wierd sound in the engine after head installation

[grave77]

when I removed the head, I made sure not to remove the chain of its wheel. so I would position the camshaft on the same position again and dont hussle into the timing settings.

I installed the head, then turned the camshaft to fit the position of the chain wheel. bolted everything together and turned it on...

I turned it on and a fast and loud ticking was heared. engine wouldnt start too. fast is like the speed of the engine when it's running idles 4 ticks / second.

would the camshaft take 2 positions one is totaly off synch. or is the the oil pump jamed since there was water in the oil and car was off for more than 24 hours.

please advice..... thanks

[632 Regal]

oh god Barry... cant you line up some mars when at TDC? I sure hope you didnt bend all your valves but it's not sounding good.

[E34-520iSE]

I'm with Jeff here, you should have set it all up to TDC, and after completion, turned the crankshaft by hand with a spanner a couple of turns, just so you could "feel" for valvegear jamming, before using the starter. I suppose we all live and learn......just hope there's nothing broken :-(

Cheers,

Shaun

[grave77]

but I didnt turn the crank shaft after removing the head also I didnt remove the chain wheel so I assume that it was holding the camshafts position.

[Javier]

take it manually to TDC, and check camshaft alignment? What about clearance of parts, tools and similar to the moving parts of the engine like fan, pulleys, and so?

Sorry I don't buy the 24 hour standing with water in the pump, may be something is loose or misplaced around.


Javier

[pundit]

but I didnt turn the crank shaft after removing the head also I didnt remove the chain wheel so I assume that it was holding the camshafts position.
Unfortunately assuming something will be okay is not the way to go.
Valve timing is critical and needs to be checked to ensure it is correct prior to reassembly.
I would have the valve timing rechecked by someone who has some experience and then correct it if it is wrong. Then perfom a compression test.

If you haven't bent any valves then thank your lucky stars. If you have, then put it down to an expensive lesson!

[R1daveg]

In theory the cam position is the same as when it came off, so fingers crossed it will not have bent valves. Its good work practice tho to put it at TDC before u begin, and mark the sprocket/chain.

Couple of q's to clarify whats been done..
Did u dump all the old "milky" oil? As u indicate, it may be a case of no oil in the top end of motor. Manually oil can, wherever possible, you dont want it starting dry..
How did u ensure the chain is not moved at crank sprocket?

Turn it over by hand several times. You can then see if TDC and valve seem to be (sort - of) in sequence, feel if any resistance (bad), and start pump priming with oil.
You can also turn engine with starter and no plugs if confident of no mechanical problems, to prime the pump and not have the engine start dry.

[winfred]

that milk shake crap that oil turns into when mixed with water can clog the oil pump, seen it happen

[Kalevera]

The cam remains under spring tension via the rockers and can easily move with the head off/on the bench, so it's a good idea to reset the engine on TDC and turn it over by hand one or two times with the head reinstalled.

I run a new filter and a case of cheap oil through the motor for about 10 minutes before draining after doing a head gasket with oil contamination.

How old are the bottom end bearings? How long was the car run with the oil contamination?

Also, was the spring tensioner pretensioned? A worn guide or a slack chain would make a ticking noise, almost identifiable as bad valve clatter. Have a look at the procedure:

http://www.koalamotorsport.com/article-m30timingchaintensioner.asp

If I were you, I wouldn't try to start the car again until I'd pulled the head and checked the valves/set the engine to TDC. Here's why:

http://www.bimmer.info/~lowell/30s.jpg

That's 30 seconds of 3k rpm after dropping a valve.

best, whit

[grave77]

hummm ... well I feel better now since the engine didnt start, as I removed the spark plugs when I heared the sound. so it was only on starter.

the requency of the ticking was faster than the speed of the turning camshaft, I opened the valve cover to watch what was going on, I didnt see any hesitation in the camshaft rotation.

I also added the engine flush sort of oil as I wanted to run the engine for the 20 min before tensioning the head ( final 35NM stage )

chain tensioner was empty I tried to add some oil to bring on some tension but I think it was awaiting oil circulation.

it ran about a week with contaminated milky oil. but when I removed the valve cover oil seemed to be at the minimal contamination. especially at the top. I have no idea how was it down there.

I will check the TDC today while I was wondering about the camshaft. does a 360 rotation complete a full trip? 1 RPM = 360 degree on camshaft?

I didn't simply replace the gasket only, as I replaced the valves seals and basicly ported the head intakes; "Carbon build ups removal"

last question here, when the crank is set at O|T what should the valves look like which set of valves should be open and which should be closed. I think this would help me get things right and know whats going on.

Thanks Guys for your golden information.

[Bill R.]

cam gear is bigger than the crank gear.



hummm ... well I feel better now since the engine didnt start, as I removed the spark plugs when I heared the sound. so it was only on starter.

the requency of the ticking was faster than the speed of the turning camshaft, I opened the valve cover to watch what was going on, I didnt see any hesitation in the camshaft rotation.

I also added the engine flush sort of oil as I wanted to run the engine for the 20 min before tensioning the head ( final 35NM stage )

chain tensioner was empty I tried to add some oil to bring on some tension but I think it was awaiting oil circulation.

it ran about a week with contaminated milky oil. but when I removed the valve cover oil seemed to be at the minimal contamination. especially at the top. I have no idea how was it down there.

I will check the TDC today while I was wondering about the camshaft. does a 360 rotation complete a full trip? 1 RPM = 360 degree on camshaft?

I didn't simply replace the gasket only, as I replaced the valves seals and basicly ported the head intakes; "Carbon build ups removal"

last question here, when the crank is set at O|T what should the valves look like which set of valves should be open and which should be closed. I think this would help me get things right and know whats going on.

Thanks Guys for your golden information.

[grave77]

if it was clogged what would it do or sound like? how can I clean this up too?

[632 Regal]

crank spins 2 rotations and cam spins 1 rotation.

break out the yahoo and I can try to help you again.

[grave77]

I will join in when am home ... I will be glad Jeff ... you've done it before ... :)

I have digged in old threads in bimmer http://www.bimmer.info/forum/showthread.php?t=5403

there is cool stuff here about the TDC and other stuff too ..

I'm convinced that the TDC is off synch for sure ... 30 min and I will be off back home to complete what I started.

the only thing am worried about is replacing the valves cuz it was the toughest of all !! this valve pressing tool wasn't perfect.

still if I had to remove the head I will turn the engine without the head and see if I still have that damn sound.


One major question I had in mind, I was going to post a thread about it, is WHY WHY WHY the exhaust valves r smaller than intakes??

[grave77]

by the way ... this picture reminds me about my friends M20 325 engine .. he wanted to save 200Bux for a while so he postponed the timing belt replacement, for sure it cut off at 4500RPM and all the cylenders were broken, the best ones were like that picture, but most of them had the 2 valves hit and stuck in from the sides, engine was totally a piece of junk.

[632 Regal]

exhaust valves are smaller because the hot gas gets pushed out and the intake is pulled in which is harder to accomplish in a millisecond.

[Javier]

last question here, when the crank is set at O|T what should the valves look like which set of valves should be open and which should be closed. I think this would help me get things right and know whats going on.

Consider the following:

Distribution rotor (535i) will tell you which of the turns you are in, for cyl # 1, the top is ignition if rotor points to #1 spark plug, the next top is exhaust and rotor will point the opposite (2/1 turn radio Crank/Cam).

When # 1 is in ignition, both valves should be closed. Both valves should have been closed from about half turn of the crank shaft before top and will remain closed for about half turn after top.

The same will happen for the rest of the cylinders at 1/3 turn from TDC of the crankshaft in the firing order 1-5-3-6-2-4 (2 turns to complete de cycle).

This will tell you if you are about it, but will hardly reveal a 1 tooth misalignment on the sprockets.

Javier

[grave77]

well ... you were all right, TDC was offset ... around 40 degrees. I set it back right and engine rotates ok. I got the compression meter
tested all cylinders
and all preserved good compression ... aroind 9.5 with unbedded valves and no oil up yet.

bolted it then started it ... started like it was off 5 min ago. bolted the head stage 3 .... and then made oil chage and drove it a while .. I think I will need to adj the valves later on again. some ticking was loud. but its alright.

Thanks to you all ... without you guys it was impossible to finish the job.

here are some pics of the final look .. since I painted the manifold in black and installed the black cover I made.


http://divineftp.no-ip.org:1972/image_0007y8.jpg

http://divineftp.no-ip.org:1972/image_0007y9.jpg

http://divineftp.no-ip.org:1972/image_00077.jpg

[E34-520iSE]

That's great news! I'm really pleased you've got it running again. Now go and set those clacky valves up and check for oil leaks.;) Then have a well deserved beer!

Cheers,

Shaun

[Jon K]

so... did you confirm valves are not bent or did you just reset the timing and assume? Seriously, if the valves are in any way bent, replace them, or you'll be asking for serious damage aka terminal.

[Derek A.]

Your airflow meter is upside down. Do you have the bracket that bolts to the valve cover for it ?

[Jon K]

lol, i noticed that too. the rubber bushings are supposed to cushion it from the bottom... interesting lol.

[grave77]

well I will keep them ticking until next week ... at least they will be bedded right in. tho it was a good experience. and loads of wounds and scratches in my hands :P

[Jon K]

are you taling about the valve seats being bedded or the valve faces into the piston?

[grave77]

no I just said that when I placed the valves back in the head I didn't use grain paste to bed them so I assume that they need one week driving to have their positon right. thats when I will adj the valves again.

I was lucky that non of them were bent. or the compression meter would have shown that. all the 6 cylinders were preserving the same compression. around 145 PSI thats with the engine flush in ... still no oil. so if they were bent that read out would be impossible.