2F Knocking noise at idle? (1 Viewer)

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Mark has been a 40-series mechanic for a living for more than 40 years. If there's anything he doesn't know about F-series motors, it's not worth knowing.
That doesnt answer my question. I've owned a wrecking yard for 23 years and this a real basic techniques to diagnose an engine knock. I just want to know what playing with fire means? Doesn't make sense. I'm open to learn. We use a squeeze bottle for a fuel pump or a windex bottle sprayed directly in the intake for a carb. That may be playing with fire but how is running a 6 cyl on 5 cyl ?
 
…on a Toyota Landcruiser?

Sorry, I just don’t have the patience.

I have personally witnessed a dramatic deterioration of a 2F bottom end in 45 seconds. Nuf said.

Unsubscribed.
 
That doesnt answer my question. I've owned a wrecking yard for 23 years and this a real basic techniques to diagnose an engine knock. I just want to know what playing with fire means? Doesn't make sense. I'm open to learn. We use a squeeze bottle for a fuel pump or a windex bottle sprayed directly in the intake for a carb. That may be playing with fire but how is running a 6 cyl on 5 cyl ?
Continually running it if there is bearing failure will only make things worse. I think earlier in the thread it said the engine was rebuilt recently (miles-wise)? Was machining followed by proper cleaning involved? Bearing tolerances checked properly? Again, worst case by dropping pan is an unneeded oil change and pan gasket. Worst case by continuing to run it to check other things is a junked block because something avoidable let go.
 
“Sorry, I just don’t have the patience” — don’t understand this response.

A question was asked?

If the recently rebuilt engine grenades, there goes $3-4k. Catch it in time it’s some oil and a bearing with a repair in place. There are any number of possibilities in between.

I’d say Mark’s opinion, as a professional, is that the time from point A to B is as little as 45 seconds. He gave his opinion for free, and doesn’t care to give away more time to explain it. He doesn’t mean literally burnt… but is saying don’t screw around with it. Shut it down before it grenades.
 
I don't want to create any animosity on a forum I just joined. In my experience these engines aren't delicate flowers. What happens when he drops the pan and can't find anything wrong with the bottom end? Now he will focus on the top end. Why not eliminate the possibility of problems from the top end first? He has good oil pressure. Idling it for 30 seconds with the #6 spark plug removed for 30 seconds wont hurt anything. To answer your other question. In the 23 years of owning a 4wd specialty wrecking yard I can think of 4 rigs I got into inventory with the 2F. Three were rusted out 60's and there was no demand for the engines because they don't fail. I had one 40 that came in. Unfortunately it was a sheriff seizure with a meth lab in the back and a court order to crush it as is. We weren't even allowed to take lug nut off it before crushing it. Anyway, an engine is an engine and common sense prevails. If it is a wrist pin or piston slap from an oval cylinder it will probably run forever regardless. I'm no expert at anything. I love to learn.
 
I concur a bit with @crawsfire, with the caveat that diagnosing remotely is difficult/limited. The 2F itself isn't particularly unique or special - it's a derivative of the Chevy 235, which is a pretty common inline 6, with pretty basic/simple/robust construction.

If the it was knocking louder than a salesman at the door, I'd be more in the dear-lord-don't-run-it camp - but it sounded pretty subtle/light in that video clip to where a 30 second run at idle to pull a plug wire for a delta-check and some stethescope checks to narrow down wouldn't (personally) give me heartburn - but that's all somewhat subject to hearing it in person, knowing that is has good oil pressure, and it being my block on the line. But I'm comfortable with engines, and comfortable troubleshooting, and comfortable accepting some calculated risk. (I also don't have a lift, so pulling the pan is a less-fun job.)

Based on their notes in past posts, I lean less towards something like imminent bearing failure...but all I have is below and the video clip (and video typically also accentuates those sharp knocking sounds).
It’s not getting louder with revs
the noise gets softer when the engine is warmed up.
This noise has been with this engine ever since it was rebuilt, it just seems a little louder on startup now.
Oil pressure by the dash gauge is great, it fluctuates around the 2/3 mark predictable with RPM.

Your mileage may vary, as may your knowledge, or your risk tolerances. (And possibly engine tolerances. 😆 )
 
I think it is a spun bearing on rod 6. I remember changing the oil from 10-40 to the 20-50, and at the same time used a NAPA Platinum filter. Ever since then, the oil pressure has stayed pegged at 2/3 mark. Downgraded to a NAPA Gold filter, still stayed pegged on the 2/3 mark. Prior to this oil change, the oil pressure would fluctuate with driving. After, it fluctuated only minimally or rarely on the dash gauge. I'm just suspicious that the startup with thicker oil and the restrictive filter caused the engine to run dry for too long before oil got through the system.
 
I think it is a spun bearing on rod 6. I remember changing the oil from 10-40 to the 20-50, and at the same time used a NAPA Platinum filter. Ever since then, the oil pressure has stayed pegged at 2/3 mark. Downgraded to a NAPA Gold filter, still stayed pegged on the 2/3 mark. Prior to this oil change, the oil pressure would fluctuate with driving. After, it fluctuated only minimally or rarely on the dash gauge. I'm just suspicious that the startup with thicker oil and the restrictive filter caused the engine to run dry for too long before oil got through the system.
Was this ever confirmed, oil starvation as the cause of failure? WIX filters have been discussed as the cause of several motor failures in the 80 section. I don’t think the oil is a concern.
 
Just got the FJ back from the shop. It’s just going to have a little tick. Maybe it’s the fuel pump, maybe it’s the Man a fre distributor. Who knows, she runs great.
 
After redoing some of the grounds ( there were none) the ticking noise has subsided a bit. Still goes away when I pull the #6 spark plug wire. Now mostly hear the ticking on startup idle, but quieter on warm up.

Also purchased a stethoscope. Was able to hear the ticking noise the further back I moved on the engine block.
 
You know, I had a noise just like this by Cyl 6. When cold, you could hear the knock at idle. After a few minutes it would go away. I threw caution to the wind and dumped seafoam in my crankcase and ran it for a couple hundred miles before changing the oil. The noise never returned. It’s been like a year.
 
You know, I had a noise just like this by Cyl 6. When cold, you could hear the knock at idle. After a few minutes it would go away. I threw caution to the wind and dumped seafoam in my crankcase and ran it for a couple hundred miles before changing the oil. The noise never returned. It’s been like a year.
I collected a bunch of sea foam to put in the crankcase but it turned back into water by the time I got home.
 
IMG_0419.jpeg

Can’t remember what cylinder but I did crack a push rod a year ago.
 

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