Questions and Issues: Steering and Top End

Post your E12 technical questions and comments here. Please, no off-topic posts.

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gmonsen
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Joined: Tue Mar 30, 2021 1:06 pm

Questions and Issues: Steering and Top End

Post by gmonsen »

First, I have an issue with my steering I'd like some input on. I added Bilsteins, H&R lowering springs, and Ireland sway bars from and rear. The car feels much better in most situations, but there is one thing I have an issue with. When I turn the wheel, especially in tighter corners it seems, the car moves more in the direction I turned than it should have. It seems to be over-rotating. I haven't had the car aligned or re-aligned since adding the sway bars and hadn't driven it enough before the work to have experienced the problem before now. It could be as simple as needing a re-alignment, I suppose. And I know there is some difference in the worm and roller steering versus rack and pinion, but that shouldn't cause what I'm experiencing. Its fine on relatively gentle curves, but a bit unsettling on tighter curves. Any input or thoughts would be appreciated.

Second, I had the valves "re-adjusted" to see about curing the ticking coming from what appeared to be one valve. Ion the process we put on a new head gasket and changed the radiator hose and a few other minor things. The ticking is lessened but still there. They showed me the valve that was causing the ticking that remains and the vale stem seems to have been shaved at the top and so its loose in there. So, it ticks at idle and low speed. I'm thinking it may be a good idea to replace all the valves and rockers. And maybe I could get a bit more aggressive cam at the same time. Again, any thoughts or advice appreciated.

Gordon
HB528i
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Re: Questions and Issues: Steering and Top End

Post by HB528i »

Gordon, Have you checked tie-rod ends and control arm ball joints? I just replaced a worn idler arm bushing that was loose and I didn’t even know it, it fixed a slight wander issue on the freeway.
gmonsen
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Re: Questions and Issues: Steering and Top End

Post by gmonsen »

HB528i...

The shop that installed the sway bars, springs, and all SHOULD have checked the tie rod ends and control arm ball joints. I asked them to. That doesn't mean they did and I am not knowledgeable enough to do it myself. I have to take it back in to install the rebuilt compressor I got from Chris, install the Euro bumper turn signals, put the seat pads in, and will have them do an alignment. I will confirm that they checked them and report back!

Gordon
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Mike W.
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Re: Questions and Issues: Steering and Top End

Post by Mike W. »

On the front end my WAG is it's got some toe out and needs alignment. With toe out you can get some really weird transitional dynamics as the wheels pivot on the strut.

On the valves there's several options. One is to do the adjustment at the cam, not at the valve stem. I don't know that it's been covered here, but there's a lot of guys over on Mye28.com that have taken to doing it that way because of wear. However, because of the rocker arm ratio the adjustment spec is different than at the valve stem, search over there a bit to find the right spec, or compare it to the rest. You can certainly change all the valves and rockers, but keep in mind a good machine shop will trim the end of the valve stem when doing a valve just just to compensate for possible cupping on the stem. So at worst, that's an option besides new parts. Rockers can wear, both the bushing and the pad which can develop a scalloped look.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
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gmonsen
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Re: Questions and Issues: Steering and Top End

Post by gmonsen »

Thanks, Mike. I have a feeling its an alignment issue.

I'll head over there and see what I can see on the valve issue. Never thought about adjusting at the cam. I don't immediately understand how you'd do that. So, I'll read up on mye28.
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Mike W.
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Re: Questions and Issues: Steering and Top End

Post by Mike W. »

Conceptually it's easy, just stick the feeler gauge between the cam and the rocker pad. The hard part is figuring out the right size feeler gauge because the rocker ratio is not 1:1.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
canada karl
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Re: Questions and Issues: Steering and Top End

Post by canada karl »

Re valve adjust. From what I read on the My28 forum they are using .08 or .09 for the rocker arm to camshaft gap and the cam lobe should be pointing straight down towards the piston. Is this correct? Also the Haynes manual states to not adjust between the cam and rocker but I don't think that is taking into consideration the wear factor at the top of the valve that was mentioned in this discussion.
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
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Mike W.
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Re: Questions and Issues: Steering and Top End

Post by Mike W. »

canada karl wrote: Mon May 24, 2021 1:29 pm Re valve adjust. From what I read on the My28 forum they are using .08 or .09 for the rocker arm to camshaft gap and the cam lobe should be pointing straight down towards the piston. Is this correct?
That sounds about right, but keep in mind valve spec in E28 M30s was .012-.014. E12s and earlier was .010-.012. Not a huge difference and I'm not sure which if either is better. Or if you feel only one is bad, check what the others are when properly adjusted at the stem, them measure what it is at the cam.
Also the Haynes manual states to not adjust between the cam and rocker but I don't think that is taking into consideration the wear factor at the top of the valve that was mentioned in this discussion.
Yes, but... while that is the normal procedure, things happen, like wear. Also they don't list a spec for adjusting at the cam and you can't use the stem spec because the rocker isn't a 1:1 ratio.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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