Timing Chain Noise

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dustermaniac

dustermaniac

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Just replaced the cam, lifters, pushrods, distributor and heads in my Duster. Everything has gone well in the tear down and assembly process. Old timing chain (Double Roller) had a bit of slack when removed. After I put in the new parts and rolled over the motor with a breaker bar, I can hear a small "clicking noise" sounds as if it is coming from the timing chain. The valves are all opening and closing when I roll over the motor by hand and the pushrods are all moving in tandem with the cam lobes. The noise seems to go away after I roll it over a couple turns. The camshaft is set at 0 on the timing marks. The chain was tight when I lined it up and installed the sprockets and chain. I am not sure if this is a major concern. I did use a straight edge after I installed the gears and chain and they look straight on the straight edge. Any assistance with this is appreciated, Thank You
 
Did you lube the chain or put it on dry? I put assembly lube on mine, some folks set them in oil for a bit before install. If you haven't put the cover on lube it up in good shape and lube the crank snout when you put the cover on so you don't have a dry start on the seal.
 
are the sprockets line up...the cam sprocket and crank sprocket might be binding the chain..
 
Does the chain seem to have slack in it?

I was talking to a friend of mine that works on motorcycles and he has had brand new chains stretch on him. The customer would bring the motorcycle back with in a short period of time. Takes the timing chain off and he throws it in the trash with low miles on the chain. I assume this could be true with automobile chains as well.
 
Chain was tight to the sprockets when installed. Old chain had quite a bit of slack when removed. I just went back outside and turned it over a few times again. I do not like the sound coming from the timing gear set. Set is a Comp Cams double roller timing chain. I will open it up tomorrow morning and try to figure out what the issue is. Timing marks are lined up within 1/8 " from top to bottom sprockets. I tried three times to get em perfect and this is as close as I can get. distributor rotor is pointing at #1 cylinder, on compression stroke. Everything seems to be lined up from what i can tell.
 
dustermaniac said:
Timing marks are lined up within 1/8 " from top to bottom sprockets. I tried three times to get em perfect and this is as close as I can get. .
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If they seem off, you should be able to rotate the engine a little one way or the other and they should line right up. Only time they won't line up is if they are actually off a tooth.

And, you don't actually go by the marks, but the teeth they are stamped on.
 
67Dart273 said:
If they seem off, you should be able to rotate the engine a little one way or the other and they should line right up. Only time they won't line up is if they are actually off a tooth.

And, you don't actually go by the marks, but the teeth they are stamped on.
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I did notice that when I rotated it just a CH that they would line up. I will pull the fuel pump tomorrow morning and see if this is the issue, if so what can I do to correct the problem?
 
grind the side of the pump arm a hair.

I always stick a magnet in the oil pan of engines i build, so if sht like this happens...i can catch as much as possible with the magnet in the sump.
 
Found the problem. Woodruff key on cam was the original I swapped out from the old cam. I should have known better when I inspected the key it looked worn. Well the key is so worn that it was barely able to turn the camshaft and get a good grip on the camshaft sprocket. Just ordered a new set from Summit and also a new thrust plate.I will replace both keys and the thrust plate So it will be at least another week before I will be able to get this job completed. I am not in a hurry, I'll just take my time and make sure that everything is right before I button it all up.
 
Yes the key was so thin on the sprocket, it was causing the sprocket to not "grab". The fuel pump was causing the sprocket to spin out of balance due to the pressure of the arm against the round flat cog that bolts to the sprocket. When I removed the upper gear, I could clearly see that the key was the issue. I will always remember to replace the key on any vehicle I change the timing gears on from this point forward. It was the key from the original cam. I didn't know there was a difference. I thought they were universal and just swapped it out from the old cam to the new.
 
1wild&crazyguy said:
pull the fuel pump out and see if you still hear the noise.

My double chains have always slightly rubbed the pump arm...bummer.
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the carter pump i had had a notched area on the arm i assume so a roller chain would work.
 
What the sound, sound like? When I turn my motor over makes a sound also kind of like a bike cain does. I dont know if its normal or how to check if its still good.
 
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