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Engine clacking at 4k rpm.

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Baz

Baz

Yoda
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Had a nice 2 hour drive with her yesterday, last couple of miles or so on the 4 lanes, I was doing mid/upper 60's mph.
Motor started clacking for a few seconds, instinct told me to relax the gas pedal, it continued doing it for another couple of seconds, then was fine.
Got it back up into the upper 60's (to replicate the conditions) and it did it again.
Oil pressure was OK, 60 ish throughout, 40 ish at idle with about 700-750rpm warm.
Timing 15* at 1000.
Lower rpms/mph all is fine and sounds great.
No new leaks, my 'control' oil leak was as normal as ever, 1 drip every 5 seconds when hot.

I'm wondering if this is related to my timing post a couple of days ago, this time with the added symptom of 'clacking' and what you all think.

It seemed to be more prevolent at constant, steady throttle, rather than on off.
Isn't it amazing how 1 drip of oil every five seconds is acceptable?
 
Sounds like a ping to me.
 
Check how much advance you have at 3200 rpm with the vacuum advance disconnected. If it is more than 30 degrees. then back it off.
Or... back it off a couple of degrees to the pinging goes away (like the old time shade tree mechanics used to do)

But... I'm not the best one to give advice in this area so you might wait on another opinion.
 
3200 roger, I'll get me light out. It's a dial type, so it should diagnose pretty good.
Thanks Trevor, gives me something to work off this morning.
 
Typically, you get ping or knock under load (going up a hill) or acceleration. Also, spark noise will generally stop as soon as you let off the pedal. But I would definitely check it out anyway, 'cause Trevor is pretty darn smart.

I would look around for something loose that might vibrate and bang against your frame, manifold, block, pipes etc. 4000rpm maybe the magic number that makes this object vibrate just enough to make a lot of noise. Perhaps a fuel filter or loose exhaust pipe?
 
Oh yeah, you can also pull your spark plugs and look for white flecks on the the electrode. That is the surest sign you are getting detonation. Running too lean can also cause detonation.
 
Morris said:
I would look around for something loose that might vibrate and bang against your frame, manifold, block, pipes etc.
Click to expand...
Kinda like the chrome strip on the passenger side that is now somewhere on IL Route 4? 67mph was the magic number to get that puppy slapping, well it's gone now.

Nonetheless, even after it went, I still get a pinging as Trevor nailed, which I will address, also a smell of hot engine oil, so something is going on....
 
Oh, does detonation cause the engine to run hotter? Not the coolant temp or anything like that, but the engine, around the head?
 
Yep
 
You have to have a lot of detonation to do some damage, that what we around here call spark knock. I always set the timing on my vehicles to where when you are in high gear and pulling a hill and have the pedal to the floor(the point where you should be gearing down) it will give a bit of spark knock. This lets you know that you are giving it more gas than it can use and are wasting fuel and need to back off or gear down. This gives max fuel economy. Trust me on this,I am a cheap bastard and have tried about everything. Timing set too high with a lot of spark knock will burn a hole in the piston as it is the weakest link in there. Your plugs will have aluminum on them as well. Baz, if you are not pulling on a hill and it does that at 4k on the highway as low geared as midgets are, I would think it is something else besides timing. I hate to say it but something might be lose inside like timing chain slap, etc. I would try all the obvious things first though, it might be something else simple.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] Baz, if you are not pulling on a hill and it does that at 4k on the highway as low geared as midgets are, I would think it is something else besides timing. I hate to say it but something might be lose inside like timing chain slap, etc. I would try all the obvious things first though, it might be something else simple. [/QUOTE]

My thoughts too. Is the valvetrain getting adequate oil delivery? Sounds like oil starvation to me, if it's an engine noise. Pressure in the galley can be good but if it isn't being delivered thru the rocker shaft properly you may get tappet noise at higher RPM. I'd double check rocker pedestals and shaft alignment.
 
If the noise stopped as soon as you released the throttle, then it is likely ignition related. I was reading your statement as though you were hearing it as you pushed the car into the upper 60's.

I dunno... the internet makes noises hard to trouble shoot. Heck, I have a bad squeak in my car that I have looked for years and still can not find. It sounds like a metal to metal squeak so eventually what ever is rubbing will break and should be easier to find. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Trevor Jessie said:
If the noise stopped as soon as you released the throttle, then it is likely ignition related. I was reading your statement as though you were hearing it as you pushed the car into the upper 60's.

I dunno... the internet makes noises hard to trouble shoot. Heck, I have a bad squeak in my car that I have looked for years and still can not find. It sounds like a metal to metal squeak so eventually what ever is rubbing will break and should be easier to find. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
Click to expand...
Trevor, one thing to check for that that was a hard one for me to find was the exhaust flange at the manifold. It has that donut gasket in it but the pipe to flange is metal to metal and would squeak more when hot but pretty regularly. I thought it was suspension becasue it sqeaked with a bump. I put a bit of nickel anti sieze on the inside of the flange and that stopped rhe sqeak.
 
regularman said:
Your plugs will have aluminum on them as well.
Click to expand...
"One of these things is not like the other"
Well, the plugs look OK to me, they are in order from right to left, 1 thru 4. #3 snapped as I was removing, making me get my emergency set of plugs.....Bosch Platinum. /bcforum/images/%%GRAEMLIN_URL%%/whistle.gif
Maybe I should just push the car from now on.

I stuck my nose in the oil filler cap, it's been 4 hours since I drove it, and considering it is relatively fresh (125 miles) oil, it stinks. Burnt.
What I could reach in that hole didn't have much oil on either, I'm out of Vv cover gaskets.

Would a youtube from the driveway help?

ab2d9272f15e3d261297ce4e75e3c2fc0_large.jpg
 
Just a thought (and some history) about detonation.

Those 125 miles or so are with new valves, hardened, 'fit for unleaded' stelite things. I put my 93 octane gas in it like I always have, but none of the lead substitute stuff, figuring the valves are equiped to deal with that.

Should I throw some of that in, see if it calms down?
 
Baz, detonation will sound similar to dieseling because that is what it really is, its preignition with the pistons firing before the spark. Do a youtube of the sound if you can and I will use my slow dialup and see if I can hear it. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif Do you have free long distance? I could probably tell over the phone. All 4 cylinders should be doing it and it should be quite a clatter.
 
You tube coming, whenever they get around to 'approving' it.
Just for S&G, I did a compression check, just to make sure that oil burning wasn't being consumed, and all those numbers check out OK.
Dry, between 120 and 130.
Wet, between 130 and 140.

Now Kim, the car doesn't diesel when I shut it off, but as you'll hear, it does sound like it....
 
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