fzj80 rattle

Joined
Mar 27, 2003
Messages
1,857
Visit site
I posted this to 80scool already, so ignore if you're on there.

My '93 fzj80 is rattling from what appears to be the top end, rear of the motor. It started this morning while my wife was driving. The rattle sounds like a pushrod motor with loose rocker arms, and it varies with RPM. Oil pressure and temp are good, and oil level is normal and oil color is good. I pulled the valve cover, and I didn't see any obvious problems with the camshafts nor timing chain. I'm going to check the clearances tomorrow.

I got an oil light twice last week briefly after starting the motor in the morning. No lights or other warnings prior to the rattle today. Wife said in the afternoon while idling, the motor speed oscillated from 800 to ~1000RPM with AC engaged.

Might this be a valve or lifter? I'm sure I'll be pulling the head, but I'd like to get some ideas on what to look for.
 
Joined
Mar 13, 2003
Messages
5,787
Location
North Front Range, CO
Visit site
Check your heat shields infront of the cat on the front exhaust pipes. My clamps that hold the shields were gone. I used a hose clamp on one and exhaust clamp on other. It made a rattle noise on start up and shut down.
kurt
 
Joined
Mar 27, 2003
Messages
1,857
Visit site
[quote author=cruiserdan link=board=2;threadid=3786;start=0#msg27828 date=1058620092]
Which light?

Pressure or level?
[/quote]Level, I believe. It was in the low row of lights. Where is the pressure light?
 

cruiserdan

SupportingVendor Emeritus
Moderator
Joined
Mar 27, 2003
Messages
24,446
Location
Land Cruiser Heritage Museum broom closet
Visit site
C-man

I must correct myself. there is no low oil PRESSURE light, just a low oil level. I was thinking of the low fuel and charge light indicators. ::) . IIRC the low oil level will come on at about 2 quarts low. If the level on the stick is correct there may be something wrong with the float in the pan. Are you certain nobody has added oil since you had the light come on?

I'll take a stab here and suggest you check the torque converter bolts. If one has backed out it may "bang" on something as the crank rotates. The frequency would, of course, change with engine speed. I have seen this before but not with this particular engine. (A very wild guess).

Please keep us posted with your observations.

Dan.
 
Joined
Mar 27, 2003
Messages
1,857
Visit site
Anyone know the crank pulley nut size? I need to turn the motor, and I don't have a socket large enough to fit on there.
 
Joined
Mar 27, 2003
Messages
1,857
Visit site
Thanks, Dan. Back from Sears and checked the clearances, which are well in spec. Amazing a motor can go 10 years and 146K miles without a valve adjustment :).

In the mean time I pulled the plugs, changed the oil, and found 2 stored codes (24 & 41). I'm thinking the codes are pointing to a wiring short in the loom. Oil and plugs looked fine. I'm putting the rig back together and seeing if I can pinpoint the cylinder, and then going to trace the wiring for TPS and AFM circuits.
 
Joined
Mar 27, 2003
Messages
1,857
Visit site
I did a compression check yesterday, and there is a problem in cyl #5. I've decided to tear down the motor and see what it takes to get it back in shape. Hopefully I can just fix #5 and go on my way.
 
Joined
Mar 13, 2003
Messages
5,787
Location
North Front Range, CO
Visit site
Before you tear it... What was your compression in #5? If it was low, it could be stuck rings. Run some Sea Foam in the oil,gas and in the PCV. Then before you change the oil add a qt of ATF for 5min then change oil. In my 2F FJ60 I had low compression in one or two cylinders and after Seafoam and ATF the compression came back. It must of been stuck rings.
kurt
 
Joined
Mar 27, 2003
Messages
1,857
Visit site
[quote author=landtoy80 link=board=2;threadid=3786;start=0#msg28259 date=1058825944]
Before you tear it... What was your compression in #5? If it was low, it could be stuck rings. Run some Sea Foam in the oil,gas and in the PCV. Then before you change the oil add a qt of ATF for 5min then change oil. In my 2F FJ60 I had low compression in one or two cylinders and after Seafoam and ATF the compression came back. It must of been stuck rings.
kurt
[/quote]Compression was 161psi. Added oil and compression went to 195psi. Not low, but lower than the others which ranged from 175 to 190psi. I have no other symptoms but the rattle/knock, but I'm going to check out the problem while I can still repair the motor.
 
Joined
Mar 13, 2003
Messages
5,787
Location
North Front Range, CO
Visit site
I also dumped some Seafoam in the #4 spark plug hole and let it set over night. I I turned the motor over the next day without the spark plugs. Boy did the Seafoam get all over the garage :eek:

I didn't have a rattle though. But I did get rid of the tap tap tap that would come and go :)

If you had broken rings, what compression would you get?
kurt
 
Joined
Mar 13, 2003
Messages
5,787
Location
North Front Range, CO
Visit site
I had a Chevy 350 7 cylinder. The right rear cylinder was full of oil crud. I got one of those spark plug covers that screw into the spark plug hole and the spark plug screws into it. It keeps oil from coating the plug. After a year of Seafoaming (big black cloud) and ATF before the oil change and using Lucas oil additive, I sold the truck to my boss. He put new plugs in and said What was that thing I put in the spark plug hole? I told him. He said that that cylinder was working fine. That motor was very strong. It would lay rubber just touching the gas.
kurt
 

sleeoffroad

Supporting Vendor
Joined
Mar 27, 2003
Messages
6,349
Website
www.sleeoffroad.com
[quote author=semlin link=board=2;threadid=3786;start=0#msg28261 date=1058826620]
Kurt, ATF in the motor! that's an old one. How about some sawdust in the tranny while we're about it?
[/quote]

My motor must be pretty clean the. :D At CM2003 when the seal went ont he powersteering pump, it pumped all the ATF into the motor. Not knowing this, I added another quart to the power steering system, and that ended up in the motor as well. :(

Ended up having to drain a whole bunch of oil/ATF from the motor.
 

Users who are viewing this thread

Top Bottom