Wandering steering

[Rdav1s]

‘89 syncro 1.6 TD twin locks.

Hi all,

I’m sure this has been covered as no way unique to me.
Over 50mph and the steering is fine until a gust of wind or a truck sucks her in!

My question is, do I change the rack and bushes. If the bushes, which ones. If the rack, what’s the best one out their?

Thanks.

[Aidan]

this may be more to do with how the steering geometry is set up, you may have the caster angle set wrongly, possibly because you have bigger tyres on and the tie rods adjusted to pull the wheels forward in order to stop the tyres rubbing on the back of the wheel arches, or the toe in may be wrong or the camber so first thing would be take it to a garage that does suspension set ups who can read the data in the Bentley manual who can check the condition of the suspension and steering and set it up by the book and then you can make informed decisions about what if anything you change.
Personally I like the steering to react fairly quick, but if it is too quick then you get bump steer and draught steer like you are experiencing so I had brickie set it up with a little change in caster and standard toe-in to make it a little more neutral but not so much change as it becomes slow to react when turning tight into gateways and tracks when off roading. Simon understands how to set up lhd vehicles as well which some garages don't pay any attention to.
Polybushes for the rack, rubber for everything else is my preference

[clift_d]

There'll always be some movement in reaction to gusts, trucks, etc, particularly with a higher vehicle such as Syncro or a hightop, or even worse a Syncro hightop (like what we have ).

Aside from looking at geometry you should definitely, as Aidan suggests, change the steering rack bushes for new polybushes. It's a relatively easy job to do as you can leave the steering rack in situ and replace the bushes by just removing the four bolts holding it in place, provided of course you don't have any problems undoing them. You shouldn't need to replace the rack.

Tyre pressure is also a factor - harder tyres flex less, so keep your tyres at a decent pressure, and if you're not going to go offroad much then a front spoiler, if you can get one, also helps a fair bit. Also if your shock absorbers are a bit tired then your van will tend to 'wallow' somewhat. Lastly, while you're doing your steering rack bushes, you should inspect all the other bushes at the front end and see whether any others might need replacing any time soon - chances are if they've not been done since new then some will probably be on their last legs, and they will also have an impact on stability.

[mgbman]

and check the 3 steering donut coupling bushes for splits or cracks, my son's ones were replaced giving a big improvement.

[Rdav1s]

hi,

thanks for the advice. Think Aidan is prob along the right track with geometry. I have a VIN number starting 25K, which puts it in the later cast lower arm era. I have pressed steel ones fitted. Also, and I cannot believe it, but the drop link has been savagely welded and is 1 inch longer on the nearside.
im now wondering what the hell I have bought. can anyone help with the following.

if "someone" has changed the cast arms for steel ones, what else needs to be changed as well?

ARB
Drop links
anything else (hubs)

thanks

[Rdav1s]

The nearside welded droplink horror

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[Rdav1s]

A better shot

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[weimarbus]

looks like somebody has nicked your drive shaft as well.

[slowcoach]

I suppose welding them is fine, but getting the lengths wrong... ! That can't help. You can drive without the arb at all (I did it for a while when mine snapped) so it's not a mission critical part. Some might disagree

[Aidan]

the change over to cast arms happened during the 1989 model year, K, in the middle of October 1988 at chassis number K 049 497 si if your chassis number is lower than this it would have left the factory with the pressed steel arms.
Pressed steel lower control arms have the same drop link on both sides 251 411 049 F, Brickwerks I think sell new ones so maybe treat yourself to a set and ideally imho rubber drop link bushes and sleeves and syncro spec washers
What is the condition of the lower control arm rubber bushes, by now most have the bolts rust welded into the sleeves so the bolt won't come out without cutting and have displaced forward on the rubber even to the point of touching the subframe, and often compromising the set up and geometry.
You may well have to rebuild the whole front end, 30 year old vans don't improve with age. Become a full member on 80-90, join the Syncronauts, post up your location and hopefully someone local to you who is familiar with the vans will be able to lend you some support in getting it properly fixed and on the road

[Rdav1s]

looks like somebody has nicked your drive shaft as well.

And the prop shaft. I have all three now and will see what other “horrors” I come across when fitting them

[Rdav1s]

the change over to cast arms happened during the 1989 model year, K, in the middle of October 1988 at chassis number K 049 497 si if your chassis number is lower than this it would have left the factory with the pressed steel arms.
Pressed steel lower control arms have the same drop link on both sides 251 411 049 F, Brickwerks I think sell new ones so maybe treat yourself to a set and ideally imho rubber drop link bushes and sleeves and syncro spec washers
What is the condition of the lower control arm rubber bushes, by now most have the bolts rust welded into the sleeves so the bolt won't come out without cutting and have displaced forward on the rubber even to the point of touching the subframe, and often compromising the set up and geometry.
You may well have to rebuild the whole front end, 30 year old vans don't improve with age. Become a full member on 80-90, join the Syncronauts, post up your location and hopefully someone local to you who is familiar with the vans will be able to lend you some support in getting it properly fixed and on the road

Chassis number is 25KG024xxx. First reg date is Feb 89.
I will order the drop links and rubber bushes today. I came across all this due to ordering the rack poly bushes (rack is free now so fitting when they arrive)
The lower arm bolts are not welded thankfully and although the bushes appear split with age, seem ok. I will post pics later to see if you agree.
Cheers as ever for the advise

[Rdav1s]

Offside lower bush & nearside

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[kevtherev]

I polybushed every bush, renewed each bearing, shock absorber and spring.
Reset the camber & castor (on all four)
The wander never really disappeared and the sucking thing hasn't changed.
My pals van is lowered 50mm and it's hardly noticable

I guess my point is the attributes of this geometrically challenged vehicle are intrinsic to its charm and character.
They were built-in.
Plastic is expensive and only 30% harder than rubber.