1st Time Diesel Owner - Have some questions -'83 6.2

[Blue66]

Hi all:

I purchased a 1983 GMC C-30 Crew Cab Dump truck last week. It's a High Sierra with the SM-465 tranny. I have never owned a diesel, and am not particuarly fond of them, but the truck is in very nice shape for being in the salt belt (texas truck), and it seems to run and drive nice. It has a 6.2 witch is supposedly a Jasper engine with 30,000 miles on it. I have a couple questions that may seem like common knowledge to you guys:

What oil should I use, how often should it be changed?

How often should I change the fuel filter?

The previous owner has a button on the dash to activate the glow plugs. I'm assuming he did this because the relay or switch went south. I know they should run automatically. Right now, when cold, I push the button for about 5-7 senconds, pump it once, and crank it over - How does this sound? I dont mind hitting the button, as long as I'm not doing something wrong. When cold, it runs rough for about 20-30 seconds then clears up. I'm assuming this is acceptable for a 23 year old diesel truck??

Any other info on how to keep this truck running OK is appreciated. I use it as my second vehicle and to haul stone. I've had many trucks, and have worked on alot of them, but have 0 experience with a diesel. What is the opinion on the 6.2? I've heard they are OK if you take care of them and use them realistically.

Thanks!
-John

[ZZ]

Welcome to the world of Diesels and the Diesel Page. Give it time and a chance and you may be a Diesel Head. The 6.2 is good & reliable engine if you treat it right.

I recommend running Shell Retella Diesel oil. There are other good oils, but just make sure it has the "C" classification. C is for compression fired engines and S is for spark fired engines.

You are doing right on the holding the glow plugs for 5 to 7 seconds on a cold or cool engine. You can also hold them for 3 seconds after it starts every 10 seconds till it smooths out.

I try to change my fuel filter every six months unless I get some bad fuel.

[Bnave95]

Welcome to the world of Diesels and the Diesel Page. Give it time and a chance and you may be a Diesel Head. The 6.2 is good & reliable engine if you treat it right.

I recommend running Shell Retella Diesel oil. There are other good oils, but just make sure it has the "C" classification. C is for compression fired engines and S is for spark fired engines.

You are doing right on the holding the glow plugs for 5 to 7 seconds on a cold or cool engine. You can also hold them for 3 seconds after it starts every 10 seconds till it smooths out.

I try to change my fuel filter every six months unless I get some bad fuel.After much reading here you will learn a LOT! Just about any oil for a diesel will work. What are 6.2 and 6.5 likes is a CH4 ses rating. If you knew what glow plugs were use you could go longer on the button. The last owner should of told you,or go back and ask. Say he installed 60g glow plug,hopefully then if it's really cold you could go as long as 15 sec. ZZ has a good ideal for after it starts. On computer modles this is done. Oil change at 3k. Use a good filter and stay away from Fram filters. Soot control is important, By product of burning diesel.

[Subzilla]

No need to pump the pedal prior to starting. This won't accomplish anything as the injector pump does not move fuel until the engine turns over. Usually in warm weather, just hit the glow plugs and she'll fire up. In colder weather, you may have to depress the pedal half way while cranking. Yes, it will run rough for the first 5 - 10 seconds or so but this is quite normal.

The 6.2 is a simple engine to work on and can be very reliable. You have to be patient with the acceleration of the non-turbo version but it will get you there. I've got 253k miles on the Sub and there are many members here that have many more miles on their 6.2/6.5's. You've come to the right place to get your questions answered. In short time, you'll find that your membership fee was money well spent.

[trbankii]

Highly recommend getting a copy of the book - http://www.thedieselpage.com/62book.htm - and reading it cover to cover. That should answer most of the top questions. Then start reading through the forums. You'll be amazed at how much you learn!

[Blue66]

Thanks for he info guys. I'm going to do the fluids and filters today on it. Any ideas on the weight of the oil? I'll look for the "C" designation.

Should I fill the fuel filter with fuel before installing it on the truck. I'm assuming the fuel filter is on the firewall passenger side. I dont want to get air into the system, I've heard this is a pain.

The acceleration feels comparable to a stock 305 or 350, but I'm not worried about winning any races with it. As longs as it starts and runs well, I'm happy.

Thanks again:

-John

[john8662]

The common weight for year round use is 15w40.

[Subzilla]

The '83 should have 2 fuel filters - you saw the one on the firewall and there is also one under the air cleaner at the rear of the intake manifold. Don't panic, it's really not that difficult to change. Remove the fuel lines, then remove the 2 bolts holding the fuel filter housing to the intake and remove the whole assembly. Fill up this filter (and the bigger primary one) with fresh diesel fuel, then carefully replace everything in reverse. It should fire right up. I change mine at least once a year, takes less than an hour to do and have never airlocked the system.

Additional tidbit of info: If you have experience sudden power loss, surging, stalling, or hard starting (not your body but your vehicle), replace the fuel filters before assuming anything else. One bad batch of fuel can cause these symptoms. It just happened to me last month, I experienced multiple stalling after a fill up. I went home and changed the filters (which had not been changed in about a year) and it's purred like a kitten since. You should even carry a spare set of filters as part of your emergency kit.

[Blue66]

Thanks guys, you have all been a great resource to me. So far, I have about 2000 miles on it and am getting about 12 MPG w/ trailer, and 17.5 empty. It has never missed a beat, but does not like long hills...

Thanks

[moondoggie]

Good Day!

"It has never missed a beat, but does not like long hills..." Sure it does. It just likes to enjoy them a little longer than you do. :)

Blessings!