How does PSA get the HDi so smooth...

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citroenxm
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How does PSA get the HDi so smooth...

Unread post by citroenxm »

Well.. I may have one of the answers... :D

Ive had to look into a slipped belt on a HDi which has gone too far and taken out the Rocker fingers..

So I stripped off the spare head, only to find that the Rocker Fingers, are more then just a finger.. they have got ROLLER bearings in contact between the Cam and Finger! The clearence is a Hydraulic Adjuster..

The next thing I noticed was how much small the Valve stem is compared to an XUD.. However being a Valve Directly Over piston design, the rocker fingers go in stead of the Cam..

The cam shaft in in a 5 cap bearing carrier frame, well its not a frame its the top half of the bearing orface...

I shall take some pics when I come to do the car either later this afternoon or tomorrow afternoon..

A very nice piece of kit if you ask me!!

Paul
Sharing a pug 207 1.6 hdi Sw 16v.
M reg Xm 2.1 td auto exclusive S2 269k and rising
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DickieG
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Unread post by DickieG »

Rollers on the rockers arms were brought in by BMW many years ago not so much for smoothness but for improving fuel economy due to less drag on the camshaft, brilliant and simple idea for the breakable rocker arms.
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Ross_K
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Unread post by Ross_K »

Hard to beat this for smoooth:
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XantiaDaveEire
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Unread post by XantiaDaveEire »

Ross_K wrote:Hard to beat this for smoooth:
Glued down is it ? :lol: :lol:
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Dippy
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Unread post by Dippy »

Ross_K wrote:Hard to beat this for smoooth:
Not seen that done since the early 70's , We used to stand a 10p coin ( much thinner) on edge on the Mazda RX3 / 4 Bonnets and give them FULL Revs :D

it never wavered ! there was absolutely no sense of mechanical movement inside the cars , if it wasn't for the rev counter and jet turbine exhaust noise when accelerating you'd swear the engine had stopped ......

At tickover speeds , when the bonnet was lifted the only occasional faint noise was the rustle of the fan belt on tickover.


Impressed the punters no end :)

Until the 70's Oil Crisis :cry:
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Gibbo2286
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Unread post by Gibbo2286 »

Rolls Royce were doing that in the 1920s with an old penny.
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Paul-R
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Unread post by Paul-R »

Dippy wrote:We used to stand a 10p coin
Gibbo2286 wrote:Rolls Royce were doing that in the 1920s with an old penny.
That's inflation for you...
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

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Dippy
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Unread post by Dippy »

Gibbo2286 wrote:Rolls Royce were doing that in the 1920s with an old penny.
:D never had enough pennies to buy one , I liked the Citroen suspension on the Shadows though.
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Dippy
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Unread post by Dippy »

Paul-R wrote:
Dippy wrote:We used to stand a 10p coin
Gibbo2286 wrote:Rolls Royce were doing that in the 1920s with an old penny.
That's inflation for you...
LUV it :D Very Droll Sir......
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