That funny noise from under the hood. (1 Viewer)

[BigRed87]

Okay, been awhile since I posted, I have only got to put about 200 miles on my cruiser since September, since I live all of three blocks from my furthest class now.

The thing is I think that my clutch or something pretty close to it is F-in up. I have a pretty substantial knocking sound when the clutch is engaged and accelerating. So if I am going from a stand still to highway speed the knocking starts as soon as I get on the skinny pedal. Then once at speed it continues as long as I keep a steady foot. It gets louder and faster with increasing rpms and it stops when I let off the gas. (If I am driving around town it is usually just during acceleration from a stop, then is pretty quiet at steady speed up to about 45-50 mph, not gone, just quiet).

What do you oh might mudders think?

 

[BigRed87]

The latest pic I have of her, middle of nowhere (between Granbury & Cleburne, TX)

 

[2mbb]

Is it coming from the clutch or from the engine. Could it be pinging (pre-ignition). This could be caused by incorrect timing or bad (low octane) gas. What makes you think it is the clutch that is making the noise?

 

[BigRed87]

It doesn't make the noise in neutral, only when the gas is down and there is a load on the transmission. It did it even with a new tank of gas. I can rev it in neutral and it sounds fine. I thought that I might have got some mud or something in the clutch at first, but I wouldn't think it would have lasted as long as it has.

That is just what I think, I wanted to know of anything else it could be, so thanks. I'll check some more on that front. I'm not sure how the timing could have changed, nothing has been done to anything dealing with that.

 

[Heartworm]

Get your timing checked NOW! You can do it yourself. Either borrow or buy a timing light. The basic one costs about $30. If it is pinging, you will trash your engine.

 

[fliphkd778]

Mine recently doing something like this.
It could be an exhaust leak, when you load up the engine it makes itself noticeable. I highly doubt it is your engine pre-igniting or pinging if you haven't messed with the timing. The only other thing that keeps coming into my mind is the new 10% ethanol gas, maybe you got a higher dose of it?

 

[sl33py]

also check the egr tube. at the gasket mine was cracked - got pretty loud before i fixed it. not a knock so much as a ticking sound. Should be easy to find. Do you have a mechanics stethoscope to help locate any odd sounds?

rob

 

[BigRed87]

no stethoscope, I'll get the timing checked, and look at the egr. I did melt an egr bung over tthe summer, but the noise didn't start for another month or so.

 

[BigRed87]

sorry, got confused. I don't have an EGR... shhhh. I was thinking of the PCV bung that melted over the summer.

 

[lehiguy]

I hate to say it, but that sounds like the same symptoms as a rod knock, although you would be able to hear it in neutral as well... the higher the RPM the louder the knock.

 

[fliphkd778]

hmmm. good point. Pull the oil pan and feel your rods for movement.

 

[BigRed87]

Is there any other symptoms of rod knock?

Could my centerforce dual friction clutch have broken a finger or something?

 

[Pighead]

Sorry, you don't have fingers on your pressure plate anymore.
Pighead thinks either a bad exhaust leak, or rodknock.
Pray for the exhaust leak.

 

[BigRed87]

It would seem to me that if it were rod knock or an exhaust leak (which I know I had a little one a while back, which would make sense) that either of these would be just as prevelant when revving the engine at idle or would they only present themselves while the engine has a load on it?

 

[sdbrassfield]

U-Joints ... You did say near the clutch so it sounds like it may be back there somewhere, worth a check as it sounds like it continues w/ truck moving, not still. Maybe TO bearing never heard one do that though. They are usually noisy while sitting still w/ the clutch pushed in.

 

[wagon4wd]

If not preignition/detonation, I'd go with rod knock myself (how's the oil pressure). If the clutch is recent, I suppose it's possible that bolts didn't get tightened correctly, but this isn't as easy to check as
the other things already mentioned.

 

[hank14]

I wonder about the U-joints as well. Have you gotten under the truck (with the engine off, not parked on a hill in neutral with the parking brake disengaged, etc, etc) and checked for play in the driveshafts? Does it do this with and without the front hubs locked, in and out of 4WD?

Check these things out after you check the timing.

BTW- who says between Granbury and Cleburne is the middle of nowhere? Next time you're through this area, let me know.

 

[BigRed87]

I haven't had it in 4wd for a few months. there is a little play in the front drive shaft, but barely any in the rear. I guess I'll be checking the timing and maybe dropping the pan on Sunday, its raining and snowing at the moment.

 

[BigRed87]

haha, put less than 20 miles on her and she started spewing antifreeze and way too much steam out of the exhaust. i love sitting on the side of the highway waiting on a tow.

 

[Butt Ugly Chuck]

Ouch! Sorry man!
Butt