Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Plus 8 Front Springs

Welcome Bob, and thanks for the compliment. I've nothing to add to the above, except that I'm no fan of lowered springs for road use. If you can tackle this yourself you could buy the springs and examine the bushes when it's stripped down. You can manage without spring compressors if you use long threaded studs. My motorbike compressors were disappointing as you'll see in the pics. You should fit Mulfab steering bearings though. Now mine is bedded in it's great. You need shortrer springs to accommodate the bearing depth, also from Mulfab. I had a sloppy kingpin at 10k miles.
Hard chrome kingpins are most wear resistant apparently.

Hi Bob, It could be the springs, but I am convinced that stick-slip also causes ND effect. To check, pushing down on the car is a bit difficult because the wings or bumper will flex too much and you cant see if the suspension is moving or the tires as as Cereal says. With the car on a lift or ramp you get under it (or lying on your back, head and shoulders under the front of the car) grab the cross-bar and jank it up and down. In my case I could not move the suspension at all with my whole weight on it but the car started bobbing on the tires with that very familiar frequency. (thats how I found out) After I sorted it I could move it up and down with very little stick slip. ND effect cured!!! Cheers J

Couple more points maybe;
-If you replace springs and add bearings, make sure the rebounds are short enough so that they are just free (able to rotate by hand) when the car is standing on the uppers.
-Fit gaitors on the rebounds to prevent premature wear and stick-slip.
-Use grease with Moly frequently.
Cheers J

Dave and JJW, thanks for the tips.

Dave, I've read your Kingpin "How To" a couple of times now and will read it a couple more. An outstanding contribution if you don't mind my saying so, leaves so called "pro-manuals" in the shade.

What was it that persuaded you to do the job in the first place? Could you feel something amiss or was it the desire to go for the steering bearings? I read your conclusion but was there any downside to having the bearings vs the old blades? I'm sure on another forum I've seen folks vote both ways although to me bearings seem a good idea. I don't suppose you put a micrometer on the old vs new Kingpin dia?

JJW, I'll have a crawl under the car and have a play. Simplistically, you're suggesting that if it doesn't move, moves reluctantly or only on the bounce of the tyres then it's likely I've a dose of stick slip on my hands, despite the 180 springs, and therefore it's the Kingpin route for a cure?

This sounds like it might to turn out to be quite a shopping list.

Hi Bob,
Indeed, if you cant move the suspension at all or if you get 1/2 to 3/4" travel but it will not go back to neutral by itself, I would say you have too much stiction. (try on one side to get maximum force into it) Note that this is based on my roadster set-up with softer springs and no preload on the rebound springs, not sure how it would feel on your car. If you cant move it at all, use a jack to lift the front up while looking at the suspension. If you have too much stiction you will see the suspention only move in one jolt when the tires are almost off the ground and also come back in one jolt when you lower the car again.
Stiction is usually caused by wear on the lower bushes (road grime) If the lower get room the upper starts to pich. To check for KP wear, jack up the car, apply the brake to shut out the wheelbearing, grab the tire top/bottom and rock it. Judgement call, if you can see or hear it move AND you have stiction you'll know what to do. Have you seen the excellent stuff on the spring set up on Morganatica? see spring rates and springs interaction Cheers J

A long story Bob. The first owner didn't like the steering kickback and had some uprated stub axles fitted after 2-3k miles. This is because the angle of the track rods was levelled around 06/07 to reduce bump steer. From what I found when I took it apart, it was obvious that the new stubs had not been reamered very well, because there was a lot of play in the nearside. This was picked up at the MOT at around 6500 miles and I doubted the tester. It did actually pass but with an advisory. The folowing year I went to my 'village' MOT station where I've taken cars for years, and watched what happened when the tyre was levered. There was a lot of play. I made it do another year, then got the parts. The steering bearing conversion is a no-brainer really if the kingpins need doing. The difference is amazing. You can see from my how to thread that the pins were badly worn in well under 10k, probably due to lack of grease, and somebody had fitted upper nipples without checking the pins, and since the old pins had no drilling, the top nipples were decorative only. In 05 you only got one nipple per side as standard, and to be honest, the top one doesn't do much. So that's the story. Glad you like my style, but it's simply that pictures are worth a thousand words. Pictures are what sets this forum so far above all the others. Narrative and line drawings are OK, but close up pics define the job better than any other way. All workshop manuals should be done that way now.
Knowing that the reamering had been done too wide, made me very wary about doing mine - knowing when enough is right. There comes a point when the pin will go through with some effort, but barely turns. Too tight will give stiction - the very thing you want to avoid, but too loose is building in wear. That judgement call can't be defined in writing, but all I can say is that mine were quite tight, but have proved to be great on the road.
The other consideration is tyre pressures. On 22psi and zero clicks on the AVO's pre-kingpins I was getting the bobbing. Three clicks stopped that and I'm now on four clicks. I'm also running 25psi all round, and the steering is marginally lighter than at 22psi. One of the concours cars yesterday was running 18f/22r, but you could see it was laterally wobbly on such low pressures, so try 25/26 and see what happens.

Good luck with it.

JJW, blagged my ramps back off #1 son and crawled underneath, then hung onto the crossbar and nothing moved: maybe it is stiction or maybe it's the fact that I could only really get the weight of my shoulders on it so not enough of a load to give those 180lb springs something to do.....?

Next I tried your jacking method and the suspension moved as sweet and jerk free as you could wish. No jolting or anything similar. I also got no rocking whilst doing the wheel wobble test (but then neither did the MOT man last week).

So I'm open minded on the stiction effect as the evidence is so far inconclusive. Working on the basis of keeping things as simple as possible I've ordered a steering bearing bearing kit with 140lb springs from Mulfab. The downside is there's been quite a run on them and they're on about a 10 day delivery. Wonder what started all that off Mr W?

I'll fit the bearing / springs and see what happens (the springs are a no brainer anyway) - if I still get the nodding effect at least I'll know what to do about it. Especially useful as I'd not come across that explanation before. There's still a part of me that says just get it all done and out of the way - but then I'd never know......

Dave, I think the story of your car just proves again that once out of the factory gates no two Morgans are ever going to be alike. It's no wonder an advisory at 6500 miles made you doubt a few things.

I should have the steering bearing and spring kit in a few weeks time and intend to tidy a few things up down there when I do the spring swap.

Tyres are another topic, but I've been running 25psig all round ilo the 22 in the book for 2 years now. After the springs the next job is new tyres to replace what are now the 10 year old originals. Should have done it earlier but you look at them and think "they'll be OK" - but of course they're not and get harder and more dangerous by the day. Car should be feeling good again by August.

if your tyres that are that old, then the side walls will have degraded because of UVF rays, so it really is a 'change them' situation
Cheers,
G

Changing the 20 year old tyres on my 4/4 transformed it, the rutherford springs transformed it further. I have no idea about plus 8's but running my car with 26psi was pretty uncomfortable when on bumpy A & B roads.