Somebody's knockin........

[redfishsc]

Update. Might be a bad cam lobe. Haven't pulled the cover yet but probably will soon.

I discovered the knock sensor code was thrown (low voltage) and discovered that the connector had come loose. I plugged it back in and the code didn't come back after a 10 minute idle.

That doesn't change the knock sound, I think it's just a coincidence. Maybe.


So here's what I have discovered about the knock

• Knocks at half the engine speed (326 knocks/min at idle, idle speed about 665 rpm according to OBD2, ).
• Pulling plug wires, did not make change to sound.
• Using long screwdriver, I can isolate the sound to the rear of the engine near the rear main but I cannot tell if it's bottom end or top end. Sorta sounds "central".
• Revving engine makes it louder.
• Sometimes the knock disappears then comes back when idling.
• Knock does not change when shifted into park, reverse, or drive.

I'll look into what it takes to do a cam swap.


I'm also wondering if perhaps this is flex plate or something in the bell housing. I've crawled under it while running and can hear the sound just as well down there, but the sound is hard to isolate. It's definitely at the rear of the engine but hard to say if it's inside the motor or in Bellhousing

 

[letitsnow]

How did you deal with the P/S pump? .

I unbolted from the motor and let it sit on the frame rail.

 

[SAATR]

Update. Might be a bad cam lobe. Haven't pulled the cover yet but probably will soon.

I discovered the knock sensor code was thrown (low voltage) and discovered that the connector had come loose. I plugged it back in and the code didn't come back after a 10 minute idle.

That doesn't change the knock sound, I think it's just a coincidence. Maybe.


So here's what I have discovered about the knock

• Knocks at half the engine speed (326 knocks/min at idle, idle speed about 665 rpm according to OBD2, ).
• Pulling plug wires, did not make change to sound.
• Using long screwdriver, I can isolate the sound to the rear of the engine near the rear main but I cannot tell if it's bottom end or top end. Sorta sounds "central".
• Revving engine makes it louder.
• Sometimes the knock disappears then comes back when idling.
• Knock does not change when shifted into park, reverse, or drive.

I'll look into what it takes to do a cam swap.


I'm also wondering if perhaps this is flex plate or something in the bell housing. I've crawled under it while running and can hear the sound just as well down there, but the sound is hard to isolate. It's definitely at the rear of the engine but hard to say if it's inside the motor or in Bellhousing

Disassembly and inspection is the only way to know for sure, but keep in mind that each cylinder only fires once every two revolutions, and a rod knock will be loudest, or perhaps only audible, when the cylinder fires.

 

[redfishsc]

Yeah either way I need another vehicle to get around so I'll be parking this old girl soon.

Dashboard readouts all work as does the 4wd and other goodies so I may part her out.

 

[mariodave]

My engine doesn't have a rear lifting eye, is that normal or did someone leave it off?

 

[Schurkey]

Someone "forgot" to put it back on. Lazy ********.

 

[deadbeat]

When I changed the motor on my 97 vortec 5.7, neither the motor in it or the replacement had one on the rear. I have 1970's 350 on a stand that had one on it, wonder if some of the vortecs just didn't have it?

 

[Schurkey]

In the end, I don't see that it makes any difference. I bolt a chain to the front of one head, and the rear of another. Get the engine so it balances properly on the engine hoist hook, then bolt the chain around the hook so the chain can't slide on the hook.

Lift away.

Be sure to mark the links as needed, so the chain can be bolted through the same links when it's time to put the engine back in. You'll want the same front-to-back tilt as when it came out.

You couldn't pay me to use one of those Communist Chinese "engine levelers". Too much wasted height above the engine. The "dirty secret" of most engine hoists is that they won't lift very high. The leverage has been compromised in order to artificially boost the weight ratings. In other words, they may be rated at "two tons" but they did it by shortening the lifting arm; which reduces stress on the too-small hydraulic cylinder, which makes the rest of the small and flimsy structure "acceptable". It's hateful cost-cutting and the consumer loses utility.

 

[mariodave]

Agreed on the leveling bar is useless, I will chain it up as low as possible as this truck is lifted and height will be an issue , thanks.

 

[Erik the Awful]

I use and love my leveler. I bolt the front and back of both heads and everything sits safe and square. I wouldn't lift my Cadillac engine on full length, but it handles a SBC just fine. I was able to pull my Stepside's engine as it sat. For the Suburban I had to remove the front wheels and lower it onto jackstands to clear the core support. If I hadn't lowered the hoist's wheels to fit under an RX-7 I could probably get away without removing the Suburban's wheels.

None of my SBCs have had lifting eyes.