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Valve clearance after HG change help 300tdi

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I've just changed the headgasket on my 300tdi and following the workshop manual the next step is to adjust the valves. I've watched a few videos and believe I'm following the proceedure correctly but the gaps between the rockers and the valve caps seems huge. I rotated the engine with the crank (clockwise, not sure if it matters) until number 5 rocker went fully down (counting from the front). Then looking at the number 4 rocker there's a gap of about 1cm. The gaps are similar for all the rockers I looked at. When i've watched videos it's been quite a small adjustment needed, have I done something wrong or it the large gap due to having changed the headgasket? Head hasn't been skimmed and I replaced with the same thickness gasket that went on.

Attempt to video it which hopefully shows what I'm talking about better than my mangled description - https://youtu.be/9t9ohLT5PLc

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valve gap needs to be set to 0.20mm on each valve.  turn the engine crankshaft pulley Clockwise as viewed from the front.

the Rule of 9 applies, https://www.quora.com/How-do-you-carry-out-a-valve-clearance-adjustment-on-a-4-cylinder-inline-engine-using-the-rule-of-nine

 

this will help you reset the correct gaps https://www.youtube.com/watch?v=hAnP3kduaFA

 

have you reseated the valve pushrods & the rockers ?

 

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There's something not right there. You've not changed any of the rockers or the pushrods at all? What about the little caps that go on top of the valve stems, are they still there?

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Thanks western, Chris has a couple of videos I've watched, I watched Mike's (Britanicca Restorations) as well. I noticed in the videos though that the gaps only needed minor adjustment and was wondering if the large gap was normal after a HG change or if something is amiss

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Thanks Tesu0san. I took the little caps off to keep them safe but they're all back on. I kept the two bolts in the end holes of the rocker to keep it together and everything seemed to be moving nicely when I reassembled. I did guestimate the 5Nm initial torque before turning 50 degrees though as neither of my torque wrenches go down that low. I tightened up by hand initially to make sure it was pulled down and seated nicely then slackened the nuts and bolts, wound them down to contact, gave them a good nip with my hand around the socket then turned 50 degrees.

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Posted (edited)

That gap is far too big, even with a different thickness HG ,the valve clearance should only have a minimal difference of a few thou, looks to me like there's something missing.

 

Edited by crwoody

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Assuming the rocker shaft is all seated correctly etc. then you must either be missing something in the pushrod side (e.g. bent/broken pushrod, cam follower/roller) or the valve is stuck partially open.

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Posted (edited)

I can't think what I've done wrong, there's so little I've put back on so far. I rotated the pistons to clean them but put them back to the exact same position they started in. Locating dowels in, HG on, head on, bolts in with air filter mount, followed the tightening proceedure, valve caps on, push rods seated, rocker shaft on

Edited by Sharp

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Panic over, it seems I didn't tighten the rocker on properly. The fixings all felt tight but must not have been on correctly once I started rotating the crank.

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Posted (edited)

Hi the rocker shaft is sitting very high , is there something Jamed beneath it. Loosen the shaft and refit the shaft that's not sitting right.

 

Andy did not see you solved it.

Edited by andy _1
Wrong post

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