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Alfa V6 + R380 + LJ70 into SJ
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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Tue Sep 16, 2014 8:20 am    Post subject: Reply with quote

Thanks for your input, will try what you suggest before I pull it apart!
What oil pressure you running your RV8 at?
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teamidris
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Joined: 24 Feb 2008
Odometer: 3372
Location: Staffordshire UK



PostPosted: Tue Sep 16, 2014 4:19 pm    Post subject: Reply with quote

I run (tolerate) 50-60psi cold, because the main relief on the back of pump must be about that and my ARV can't keep up. The 'Teed in' 3/8" ARV is 38-40psi tested/adjusted on air and that gives the engine a range of 30 to 40 psi hot. Drag it down to 600rpm ish and it drops off more. Which with a 10 litre/min pump doing 1:0.9 ration shows how much oil an RV8 can get though! It's an old Disco block with new lifters and crank bearings, but original cam bearings and rockers (worn).
The RV8 in the Ibex up Stoke runs up to 100psi on solid lifters. I think they intend going for much more power than a pair of SU carbs Razz

Working from how I imagine it all, you get max air volume in the cylinder at low rev and max force on the bearings when the throttle is wide open. (off the lights as it were). Dry sump lets you deliver good oil flow at low engine rev. And if the oil delivered is better quality (temp and aeration) maybe more pressure isn't needed for the normal KW shaft power of an engine? (even though I doubled mine over standard)

I put a normal pipe 'T' in for the ARV, but I did consider a baby swirl chamber to de-gas the delivered oil. I placed the 'T' facing up anyway and after the filter. I know it's not really applicable to yours, but designing your own oil feed gives opportunity to really think about what's going on and have what you need Very Happy

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cynic-al
Mud Obsessed


Joined: 14 Nov 2006
Odometer: 6062
Location: scunthorpe


1989 Suzuki SJ

PostPosted: Tue Sep 16, 2014 8:25 pm    Post subject: Reply with quote

I have ms on my rv8 and it's great!

Only times it's let me down were due to the air temperature sensor getting very cold in deep water and the engine over fuelling as a result. It's been in the cabin the last few years and just picks up ambient. The v8s are very forgiving old engines as they're not tuned highly or efficient so you can get away with a lot.

The power supply on board failed, no obvious reason why but I'm its third owner and it's had a few trial end errors done on it. It was easy to track down the fault by following the ecu build manual on the Megasquirt website, each step has a test to ensure correct assembly so you just do each of those.

I have had the components on the shelf to fit a pwm idle air valve (2 wire bosch unit) but never got around to it. Cold idle splutters a bit but it's fine after the first minute of running. To use a pwm you have to change some components from the solenoid setup but the advantage is you can set any rpm you want in the software for idle and even add a fast idle button if you want to rev the engine up for winching etc.

My lambda didn't last long, water killed it, and I found the narrow band to be hard to use anyway so I bought a wide band with a narrow band simulated output. I put it in to tune the engine then take it out and run open loop.

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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Tue Sep 16, 2014 8:45 pm    Post subject: Reply with quote

Thanks, some really good tips there. PWM idle sounds a cool setup and I like the idea of removing Lambda after setting up.
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Wallop Smithy
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Joined: 01 Dec 2011
Odometer: 211
Location: Shropshire



PostPosted: Tue Sep 16, 2014 8:45 pm    Post subject: Reply with quote

cool build
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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Thu Jan 22, 2015 5:20 pm    Post subject: Reply with quote

It's been a while since I updated here but there's been some progress.
A while back I played with Megasquirt for a bit, turns out timing the engine was simple..
With motor running and laptop connected - turn off the ignition advance in the software, time the motor at idle to the TDC mark on front pulley with strobe -
That being the only mark you get these days. Alter trigger angle in software while motor is running to align the marks.
Set timing advance back to "Use Table" and it will advance according to the settings in the spark table.
For some reason I was looking for a more complicated procedure.

Engine runs beautifully (obviously off load though).

The full MS tuning process will have to wait until the vehicle is driveable but it looks like the idea is one person drives the vehicle and the other operates the laptop.
Most areas of the fuel table will be covered. Some might not, like say 6000 rpm at a light throttle opening, those areas will be interpolated with a bit of intelligent guess work.
Areas of the fuel mapping which have incorrect mixtures will be identified and the fuel table is then adjusted to correct that.
The process is repeated and eventually the mapping should be pretty good.

But if using the stock narrow band Lambda sensor tuning will be a long process.
Narrow band will show which areas of the fuel table are rich or lean but not by how much.
Wide band takes a lot of the guess work away so I reckon it's almost essential.

There's a slight complication in that wide band sensors usually have a 0 to 5 volt output (rather than 0 to 1 volt)
and so they can't be directly connected to MS.
A box of tricks is needed to convert that to a suitable input signal.
The Wideband Bosch sensor and module costs about £130 but what a time saver so it's been sourced.

As you suggested Cynic-al, for this type of vehicle it's maybe a good idea to maybe remove the sensor and run open loop once tuned.

There were a few overheating issues, replaced water pump (original had the usual cracked plastic impeller) and stat, but it turned out the problems were solved by using the correct
Alfa header tank which is T connected into the bottom rad hose. Before the stat opens there's some circulation through this and a small hose from header to top of block which is obviously necessary.
I had been using a Suzuki tank before and the Alfa engine didn't like it.

Was keen to get on with the suspension build but the oil tank venting issues were significant and needed to be resolved.
Whatever I did with breather pipes there was too much oil being thrown out of the oil tank and catch tank,
only really when the oil was hot and thin and above a continual 4000 rpm.

Looks like a combination of things caused this: pump running too fast (nearly engine speed) and poor oil tank design / undersize
for the amount of flow.

The oil return was coming back so strongly from the four sets of scavenge rotors it caused some serious activity in the top of the tank. Like a hurricane in there! The vent pipes were picking up oil.

When I bought the 5 stage pump I was advised it had previously been run at engine speed on a small block V8 at up to 9000rpm.
I assumed I could get away with a slight reduction and all would be ok. But that's clearly not the case.
From what I can see these pumps mostly seem to run around half engine speed or even down to 45% and as there's no shortage of supply pressure,
(100 psi available at 800 rpm when cold) so decided to try a new ratio of 46% of engine speed.

Also, as things stood the scavenge rotors were pulling a vacuum in the crankcase of about 4.5" mercury.
Easier to think of that as about 2 psi less pressure inside the crankcase than outside it and that's not unusual with 4 or 5 stage pump set ups.
That might not sound a lot but potentially could draw in a lot of water very quickly.
So if I run with crankcase vacuum the dipstick etc must be properly sealed for wading. The whole crankcase vacuum thing is another massive subject.
Let's just say if I want to run a crankcase vacuum the option is there.


As usual things were not easy to change.
The 34 tooth HTD drive pulley to the oil pump was mounted onto an extended crankshaft nut,
with a locking arrangement that I'd made while back.
To slow the pump down the new HTD pulley had to be reduced to the minimum size available
(22 teeth for an 8mm belt pitch) and at 20mm in the bore those are way too small to mount onto any sort of extended crank nut,
so that arrangement is now abandoned.
At this rate I'll have made three trucks before I get one that works.

To get over this I made a plate with central spigot and bolted this to the front of the vibration damper pulley.


But the outer part of vibration damper pulleys usually don't run dead true and this one was no exception.
It doesn't bother the serpentine belt but would be far from ideal for the HTD drive belt.

To rectify that I mounted the pulley in the lathe on a mandrel and skimmed the face of the bonded part of the iron pulley true.



The same mandrel was then used to hold the pulley vertically in the mill. Drilled and tapped 12 holes and additional reamed holes for location dowels.



Last edited by nj111 on Wed Sep 02, 2015 1:05 pm; edited 1 time in total
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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Thu Jan 22, 2015 5:22 pm    Post subject: Reply with quote

Then there was the plate with 20mm spigot to spin up, with holes to match the pulley. Turned from a lump of 5" steel bar and keyway milled into spigot.



So these are the bits which sort the crank end out.



And fitted


Next complication, the oil pump pulley had to be much larger (48 teeth) and off the shelf HTD pulleys are all steel and weigh 2.6kg
Given the responsive nature of the engine and the amount of bouncing around the truck will be subjected to that's way too heavy to mount on the 5/8" diameter oil pump shaft.
It would be a disaster to break the shaft off a $3500 pump.
Considered boring the centre of a steel pulley out and pressing it's outer ring onto an aluminium core, like a starter ring gear,
but there would still be a fair amount of weight and inertia in this design, so that's a simple option but not the best one.

Thought I'll buy a pilot bore 48 tooth ally pulley and tried many sources but they all said 8mm pitch aluminium HTD pulleys
are to special order with 5 week lead time and £100 plus.

Feeling frustrated, no option but to make one.

Whilst doing all this the belt width was also reduced to 20mm wide
(to minimise pulley weight and make it easier to enclose the drive).


At the time I didn't have any tooling to quickly cut the HTD tooth profile quickly, (like a gear would be cut)
so improvised with what tooling I did have.

In short- Drilled and reamed 48 holes 5.4mm diameter in an oversize blank.



Then milled outside diameter to final size.
That bit was easy enough and the circular part of the tooth profile was now technically correct
but all the teeth needed to be radiused over on the tops to perfectly blend with those reamed holes.



Did that delicate cut with 5mm end mill in 3 depths of cut, so in effect 148 cuts needed.



Last edited by nj111 on Wed Sep 02, 2015 1:07 pm; edited 1 time in total
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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Thu Jan 22, 2015 5:22 pm    Post subject: Reply with quote

Then various other tools used to remove material from the centre of the pulley.
An odd number of lightening holes always looks better to the human eye, same applies to alloy wheels, clock movements etc.





Also similar work to the other side.




Belt fit is good enough.



Finished off with 6 grub screws in awkward places to drill and tap.



Broached keyway.



With a central web 10mm wide the pulley is still substantial in section but at 300 grams it's also roughly 1/9 the weight of a solid steel one. - I'll need to make another for a spare though.
Now sourced a 2nd hand HTD hob to cut these teeth, so next one will be a lot quicker to make.

The choice of HTD belts was limited around the length I needed, next size up / down being in 10 tooth increments, so expected to be introducing an idler pulley, but everything worked out just right and an 800mm belt is the perfect length.
There's about 10mm of adjustment possible with the pump position and by some miracle this belt / pulley combination is smack in the middle of it. Something went right at last.

Never expected to have to make HTD pulleys. It slows progress.
At the end of the build I'll enclose this drive to keep the worst of the debris away from it.



Last edited by nj111 on Wed Sep 02, 2015 1:09 pm; edited 1 time in total
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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Thu Jan 22, 2015 5:24 pm    Post subject: Reply with quote

The other problem causing the oil to vent was the design of the 2nd hand oil tank which in fairness would have been ok for a pump with less return flow.
Firstly it didn't have the scavenged return oil coming into it tangentially like it should, so oil sprayed across the dead centre of the tank right below the vent outlets and hit the far wall hard and fast.
Hot oil, blasting directly below the two vent outlets was not a good scenario.
Secondly those vent outlets were too small so had a high air velocity through them making it an even worse problem as they picked up some of that return oil.

Another issue was the hole in the middle of the horizontal surge baffle plate was too small, would be fine for a 2 or 3 stage pump but it needs to be about twice the size for this pump
as at high revs the oil cant get away below the baffle fast enough, as soon as there's a few mm deep of oil on that baffle plate
it gets whipped up by the return oil / vapour.
With the top cut off here's the offending baffle with small central hole.
This also shows the oil return inlet directed straight across the centre of the tank which I don't think is right.



The tank had a rework. Tangential oil return with size increased to match the pump outlet at AN16 and an increase to AN12 for both the vents
and the baffle plate hole enlarged and it was much better but still not 100% perfect.
I've realised now this tank is basically too small in diameter, there's simply not enough volume in the top of it to cope with what's being fired into it.





I'll not keep this tank as the final one, also needs to be taller so it can be tilted over more and still provide a reliable supply to the pump.
Decided to leave the final tank design for now and build a new tank in 2mm NS4 around whatever space is available as the truck is built.



Once it's built there'll be testing at extreme angles and perhaps that will prove troublesome.
The idea is to be able to run the motor at all angles the vehicle can be driven at prior to a roll, without losing oil feed,
or dumping excessive oil to the vent tank.

In the event of a roll I'll also need to consider where the oil ends up. But I've an idea to deal with that.

The rocker covers are closed to atmosphere, but there's still a PCV valve retained which will open when the engine is not running
- to prevent condensation within the motor.

For now, happy enough with all this to get on with suspension.


Last edited by nj111 on Wed Sep 02, 2015 1:11 pm; edited 1 time in total
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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Thu Jan 22, 2015 5:25 pm    Post subject: Reply with quote

Y61 axles extracted quite easily with another toy.
High Lift Patrol




And offered up to the chassis.




The plan is to have a go at events like KOW and so choice of suspension is 14" coilovers , plus triple bypass shocks and air bump stops all round.
Expensive and perhaps not everyone's preference but many trucks are performing very well with this type of set up be it from Fox or others and to me a shock that combines the
best properties of velocity and position sensitive damping with the provision for quick and easy external adjustment is impressive.

It's also worth bearing in mind that the loadings applied to the chassis (and occupants) will not be so severe as they would be with more traditional suspension. Time will tell if I've made a good call here.

Tyres are the now well respected 40" sticky Treps.

We are also lucky in the UK to have a very helpful Fox importer (Prolinx) who I've found extremely helpful and also reasonably close to my location.

I've taken Prolinx advice and gone for a Bump travel of 60% which ends up at 181mm of vertical travel.

Droop is therefore 40% = 158mm of vertical travel.

All these numbers add up. 40" tyres means an axle centreline of nearly 20"
Add to that 8" of bump and you soon find the bonnet height is around 52".

Wheelbase is looking around 110 to 112"

So far as the links go, I've been chewing this over for a long time.
The intention is 4 link at the back and I can't see any major difficulties there, but at the front 4 link would push the engine up too high, and I have always wanted low C of G so it had to be either very long radius arms or 3 link.
Given the amount of suspension travel I've decided to go with 3 link as I feel bushes would get a fair hammering with radius arms.
The upper control arm will run between engine and n/s chassis leg which has meant widening the Suzuki chassis a little more and making an extended engine mount to suit.





This also gives a nice bit of clearance between chassis and oil pump, and also between headers and heat sensitive Polybushes.


Last edited by nj111 on Wed Sep 02, 2015 1:13 pm; edited 1 time in total
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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Thu Jan 22, 2015 5:26 pm    Post subject: Reply with quote

Heavily loaded Tabs / Brackets onto the chassis / axles will be in Weldox 700. That's EXTREMELY strong plate, used on offshore fabrications, cranes,hiabs etc,
but there is no advantage in using this unless the correct grade of flux cored Mig wire is also used.
But I need something substantial to weld these to and the 100mm x 50mm section SJ chassis has just 2.5mm wall thickness.

The front suspension needed a fair bit of planning, and was initially cycled in CAD., nothing too fancy just at full bump, ride height, full droop and full articulation.
What that did make clear was in order to accommodate the Panhard rod, hydrosteer, coilovers, bypass shocks and bump stops
it was necessary to sweep the chassis legs up (in front of the engine mountings) by about 125mm.

So it's out with motor and tranny again.



I didn't want the front of the chassis to look like a bit of box section mitred and welded on - which of course it is,
and I needed to be confident of the strength both at these joints and also right along the chassis legs to include the tabs for suspension linkages.



So after a good few hours removing every bracket from the SJ chassis I've clad the chassis legs all round with laser cut profiles, 4mm thick on the sides and 3mm on the top and bottom.





Last edited by nj111 on Wed Sep 02, 2015 1:15 pm; edited 1 time in total
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nj111
Just got MTs


Joined: 15 Dec 2010
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Location: Forest of Dean



PostPosted: Thu Jan 22, 2015 5:29 pm    Post subject: Reply with quote

I've made these deeper in vertical section in certain areas, i.e. where the height changes at the front and where those new legs were welded on.






So I now have an unusual fully double skinned Suzuki chassis.
In doing this I'm also working on the principle that a double skinned section is stronger than just one skin of thickness equivalent to the two thinner ones.
It's still quite light as there are many holes in the laser profiles. I can still easily lift the chassis to turn it over etc.

Here the top and bottom plates still have to be welded on but the sides are done so you'll get the idea.
There's a bit of thought to go into the back end still but I'm pleased with the look of the re-worked chassis.
Yes I could have scrapped the SJ Chassis and gone space frame but this way there is still a bit of Suzuki there, you just cant see it!
I've loaded it up heavily with the forklift and it looks mighty strong!




The shallow section Suzuki Chassis does give an impressive ground clearance of 23" (at ride height) and the dry sump motor means the Crank sits only 7" above that.
I think as a rough guide the crank height is usually about the Centre of Gravity for a vehicle of this type, others might know better?


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big_patrol
Mud Obsessed


Joined: 10 Sep 2006
Odometer: 2620
Location: Rossendale


1998 Nissan patrol

PostPosted: Wed Jan 28, 2015 6:11 pm    Post subject: Reply with quote

Amazing work as usual, love the updates and it all sounds like one hell of a package.
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mike328
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Joined: 10 Dec 2014
Odometer: 793
Location: Suffolk!



PostPosted: Wed Jan 28, 2015 7:22 pm    Post subject: Reply with quote

"Yes I could have scrapped the SJ Chassis and gone space frame but this way there is still a bit of Suzuki there, you just cant see it!"

I can see it!! its in the holes you cut in the plate Very Happy

keep updating, I could do with the inspiration to get in the shed to bodge up scrap with a grinder and welder.....

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nj111
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Joined: 15 Dec 2010
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PostPosted: Thu Jan 29, 2015 10:29 am    Post subject: Reply with quote

Thanks Danny, if it's half as good as your Patrol I will be well pleased.

BTW Mike those laser cut profiles, full length of the chassis £25 each including material which is a laser grade 4mm steel.
I was going to plasma them myself but not at that price! Get in the shed and make it happen!
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Eclipsed4ever
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Joined: 05 May 2012
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PostPosted: Fri Jan 30, 2015 11:19 pm    Post subject: Reply with quote

That's going to be one fabulous SJ! Still amazed with the machining work and build quality . Keep it up! Shocked
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fat zuke
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Joined: 03 Jan 2007
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PostPosted: Thu Feb 05, 2015 8:16 pm    Post subject: Reply with quote

I love it when you post more pics absolute stunning work I cant wait for the end result it will be one hell of a truck engineering at its best
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nj111
Just got MTs


Joined: 15 Dec 2010
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PostPosted: Mon Feb 09, 2015 9:54 am    Post subject: Reply with quote

Few to look at then

Detail of the chassis, this is the underside of the front before capping it off.



And after capping it off.





This is about as low as I can get the motor to clear propshaft etc











a lot to do but it’s come a long way since these days

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nj111
Just got MTs


Joined: 15 Dec 2010
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PostPosted: Mon Feb 09, 2015 9:56 am    Post subject: Reply with quote

Been having a word with the Y61 axles (with the Shotblaster) , makes it easier to strip down and weld to.





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sheepy
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Joined: 30 Sep 2014
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Location: abergavenny



PostPosted: Mon Feb 09, 2015 6:55 pm    Post subject: Reply with quote

Lovely build so far Cool
What axle setup u going for??

Cnt wait to get the shed done then progress will hopefully be quicker

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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Mon Feb 09, 2015 7:06 pm    Post subject: Reply with quote

At the moment it's looking like 3 link front with panhard and 4 link rear, johnny jointed and with 2" dia 7075 links. That might change depending upon how it all comes together in the next couple of weeks.
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noodle247
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Joined: 18 Apr 2010
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1986 Daihatsu Fourtrak

PostPosted: Sat Mar 21, 2015 10:02 pm    Post subject: Reply with quote

Is it wrong to be slightly aroused by memory alloy links? Wink

Amazing build.

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mike328
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Joined: 10 Dec 2014
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PostPosted: Sat Mar 21, 2015 10:54 pm    Post subject: Reply with quote

nope. but its slightly wrong to get people aroused by a build thread and then not keep us updated for months at a time Laughing



hows this going? any progress?

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nj111
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PostPosted: Sun Mar 22, 2015 1:05 am    Post subject: Reply with quote

Good to know there's still interest. Working on it now as it happens - 1am still in the workshop.
In the middle of a phase of this that's turned out to be another major project on its own, but it's going ok, update coming soon!
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mike328
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PostPosted: Sun Mar 22, 2015 10:33 pm    Post subject: Reply with quote

we will be here waiting for it Cool Smile
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big_patrol
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Joined: 10 Sep 2006
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1998 Nissan patrol

PostPosted: Wed Mar 25, 2015 10:38 pm    Post subject: Reply with quote

Keep up the good work. I wonder what is keeping you busy Wink
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nj111
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PostPosted: Tue Sep 22, 2015 1:42 pm    Post subject: Reply with quote

This has moved on a bit so here’s a little update.
Over last winter I’d been waiting for some lovely 17” Raceline beadlockers.
Without these clearances were unknown so couldn’t progress too much with suspension design.

But not having these worked out ok in the end as it made me look at something else which has had a major effect on inner wheel turn in and therefore a knock on effect on suspension lower link positions.

To move things on elsewhere I started looking at the Hydrosteer arrangement and soon found there are a few issues in fitting Y61 axles with Hydrosteer.
The most obvious is that on a RHD vehicle there is no front connection point for the steering link rod on the O/S knuckle.
Spot the difference.

That problem is normally “solved” by switching the stubby knuckle for one from a LHD vehicle. But given the recent popularity of using to these axles now everyone wants the same elusive part not just in the UK but also on the continent and down under.
Luckily in the early stages of looking at this Danny (BigPatrol) pointed out to me another problem.
That connection point is in completely the wrong place to steer from, even though everyone does.
Ackerman geometry is incorrect, we need the inside wheel to turn in much tighter than the outside one, and it doesn’t when steered from here.
After some investigation I found what actually happens is both wheels remain parallel at all times.

So we don’t get full lock (on inner wheel), maneuverability is compromised, it’s harder to steer out of ruts and self centering of Hydrosteer also relies on external forces. (in combination with the correct steering valve).
Thank you Danny for your knowledge and input at just the right time, I would have done the wrong thing had you not got involved!

But the Ackerman problem on Y61 axles is hard to solve so what most do is accept that it’s not ideal (or are unaware) and steer from those existing front positions and at the same time create a double shear off the top of the knuckle.

Here’s a non Y61 build but with very effective Ackerman geometry, look at the inner wheel turn in compared to the outer. My aim was to have a Y61 axle on Hydrosteer turn just like this.

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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Tue Sep 22, 2015 1:44 pm    Post subject: Reply with quote

To achieve the required Ackerman geometry a correctly shaped high steer arm is by far the best solution.
Other arrangements which involve moving the hydrosteer ram and incorporating very short links have many other drawbacks and will only give about half the Ackerman angles required.
Others are welcome to go down that route but IMO it’s ineffective and it’s much easier to alter the steer arm shape.

With the kingpin inclined from the vertical it’s not easy to calculate the correct steer arm shape.
Although we do know that arm will be heading inside the rim and towards the disc.
.
In addition to this there is no satisfactory way to secure a high steer arm to these knuckles.

Despite what some claim, 4 or 5 bolts that will by calculation withstand the force applied from the steer ram are not satisfactory in terms of impact forces.
Even Six shooters on Yotas have been known to shear all 6 bolts.

My attempt to resolve this became an extra project took a good few months of spare time and here’s the end result.
The bottom line is I got the additional inner wheel turn in I wanted.



Ackerman geometry is set as per the original Patrol and there’s a home brew Hydrosteer ram.
Below you can see where I fitted the drag link (temporarily) just to prove that the ackerman controlled by the Hydrosteer ram
exactly followed that of the original Patrol.
With no oil or seals in the ram it’s easy to go from lock to lock. It would bind against the drag link connections if the ackerman were incorrect.

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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Tue Sep 22, 2015 1:45 pm    Post subject: Reply with quote

The knuckles which previously had a plain flat top surface with four M10 holes are re-machined to provide a positive location to the steer arms.
The loading on the mounting bolts is now massively reduced.
At the same time the bolt size was enlarged to M12 and a 5th one added.



It’s not been simple to re-machine the knuckles, they are awkward to hold and there are 4 possible casting variants to be encountered.
On each type the casting is slightly different. This makes it time consuming to set each one up accurately.

New bearing carriers were spun up in Chomoly. They go through the steer arms so are much longer.
They are shimmed in the normal way, i.e. on top of the steer arm, therefore without reducing the amount that the steer arm is located on the knuckle.
Starting with 100mm dia Chromoly blanks





This much swarf from turning just two bearing carriers.







And eventually after various operations of heat treatment , machining, grinding, welding , more heat treatment,
plating etc the first batch of arms ended up like this






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nj111
Just got MTs


Joined: 15 Dec 2010
Odometer: 166
Location: Forest of Dean



PostPosted: Tue Sep 22, 2015 1:47 pm    Post subject: Reply with quote





Removal of the knuckle remains easy. Once the disc is off, just lift out the top bearing carrier, the steer arm remains attached to the knuckle by the 5th bolt. Pivot knuckle over and it comes off with lower bearing carrier still in place.


Another problem was because of the way these arms sweep out there’s no room for double shear underneath them.
A double shear fabrication would foul the knuckle on full lock. This got me wondering if double shear was essential.

It’s not normally used on these.



Nor is it fitted to these.



I chose a TRE from the Volvo FH13 above.
It’s designed to steer an axle weight of 10 tons reliably for hundreds of thousands of miles.



I’m therefore not expecting an issue with that component on an axle weight of up to about 1 ton max. So long as the seal is not damaged it will keep the dirt out far better than any rose joint and at £40 it’s on the money.
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