High compression timing issue.

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fredsmedina said:
Forgot to add that the factory specs for this motor say34 degrees at 3500 RPM. Not sure exactly what that means though. I may be slightly ignorant when it comes to timing
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It's specs say "10:1" with cast iron heads? Do you have any specs on the cam in the motor?

With a loud exhaust, bigger cam, and/or vehicle with interior noise, you may not be hearing the knocking while driving.

So have you ever checked to adjusted the timing on a vehicle? You need to buy a timing light and learn how to check timing. Unless you have a shop you want to pay to have it checked and tuned every 1-2 years. That is modified motor that will need more attention.

Never trust used older vehicles like that. Immediately take drums off and inspect brakes, lube chassis and inspect for wear, get under car and inspect everything, pull spark plugs, check cap/rotor, check timing, check voltage. Assume nothing.

A vehicle like that truck is not going to be perfect. And I'm sure you didn't pay perfect condition price for it. So it's just about being aware of what is going on.
 
I have to agree, that one deep knock sounds like its coming from down under. If it was mine I'd pull the pan too. I've heard that knock a few times, and it was always in the bottom.
 
So I pulled the transmisio . Realizing that the previous owner didnt take care of the vehicle..

2 of the 5 bellhousing bolts were missing. 2 were slightly loose already. And only 1 tight..

As far as the flexplate goes, 3 of the 4 bolts that hold flexplate to the torque converter were already loose when I went to pull them...

I feel like an idiot for not going through everythingwhen I purchased the truck... lesson learned though!

I also discovered the source of a transmissio fluid leak. There were 2 repairs in the trans lines that were done with rubber fuel lines and hose clamps...

So ive got a few repairs to do. This was also my first transmission removal, so it took me 6-7 hours just to drop it out. Went pretty smoothly though. .


Ive attached a photo of the flex plate still attached to the motor. Do the fluid streaks coming from where the bolts were attached to the converter mean anything?

Once I address my obvious trans issues I will fire her back up and see where we stand.. also, discovered ome faulty spark plug wire on cylinder 3. Could this have been causing any of the knocking? The wire didnt have a solid connection to the spark plug. It Looked bent, and fit loosely over spark plug...

Thanks for all the help!
 

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Right at the end of the video you revved the engine and I heard it pop back through the intake. That's a sure sign of a valve train issue. Even though you found issues with the transmission I'd check under the V covers real good.
 
Ill be pullin the valve covers in the AM. what am I looking for besides obvious sludge, metal shavings, etc..? Anything in particular to check for?
 
autoxcuda said:
It's specs say "10:1" with cast iron heads? Do you have any specs on the cam in the motor?

With a loud exhaust, bigger cam, and/or vehicle with interior noise, you may not be hearing the knocking while driving.
Click to expand...
Will update when I pull covers tomorrow. Here are cam specs for

Cam Type: Flat Tappet
.545 Intake .545 Exhaust
241 Intake / 247 Exhaust duration
@ .050 - 110 degree lobe separation
 
First things to see are bent pushrods and/or loose rocker bolts, also check cam lobes and lifters for excessive wear.

Congrats on finding those issues it's a relief to catch something like that before it turns into something far worse (cracked bellhousing for one!).
 
Roll the engine over when checking for excessive slop. If the cam lobe on the valve your checking is on the high side you may not be able to feel a problem. And see if you can push any valves down by hand which would indicate a weak or broken valve spring
 
[ame]https://youtu.be/BkfjhAiGOIc[/ame]

This rocker arm is very loose. Is this normal? Appears to be exactly where I was hearing the noise from. I haven't rotated engine yet to see if the 'slop' may be due to the position of the cam, or loose lifters, etc...

I still have some research to do about what else may be wrong. I will have a couple hours to work on it again tomorrow and ill be double checking the valve spring on that last cylinder.

Any thoughts based on my latest video?
 
That's definitely not right and most likely what you were hearing. Kinda appears to be a collapsed lifter since you can push it down and it springs back up. If it's a flat tappet cam you might be able to unbolt the rocker arm and remove it and the pushrod and use a long magnet tool to fish the lifter out for inspection. if it's a roller cam you'll have to pull the intake to inspect it further
 
I think there will be more, judging by the earlier video. But the others will not be as bad . I only heard the one seriously loose one. But I heard lots of others clattering/clacking.
 
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