote

Phil,
I'll have a look back through my photos to see if i have a pic of the plunger, it was basic, just a spring with a ballbearing on the end pushing onto the top of the sliding plate which I drilled a couple of small indents in to for the ball to sit in. much like the set up used on many gearbox selector rods to hold them in postition.
I would be intrested to to see your hyd. set up, All the tractor pto pumps i have seen run through a small gearbox to increase the pump speed, I guess 540 rpm is too slow for most pumps. I plan to run a winch. The winch motor is a Danfoss unit I'll find out what flow and pressure it requires, I really dont want the winch to be painfully slow Sad
cheers Mike
Back to top
Turnip
Just got MTs


Joined: 29 Oct 2007
Odometer: 192
Location: Gloucestershire



PostPosted: Tue Jan 05, 2010 8:18 pm    Post subject: Reply with quote

Mike,
Yes I know the tractor type step up boxes, I run one on my Fergi for the digger, most are 3:1 or near that. Most of the pumps I have are rated in cc per rev and you have the option of a big pump going slow or a small one going fast! What I have found in practice is that the slower the pump goes (dowty type gear pump) the better condition it has to be because of "slip" or oil by passing the gear ends and sides.
Also on the Mog the centreline of the PTO is very close to the gearbox, so if you want to close couple as I did, you cannot have a very big diameter pump before it fouls.
If you long couple via a cardan shaft, you can use what you want, but I needed both sides of my PTO.
I have not measured engine revs v PTO revs but my impression is that to get 540 rpm you would be screaming. I will try and get these figures for you.
Phil.

__________________________________
Never mistake the edge of your rut for the horizon.........
Back to top
View user's profile Send private message
Turnip
Just got MTs


Joined: 29 Oct 2007
Odometer: 192
Location: Gloucestershire



PostPosted: Sat Jan 09, 2010 8:01 pm    Post subject: PTO Hyd pump Reply with quote

Mike - I have taken some pics of the hydraulic pump I am using - I will look up the size but it is a Dowty unit. I have a side mounted hyd tank and use this to tip the butt.
It is a 4" dia double ram and it is quite slow to tip at tickover. I will measure the PTO speed next time she is out but my impression is that tickover speed is about 150 rev /min, this is really too slow for a gear pump and most of the graphs dont start until 500 rev, I believe this is due to the aforementioned "slip" past the moving parts.
There are several ways around this - one to use a carden shaft and step up box as you said and another to use a Kawasaki radial piston pump or a swashplate pump instead. Dont forget - see pics there is very little radial clearance adjacent to the PTO centreline.

Phil

__________________________________
Never mistake the edge of your rut for the horizon.........
Back to top
View user's profile Send private message
mike97
Guest








PostPosted: Sat Feb 20, 2010 2:08 pm    Post subject: Reply with quote

Hi Phil,

Thanks for the pics, very interesting. I have just installed my hydraulic pump, a slightly different approach. I'm using a small gearbox/ pump that came off a compact tractor, the pump was used to power a backhoe loader. I don't know what spec the pump is (cant find any markings on it) so im just going to rig it up to the winch and see how it goes? Hopefully I should get the hydraulics finished over the next week or so.
The pto shaft is custom made (MGB propshaft) modified flanges to fit the pump and gearbox.

cheers Mike
Back to top
Display posts from previous:   
Post new topic   Reply to topic    Difflock Forum Index -> Mercedes & Unimog All times are GMT - 12 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You can post calendar events in this forum
Facebook

Adrian Flux 2023

Service Kits

Oil Safe

Evo Oils

Join our mailing list for upcoming events, special offers, discount coupons and expert advice on the latest 4x4 products!

* indicates required





    
Powered by phpBB © phpBB Group