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John W · Posted: Wed Mar 03, 2010 5:06 pm Post subject: Engine Knock with Solid Lifters

Right where to start, mate of mine has a engine rattle / knock on his C20LET, has a std bottom end he's replaced all bearings on, new oil pump, new rings etc.

He's bought a 2nd hand head which is ported with std exh cam, xe inlet cam. Was told it has 1mm oversized valves and solid lifters. He's shimmed the lifters himself (aparently) but when I went round the other day had a look at it before he bolted it up, measured the valves with a vernier and they're std.

Engine did about 500miles which he ran it in for but noticed a knock on light throttle once the revs are over about 2500rpm. Sounded really cranky so he took the crank out, sent it off to an engineering shop who said it was fine so refitted it with another set of new bearings etc. Anyway this ratttle is still there.

Again exactly the same, ONLY rattles about 2500rpm but as soon as any load or deceleration happens goes quiet. Engine sounds sweet as a nut all the other time but it does sound like a bottom end knock rather than a light tappet noise.

Question is has anyone heard of solid lifters causing this noise as we're starting to think although sounding like bottom end it must be something in the head as it didn't have any rattles / knocks before the rebuild.
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fennyLET · Posted: Wed Mar 03, 2010 5:16 pm Post subject:

With only reading the first 2 lines lol

Its the fact you have std cams. Ive been asking these questions over the last couple of days and when you fit solid lifters and double valve springs you can get away with useing std cams but it will rattle.
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Quote from PV "Your car could win....... if it rains"
Something along those lines anyway lmao lmao

John W · Posted: Wed Mar 03, 2010 5:25 pm Post subject:

lol, yeah bit long winded the post but wanted to try and explain what he's done.

Its on solid lifters but sure it had single valve springs. Don't know why its on solid's with the cam's he's got anyway tbh as he's not gonna be revving it hard, think its just as he bought it really.

Might tell him to change it back over to hydraulics then see what it does.

Cheers bud
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Full Circle of Evolution, Astra to Rover to Evo to Rover and back in an Astra

fennyLET · Posted: Wed Mar 03, 2010 5:42 pm Post subject:

And maybe sell me the solids ;)
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Quote from PV "Your car could win....... if it rains"
Something along those lines anyway lmao lmao

chip · Posted: Wed Mar 03, 2010 5:50 pm Post subject:

Solids normally make a noise at idle too, not just at one specific RPM, but maybe there is some sort of resonance happening.
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John W · Posted: Wed Mar 03, 2010 6:14 pm Post subject:

It's odd, can't understand why it only does it when there's no load on the engine. As said sounds sweet as a nut the rest of the time but when it does do it's quite a loud knock ie can be heard inside the car quite easily.

Suppose isn't really too much effort to swap the solids over see what it does, sure he's still got his old head lying around to rob the hydraulics out of.

fennyLET · Posted: Wed Mar 03, 2010 7:30 pm Post subject:

Let me know if he does. Inc make of them ect Thumbs Up

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Quote from PV "Your car could win....... if it rains"
Something along those lines anyway lmao lmao

GarySRi · Posted: Wed Mar 03, 2010 7:51 pm Post subject:

are the bottom end shells right for the crank?
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John W · Posted: Thu Mar 04, 2010 12:20 pm Post subject:

I did wonder about the shells as to me it does sound knocky but sure he would've used the right ones, suppose if we can't find anything on the top end it'll be next on the list to sort.

Spoke to him on the phone last night and apparently the noise has got worse on his way home from work, gonna pop over on sat and have a look with him see what its doing now but recon's its ticking at idle now too, suppose its gonna make it easier to listen to LOL

djbrowney let · vauxsport.com Joined: 27 Mar 2008 Posts: 931

it might be worth check worth checking oen journal on the crank isnt 0.5 mm undersize which isnt un common from vauxhall. gaz-d has had this a few times iirc Thumbs Up