engine knock/rattle 360
- Thread starter Val360
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An older thread does not mean it is invalid.... "Stickies !"
So I adjusted my valves..allwere fine... And started engine...I could feel a sharp knock while my hand was on the carb ! It was not a consitant "knock.knock.knock" it was more of a "knock....knock....knock..." Not sure if you can picture that ! Lol
I am thinking piston pin...
This was at idle.. And The engine seems to be running rough. More shaking than just a lumpy cam !
Any thoughts ?
So I adjusted my valves..allwere fine... And started engine...I could feel a sharp knock while my hand was on the carb ! It was not a consitant "knock.knock.knock" it was more of a "knock....knock....knock..." Not sure if you can picture that ! Lol
I am thinking piston pin...
This was at idle.. And The engine seems to be running rough. More shaking than just a lumpy cam !
Any thoughts ?
GEO
Sarcasm Inc.
I'd start with basic's try disconnecting the plug wires one by one and see if one or more of them makes no difference at all.
Mad Dart
Nothing to see Here!
Lol.
Was watching your video again.
I just figured it out. YOUR MASTER CYLINDER, IS ON THE WRONG SIDE!
No Seriously, i thing it is a eng Knock as in ping from one cyl having way to much timing( wires crossed) and the next cyl not fire because it is firing after top dead center. aka to late!
If you will fallow GEO advice and pull one plug at a time. And you find one that has no affect and one that stops the knock.........Well you will be on the road to recovery.
I just figured it out. YOUR MASTER CYLINDER, IS ON THE WRONG SIDE!
No Seriously, i thing it is a eng Knock as in ping from one cyl having way to much timing( wires crossed) and the next cyl not fire because it is firing after top dead center. aka to late!
If you will fallow GEO advice and pull one plug at a time. And you find one that has no affect and one that stops the knock.........Well you will be on the road to recovery.
I checked my firing order twice but will do it again. If that is it i would be jacked!
But I doubt it since it ran ok (not perfect ) before .
I thought the exhaust sound like it was running rich , not quite crsp , so I started playing with the jetting and swapping carbs....that is when the noise started becoming prominent.
It could be that I leaned out the jetting too much or that the over rich jetting masked the
Detonation ?
I am not really sure what this car should sound like since everything is new ?
But I doubt it since it ran ok (not perfect ) before .
I thought the exhaust sound like it was running rich , not quite crsp , so I started playing with the jetting and swapping carbs....that is when the noise started becoming prominent.
It could be that I leaned out the jetting too much or that the over rich jetting masked the
Detonation ?
I am not really sure what this car should sound like since everything is new ?
Yeah that's what i realized after mad dart comments and i re read the hole thread:violent1:
To bad you can't have a video for yours.
They say a picture is worth a 1000 word,..... a video would be priceless. :smile:
I can do a vid but I doubt you will here the knock.
I have been focusing on trim and weatherstrip installs today.
I figure if it not going to run right...might as well look good ! Lol
And maybe if I step back from the motor issue I can clear my head and attack it
Tomorrow focusing on the basics and working forward. I feel I may be overthinking
The problem ! You know the paranoia you get on a fresh build and start.....
I am trying to get this on the road by next Saturday because my son " Cuda " wants to take it to prom.
I have been focusing on trim and weatherstrip installs today.
I figure if it not going to run right...might as well look good ! Lol
And maybe if I step back from the motor issue I can clear my head and attack it
Tomorrow focusing on the basics and working forward. I feel I may be overthinking
The problem ! You know the paranoia you get on a fresh build and start.....
I am trying to get this on the road by next Saturday because my son " Cuda " wants to take it to prom.
GEO
Sarcasm Inc.
Re wired plugs again. Still making knock. It is strange because it knocks every 2-5 seconds.... No rythem at all ! Just every so often... It is not at crank or cam speed.
Sounds like there is a little man under my manifold..lol...whacking with a tiny ball pean hammer at random.....
I will try pulling plugs to isolate cylander tommorow...too late for neighbors tonight.
Sounds like there is a little man under my manifold..lol...whacking with a tiny ball pean hammer at random.....
I will try pulling plugs to isolate cylander tommorow...too late for neighbors tonight.
Took belts off and it is still there.
It is a double knock.. Knock knock...........knock knock............knock knock.... A sharp metallic sound... Like whacking an aluminum intake with a small hammer.. Now that I think about it. It sounds like the click my torque wrench makes .....only louder !
I am thinking wrist pin ...?
It is a double knock.. Knock knock...........knock knock............knock knock.... A sharp metallic sound... Like whacking an aluminum intake with a small hammer.. Now that I think about it. It sounds like the click my torque wrench makes .....only louder !
I am thinking wrist pin ...?
GEO
Sarcasm Inc.
You have pulled the valve covers and looked for a broken rocker arm or push rod?
Yes... Valvetrain is good and silky smooth... I stuck my stethescope in the valvecover holes.
I am pretty sure it is a wristpin from all the research I have done.
This is a new motor..would you figure a defective part or error by machinist ?
I am pretty sure it is a wristpin from all the research I have done.
This is a new motor..would you figure a defective part or error by machinist ?
GEO
Sarcasm Inc.
I've taken apart engines where the pin retainer has broken and let the pin scratch the cylinder.
Might drain the oil in a paint strainer and see if it has any metal in it
Val 360
I had the same problem with my freshly built engine. And by the sounds of it the same specs. First time I started it it wasn't there. We did a tune and then decided to scrap the old carb and distributor. Second time around the same knock as yours began.
It turned out that three of the pulley bolts that sit around the crank bolt were gone. This was due to a couple of things I did wrong. 1. No lock tight on those bolts 2. I cheated and used a impact wrench on those bolts instead of hand tightening them 3. The engine mount bolts needed to be tighter. I had about a inch lift on it when we discovered the problem. Now that those bolts are back in and TIGHT there is no knock.
See how it goes, I'd bee interested to see if this helps.
Cheers.
I had the same problem with my freshly built engine. And by the sounds of it the same specs. First time I started it it wasn't there. We did a tune and then decided to scrap the old carb and distributor. Second time around the same knock as yours began.
It turned out that three of the pulley bolts that sit around the crank bolt were gone. This was due to a couple of things I did wrong. 1. No lock tight on those bolts 2. I cheated and used a impact wrench on those bolts instead of hand tightening them 3. The engine mount bolts needed to be tighter. I had about a inch lift on it when we discovered the problem. Now that those bolts are back in and TIGHT there is no knock.
See how it goes, I'd bee interested to see if this helps.
Cheers.
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