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

[4Cruisers]

When I was back at my place in Nevada in mid-December, I started up my stock '84 FJ60 (~182,000 miles) to let it run for a while, as I usually do while I'm out there. It's been sitting (off and on) for almost nine years. Just before I parked it nine years ago I installed new plugs and wires (plugs still looked good in December). In the last nine months I've replaced the fuel pump, drained and refilled the tank with fresh gasoline, and replaced the original carburetor (which I had rebuilt once in the past) with a freshly rebuilt carburetor. The oil level is good, but I know I need to change the oil (the oil's old, and it's probably been "watered down" with gasoline as a result of the fuel pump failure). It's been starting up fine and, with the freshly rebuilt carburetor, it now idles OK. However, when I started it up in December again it developed a loud knock right away. Mine sounds just like this (video in Post #4):

1985 fj60 engine hard knocking - help

I'll be going back out there in the next month or two so I've been doing some more research into the knock and am just now putting together a plan to diagnose/repair exactly what's wrong. Here's a prioritized list of what I think I need to do, thanks to the advice given others here on MUD:

1. Install mechanical oil pressure gauge:
- I have an old Sunpro gauge, but sitting on the shelf it reads a little shy of 15 psi @ 7,240 feet.
- Is the gauge bad?
- Any recommendations on a new/better gauge?
2. Change oil and filter:
- Probably Castrol conventional 10W-30 oil and a Wix filter (NAPA Gold).
3. Start engine and try to isolate source of knock:
- I was thinking of buying an automotive stethoscope - I found one by Lisle that got decent reviews.
- Where on the engine should I focus?
- How should I document what I find so I can get the best help on diagnosing the problem?
- 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?
4. Remove valve cover:
- Check to see if there's anything visually obvious - should I do this first?
- Maybe if I'm lucky it's "just" a push rod issue like in the linked thread.
5. Anything else I can do while I'm out there?

Thanks in advance for any help. I'd really like to get the vehicle running well again.

 

[roscoFJ73]

Did the new fuel pump need a spacer?

 

[4Cruisers]

Did the new fuel pump need spacer?

Yes, and installed correctly. The fuel pump was installed earlier and the knock just developed in December.

 

[txnight]

Answers/advice to your questions above.

1. 15 psi is fine. Should have no influence on the knock.

2.That's fine. Has no influence on the knocking.

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.

4.yes, I would do this first. If it is a broken connecting rod or stuck valve you should be able to tell.

5. I would also perform a compression test.

This sucks, hope you get it sorted.

 

[4Cruisers]

Answers/advice to your questions above.

1. 15 psi is fine. Should have no influence on the knock.

2.That's fine. Has no influence on the knocking.

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.

4.yes, I would do this first. If it is a broken connecting rod or stuck valve you should be able to tell.

5. I would also perform a compression test.

This sucks, hope you get it sorted.

Thanks for the reply!

1. I'll plan on using the Sunpro I have, just need to get some new/better tubing to plumb it up.

2. I've got new oil in the garage with the vehicle, will get a new filter.

3. Thanks, got it.

4. I'll do a visual with the valve cover off, at least it's easier to remove than on my FJ62's 3FE. I'll plan on buying a new valve cover gasket.

5. I've got a compression tester in the garage with the vehicle, and have done this on the 2F in my '76 FJ40, so it should be easy.

 

[cruisermatt]

I would pull the valve cover first, and if you don't see the problem there then pull the oil pan. Wouldn't even bother with anything else.

 

[4Cruisers]

I would pull the valve cover first, and if you don't see the problem there then pull the oil pan. Wouldn't even bother with anything else.

I'll plan on taking my spare unused oil pan gasket when I go back to check it out.

 

[cruisermatt]

The fact that's it runs and hasn't seized yet means you might have a chance to replace the rod or main bearings and be OK, hopefully it's the pushrod like that other guy's post though.

 

[POTATO LAUNCHER]

Man, thats a tough call to make. I would check for fuel in the oil before turning it over. Might get lucky with a stuck lifter. Next step would be pulling the valve and side cover to verify / pinpoint noise before going into the rods and main caps. Hopefully its an easy remedy since it developed with the engine not running. Worse case would be a siezed rod bearing has spun. Maybe you cought it early enough for an inframe overhaul.

 

[TRAIL TAILOR]

J,

More than likely the upper end is completely dry and cold from sitting. The gas will thin out the oil and it will not coat things as well. The gas will basically strip a majority of the oil off the components.

Did you run it for very long or kill the motor once you heard the noise?

Are you saying the oil pressure is 15psi when running or the gauge you want to use is showing 15psi not installed on the truck? If 15 psi and running at start up and cold that is low...

J

 

[4Cruisers]

I replaced the fuel pump in early April 2016, with a new pump from NAPA, using the appropriate spacer and gaskets. The engine wasn't knocking after the fuel pump replacement. In late October I replaced the carburetor with the rebuilt carburetor. The engine wasn't knocking after the carburetor replacement - it was idling better and not running as roughly as it had been, just as I expected. The next time I was out there, in mid-December, it started knocking soon after I fired it up for the first time. I shut down the engine after 10-15 seconds because of the knocking. I believe I started it again briefly for a few seconds to try and get a better idea of the source of the knocking, but decided it was best to shut it down and leave it that way until my next trip out.

I'm pretty sure nothing accidently fell into the intake manifold during the carburetor replacement, and I'm pretty sure nothing was accidently left in the carburetor that may have fallen through into the intake manifold. However, I did remove and clean the carburetor insulator during the job, so maybe something did fall in and work its way into the head. A visual inspection under the valve cover and behind the side cover should tell me a lot. I'll plan on taking my spare side cover gasket out there as well, along with a new valve cover gasket. I also have some spare push rods from the '86 FJ60's 2F.

I'd tow the FJ60 back here to New Mexico if I had the room to park it - my garage is filled with spare parts (engine, transmission/transfer case, etc.), tools, and a lot of parts awaiting installation into my '86 FJ60 project vehicle (3FE on engine stand, H55f, split transfer case, radiator, winch, OME suspension, dash, seats, etc.). The '86 and the '89 FJ62 donor vehicle are parked side-by-side in the driveway, along with my '76 FJ40. And I need room to park our Malibu and two Silverados. There's more in the basement, but at least (so far) I haven't filled the living room .

I appreciate all of the input, and will document what I do and what I find out. It may be another month and a half or two before I can get out there again.

Anything else I can do?

 

[4Cruisers]

J,

More than likely the upper end is completely dry and cold from sitting. The gas will thin out the oil and it will not coat things as well. The gas will basically strip a majority of the oil off the components.

Did you run it for very long or kill the motor once you heard the noise?

Are you saying the oil pressure is 15psi when running or the gauge you want to use is showing 15psi not installed on the truck? If 15 psi and running at start up and cold that is low...

J

Could the loud knock be coming from the rocker assembly/valves/push rods? I thought a loud knock would have to be from the rod bearings or main bearings.

The 15 psi I mentioned is what my old Sunpro gauge reads just sitting on the end table next to where I'm sitting. I removed it from my '76 FJ40 several years ago because the plastic tubing was brittle and leaking oil. The '84 FJ60 just has the stock gauge in the dash. I didn't look at the gauge while the engine was running, I was focused on the knocking.

 

[TRAIL TAILOR]

J,

Yes, while a knock is often bearing related... it can be as simple as a dry upper end, stuck valve, lifter, especially if it has sat for a long period of time. A dry upper end will cause things to be loud until they get re-lubricated (more than just a ticking sound). One of my old piggies caused a panic more times than I can count. I've started several barn find cruisers that sound like the clip you posted and not a one has been bearing related.

How long did you run the engine? If you turned the motor off shortly after you heard the knock you may have not given it time to lube up, especially if it was cold out.

A sprung gauge is trash and you should buy a new one. Just my .02

Start with an oil and filter change when you go back. Get that gassy oil out of there. Then pull the valve cover and see if all the arms are moving. You can run through all the valves and check without running the engine, just keep bumping the starter until you've seen all the arms move.

J

 

[4Cruisers]

J,

Yes, while a knock is often bearing related... it can be as simple as a dry upper end, stuck valve, lifter, especially if it has sat for a long period of time. A dry upper end will cause things to be loud until they get re-lubricated (more than just a ticking sound). One of my old piggies caused a panic more times than I can count. I've started several barn find cruisers that sound like the clip you posted and not a one has been bearing related.

How long did you run the engine? If you turned the motor off shortly after you heard the knock you may have not given it time to lube up, especially if it was cold out.

A sprung gauge is trash and you should buy a new one. Just my .02

Start with an oil and filter change when you go back. Get that gassy oil out of there. Then pull the valve cover and see if all the arms are moving. You can run through all the valves and check without running the engine, just keep bumping the starter until you've seen all the arms move.

J

Thanks! You've given me some more things to go on. I picked up a new mechanical oil pressure gauge this morning and the automotive stethoscope I ordered will be here Tuesday. The oil filter will have to wait until Monday - our local NAPA store isn't open on Saturdays.

I've never run into this problem with any of the five Land Cruisers I've owned. We bought the '84 FJ60 new, and I've done most of the maintenance myself and documented everything, so it shouldn't be anything major. My '71 FJ40 (with a '76 2F) has also been at my place in Nevada for many years, and it sat, unstarted, for seven years. In 2015 I started it up for the first time after sitting that long. I had changed the oil and filter, drained and refilled the fuel tank, replaced the fuel filter and spark plugs, and it fired right up with no issues. It idles and runs well, especially after installing a freshly rebuilt carburetor. I haven't taken it anywhere but around the property, so it hasn't been on the street yet.

 

[TRAIL TAILOR]

Thanks! You've given me some more things to go on. I picked up a new mechanical oil pressure gauge this morning and the automotive stethoscope I ordered will be here Tuesday. The oil filter will have to wait until Monday - our local NAPA store isn't open on Saturdays.

I've never run into this problem with any of the five Land Cruisers I've owned. We bought the '84 FJ60 new, and I've done most of the maintenance myself and documented everything, so it shouldn't be anything major. My '71 FJ40 (with a '76 2F) has also been at my place in Nevada for many years, and it sat, unstarted, for seven years. In 2015 I started it up for the first time after sitting that long. I had changed the oil and filter, drained and refilled the fuel tank, replaced the fuel filter and spark plugs, and it fired right up with no issues. It idles and runs well, especially after installing a freshly rebuilt carburetor. I haven't taken it anywhere but around the property, so it hasn't been on the street yet.

You can run your hand around on the side of the motor as well to find a general locale of the knock as well.

J

 

[Output Shaft]

Something seized. This is lubrication related. Engine ran fine the last time it ran, sat forever, then bangy bangy on next start up.

 

[4Cruisers]

Something seized. This is lubrication related. Engine ran fine the last time it ran, sat forever, then bangy bangy on next start up.

It only sat from October 20, 2016 until December 15, 2016 - eight weeks. I started it up and ran it for a while in early April 2016 also - no knocking in April or October.

 

[Output Shaft]

How long is the engine allowed to run when it's started up after hibernation? How is it run? (Not how does it run).

There are many opinions on this matter, but I think the engine should run (fast idle) at 1200 rpm for 30 minutes straight if it isn't going to be driven.

The first ten minutes are required to get the coolant up to temp. The remaining 20 help get the oil hot. But the oil never really gets hot enough to boil off any water that may be in the pan.

 

[TRAIL TAILOR]

I only drive my 60 about once every 2-3 weeks right now. I start her up and let it idle for 10-15 minutes and then go for a drive. I always say that if the carb fan is on when you kill the engine that you've ran the engine to where things are happy. That is if the fan works.

Otherwise a 20-45 minute run is a minimal duration if not a daily driver.

J

 

[4Cruisers]

I appreciate all of the recommendations. Next time I'm out in Nevada I'll run the '71 FJ40 accordingly, and after I get the issue with the '84 FJ60 resolved (keeping my fingers crossed) I'll do likewise with it. Then I can set up and follow the regimen for both. We're out there about every two months. My plans are to bring the '71 FJ40 back here to New Mexico after I clear some driveway space (the space occupied by the '89 FJ62 donor vehicle for my '86 FJ60 project).