Loud Tapping From Head (mi16)

[choco 0]

Hi, sorry to disturb you wisemen on this lovely sunday morning...

I changed my headgasket after it started leaking (lots of white smoke, and coolant loss and under pressure) I had the head skimmed and valves cleaned and checked, they were all ok. Then i put the whole lot together again. I have a homemade vernier on the inlet-cam, and no timinghole or markings. So put on the one from the exh. cam, and copied it's position. Not perfekt, but it can't be more than half a tooth out. This can't be enough for piston-meets-valve, can it? But when i started the car for the first time, it had a loud tapping noise, coming from the cambeltside, nr 3 or 4 cilinder, not sure. After extensive searching on this website of wisdom, i found out that it maybe can be a tappet? Forgot to fill these up with oil, how long will it take the engine to do so, and can that be the source of this sound? If it is a sticky tappet, can i spot that one with just the headcover off, and turning the crank?

 

Cheers,

 

Johnny

[sport1901966 8]

I can't comment on the piston meeting valve question, but it does take a good few minutes for the lifters to fill up and quieten down in the region of 5-10 I think when I first started my rebuilt Mi.

 

Did you try turning the engine over by hand before starting it on the starter?

 

I would imagine it would be pretty difficult to spot a sticky lifter when turning by hand but it may well be possible....I've never tried!

 

Good Luck

[choco 0]

Yes i did turn it over once by hand, seemed fine. Is the tapping noise really loud if the're not filled up yet? And shouldn't they all make a sound, it only comes from the cambelt side on mine?

[johny105_y2k 1]

you could of blocked an oil gallery with the HG. or it could be a blocked spray bar on the cam top. maybe.....?

[woodsy 0]

did you put the spray bar right way round.The side with holes in goes on the inlet cam as the exhaust is cam is covered in oil as due to the angle of engine

[jerseypug 1]

did you rotate either cam on its own as the the valves on the cam you are turning will hit the open valves on the other cam and bend them. Ive got the tshirt for that one

[floodys 4 1 Cars]

i know you said you checked valves but i had 2 bent valves, so slight that when fully seated it didnt let any air through, i.e tested this by pressurising chamber with airline, i had to take head off and pulled all valve out ot find a in and ex very slightly bent, runs like a dream now and quiet!! still with bent valve was doing sub 10 min laps at the ring and averagein 30mpg!!

[choco 0]

The valves were checked by a pro (could also tell from his bill ) I did rotate the cams on their own, but only if the other one was locked with the timinghole. Guess i have to live with it for now, don't have the money or the time to do a head off job again..

[welshpug 1,657]

but do you have the money to repair it when a valve head drops off?

[porter_bmx 0]

may sound silly but i had this problem, then reliased it was the top engine mount. try pull back on the mount to see if it stops it. i had group N rubbers on it and was causing tapping noise due to vibrations whiped off the mount took a mm or two of the rubber now no sound at all. mine sounded like the cam side as well. just a thought.

[choco 0]

but do you have the money to repair it when a valve head drops off?

 

My problem is that i'm visiting my parents in Holland right now, and have to start work thursday in Denmark. A 850km trip, so i have to take the risk...

Checked my mount, that's not it.

[taylorspug 7]

Other things to try before you whip the head off:

 

Loose spark plug or leaking exhaust manifold gasket.

[porter_bmx 0]

ah ok then. i was a day away from a rebuild when i noticed lol thank god i lent on the mount. hope you get it sorted matey

[jerseypug 1]

The valves were checked by a pro (could also tell from his bill ) I did rotate the cams on their own, but only if the other one was locked with the timinghole. Guess i have to live with it for now, don't have the money or the time to do a head off job again..

 

100% bent valve. when one cam is locked, 2 valves are open enough for the opening valves to hit. when i took mine apart you could not tell the valves were bent, only by rotating them in the head with a suction stick for lapping. i was in denial replacing all the buckets and both cams as i did not want to take the head off again. as it happens, when i refitted the head with the new valves, i left some paper towel in the inlet manifold that got sucked into the engine on start up bending another 2 valves. you have to laugh. it was worth it as the mi is a lovely underrated engine and goes like stink when working properly.

good luck

[choco 0]

Found the problem, the timing was all wrong. One of the tensioners moved causing slack on the cambelt. Hope i didn't damage it too much, have to drive in a couple of hours. But it sounds a lot better again. Thank you all for the input!