nasty noise on my new v8

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spratty
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nasty noise on my new v8

Post by spratty »

I've just swapped the 3.9 v8 in my discovery to cure a noise i thought was a slipped liner. turns out it wasn't slipped at all, but that's a different story.

the engine that's gone in came from a friend who removed it to fit a 4.6, it had no noises when it was in his car.

the parts i had to swap over from my engine:
rocker assemblies
rocker covers
push rods
distributor
inlet manifold/plenum
power steering pump/air con/alternator.

on starting it for the first time i had the usual tappet noises which died away fairly quickly, but a different noise remained which i think may be quite serious.
i have a video of it on youtube:
http://youtu.be/avoieTD1wCc

what could the noise be?
have i fitted the rocker assemblies wrong?

the ignition timing isn't set properly yet, could that be it?
it starts very easily and idles much better than the old engine.

thanks
Ian


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Post by kiwicar »

Hi
I wiould check the exhaust manifolds for leaks, a common sourse of nasty metalic sounding noises, especially if the timing is a bit retarded. then check you put 20/50 in it and not something thin and watery. leftany spanners on the lifter valley?
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Mike
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ChrisJC
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Post by ChrisJC »

I think I'd remove the fan-belt(s) and try it for 20 secs to see if the noise goes away.

Oil pressure OK?

Chris.
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paul c
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Post by paul c »

The squeeling sound sounded like it could be a flex plate problem, is it an auto? The knocking is a bit harder to pick out until the squeeling is sorted.
spratty
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Post by spratty »

thanks guys
its not a squealing sound, its whistling in the air intake. i think the LPG venturi makes most of the noise.

i had thought about taking the fan belt, but not got round to it yet.

Ian
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Post by scotb »

loose flywheel bolts? did you loctite them? 8)
mgbv8
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Post by mgbv8 »

paul c wrote:The squeeling sound sounded like it could be a flex plate problem, is it an auto? The knocking is a bit harder to pick out until the squeeling is sorted.
Thats an interesting comment Paul?? Why would a flex plate make a noise like that?? Mine recently made a grinding noise. But that was because I broke the hub out of the flex plate :shock:
Perry Stephenson
MGB GT + Rover V8
9.62 @ 137.37mph
Now looking for 8 seconds with a SBC engine
http://www.youtube.com/watch?v=nVscbPHgue0&list=UUqIlXfSAoiZ--GyG4tfRrjw

https://www.youtube.com/watch?v=eg3avnsNKrc&index=2&list=FLqIlXfSAoiZ--GyG4tfRrjw
mgbv8
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Post by mgbv8 »

spratty wrote:thanks guys
its not a squealing sound, its whistling in the air intake. i think the LPG venturi makes most of the noise.

i had thought about taking the fan belt, but not got round to it yet.

Ian
Where do you live Ian ??

Maybe one of us could pop round for a listen !

Perry
Perry Stephenson
MGB GT + Rover V8
9.62 @ 137.37mph
Now looking for 8 seconds with a SBC engine
http://www.youtube.com/watch?v=nVscbPHgue0&list=UUqIlXfSAoiZ--GyG4tfRrjw

https://www.youtube.com/watch?v=eg3avnsNKrc&index=2&list=FLqIlXfSAoiZ--GyG4tfRrjw
paul c
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Post by paul c »

mgbv8 wrote:
paul c wrote:The squeeling sound sounded like it could be a flex plate problem, is it an auto? The knocking is a bit harder to pick out until the squeeling is sorted.
Thats an interesting comment Paul?? Why would a flex plate make a noise like that?? Mine recently made a grinding noise. But that was because I broke the hub out of the flex plate :shock:
I had a noise like that from one, think I may have left the converter bolts out once, was a long time ago.


EDIT... I remember now, it was the torque converter had come forward and jumped off the splines as the trans was put in, was all tight when it was bolted up but didnt realise why until I started it.
Last edited by paul c on Wed Oct 03, 2012 9:24 am, edited 1 time in total.
stevieturbo
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Post by stevieturbo »

That is a serious metal-metal contact there, not a minor issue.

And it doesnt sound like anything top end or valvetrain related.

It could be in the bellhousing area somewhere as some have suggested

And a slipper liner wouldnt make a noise. The fact you seem to suggest the noise is there with two engines in the same vehicle though would start pointing somewhere other than the engine.

Removing the fan belt would rule out external rotating parts though. But it just doesnt some like any of that
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spratty
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Post by spratty »

the sound i'm worried about with the new engine wasn't there with the old one, so it's either something i disturbed when swapping it over, or something I've done wrong.

it is an auto, and as far as i can tell the torque converter didn't move at all when i removed the old engine. yes the flywheel bolts were loctited and torqued, but i cant remember what i used (it was a while ago that i started the swap) i know i looked the settings up, and had to buy the right loctite gloop.
if the TC had disengaged slightly, and is now back on wrong, i would have assumed that either the engine wouldn't bolt home to the bell housing easily, and also that i wouldn't be able to drive it, neither of which is true.

i live in the Medway towns, in Kent

Ian
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Post by jetskijase »

i had something a little similar, turned out to be the splash guards inside the rocker covers catching on rockers, noise increases when revved, worth a quick check by whipping covers off
rover v8 into a robin hood.....thats the plan anyway!. update, its in and runs!! but will it stay cool??? will the bonnet fit??? will the clutch cylinder work???? who cares it sounds awesome!!!!!!!!
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ChrisJC
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Post by ChrisJC »

Strictly speaking, you are supposed to measure torque converter depth, and shim the flexplate assembly to get the right amount of clearance between torque converter and gearbox input gubbins.

Chris.
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Series IIA 4.6 V8
R/R P38 4.6 V8
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