Long Term Follow Up & Trail Photos
<Click on any image to enlarge>
1000 Miles Later........
Engine
The engine really tended to run rich, and would ping moderately under highway
loads. Retarding the timing to 8 degrees BTDC helped the ping, but probably I'll
have to bite the bullet and start experimenting with changing the carb's jets
and metering rods. I didn't find the air/fuel mixture gauge to be overly useful
because of its wide fluctuations. Apparently these gauges are a little
misleading: the oxygen sensor sends either a 0.5 or 1.0 volt signal if the
exhaust is too rich or lean, and cannot relay any additional information
about the degree of richness or leanness. Modern EFI engines with a closed loop
system and oxygen sensor can maintain the ideal 14.7:1 air/fuel ratio because
the computer is instantly changing the fuel mixture with every engine revolution
depending on input from the oxygen sensor. Apparently one can purchase a gauge
that is more representative and accurate, but these cost thousands of dollars! A
friend recommended using a "Colortune" transparent quartz sparkplug
insert that is more accurate in relaying information about the air/fuel mixture.
That'll come later, because there's more serious problems....
There's also a strange slow oil leak from around the oil pump and bottom of the timing chain cover. I'll see if it's just a matter of tightening down the bolts. Otherwise I'll probably just feed the engine oil....it's a royal PITA to change the cover and gasket! Hey, it wouldn't be a true Jeep motor if it didn't leak somewhere!
The engine has developed a heat soak problem, and coolant would boil out of the recovery tank upon shutting down after a hard drive. It boiled over again on a trail ride where the Jeep was idling for long periods with the AC cranked in 90+ degree weather. I don't know why this should happen with a mildly built engine that has the original thermostat, fan, recored radiator, and shroud. The radiator cap is new and the system is appropriately pressurized, and I don't think that it's because the coolant is circulating too rapidly - otherwise it should be overheating at high RPM or on the highway. The tranny cooler was spaced 1" away from the AC condenser, and isn't overly large. And I don't think that the engine is running too lean or too advanced, or the plugs are too hot. Plans are to go over the hoses to be sure that none are kinked, and to add an auxiliary pusher fan.
I don't know how cold the original AC units were when they were filled with freon, but the R134a-filled unit doesn't exactly frost my feet. After removing the original rotting carpeting and subfloors, and relining with Herculiner, I discovered that there is a tremendous amount of engine and exhaust heat that is now radiating through the floor into the cab. (That probably explains the thick subfloor and wool carpet!). Plans are to reinstall the subfloor using the originals as templates for new plywood units, backing the floors with aluminum-backed DynoMat, and reinstalling carpeting from a kit that ACC sells.
The rebuilt alternator (tweaked from it's original 60 amps to 95) burnt out it's main bearing. It was replaced with a new unit from a later model Wagoneer (those came with 90 amp alternators to power all the electrical accessories that those beasts had in their final years). Also, the cheesy OEM battery clamp wasn't enough to hold down the battery on trail rides, so it was replaced with a more standard crossbar and J-rod assembly.
Exhaust
The Flowmasters sound great! At cruise the interior resonance is minimally
objectionable, and at idle there's a deep rumble that crescendos to a snapping
roar when the stupid pedal is pressed hard. Unfortunately the headers weren't so
impressive. The header flanges evidently weren't precisely machined flat enough
for the copper gaskets to seal. In addition, when they were replaced with more
forgiving fiber gaskets, there wasn't enough flange area to sufficiently support
the gasket around the exhaust ports. As a result, I have a persistent header
leak from the number 1 and 2 cylinders, and have already burnt through two sets
of fiber gaskets.
I called Heddman to see about getting another pair under their lifetime warranty, and was dismayed when they demanded that I first send them back the headers for inspection before they would possibly authorize another replacement pair! This would effectively ground the Chief...perhaps for as long as 6 weeks if I had to wait for another ceramic coated set!
So far, I'm living with the header leak until I can't stand it anymore. Then I'll have to bite the bullet......!
Drivetrain
The tranny temp gauge consistently says that the oil temp is 288-300
degrees! However, a check with an infrared thermometer shows that the oil is
actually 160-180 degrees, and I've never smelled hot tranny. Despite this, the
tranny quit at 1000 miles. This turned out to be due to the clutch seizing in
the remanufactured torque converter, sending showers of metal shavings into the
tranny, radiator, and auxiliary cooler. Jeff replaced the converter, rebuilt the
tranny, and flushed the system at no charge. Now the gauge still reads hot, so
it may be due to a bad gauge or sender unit. Time will tell....
The front axle grenaded one night while trying to muscle up a small ledge. Evidently I gave it a little too much gas and launched the nose over the top. When the front end landed the passenger side upper balljoint broke, binding the axle u-joint and subsequently snapping the axleshaft. As the balljoint broke it also split the knuckle in half. Sadly, the entire axle housing assembly needs to be replaced. The good part is that this is a good reason to get rid of the funky vacuum-disconnect Narrow Track Dana 44 Wagoneer axle that came with the Chief, and it was replaced with a true Wide Track axle from a J10 truck. Also, I can now install that ARB locker that previously didn't fit into the old axle due to its unusual axle spline setup. Now all I need is a wide Dana 60 rear axle - until then I will have to be content with looking at the Chief with a Wide Track front axle and a Narrow Track rear axle!
Body
Boy does that SJ frame ever flex! It must be the C-channel design. Whatever
the reason, it's impossible to open or close the tailgate when the Jeep is
twisted, and flexing maneuvers provoke a lot of creaks and groans from the
tailgate area. This is probably why the Bondo on the tailgate is starting to
crack....!
Heat control is a major issue, even with the AC and dual rear passenger fans. Problem is that there is a *tremendous* amount of heat that radiates from the tranny, engine, and exhaust through the Herculined floor into the cab. This probably explains why the original interior had such a thick subfloor, padding, and carpet. Much as I wanted a true wash-out interior, I will probably have to reinstall a new subfloor using the original cardboard pieces as templates for new plywood ones, and lay aluminized Dynamat on the floor.
June 5-9, 2000 Tellico Upper ORV, Murphy NC
Here's some pictures from the Chief'is maiden voyage Tellico. It took a little adjustment to forget about the ride characteristics of my TJ and to get accustomed to the enormous width and length of the Chief. Even with the relatively tall-ish 3.73 gears, the combination of a healthy built-for-torque V8, automatic tranny, and long wheelbase made crawling over most obstacles easy - especially the ones that tended to hang up the short-wheelbase Jeeps with stock engines. I even managed to make it up SlickRock (with a little help, because I had no winch).
The NarrowTrack Wagoneer axles enabled the tires to tuck nicely inside the fenderwells. However, this also meant that the fenderflares were the first thing damaged when the Chief took a bad side-slide into a rock.
Oh well, it needed some "character marks"!
