Front wheels not running true to the rear wheels.

[Mervyn Spencer]

Right wheel.

Left wheel.

[Mervyn Spencer]

Hi folk, my eyes maybe playing games with me, but there definitely is something obscure about my front wheels. As can be seen in the pics they don't line up squarely with the rear wheels. As can be seen on the front axle extensions by the paint around the bolt holes been scratched I have tried all permutations. short of adjusting one extension out or in to align the wheels is not really my cup of tea. Can anyone highlight where I may have gone wrong. I have measured both the extensions and the short axle bar and they are all accurate. What I have not done is measure the angle of the extension that drops down to the wheel axle.

[MikesDexta]

Hi Mervyn
As you are looking at the front of the tractor is it just the RH wheel that's the problem as that's what it looks like from your pics (and it does look a bit weird)

I'm not well up on Dexta front wheel alignment but have you jacked up the front and checked the wheel bearings for play? The next obvious one is tracking which is covered in the manual (fig 2 page 11) which I'm sure you've read but make sure the drag links are the same length and the axle bolts in the RH axle beam are in the same holes as in the LH one (looks like they are from your pics). From the manual The adjusted length of the drag links differ because of the position of the steering drop arms and, if fitting new drag links or drag link ends, the length of each drag link will have to be adjusted individually. The approximate lengths of the drag links with track at 52 ins. (132cm) are: R.H.- 39.1 ins. (99,3cm) and L.H.- 38.4 ins. (97,5cm). The front and rear drag link ends also differ as shown in Fig.3, and care must be taken to ensure that the links are fitted correctly. Fig 2 shows this more clearly methinks.

The only other thing I can think of is the RH extension unit and/or spindle have been bashed in?

Mike

[mathias1]

According to the manual a toe in of 1/4 to 1/2 inch should be alright.
So you will have to measure the distance between the front tyres and see how much you have there.

[Mervyn Spencer]

Hi Mike,
Thanks you for your response, a couple of questions. When measuring the drag links where is your marker and reference point, e.g. do you measure the draglink tube only or is that measurement of 99.3cm and 97.5cm inclusive of the ball joint? The illustration of Fig 2 is a bit of a bugger to fathom out, I placed my hole marked 52" over hole A and bolted it up on both left and right wheel extensions, am I reading the fig 2 illustration correctly? I will have to recheck my wheel bearing play tomorrow, but just to refresh all bushes, thrust bearing for the king pin are new as well as the bearings for the wheels. The ball joints are fitted correctly as per fig 3. Tomorrow I will measure the angle of each extension bend to check that they are not distorted.

Hi Mathias,
Thanks for your response also. Measuring the toe in, do you measure from the left inside rim edge to right inside rim? I understand that should your toe in be out of line you can adjust by turning the draglinks to I would guess to the 99.3cm and 97.5 cm?

Apologies for all the questions I will report back once I have checked those angles of the left and right extensions.

Mervyn.

[mathias1]

Mervyn,

Measuring between the 2 front wheels: once at the front, once at the back. Front should be 1/2" less. This drawing can help:
https://www.repcoservice.com/hints-and- ... ifferences
Adjusting the drag links should help

[mathias1]

Mervyn,

Measuring between the 2 front wheels: once at the front, once at the back. Front should be 1/2" less. This drawing can help:
https://www.repcoservice.com/hints-and- ... ifferences
Adjusting the drag links should help

I would suggest to measure at the tyre edge

[Mervyn Spencer]

Good Morning Mathias,

Thank you for the information you posted. Last night I measured the angles of both extension sections and they were both the same, so that eliminates any distortion that may have been there. I also tried setting the draglinks as per the given lengths. Measurement was taken from front of ball joint at the steering arm to the back of the joint at the drop arm.
I am going to remove the steering box to try and ease the slight resistance when turning the steering wheel from lock to lock then establish the centre point of the steering, followed by my drag link adjustment. Oh I also did note a slight bit of play in the wheels which I will have to take up a notch on the castellated nut.
So some work to be done , wish me luck.
Mervyn.

[Timeee]

To help you diagnose whether there is an alignment problem, you could attach some string to the rear wheel rear rim at about the same height as the centre hub of the front wheel, then with it touching the edge of the rear wheel front rim, take it forward past the front wheel, keeping the string just touching the edge of the rear wheel rims. You can do this for both sides and this should help you work out where the front wheels actually are. Alternatively, use a straight piece of angle bar and draw chalk marks on the floor . Tyre shops use laser projectors for all 4 wheel alignment on motor vehicles, using string, or a piece of wood is just a far cheaper method to measure the actual amount that the front wheels are "out", or not. This procedure works well for me when setting up a plough, so it should work for your Dexta.

Timeee

[Mervyn Spencer]

Hi Tmeee,
Thank you for your tip I will try it out next week and report back.
Mervyn

[charlie63]

Mervyn,
I have spent some time up at my Dexta today and have taken some measurements and have a few things for you to try out and see if we can sort out your steering problem. You will need some help with the measuring tape.
Firstly measure from centre to centre of the rear tyres. On my Dexta this is around 521/2" being set for 12" furrows on my plough. Disconnect your track rod ends so the the front wheels can move individually. Set them as straight as you can and get a measurement from centre to centre of the front tyres. Measure the front and the back of the tyres to get them equal. This measurement should be close to the same as the measurement you got at the rear wheels. Mine is 53" at the front. If this is the case your wheels are true to the rear and the problem lies with the adjustment of the tie bars. As you will see from the photos my front wheels are pretty much in line with the centres of my rear wheels. My rear wheel centre discs are also bolted on the inside of the lugs on the outer rim. The outer bolt hole on the front axle beam is also bolted and lined up with the outer hole on the adjustable beam. This is the way I set up my steering and then adjusted the tie bars to suit making sure both drop arms on the steering box are also set pointing down centrally. All my drag link ends were replaced along with the steering box being rebuilt. The front axle had also been totally stripped and rebuilt. Hopefully this info will have been of some use to you.

Right hand wheels.



Left hand wheels.



Rear wheel disc setting.



Front Axle beam





Rear wheel measurement



Front wheel measurement.



Good luck.

[Mervyn Spencer]

Charlie,

Thank you for going to the effort of taking those measurements and pictures much appreciated.
As I mentioned in my email to you the other day I packed my steering box with grease and stuffed some grease into the steering nut which made an enormous difference, I still have about a 2 to 3inch play in the seeing wheel. I refitted the steering box onto the Dexta and coupled up the draglinks and I think I am rather close to a satisfactory alignment.
With regards the rear wheel disk you will see what I have done from the pictures I am going to attach.

[Mervyn Spencer]

I chose to fit my disks this way more for a aesthetic purpose.
I took a measurement from centre to centre of my rear wheels and arrived at 143.5mm or +- 57.4 inches, keeping in mind my tyres are 14.9.24 inch.

[Jerry Coles]

If you are ploughing then the inside face of the front right tyre must align with the inside face of the rear tyre to ensure both tyres follow the wall of the previous furrow. Doesn't this affect wheel adjustment?
IMHO
Jerry

[charlie63]

Jerry,
Im afraid I need to correct you on what your last post said. For ploughing its the wheel centres that must be closely matched or as near to each other as possible. The front wheel inner wall will not be in line with the inner wall of the rear wheels as the front wheels should not rub or run on the edge of the furrow as this would restrict the steering.