1984 Chevy M008 Diesel Revival - Project RejectPosted in Project Vehicles on October 1, 2007 Comment (0)
This '84 M008 had us worried for a while, its 35,443-mile motor refusing to start for the longest time. This wasn't entirely surprising, considering that it'd been sitting for a long time and with several orifices on the 6.2L diesel open to the unforgiving outside world. Also, the liquid in the fuel tank was highly suspect, plus the electrical connections used in the revival attempts were a questionable collection of jumper cables; bad vehicle wiring; and even worse, temporary wires strung wherever needed.
Then, with most of the air bled out of the injector system and with perfected jerry-building of the wiring, one day the clouds parted, the beast shuddered and woke up. It remained running, though shaking and coughing a bit, but to us it was a sweet sound-and smell and smoke. We'd swear we heard the starter motor make a sigh of relief.
While a monumental step in the right direction, the fact that the motor indeed ran did instantly necessitate a flurry of other tasks. Now it suddenly mattered that there was no radiator, that a lone gallon of oil resided in the crankcase, and that the temporary electric fuel pump's hose was resting against the exhaust pipe-among other things. Plus the stuff we hadn't even thought about yet.
Putting the tranny in Reverse and Drive was rewarded with movement in the respective directions, a definite plus. A quick check of the dipstick revealed a severely overfilled transmission. No biggie, as a TH400 always spits out what it doesn't want. More importantly, this pickup was practically a driver now, except for those aforementioned details.
A collection of household and plumbing items were used to connect a garden hose to the severed lower radiator hose to provide cooling, and to some extent, flush the system.A vacuum-cleaner attachment secured to the remains of the upper hose was intended to spew the dirty water outside the engine compartment, but although the motor did its best to shudder along, nothing came out.
Part of the reason, it turned out, was that the thermostat was plugged with debris, and after removing it, all kinds of goo came spraying out. A borrowed radiator from JET Sales-the same friendly surplus/junkyard establishment that the pickup originated from-was "installed," and an upper hose of sorts was created. We had a used lower radiator hose off of an '86, so it was very much an upgrade over the cut '84 vintage hose.
For some obscure reason, the solenoid for the glow plugs began to work, so the engine end of things was pretty much a done deal for now.
But a 4x4 consists of several more parts, some of which are downright important. More prodding and poking was needed before driving off on the inaugural journey. Consistent dripping from the Dana 60 meant it still had oil in it, but the transfer case and rear axle looked suspiciously dry, so we pulled the level plugs on them. Good thing, as the NP208 was a few quarts low.
Thankfully, the auxiliary fuel pump used in the starting attempts was not needed to run the engine. It had been powered by a separate battery with jumper cables, which isn't the most practical setup for a vehicle that actually moves. A bungee cord was used to keep the electric pump and its hose away from the exhaust, because that was quicker than removing them.
Although the victory tour wasn't planned to be more than a mile or so, the cracked tires on split rims in the rear bothered us, as did the mere three lug nuts per wheel. We'd been on Interco's waiting list for blems for a while, but had only three of the 34x10.50/16 LTB Swampers mounted up on the freebie rims at this point. Needless to say, two went in the rear. Since there wasn't much tread on the front tires, the size discrepancy didn't much matter. Besides, with fresh TSLs and a Detroit in the rear, four-wheel drive really shouldn't be necessary on this trip anyway.
After having traded 10 chromed 1/2-inch lug nuts for 24 regular 9/16-inchers (all used, of course) there was enough to put a full set of eight on each wheel with a couple to spare. Not that we had a spare, but still.
A final, hurried check of all the essentials and we were merrily on our way ... heading straight for a steep slope.
It can be a bit busy when driving an unfamiliar vehicle for the first time, especially when you don't know what works and what doesn't-or even how the things that do function will react. There are lots of new sounds, smells, and responses from the vehicle, some of which may take some getting used to.
For example, it sure felt as if the HydroBoost-assisted steering was a bit too light to the touch. Sure enough, there was no steering. We'd forgotten that the drag link had been disconnected to facilitate flat towing with the steering column locked. After a quick fix, we were sputtering up the driveway for the premiere cruise. We even made a mental note to remember to tighten the tie-rod end with a wrench, and put a cotter pin in the castle nut at some point.
Another steering woe surfaced during the victory run, and the angry noises from the power-assist system, once warmed up, were traced to a very loose belt. The power-steering pump is supposed to be driven by two belts, but we'd removed the one that also runs the primary alternator since all the charging wiring was boogered. Apparently, whoever took the radiator and the other alternator had also planned on removing the pump, but only got part way. Tightening the two remaining bolts and replacing a missing third one allowed the tight, if only single, belt to provide near flawless steering. Good thing, since the horn didn't work and the brakes were iffy.
It was not an uneventful drive, but as you can easily deduct from the fact that you're reading this, we lived through the shakedown run. Among the flaws that surfaced, the most obvious was that the tranny didn't want to shift up, had no compression braking except in First gear, and made terrible noises on deceleration. Except for the military blackout lighting, most of the lights didn't work, which was just as well without a charging system.
Making the TH400 shift correctly was as simple as replacing the vacuum hose between the pump and the throttle valve (since diesels have no vacuum, there's a pump for the sole purpose of feeding the vacuum modulator on the tranny). Plus, with toasted wiper blades, a windshield-washer hose could be put to better use this way. Those miserable sounds on deceleration were still there, unfortunately.
It'll take some additional tinkering to get this junkyard refugee in better condition, even if the goal is only to make it driveable and reasonably dependable in the dirt.A good used radiator has been located through Diesel-Tune, a 12-volt conversion will negate the need for the second alternator (but make the 24-volt starter miserable, again), and we've got a line on window glass for the doors.
This fine tuning will likely take a while as the work on this fine pickup is done on a spare-time basis and we're trying not to spend any money on the needed parts. When PROject reJECT returns to these glossy pages, it'll hopefully be to show how the dump-bed conversion worked out. It'll be Part 2.99 ... or, "How to triple the value of a cheap pickup." By Part 3 it may even run well.