Help - Loud Engine Knock '84 FJ60

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Other than the 99-degree heat (both inside and outside) when we arrived, I got a bit of good news to start with. I found my double-bagged set of used pushrods, all 12 of them, in the garage. They're from my '86 FJ60's 2F, and they've been sitting in the garage since I bought the vehicle (with a big hole in the oil pan from a wayward piston rod) almost 15 years ago. It turns out 2 are bent, so I still have 10 good ones. That's enough that I can pick and choose the best replacements for the one or two pushrods that have mushroomed. I've alredy cleaned one up and the rest are soaking in the garage overnight. They should work fine in the '84's 2F.

I packed a few extra tools in my carry-on bag, along with a new mechanical oil pressure gauge (in case I can find/fix the cause of the knocking) and a remote starter (or I might just roll the FJ60 back and forth in 4th gear to get to TDC for both sets of valves). I stopped by an AutoZone near the airport and picked up an oil filter and 10W-30, just in case I get it running again.

On another note, I also confirmed that I indeed have 2 spare FJ60 carburetors, I thought I only had one. Time to re-inventory the spare parts tucked away in the garage.
 
OK, halfway through the initial pushrod clearance measurements. With cylinder #1 @ TDC (or very close) on the compression stroke, engine cold:

#1 0.012" vs. 0.014" - will loosen
#5 0.008" vs. 0.014" - will loosen
#9 0.013" vs. 0.014" - will loosen

#2 0.010" vs. 0.008" - will tighten
#3 0.010" vs. 0.008" - will tighten
#7 almost 1/4" - YIKES! Pushrod moves freely, mushroomed at top - glad I have some good spares.

Before rotating the engine 360 degrees, I'll adjust the 5 valves that seem to be OK. I'll check the valves to see if #7 (intake valve on cylinder #4) is where it should be. If I lay a straightedge across the top of valve springs #2 and #3, the top of valve spring #7 should be in contact with the straightedge, right?

Any initial thoughts before I adjust the first set of valves and rotate the engine?
 
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Even if you get all the pushrods under control, without oil to the head, you're on very borrowed time. If you really have stuck lifters, is there any sense in adjusting the valves? If you do it anyway, and start the engine, you should see significant oil flow to the head within 60 seconds of starting.
 
Well, it's now up to 104 degrees outside, it's predicted to top out at 106 this afternoon. Isn't stopping me now :).

Valve #7 was in its proper position relative to #2 and #3. Turns out I had an almost full can on Mrvel Mystery Oil in the garage, so I poured a couple of capfulls down into the pushrod #7 bore. Adjusted 5 valves and rotated the engine 360 degrees, with cylinder #6 @ TDC on the compression stroke. I noticed that pushrod #7 is pushed up, compressing its corresponding valve. It's contacting the lip of the mushroomed top, and the pushrod is slightly off center. I tapped it sideways and it slipped back into place. At a minimum, that pushrod will get replaced with a good one from the '86 2F.

Here is the second set of measurements:

#4 0.020" vs. 0.014" - will tighten
#8 0.012" vs. 0.014" - will loosen
#12 0.013" vs. 0.014" - will loosen

#6 0.015" vs. 0.008" - will tighten
#10 0.011" vs. 0.008" - will tighten
#11 0.011" vs. 0.008" - will tighten

I'll adjust the 6 valves then rotate the engine another 360 degrees and let you know what I find.

I'll probably change the oil and filter this evening after getting back from Las Vegas and install my new mechanical oil pressure gauge.
 
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shoot, I thought AZ was spossed to be hotter than cali...
 
SteveH said:
Even if you get all the pushrods under control, without oil to the head, you're on very borrowed time. If you really have stuck lifters, is there any sense in adjusting the valves? If you do it anyway, and start the engine, you should see significant oil flow to the head within 60 seconds of starting.
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There are small puddles of oil all along the top of the head, and every surface (rockers, valve springs, rocker shaft, etc.) is coated with some oil. Definitely not dry. And that's after sitting another 14 or 15 weeks since I was last out here. There's a decent pool of oil sitting in the rear of the head (low spot due to slope of garage floor) that's drained from the rocker assembly, etc. over that time. Given what I posted just above, it doesn't look like I have any stuck lifters (unless I'm missing something).
 
Seems like you may have had a siezed lifter. Does the lifter in said hole #7 cycle as it should?
 
Shoot, we got 107 all weekend...
 
Well, I adjusted the second set of valves and rotated the engine another 360 degrees. Pushrod #7 had the same gap as the first go-around. Looking at it closer, the top has been mushroomed and the pushrod has been pounded shorter to the tune of about 1/4", the extra gap when cylinder #1 is @ TDC on the compression stroke. It moves freely up and down its bore, and also rotates freely.

Next I'll do the oil and filter change. If I can verify oil's getting to the top end and I have decent oil pressure (after installing the mechanical oil pressure gauge), would it be OK to run the engine with the valve cover removed? I'd be watching pushrod #7 to see what it's doing. I'm thinking I can then remove the rocker arm assembly, assuming nothing looks unusual, replace pushrod #7 with a known good one, adjust that valve, and see what happens.

Does this sound like a good approach to wind this down?
 
POTATO LAUNCHER said:
Seems like you may have had a siezed lifter. Does the lifter in said hole #7 cycle as it should?
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I know lifter #7 pushed the pushrod up in contact with the rocker arm sufficient to compress the valve spring. That's the position it was in at the time I had cylinder #6 @ TDC on the compression stroke.
 
I hope luck was with me. It's got a new fuel pump, plug wires, plugs, and freshly re-built carburetor. With an oil and filter change it should be good to go. I'm keeping my fingers crossed. Will know more later tonight and again early tomorrow before we fly home. It'll be a while before we get back here. Next time we'll drive the '09 Silverado and bring the '71 FJ40 and Lance camper back to New Mexico, but first I'll have to find a new home for the '89 FJ62 frame and body shell. It's taking up valuable driveway space.
 
I got back from town and drained the oil. Sure enough, there was a lot of gasoline in the mix from the past fuel pump failure. That would explain the fairly sudden onset of the engine knock and apparent oil starvation symptoms. Also, over the past 14 or 15 weeks since I've been out here, oil has puddled at the rear of the head, thicker than I recall, probably due to the gasoline evaporating out of the oil sitting in there. Later tonight I'll install the new oil filter, reinstall the drain plug, and top it off with fresh Castrol 10W/30. Tomorrow morning I'll turn it over with the starter (coil wire removed) and watch what happens with the valves/pushrods/rockers. I'll try that with the mushroomed pushrod #7 (cylinder #4 intake valve) still in there - I temporarily adjusted that valve to 0.008" clearance. Seems to me that will be OK for a temporary fix so I can attach the coil wire and run it to check oil pressure and oil delivery to the rocker arm assembly, etc. Or am I missing something?
 
sounds like a plan. GL!
 
Before I turn the engine over, would it help to dribble some Marvel Mystery Oil over the rocker arm shaft, rockers, adjusters, etc. Anywhere else in particular?
 
Just dribble engine oil over them. If the motor makes pressure you'll have oil in the rocket shaft in no time.
 
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