Forged engine rattle thats concerning me

Luke.R

Luke.R

Member +
Hi guys, need a bit of help here. I have bought a forged engine last week and fitted it yesterday, now I'm a mechanic by trade so I know what im doing and Im using the correct oil, but Im getting quite concerned with the rattle it has, the engine is second hand and has done 5 - 6k miles according to the person I got it off, and he told be it had a bit of piston slap due to oversized pistons, so knowing this I did expect a slight noise till it was hot, but this noise is constant and I changes my cams and lifters over from my old engine and there was no difference. I changed the cams over because. I though it sounded a bit top endy, but after listening a bit closer it is coming from the bottom. now I have a video of it and wondered if anyone could let me know what they think?

http://www.youtube.com/watch?v=r1uepTF2JK4&feature=youtube_gdata_player
 
M

mork

Member +
If it's coming from the bottom then it'll be knackered shells I would guess. I don't know much about forged lumps, but I've read they rattle at the top end when idling, but that's not just rattle, sounds considerably worse than that. Drop the sump and take the bearings out, see if there's any damage. If not, at least you've eliminated the bearings/crank.
 
Luke.R

Luke.R

Member +
Cams are deffo tensioned as I always put a bolt through the service hole before removing. I know the cams are getting plenty of oil so I guess maybe do you reckon its worth checking the clearance between the shims and cam lobes?
 
sx_turbo

sx_turbo

Lifer
check the clearance on the shims, it doesnt sound like bottom end,

the rattling sounds normal, the loud ticking however sounds like and exhaust downpipe or manifold leak
check your manifold gaskets and for exhaust leaks, makes similar noise difficult when not physically there
 
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A

AdamB

Member +
sx_turbo said:
check the clearance on the shims, it doesnt sound like bottom end,

the rattling sounds normal, the loud ticking however sounds like and exhaust downpipe or manifold leak
check your manifold gaskets and for exhaust leaks, makes similar noise difficult when not physically there
Click to expand...

This mate, when you swapped over the cams did you swap over shims as well? It will be best to re-shim considering its a different engine.
 
Luke.R

Luke.R

Member +
I did swap my cams and lifters over and put them in as they came out, but then again it has had head work at some point so I will need to check the clearance anyway I guess. the tapping sounds worse in the video cos the phone is right up to the engine, to me it sounds top end too, but having a few more people say it too helps lol
 
Rob H

Rob H

Member +
It dont matter if you swap the lifters or not the valves them selfs wear too and if they have been recut that would make a difference too its all ways needed to check them once fitted. but it sure sounds like valve train noise to me!
 
sx_turbo

sx_turbo

Lifer
i recomend a 10w50, and some lucas oil stabilizer,

now i dont ever recomend additives in oil but i've seen this stuff in action and its the bolox, and makes even the rattliest of engines quiet, and it doesnt clog up filters or anything like slick 50 and stp does.


http://www.lucasoil.co.uk/products.php?page=products&subpage=product&product=12
http://www.lucasoil.co.uk/faq.php

i have personally used it and it does exactly what it says on the tin,

just thought i better add that the only reason i recomend this stuff is to reduce cold start wear and tear, not to mask inherent problems
 
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Luke.R

Luke.R

Member +
just checking at the moment and quite a few are really close, as in the min thickness on the feeler gauge wont fit inbetween the cam and shim. could that cause it?


thanks for all the help by the way guy :)
 
Texx

Texx

Super Moderator
A tight valve clearance is unlikely to cause a tap, it'd be more likely to cause a misfire if anything. However, if you have any valve clearance that's too tight they need to be dealt with or they will eventually cause some engine damage.
 
sx_turbo

sx_turbo

Lifer
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