rocker cover

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pgray
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rocker cover

Post by pgray » Tue Mar 31, 2009 7:12 pm

hi all i got to replace the rocker cover gasket as oil is seeping through a few bolts is it expencive job or could i do it cheers [-o<
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Re: rocker cover

Post by mikeonb4c » Tue Mar 31, 2009 7:21 pm

pgray wrote:hi all i got to replace the rocker cover gasket as oil is seeping through a few bolts is it expencive job or could i do it cheers [-o<
I got away with gently (and evenly) tightening the bolts in the area the seepage was coming from. How serious is it? It's the kind of job that - on my old cars - was easy peezy. It oughtn't to be hard even on a Bongo though I imagine the engine cover top panel may have to be unbolted for access. Also, with an aluminium cover, you need to be careful to tighten the bolts evenly (using the 'star' seuence I think they call it) and you may need a torque wrench to ensure they are properly tightened but not overtightened. Not sure if gasket sealant helps (or is a good/bad idea) but no doubt one of the techies on here will be along to advise.
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Re: rocker cover

Post by pgray » Tue Mar 31, 2009 7:24 pm

hi i have tweeked a couple but naaaa
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Re: rocker cover

Post by dandywarhol » Tue Mar 31, 2009 7:26 pm

VERY low torque on these bolts and a spacer which can get damaged if overtightened - the torque is 8nm - tiny!
No point in replacing the gasket without sealing/fitting new bolt seals
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Re: rocker cover

Post by bigdaddycain » Tue Mar 31, 2009 8:02 pm

I just put up with the slight weep...It's miniscule on mine.
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Re: rocker cover

Post by mikeonb4c » Tue Mar 31, 2009 8:27 pm

dandywarhol wrote:VERY low torque on these bolts and a spacer which can get damaged if overtightened - the torque is 8nm - tiny!
No point in replacing the gasket without sealing/fitting new bolt seals

Interesting. I can (dimly!) recall doing both pressed steel (BMC 'A' series engines?) rocker covers and aluminium rockers covers (1955 Wolsey 6/90 straight-6 I think it was on) many years ago. In all cases I did it by feel and was very cautious about how much tightening I did. I don't recall using sealant. The most important thing was to tighten them down evenly, doing each one a litle at a time. With a good (cork?) gasket for the cover to bed onto, you could tell when it was reasonably and evenly 'squished' without being 'crushed'. So maybe, from what Dandy is saying, leave the torque wrench alone and wing it - but be gentle? But a new gasket might well work wonders if the old one has no 'spring' left in it. :roll:
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Re: rocker cover

Post by dandywarhol » Wed Apr 01, 2009 12:03 am

Generally NOT the rubber gasket which leaks - it tends to be the individual bolt seals. And at a couple of quid each from Ford, bloody expensive! I used silicon sealer on my old ones.
While you're at it you might as well adjust the valve clearances - well worth it - quietens the engine and makes it a little sharper on performance :D

I did a friends last week and he instantly felt a difference without being promped!
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Re: rocker cover

Post by dom_e » Wed Apr 01, 2009 8:38 am

This sounds like something I need to do as well. We've got a fair bit of oil leaking around the rocker cover. Is this likely to cause lasting damage or significant performance loss? If not, I'll just wait until a garage can look at it when something else goes wrong. [-o<
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Re: rocker cover

Post by mikeonb4c » Wed Apr 01, 2009 2:03 pm

dandywarhol wrote:Generally NOT the rubber gasket which leaks - it tends to be the individual bolt seals. And at a couple of quid each from Ford, bloody expensive! I used silicon sealer on my old ones.
While you're at it you might as well adjust the valve clearances - well worth it - quietens the engine and makes it a little sharper on performance :D

I did a friends last week and he instantly felt a difference without being promped!
Interesting points above:

Way back when I was doing rocker covers I think the gaskets were cork. I don't think there were any bolt seals.

The reason the rocker cover was off in those days was generally - yup you've guessed - so that valve/tappet clearances could be checked and adjusted. I'm sure I asked about this with the Bongo yonks back and got some explanation as to why things had moved on since then and a Bongo clearances didn't need checking. So what's the bottom line on this - are we now saying that we should be checking them, and at what mileage intervals if so?
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Re: rocker cover

Post by dandywarhol » Wed Apr 01, 2009 2:23 pm

Yep - they're adjustable - a locknut and screw and easy to do. You check/adjust 6 at a time then turn the engine 360 degrees and do the other 6.

I generally find they're slack (which makes the valves open late and close early) but found a few which were tight (generally the valve settling into the seat in the head)

Worth doing in terms of both noise and performance IMO - every 24,000 miles or so wouldn't go amiss.
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Re: rocker cover

Post by pgray » Wed Apr 01, 2009 5:11 pm

defo needs doing because its the turbo side its not bad though only when u come up a hill she smells abit :roll: been quoted £200 :?:
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Re: rocker cover

Post by dandywarhol » Wed Apr 01, 2009 6:28 pm

£50 or so quid for the gasket/seals, hour and a half or so labour and VAT - gettin' close to 200 quid......................seems a wee bit steep but if they're doing the valve clearances at the same time.................................. :?
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Re: rocker cover

Post by pgray » Wed Apr 01, 2009 7:03 pm

yes would be nice but i dont think so could ask though
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Re: rocker cover

Post by lee13 » Sat May 16, 2009 8:35 am

also check if the oil is leaking from the oil gallerie plug on the turbo side of the head "its tricky" behind the exhaust manifold gasket 6mm allen key on a tapered plug very fine thread do not over tighten clean and apply rtv silicon to the threads only if it is regds lee
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Re: rocker cover

Post by haydn callow » Sat May 16, 2009 9:18 am

Dandy...what are the clearances>>>>>inlet/outlet ??
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