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AltaKnight
Jedi Knight
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Sure sounds like the rod bearings, I would be pulling the sump to check them out.
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KNOCK- KNOCK-KNOCK
- Thread starter DNK
- Start date
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AltaKnight
Jedi Knight
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Errrr, yeah!
swift6
Yoda
Offline
DNK said:tomshobby said:Well Don, you could start the engine and put the tranny in neutral. The push the pedal to the floor. The offending rod will present itself shortly.
Nothing happened ,now what
Which pedal did you push to the floor? I think Tom was encouraging you to floor the throttle pedal and expose the bad rod bearing by letting the engine self destruct. Which I believe was also suggested with tongue planted firmly in cheek. :wink:
philman
Jedi Knight
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I pulled the oil pan off my spare engine because I was hearing knocking noises like Don is. Everything looked fine there, and I replaced the oil pump gears and polished up the pressure relief plunger. But no help.
I ended up pulling the heads and discovering the previous builder reused the head bolts (including some short ones in the medium holes). Which would explain the cooling geysering out the overflow container after warm-up; and maybe the noises I was hearing were associated with supercharged coolant being forced through the cooling channels.
Heads are off to the machine shop to be resurfaced and pressure checked. New head bolts ordered. New head gaskets etc already in the shop.
I ended up pulling the heads and discovering the previous builder reused the head bolts (including some short ones in the medium holes). Which would explain the cooling geysering out the overflow container after warm-up; and maybe the noises I was hearing were associated with supercharged coolant being forced through the cooling channels.
Heads are off to the machine shop to be resurfaced and pressure checked. New head bolts ordered. New head gaskets etc already in the shop.
Got_All_4
Luke Skywalker
Offline
Try a quart of Marvel Mystery Oil. Add it to the existing oil and let the engine idle for a while. Then take it for a ride and just drive normal. If you have a sticking lifter it should free it up. Got lots of stories about that stuff that would take too long to write. It's made a believer out of me. I run it in all my cars. My 740 Turbo Volvo has 356k on it with the original turbo charger still working.
jessebogan
Jedi Knight
Offline
Try this, disconnect the plug leads one at a time, with the engine warm and making the noise. Even if you have to shut it off to remove and replace the leads. Run the car with each one off. If it is a rod bearing the noise should stop with the plug wire off. You can reconnect to confirm. Usually, when the combustion pressure is absent a rod bearing will quiet up. A lifter will continue ticking away no matter what. An added plus is that you positively identify the offending cylinder. Good luck.
R
RonMacPherson
Guest
Guest
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Jesse is on the right track. Checking the forum got in on page 2 and was surprised that no one had told you about this.
He's telling you an old field test. Pull each plug wire, one at a time. Use an insulated pair of pliers, or even plug wire pliers.
The noise may not go completely away, but the intensity and volume of the knock will lessen when you remove the combustion from the faulty bearing....
He's telling you an old field test. Pull each plug wire, one at a time. Use an insulated pair of pliers, or even plug wire pliers.
The noise may not go completely away, but the intensity and volume of the knock will lessen when you remove the combustion from the faulty bearing....
AweMan
Jedi Knight
Offline
I did mention the spark plug "Field test" {pulling the plug wires one at a time while the engine is at Op temp and running} in my post on page 1 of this thread. I guess no one was listening or I didn`t yell loud enough :lol:
Oh well, what do I know, i`m just a dumb welder!
Oh well, what do I know, i`m just a dumb welder!
AweMan
Jedi Knight
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Were it me I would remove the oil filter/canister { which ever the case may be} and drain it. It may take a couple of times and restarting the engine each time after you drain the filter doing it this way to get the amount you want out of the crankcase.
Or you could purchase one of those suction guns {any auto parts supplier has them} They look kind of like a grease gun only they are specificaly for sucking oil out of differentials, auto transmissions and the like. You will most likely have to purchase a longer hose if you decide to go this route tho.
Yea, I agree, if you remove the drain plug it`s gonna be a ALL situation, or quite messy if you try to replace the plug while it is still draning.
I think I would get the suction gun, you will find many uses for it over time.
P.S. once again a lifter noise is more of a tick tick tick where a rod noise is more of a knock knock knock!
the reason a rod knocks louder when warm is the rod journal expands with heat increasing the bearing clearance this is also the reason the oil pressure will drop off when warm even in a normal engine in reasonable condition. For instance my 460 ford with 64,000 miles cold oil pressure is 60 lbs at idle, at 180 degrees 40 lbs at idle at 190 degrees 30 lbs at idle after a long pull or hard work and at near 200 degrees it will drop off to 20 lbs at idle. Aside from new bearings A good quality oil cooler is the best present you could possibly give your internal engine bearings. Especialy if the bearings are already new or near new.
Just a dumb welders 2 cents worth.
Or you could purchase one of those suction guns {any auto parts supplier has them} They look kind of like a grease gun only they are specificaly for sucking oil out of differentials, auto transmissions and the like. You will most likely have to purchase a longer hose if you decide to go this route tho.
Yea, I agree, if you remove the drain plug it`s gonna be a ALL situation, or quite messy if you try to replace the plug while it is still draning.
I think I would get the suction gun, you will find many uses for it over time.
P.S. once again a lifter noise is more of a tick tick tick where a rod noise is more of a knock knock knock!
the reason a rod knocks louder when warm is the rod journal expands with heat increasing the bearing clearance this is also the reason the oil pressure will drop off when warm even in a normal engine in reasonable condition. For instance my 460 ford with 64,000 miles cold oil pressure is 60 lbs at idle, at 180 degrees 40 lbs at idle at 190 degrees 30 lbs at idle after a long pull or hard work and at near 200 degrees it will drop off to 20 lbs at idle. Aside from new bearings A good quality oil cooler is the best present you could possibly give your internal engine bearings. Especialy if the bearings are already new or near new.
Just a dumb welders 2 cents worth.
DK:
The audio kind of sounds a little high pitched for a rod knock, but could be my crappy speakers. Also, top end rpm is almost 2x as fast ast bottom end.
Do you have OP gauge? How is the PSI?
Also, did you try the broom stick to the ear at diff parts of the motor. You would be surprised as to how well that can isolate a noise.
Please, dont put the stick through your ear into your brain, it's not that bad!
Good luck.
The audio kind of sounds a little high pitched for a rod knock, but could be my crappy speakers. Also, top end rpm is almost 2x as fast ast bottom end.
Do you have OP gauge? How is the PSI?
Also, did you try the broom stick to the ear at diff parts of the motor. You would be surprised as to how well that can isolate a noise.
Please, dont put the stick through your ear into your brain, it's not that bad!
Good luck.