Trunnions.

[Philip]

Hi, just after a little advice, my O/S hub is a bit stiff to turn when disconnected from the rack and the car has poor self centering steering, I am assuming this is a trunnion problem. I wouldn't know what a trunnion was if it fell on my head. So I would like to know, how big a job are they to change?

[Marinanut]

They are the big metal joint at the bottom of the upright hat the hub attaches to. It should have a grease nipple on the bottom, try pumping some Castrol LM into it until it comes out the top and wiggle it about. If that doesn't work, it will need replacing.
It is not a difficult job (most things on a Marina aren't), get a Haynes manual and for once they are pretty accurate. The trunnions you want to get are called "Walford" trunnions; they sometimes pop up on eBay but someone on here will probably have a set as they are stronger and give better steering.

[Philip]

Thanks, how long should they take and what tools do I need? Do I need to heat anything up?

[JubileeNut]

Only a Kettle for your tea while you work out what you have got yourself in to!

Should be fine.

You will have to disconnect the upper joint from the shock and remove the disc and hub and back plate as you need to un-screw the up right and if the back plate and disc are there you can't un wind it. Unless you remove the tie bar and lower leg and then un screw the trunion from the up right!.

Good luck.

[Number 63]

Philip, I have just dug out an old thread where Kilroy had created a step-by-step guide for re building the front suspension which should give you most of the answers you need. As said above though, give them a good greasing first as they may not be shot, just a little stiff.
ALL YOU EVER WANTED TO KNOW ABOUT TRUNNIONS

I have made the thread a sticky in the Technical lounge so it's easy to find for future reference.

[Philip]

Hi, thanks for that, most useful. I will pump loads of grease in and work them lots back and forth and see if that works, there is no play at all. Thanks for finding the thread and thanks for the how too Kilroy.

Thanks, Phil.

[Philip]

Pumped full of grease, it feels better but still not great. Does marina steering self centre ok normally? It's just that mine doesn't self centre very well but it isn't bad to drive.

[Martec]

Hi Philip,

Yes the front suspension should self centre. With the steering arm disconnected the upright should turn freely, if not then it is usually the trunnion at fault. It needs stripping and at best cleaning, at worst replacing and if the uprights lower thread is worn then it either another good upright or a walford trunnion.

Either way for safety it needs stripping and cleaning.

The BL trunnions only have one grease nipple to grease two bearings, the Walford trunnion used two nipples, one for each bearing. I have been greasing the trunnions with a runny copper grease for years with no ill effects. As I am having difficulty finding it I'm moving over to graphite grease as neither absorb water and sofar so good.

Brian