Help - Loud Engine Knock '84 FJ60 (1 Viewer)

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how does the engine start after sitting a while?
right up?
or does it need to be a cranked a while?

mine sits weeks at a time as well. if i don't pump the gas a few times prior to attempting to start it....it will not start. i use that to take advantage of getting it to "prime" the oil. i'll let it turn over for several, several second duration's, before actually trying to get it lit.
 
Same as I do with my '76 FJ40 - I pull out the choke knob, pump the accelerator pedal to the floor twice, then hold the pedal down about halfway while turning the ignition key to start. It usually takes about 10 seconds or so to fire. Sometimes I have to repeat the steps, but not usually. Of course it starts up and idles much better with the freshly rebuilt and tuned carburetor, new fuel filter, and fresh gasoline. I can drive the vehicles around the property (~3/4 acre), but not on the street - neither is currently registered or insured.
 
In reading a thread in the FJ40 section this afternoon I ran across a post from SOAZtim (Post #55, here: Our 1976 FJ40 - "Rockford" and Post #61, here: Our 1976 FJ40 - "Rockford") about the knocking in his '76 FJ40 2F. That got me to thinking more on the issue with the 2F in my '84 FJ60. After replacing the fuel pump in April last year I was able to start it and get it running, but it was running very rough. That's when I decided my next step was to install a freshly rebuilt carburetor, which I did in October (I didn't start it up again between April and October). It improved quite a bit, and would idle without the choke, but was still rough. Then in December, when I next started it, I noticed the loud knock. I'm wondering if it was running ragged because one or more of the cylinders was not firing, and there was some cylinder washdown, leading to the knock. One more thing to check when I'm back out in Nevada next month.

Any thoughts?
 
I have had an exhaust leak around the manifolds cause me a good scare based on knock. Go away though as engine warms.
 
Thanks, Jim. My current Land Cruisers have either a '76 2F (two of these), an '84 2F, or an '89 3FE. I'll be pulling the valve cover on my '84 FJ60 next time I'm out in Nevada to try and find the source of the newly-developed loud knock at idle. I'm expecting the locknuts to have 12mm heads. In response to an earlier post I received a lot of good suggestions on how to approach diagnosing the knock.

Well, I'm back in Nevada and had a few minutes just before lunch to pull the valve cover. The top end has been getting oil, and generally things look good/clean. However, when I took a look at the pushrods I found some issues. I have three stuck pushrods, cylinder #1 exhaust, cylinder #2 intake, and cylinder #4 exhaust. I can't spin/rotate them, and there's absolutely no vertical play. Even worse, the head of the pushrod for the cylinder #4 intake valve is mushroomed. Next time out here, when I'll have more time, I'll pull the side cover and check things out further.

Any thoughts on what the cause might be given the above? I'll post some photos tomorrow morning after I download them to my other computer.
 
1985 fj60 engine hard knocking - help
- On the thread linked above someone posted that you should remove the plug wires one at a time.
- If the knock goes away or gets quieter with a plug wire removed, what does that tell you? Why?

3.The idea is to simply disconnect each cylinder for a moment to see if it makes any difference in the way the engine runs. The one that makes no difference is the problem cylinder.

Not as pertainant to you now that you've Narrowed this down to your push rods, but I'll put it up for future readers. I read What TXnight posted two different ways, so I'll clarify in my words. for an engine knock you pull each plug individually and whichever plug makes the knock go away is problem cylinder. the idea is that with the play in the bearing, when the combustion occurs it throws the connecting rod against the crank with more Force, but when it's just getting dragged Along by the rest of the cylinders the knock isn't quite as loud.

As for your problem, you might want to search "sticking valves paper trick" on YouTube to see if that's the reason your lifters might not be lifting. Basically you hold a paper to your exhaust tailpipe, and if it's all Flappy that indicates a sticking valve. HTH.
 
Photos:

2F-Pushrods-1.jpg


2F-Pushrods-2.jpg


2F-Pushrods-3.jpg


2F-Pushrods-4.jpg


2F-Pushrods-5.jpg
 
I was expecting to see more oil...
 
@Mace, is TDC where the oil gets to the top? I can't recall but I thought it was off of TDC where the cam lines up with the oil galley. I know that the bottom end and cam are all getting oiled thruout but IIRC the top got squirts only every cam rev, and if you're not lined up just right you won't get rocker oiling while priming.

The oil passage opens right as the #6 intake valve closes. On a 2F anyways.
 
might try to line it up to where you're supposed to get oil up there and pull the diz and prime to see how much flo you have...
 
Maybe it's just the pic but that cup doesn't look right.

View attachment 1428138

That's the pushrod end that mushroomed, on cylinder #4 intake valve.

Seized lifters?
When you remove the side cover, pull each lifter... If you can.

I noticed that the valve springs are compressed for cylinder #1 exhaust, cylinder #2 intake, and cylinder #4 exhaust, and the corresponding pushrods are tight and can't be moved at all - seized lifters on these?

I was expecting to see more oil...

That's kind of what I thought, but wasn't sure. The vehicle had been sitting in a closed garage since mid-December since I last started it and heard the knocking. Would that 13-week period of time allow enough oil to drain from that area to make it look drier than it should?
 
If there's any pressure on the rocker arm the push rods won't be able to be moved.

Maybe align the flywheel at TDC and check the valve lash clearance on the 6 valves, then spin it 180° and check the other ones.
 
If there's any pressure on the rocker arm the push rods won't be able to be moved.

Maybe align the flywheel at TDC and check the valve lash clearance on the 6 valves, then spin it 180° and check the other ones.

Thanks - will do. I've been reading up some more this afternoon and am starting to get a pretty good mental picture of how things are supposed to be. I went out to the garage to take a look at the recently rebuilt 3FE I have on an engine stand in the garage and take some notes. The machine shop set it with cylinder #1 at TDC on the compression stroke, so I verified what I saw with the valve adjustment info I found here on MUD. Now I understand better what to look for (what's normal) when I get back out to Nevada to do some more investigating. I'll also do a valve adjustment on the 2F in my '76 FJ40 before my next trip, that'll help me a lot as well.
 
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I would expect every dish shaped surface would still be holding a pond...
 
I would expect every dish shaped surface would still be holding a pond...
That's true now that you mention it. More to investigate. I'll be taking a mechanical oil pressure gauge out on my next trip along with a bunch of other tools. I can rule out some of the usual suspects, for example rocker support w/oiling provision in wrong location, head gasket installed backwards, etc. seeing as how the engine's never been touched (I bought the FJ60 new).
 
Regarding the rocker assembly oiling:

When the engine is idling, you should see oil dripping from everything up top. Oil dribbling out of the end of the rocker arms, oil dripping from the rocker spacer springs, oil pooled in every recess. The whole thing should be wet with oil & dripping slowly.

Here's a very tightly cropped in video (that's why it's kinda blurry) of my engine slowed down 25% of the rocker assembly running at idle. You can see oil dripping from the end of the rocker support shaft on the right. Nothing has been cleaned ever in this rocker assembly. It's 30 years old with 270,000 miles on it.

The picture you showed of your rocker assembly looks cooked & dry. Too much carbon deposits for a well oiled engine.

 

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