Firerunner's 91 FJ80 build

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Jan 15, 2011
Threads
2
Messages
30
So... My wife decided that she wanted more seatbelts and room than her 96 4runner had.

I found a FJ80 with a whole lot of miles (313k) for not a whole lot of money (1300.00).

The rig is sort of a conflict in maintenance history. On one hand, I think I have every single smog certificate, maintenance record, etc since the vehicle was almost new. I know that it spent 1992-2002 in Southern California, where it was owned by a radio engineer who would use it to go out to remote repeater sites. In an email that he sent the family that sold the rig to me, he claims that he "did air" only a couple of times and only for a few seconds. He then goes on to define "doing air". He also writes about his bug screen, which is a piece of residential screen stapled to a wooden dowel. It sits in front of the radiator to prevent bugs from getting caked in the radiator. It's still there, even though the rig is on its third radiator... Which is leaking.

The body and interior are in great shape. The clear coat is shot. The driver's seat bottom is shot. The window tint (aftermarket, I assume) is purple, faded and torn.

The maintenance list is extensive. Most immediately, it needs the entire front axle redone from hub to hub to pinion flange. The bearings are wailing. The differential backlash is about an inch, by the sound of things. The birfs are clicking like they are completely dry.

The one benefit to living near Fresno is that both Trail Gear and Marlin Crawler are easily accessible. Along with 4.88's from Iron Pig, and Yukon Zip air lockers (best price I found was actually Amazon), I've got rebuild kits and rubber wipers in hand. Next week, I'll try to knock out regearing and rebuilding the knuckles.

The engine had some obvious vacuum leaks. I've been chasing those down as I go. The vacuum hoses were original, by the looks of it. I bought all the vacuum line that my local Napa had... And still didn't have enough to replace everything. It's idling smoother, but still has an intermittent miss.

I likely have an engine oil leak somewhere. It was pretty grimy. I've been cleaning as I go. It's getting better. Running a bottle of seafoam through identified an exhaust leak at the rear exhaust flange coming off the manifold.

I'll keep this going as I work. Initially, here is my catch up list:

Diff breather extensions

Remove running boards

Remove mud flaps

Fix radio antenna

LED interior lights

5% tint rear / 30% front windows

Clean window switches, fix drivers side rear

Dialectic grease and clean contacts on all plugs and connectors

LED marker, brake, tail, signals

Back row seat retainer straps

Tailgate carpet fix

Gear shifter window

Transfer case lever boot

Hood struts

Spark plugs

Wires

Cap

rotor

Waterproof ignition

Fuel filter

Transmission flush, filter, adjustment

Seafoam treatment

Control arm bushings

Hitch pin sway bar disconnects

Parking brake handle replacement

Left rear door panel

Drivers seat bottom replacement

EBC FJ 100 brake pads

Adjust rear drums

Adjust parking brake

Adjust throttle cable

Check timing

EGR system cleaning

Steering column screws

Radiator

Rear hatch child lock

Door window and lock switches and relays





Factory Parts to Acquire

Top of steering column cover, black

Transfer case shifter boot

Gear selector indicator strip

Parking brake handle, brown

Sun roof trim, rear, brown

Drivers seat bottom for sure, back maybe.

96E63EF2-9F09-4C26-9528-CBD210842DDD.jpeg


DE59DEA7-BE43-4286-8D21-773B6FCFE7F5.jpeg
 
 

That's great info. Thanks!
 
Good luck. I've been going through a similar process of fixing up an FJ80, check out my thread maybe there will be ideas that can help WRT the 3F-E.

I found it and read it last night! I'll be following. Cool build.
 
I spent the last couple of weeks trying to get the big things out of the way.

I installed a 2" Tough Dog lift kit, Sierra Gear 4.88s from Iron Pig Off Road, and Yukon Zip lockers, and rebuilt the knuckles with Trail Gear rubber wipers and Marlin Crawler Eco seals. Yukon left a part out of one of the locker kits, so I had to drive to Fresno to get it, but their customer service was excellent and they had the part waiting at the door for me.

Installing the suspension war painless... Almost. The driver's side lower shock bolt was not willing to come out. It appears that when the original owner had the stock length KYB gas-a-just shocks and rear air bags installed, the installer didn't use anti-seize and put plenty of torque to the bolts. The head of the bolt twisted off with very little effort. The rest of the bolt didn't want to move at all.

That issue took me and a friend about 4 hours to resolve. Heat, RB blaster, chisel, drilling the bolt and adding more RB blaster.... No use. After breaking off an easy out in it, I finally cut the mount just in front of the end of the bolt and rethreaded it 1/2-13. I can add back tubing later. The shock is still riding on the mount.... And the new shock bushings are sleeved, so I'm not worried abbot tearing them up.

Today, my pit crew helped me put 36x13.50-15 Iroks from my 4runner rock crawler on it, since the PO's 235/75R15 street tires looked ridiculous with the lift. They made the speedometer look pretty cool though. Driving with them was probably the only time the speedo ever went to 90. My cell phone GPS was reading a more realistic 62mph.
 
I adjusted the throttle cable and kick down cable today. It created an entirely different vehicle. A steep grade in my street went from a 20mph venture on 235/75-15s to a 35mph one on 36x13.50-15s.

The steering has been a little unsettling since the lift. I might play with a panhard lift bracket in the future, but for now, I've slightly tightened the steering box adjuster. That took about 50% of the play out of it.

When I did the rear axle, I found that the LSPV bracket wasnt bolted to the axle housing. I reattached it, but I never addressed the angle of the rod.

Most of the steering "funkyness" is occurring during downhill breaking. I think my rear brakes aren't contributing much.

That might be an issue to address tomorrow. Brakes are important.
 
Old wheels and tires... From my old 86 4runner rock crawler. I hate chrome rims. Looking for a set of black steelies to mount 35" KM3s on.
 
Well, I got a set of 4 35x12.50R15 BFG KM3s on a set of black steelies, for 1300.00 from 4WP.

Then, I got a used Trail Gear tube bumper for 400.00 used.

The last tank of fuel, driven mostly on 235s with stock gears, and poorly adjusted throttle and transmission cables resulted in 108.6 miles driven on 14.86 gallons of gas, or 7.5 mpg. The second tank, driven mostly on 4.88s and 36" iroks, resulted in 112.6 miles driven on 15.06 gallons of gas, or 7.47 mpg. This was prior to the BFGs and bumper swap. This was also all short trips around town as I broke in gears.

I fueled up again at the start of the trip to get the bumper. Unfortunately, I forgot to reset the trip odometer for about 17 miles, but as of right now, it looks like I've burned 3/4 of a tank and have traveled about 130 miles, all of that being on the BFGs and mixed highway and mountain driving.

I pulled the plugs and found this that the old plugs were NGK BPR5EGPs, all of which should have been replaced sometime during the GW Bush administration.

They were replaced with BPR5ES-11s.

In doing so, I found that the number 6 spark plug wire was from a different set than the front five, and that the connector inside was mangled and crushed. I doubt it has been getting good contact for some time. I massaged it back as best I could until new wires, cap and rotor get here. The rig already idles and starts smoother. I'm hoping the refreshing of the ignition components will result in at least a slight fuel economy increase.

It's amazing to me that this thing passed smog this way. The cats are a decade old, as are the 02 sensors. The EGR and modulator are fairly new.

DFAE91F2-3582-453F-B59F-45D698261BC6.jpeg


986F3D32-A02D-4894-9799-A01AB7D677F4.jpeg


FFA53A5D-A03A-4E8E-9BE4-72B9370F23B2.jpeg


069438E2-B175-4758-9881-086A4BAAE3B7.jpeg
 
I've continued to fight the mpg battle. Still haven't adjusted the valves, and I think I still have a small vacuum leak. Still an occasional miss at idle, but I'm up to a fairly consistent 10mpg.

I've had a phantom door unlocking issue for a while. It will go days without acting up, then seemingly out of nowhere, the electric door locks unlock while driving.... And continue to do so every few seconds.

In addition, one of the rear windows kept falling off the track. I think I've got that figured out. The rail under the window that the window rides on had slipped forward about an inch, which allowed the wheel on the lift arm to slip out of the track.

That send to be resolved now, simply by sliding the track back in place.

I disconnected the hokey aftermarket remote door lock / alarm system. Perhaps that will fix the phantom. Only time will tell.

I still haven't hooked the lockers up, as I haven't fully figured out where I'm going to mount the air compressor, and haven't had time to build the rear crossmember / air tank yet. I do have a nice piece of 4"x6" 1/4" wall tubing for that purpose.

Still, the kids requested a mother's day trip, so off we went.

The stability that the KM3s and the tough dog lift give make this like cheating.

0704E12B-9408-4A66-8BEA-41407A0B3861.jpeg


1F10E590-6B96-4723-A455-52C45A2ACE17.jpeg


7609150C-6447-4419-9625-1A2B8575FE2E.jpeg


E9982704-E258-4394-B033-FAFC9C7D121C.jpeg


C877D5E2-F6E1-4983-BA3D-BC350B81B19A.jpeg
 
Bumper and window track

D1989E7F-6A9A-419E-B30C-8D1B799E2254.jpeg


9D76136F-A5CC-4255-AE5E-19CD758CBCB4.jpeg


D82DD769-7E3D-4578-9D75-288FA0C1EE98.jpeg
 
That window track will continue to cause issues. I glued mine with flowable silicone, and haven't had issues since. You might as well do both rear windows.
 
You should be able to get at least 11 around town and 12+ highway, that's what my 91 gets with 4:88's, a winch, front and rear bumpers and 315/75/16 tires.
 
You should be able to get at least 11 around town and 12+ highway, that's what my 91 gets with 4:88's, a winch, front and rear bumpers and 315/75/16 tires.

That's what I'm shooting for, at this point. The wife is daily driving it now. That should be worth a couple mpgs by itself!
 
I've continued to fight the mpg battle. Still haven't adjusted the valves,
Valves should be adjusted/checked every 15K miles according to the FSM. If yours haven't been done in 28 years, you may want to look into that.
 
Valves should be adjusted/checked every 15K miles according to the FSM. If yours haven't been done in 28 years, you may want to look into that.

Yeah...I've been thinking the same thing!
 
I do mine every 2 years; right before smog... last months numbers made me wonder if the machine was reading anything let alone my 3fe; but I watched the whole time and it just burns that clean. At a whopping 12 mpg!!!
 

Users who are viewing this thread

Back
Top Bottom