Best way to reduce tappet noise?

dang

dang

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Has anyone had any luck quieting down the tappet noise on our M30's? I'm getting ready to put hood insulation on my car and wondered if any particular style works better than others to reduce noise. It should help keep the paint on the hood cooler if nothing else. :)
 
how bad is it? Have you compared your's w/another M30?

My M10 on my 2002 is pretty noisy. Adjusted the valves like 10x. Most likely a worn rocker arm.
 
It's a M30B35 from a '92 5-series. I've checked the clearance a couple times but not while hot. It's seems a bit noisier than normal. I haven't measured oil pressure but the light goes out within a couple seconds and I'm having trouble keeping the valve cover cap from leaking so I know it's getting oil.
 
I'm sure you've checked this since you have had the valve cover off, but when I went to adjust my valves, I found the center bolt that holds the oil tube had come undone which meant there was little or no oil squirting on the rockers. Valves were quieter after replacing that bolt and crush washer and adjusting the valves (I don't know which helped more)
 
Many of us do timing adjustments at the cam instead of the valve tip rocker arm.
It takes into account minor irregularities in the tips of valves.
I've been doing this for 10 years or more. Many others are now following this procedure.
I also run 20-50 as mentioned. I do live in warm climate. In cold climate use 10-40 in Winter.
Some don't like this idea but it does work well and eliminates noise.
Gary
 
m5bb said:
Many of us do timing adjustments at the cam instead of the valve tip rocker arm.
It takes into account minor irregularities in the tips of valves.
I've been doing this for 10 years or more. Many others are now following this procedure.
I also run 20-50 as mentioned. I do live in warm climate. In cold climate use 10-40 in Winter.
Some don't like this idea but it does work well and eliminates noise.
Gary
Click to expand...

So this just means you use the same technique but check the gap at the other end of the rocker?
 
There's a reduction you factor in so measured at the valve stem it's 25-30mm and measured at the cam it's 20-25mm- If I remember correctly. I got that info here, of course. I check both sides of the rocker now.
I've actually got the valve cover off and am investigating the exact same thing on my '92 b35. I found a slightly loose oil tube bolt yesterday so ordered new ones that come with the solid thread sealant.
 
TedS said:
There's a reduction you factor in so measured at the valve stem it's 25-30mm and measured at the cam it's 20-25mm
Click to expand...

I'm not following. I've always measured the gap between the top of the valve and the head of the rocker, and usually go about in the middle as far as the measurement. Something like .010 to .012in, I can't remember. Are you saying 0.20-0.30mm or are you measuring something else?
 
TedS said:
I'm sure @m5bb and others can explain it better but here's a link-
Click to expand...

Thanks for the link. Makes sense, I'll try it. The only thing I can add is the way I verify the cam is in the correct position is to put the cylinder in the 180deg firing order with the cam lobes teetering between the intake and exhaust lobes. Or in other words, if you're adjusting the #1 cylinder, have the #6 lobes at 11 and 1 o'clock. This guarantees the #1 is completely off the lobes. 1-5-3-6-2-4 ..... 1-6, 5-2, 3-4
 
reduction factor is 1.26 x less at the cam so if your target is .012 at valve it’s .095 at cam.

TedS said:
There's a reduction you factor in so measured at the valve stem it's 25-30mm and measured at the cam it's 20-25mm- If I remember correctly. I got that info here, of course. I check both sides of the rocker now.
I've actually got the valve cover off and am investigating the exact same thing on my '92 b35. I found a slightly loose oil tube bolt yesterday so ordered new ones that come with the solid thread sealant.
Click to expand...
 
A worn rocker is impossible to adjust correctly to one spec.
dependant on the exact position of the cam lobe to the rocker pad the delta of space between those parts changes according to the wear on the pad. That wear typically resembles either a ramp or scalloping. you can see five scallops or a big ramp on a worn rocker pad.
To check pad wear- set lash at .010, move cam 5 degrees and check again.
 
I'm embarrassed and happy at the same time. The noise that I thought was coming from the front of the head or timing chain area ended up being the water pump. The noise got worse so it was easier to find. Easy fix! New water pump on the way...
 
The banjo bolt issue Dick brought up is well known to the E24 world, I am suprised it does not come up here more. Is it a "everyone knows that" issue or is it not an issue on our cars? I was planning on getting new bolts but maybe just check and not bother?
 
bavbob said:
Is it a "everyone knows that" issue or is it not an issue on our cars?
Click to expand...
It's one of the first things I check when I get a new "old" BMW, along with valve clearance. Old school guys all know about it but there are a lot of newer generation owners that need to learn. Do we have a "First things to check when you buy an old BMW" list somewhere? I guess I should know that. :)
 
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