i'm looking at a 1980 GMC General Tandem Gravel truck to use around the farm, it has a 8v71 detroit, and an 18speed eaton trans. I'm wondering what to watch out for on this engine, what to listen for on a cold start, is there any acceptable amount of blowby for this motor? It doesnt have a pintle hitch or trailer air brake lines, how hard would it be to plumb it in? One more question, they say the clutch is slipping on it around 40mph, they figure it will cost $800-$1200 to repair it, does that sound right?
The price for the clutch sounds about right, if it does not have blowby, check the oil-it will be low , no seriously it will probably have more blowby than you are use to seeing, unless it has been rebuilt recently, and it will probably smoke more, and has the one of the best sounds when it is winding up How much is the truck? The pintle hitch and trailer air brakes can be done, but it is usually better to find one already plumbed. Unless you know the truck, seller, or it is super cheap, shop around, you can probably find something that is already set up the way you want it.
I agree with Redbank. If you really need trailer, I'd take the time to look for one already set up. It can be done, but you have to consider the cost of the components necessary, the labor time involved, and a someone who is capable of installing it. As for the engine, a good Detroit should fire right off, even when it's cold. You shouldn't have to crank and crank the starter. When it starts, it should run smooth, a little white smoke is OK like with any cold diesel. But rough running until warm up can be, at the least, needs injectors; or could be worse, weak compression. Blow-by is like any other aged engine, you can expect some, but puffs of smoke like a steam train from the valve cover vent hoses is not good on these engines, that means the lower rings are bad. Test drive the truck, get it warmed up, then bring it back to look it over while letting the engine idle. Then check oil leakage from the air box drain tubes, thats the small 1/4" tubes coming down at the bottom/rear of the engine block just above oil pan. If they produce a fair size puddle of oil on the ground in 10 - 15 minutes of idleing, I'd be wary. The engines going to be an oil leaker, but excessive just means your going to have to do some gaskets at some point. A guy asked me once "how do you get a Detroit to stop leaking oil?" I replied "I wouldn't worry if it leaked oil, I'd worry if it didn't". As for the clutch, I'd consider hiring a mechanic to check the truck out, maybe even try to adjust the clutch, he should be able to tell what your getting into. That ain't no $100 clutch job. Aside from all this, I'm with Redbank, ain't nothin' like the sound of a Detroit 2 stroke. My favorite was pegging a 6-71 while grading a hill.
Hey Redbank, is that your Mack on your avitar? Small pic, but looks like an R model. Nice looking truck.
The Detroit is a unique sounding engine and fun to drive..........for about the first half hour. You'll get a workout driving it, plan on shifting from point to point. I drove a General once, it was a nice comfortable truck.
Thanks for the reply's, they are asking $7500CDN for the truck.
Its not cheap running plumbing to the rear. I was quoted about 2300 to get air and a pintle hitch on the back of an IH. Its best to find one that already has it. Some of the suspension parts are hard to find for those old Generals even in bone yards.
Yes it is an R model, I got some more pictures posted under "showtime", search for Red Bank Toys, Thanks for the compliment