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Mordan
03-21-2009, 09:04 AM
Hey guys

I started the car fine. moved it outside for a hand wash. opened the hood and the valve cover. watched the valve clearance. no more clearance at the 6th exhaust valve. it is stuck and hard. seat valve need to redone. want to drive to the shop who repairs engines but when i start the car again I have this sound which i never had before even though my valve was already without clearance. this car won't move anymore and I will bring the cylinder head without showing them the head when still in the car.

but still curious to understand what makes this whining noise. thx for any input. it sounds like a belt but at the same time it comes from the head.

http://www.youtube.com/watch?v=fpuCKYhUn0M

Rus
03-21-2009, 09:17 AM
Water pump? Tensioner? Remove the belts and start the engine. If the noise goes away, its some component attached to the belt. If it stays, its engine-related.

whiskychaser
03-21-2009, 09:24 AM
Sounds like a bearing 'picking up'-you can get that sort of squealing noise if the outer race of the bearing is turning in the housing instead of staying put.

Mordan
03-21-2009, 10:30 AM
Water pump? Tensioner? Remove the belts and start the engine. If the noise goes away, its some component attached to the belt. If it stays, its engine-related.

i did it. and still the noise :(

it is engine related ... or maybe I thought an air leak lol? you know if the exhaust valve is broken or not fully seated you would have air going through a small opening...

Mordan
03-21-2009, 10:32 AM
Sounds like a bearing 'picking up'-you can get that sort of squealing noise if the outer race of the bearing is turning in the housing instead of staying put.

sorry I don't follow you. which bearing are you talking about? Is there a rationale for it going bad after a hand wash of the car and my valve train problem?

whiskychaser
03-21-2009, 11:49 AM
sorry I don't follow you. which bearing are you talking about? Is there a rationale for it going bad after a hand wash of the car and my valve train problem?
My first thought was cam bearing because of the problems you have had though of course they dont have any shells that could move. It could also be the belt tensioner or rollers. Noise is a hell of a job to nail down, especially by remote:-)

E34-520iSE
03-21-2009, 12:49 PM
That sounds vile. Did you check all the rocker clearances then? Is the oil spraybar working? Sounds like it's going to granade if you run it much longer.

Regards,

Shaun M

Blitzkrieg Bob
03-21-2009, 02:26 PM
Do you have a really long screw driver or rod?

Find one or get a mechanic's stethoscope (even cheapo ones are good to have)

Poke around the motor to locate the noise, just rest the tip of the screw driver or rod against the suspect part and press it to your ear. It will become very apparent what is failing.

632 Regal
03-21-2009, 04:46 PM
Eyuuuk!

Pull the valve cover off, from the sound of it something will be pretty obviously fubarred. The sound does seem to be the mid to rear area of the head. If you had a bent valve you would have excess clearance not zero clearance. Sounds like somethings starving for oil.


Hey guys

I started the car fine. moved it outside for a hand wash. opened the hood and the valve cover. watched the valve clearance. no more clearance at the 6th exhaust valve. it is stuck and hard. seat valve need to redone. want to drive to the shop who repairs engines but when i start the car again I have this sound which i never had before even though my valve was already without clearance. this car won't move anymore and I will bring the cylinder head without showing them the head when still in the car.

but still curious to understand what makes this whining noise. thx for any input. it sounds like a belt but at the same time it comes from the head.

http://www.youtube.com/watch?v=fpuCKYhUn0M

Mordan
03-22-2009, 02:45 PM
Eyuuuk!

Pull the valve cover off, from the sound of it something will be pretty obviously fubarred. The sound does seem to be the mid to rear area of the head. If you had a bent valve you would have excess clearance not zero clearance. Sounds like somethings starving for oil.

@blitz. i did use a stetoscope and man the noise was so loud and strident it didn't make any difference.

i did pull the cover off afterwards and everything seemed 'normal'
starving for oil yea. this scares me everytime I open the cover off that something falls in the oil passage. I'm 99% positive nothing fell. But for the sake of the exercise. what would happen if a nut/a bee/ a twig, fall into one of the oil passage. what happen next? will it be pumped by the oil pump to the oil filter and then the the cylinder head passages?

E34-520iSE
03-22-2009, 03:23 PM
Loose bits of engine usually end up in the sump. Any chance of a good photo showing the cam gear?

Shaun M

Mordan
03-22-2009, 03:25 PM
Loose

??? I loose the engine? yeah! time for a full rebuild! :D

632 Regal
03-22-2009, 03:36 PM
Oil passage? are you referring to where the oil drains back into the pan? Not much would happen there however if something fell into the pressurized passage say at the cam journal would cause oil starvation. If something fell into the oil filter housing on the wrong side it would be pumped right into oil passages blocking the pressure. Oil from the pan goes to the pump, then to the filter housing, through the filter and then direct to where it needs to go to keep everything from sounding like your video.



this scares me everytime I open the cover off that something falls in the oil passage. I'm 99% positive nothing fell. But for the sake of the exercise. what would happen if a nut/a bee/ a twig, fall into one of the oil passage. what happen next? will it be pumped by the oil pump to the oil filter and then the the cylinder head passages?

whiskychaser
03-22-2009, 03:47 PM
@blitz. i did use a stetoscope and man the noise was so loud and strident it didn't make any difference.

i did pull the cover off afterwards and everything seemed 'normal'
starving for oil yea. this scares me everytime I open the cover off that something falls in the oil passage. I'm 99% positive nothing fell. But for the sake of the exercise. what would happen if a nut/a bee/ a twig, fall into one of the oil passage. what happen next? will it be pumped by the oil pump to the oil filter and then the the cylinder head passages?

Oil coming up to the top of the engine is under pressure so there is nowhere a foreign object could get in. It drains back to the sump under gravity where the filter would catch anything. I dont know the M20 that well but I think it has a feed pipe to lubricate the cam faces? If there is no oil coming out of the little holes when you crank it, there is a serious oil feed problem somewhere

Mordan
03-22-2009, 05:40 PM
yea I know about this feed pipe. I will check it. anyways the car won't move anymore and I will get the head out and check everything.

@regal. those passages back to the sump. I'm glad to hear it would go to the filter. for the cam oiling, I will check the passages once the head is out.

632 Regal
03-22-2009, 06:55 PM
Take pictures, lots of them. Its like automotive porn :D


yea I know about this feed pipe. I will check it. anyways the car won't move anymore and I will get the head out and check everything.

@regal. those passages back to the sump. I'm glad to hear it would go to the filter. for the cam oiling, I will check the passages once the head is out.

russiankid
03-22-2009, 07:17 PM
Sounds like the tensioner on the timing belt is on its very very last leg.

632 Regal
03-22-2009, 07:33 PM
yes check into that when you get the head off.

Sounds like the tensioner on the timing belt is on its very very last leg.

Blitzkrieg Bob
03-22-2009, 10:35 PM
@blitz. i did use a stetoscope and man the noise was so loud and strident it didn't make any difference.

Did you use a mechanic's Stethoscope? The doctor type will make your ears bleed on an engine.

Morgenster
03-25-2009, 07:04 AM
Eyuuuk!

Pull the valve cover off, from the sound of it something will be pretty obviously fubarred. The sound does seem to be the mid to rear area of the head. If you had a bent valve you would have excess clearance not zero clearance. Sounds like somethings starving for oil.

Eeuw! I concur! That really sounds like metal scraping on metal really fast. Something has lost lube entirely and is not going to last much longer.