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BigRandy · 02-18-2018, 11:57 PM

Okay, I thought the pecking was gone but it's back. I've got maybe 100-150 miles on the Pennzoil 10W40 High Mileage. I put 6-1/2 quarts of oil and half a quart of MMO in it. Maybe I should have used a full quart or more of the MMO since it takes 7 to fill it up. The reason I didn't is because it looks pretty thin. I also don't know if it's good to run it for the full OCI which may be 3000 miles. The bottle says to use it at every oil change but that's likely a marketing thing to sell more. The motor wasn't terribly dirty when I bought the truck but I've been changing it at shorter intervals to clean out any crud that might have been in there.

Oil pressure still looks good even while clacking so I don't think it's a starvation problem. When hot tit's straight up 30 at 700 RPM and 50'ish at 2K and above.

The pecking is weird tho. It can sit for days and start up smooth as glass. The only time it will clack is after it's been warmed up, shut off and restarted again, but only once in a while. The clack will start gradually and then fade away after letting it idle 3-4 minutes. No way to make it do it. It might clack or it might not.

I can try adding more MMO since it holds more than most V8's. Also thought if it was a valve sticking I night try treating it through the fuel.

Anyone know of a good valve cleaning product to add to the fuel or dribble down the intake? I remember when I was a kid some guys swore that ATF would work wonders on cleaning valves but I don't remember how effective it really was.

I don't see what it would hurt to try it other than maybe fouling the plugs, but that Slobberjet card is so rich right now that the plugs are likely gas fouled anyway. They were 2000 miles ago when I kitted the carb. It runs much better but floods easily so I'll be going back in soon with a new float and to check the jets\metering rods. It's just overall running entirely too rich. Although it has 3.73's and a TH400 I can't do better than about 7 MPG on the highway at 2800 RPM. City MPG is 5.

Unless someone says not to do it I'll drain a little oil and add some more MMO. I'm really trying to avoid the TSB fix Boog mentioned if I can help it.

Thanks!

02-18-2018, 11:57 PM	#11
BigRandy Registered User Join Date: Jun 2017 Location: San Antonio, Texas Posts: 156	Re: 454 Occasional Lifter Tick Okay, I thought the pecking was gone but it's back. I've got maybe 100-150 miles on the Pennzoil 10W40 High Mileage. I put 6-1/2 quarts of oil and half a quart of MMO in it. Maybe I should have used a full quart or more of the MMO since it takes 7 to fill it up. The reason I didn't is because it looks pretty thin. I also don't know if it's good to run it for the full OCI which may be 3000 miles. The bottle says to use it at every oil change but that's likely a marketing thing to sell more. The motor wasn't terribly dirty when I bought the truck but I've been changing it at shorter intervals to clean out any crud that might have been in there. Oil pressure still looks good even while clacking so I don't think it's a starvation problem. When hot tit's straight up 30 at 700 RPM and 50'ish at 2K and above. The pecking is weird tho. It can sit for days and start up smooth as glass. The only time it will clack is after it's been warmed up, shut off and restarted again, but only once in a while. The clack will start gradually and then fade away after letting it idle 3-4 minutes. No way to make it do it. It might clack or it might not. I can try adding more MMO since it holds more than most V8's. Also thought if it was a valve sticking I night try treating it through the fuel. Anyone know of a good valve cleaning product to add to the fuel or dribble down the intake? I remember when I was a kid some guys swore that ATF would work wonders on cleaning valves but I don't remember how effective it really was. I don't see what it would hurt to try it other than maybe fouling the plugs, but that Slobberjet card is so rich right now that the plugs are likely gas fouled anyway. They were 2000 miles ago when I kitted the carb. It runs much better but floods easily so I'll be going back in soon with a new float and to check the jets\metering rods. It's just overall running entirely too rich. Although it has 3.73's and a TH400 I can't do better than about 7 MPG on the highway at 2800 RPM. City MPG is 5. Unless someone says not to do it I'll drain a little oil and add some more MMO. I'm really trying to avoid the TSB fix Boog mentioned if I can help it. Thanks!