New to CUCV: Question about buying a truck: Diesel fuel leak

[GuySmiley]

I'm in the market for a good 'ol truck and came across one of these (I think it's M100 with 54k miles. There is a diesel fuel leak that seems to be with an injection rod or something. The seller said it was maybe o rings on this rod? He also says, it's hard to start the truck until it self primes itself because of this leak. He said that someone told him that if he let it warm up enough, the leak would stop.

Anyways, with the limited information I provided, does this sound like a familiar issue? My concern is what might be the repair costs on something like that. I'm going to look at the truck tomorrow with some cash in my pocket, but not completely sure what I might be getting into.

Is there anything else I should look out for? Is there a way to match the engine to the truck? The truck has lowish miles, but would like to make sure that it doesn't have a 500k mile engine in it.

Suggestions for a newb buying a CUCV?

Thanks!

 

[Triple C]

Well for starters, you do realize it is 24volt not 12 right? That is significant if your mechanical skills are - modest, as mine are. Second, that should be a 6.2 non turbo with low gearing so it has a slow top end. Now to the fuel leak. I have no idea what he means by an injector rod. There are steel lines running from the injector pump to each injector. If the line is leaking at the injector - tighten it up! If the line is cracked or the nut is stripped that is another issue. It may well be hard to start with a leak as that is a pressurized system. They are pretty good motors but I think it very unlikely that it would have 500k on it. I am assuming it is an 84-85? Surf for threads there are a ton of them about this truck. They cover mechanical as well as rust issues. Good luck and don't forget to post pics if you buy it! AND welcome to the site!

 

[cpf240]

If you read the stickies in the CUCV forum and go over the TMs, the 24v portion of the truck are not too bad to deal with. Only the starter and the glow plugs are using the 24v portion, the rest of the truck is 12v.

For the Injection Pump leak, he is probably talking about the throttle shaft seals, a common leak on these. The seals can be replaced, or have the whole IP rebuilt, which is what I would suggest.

 

[Skinny]

I agree, something that old I wouldn't think twice about replacing it. Even if you fix the leak the IP is probably old and will cause other issues down the road. New filter, new IP, new glow plugs, new fuel lines...good for another 50k to 100k miles.

 

[doghead]

$500 to rebuild the IP.

 

[GuySmiley]

Thanks everyone! Your info helps! Also.... what does IP stand for?


I'm hoping it'll be able to drive to my house. Not sure how bad the leak is or if that'll be possible.

 

[doghead]

IP = injection pump

 

[GuySmiley]

Gotcha, thanks!

 

[MarcusOReallyus]

Guy, one other thing to consider: Why do you want this thing? What are you going to do with it?

It's got low gearing, and realistically, your top speed is 50-55. You're in Tejas, which means a lot of wide open spaces, and people just don't do 55 on those highways. I know - I lived in Houston for a while. (Okay, some might say that's not really part of Texas anymore, but let's not go there, okay? )

It's a good heavy duty truck, but it's old, and There Will Be Maintenance! You'll probably need to replace a lot of rubber (hoses, belts, etc.), and it's no powerhouse and no speed demon. Wasn't built to be.

But it's fun, it's easy to work on, and it will carry some weight.

Hope that helps!

 

[markg]

How much does he want? does it have good batteries? start and stay running? sounds like the filter base is leaking fuel back to the tank. pictures and the vin would help. thanks. mark

 

[GuySmiley]

I'm just looking for a great truck within my price range. (about 3500 max) For trucks in that range, they're either salvage (if newer) or have tons of miles and rust (if older). Nearly 99% of trucks in my price range do not have air conditioning anyway, whether it came from the factory with it or not. I have a motorcycle, and a car that goes plenty fast, so I'm not missing speed, but it would be nice to go the speed limit, at least.

This truck seems like it has lots of potential. The seller says it has only a little surface rust, only 54k miles and the interior looks to be in good shape. I'll be going to look at the truck in person today.

I'm not specifically looking for M1008, I'm just looking for a good relatively strong, relatively economical truck.

Of course, the guy is asking more than I'd be willing to pay, so the deal may not work out. My max is about 3500 including the cost of replacing/rebuilding the injection pump and towing it to my house. Unless the flash of green bills sways his opinion, he may not let it go for what I'll offer, but we'll see.

Also, every vehicle I've owned has been cool in some way. This truck is obviously cool in it's own way.

So today, i'm looking at two trucks.

1. 1984 Chevrolet Silverado. Seller says has 105k miles with a 305 engine and 350 trans, cold AC and drives well with no body rust.
2. 1984 Chevrolet M1008. Sellers says has 54k miles, no rust and 4x4.

Which will be more economical? Which will likely need more repairs? Which will likely be more reliable?

 

[bigginstactical]

No offense intended but with your lack of knowledge going into this I'd say stick with the silverado. M1008 are cool and great rigs but will take a bit more research, especially when it comes to the electrical. If you are pretty savy with wiring then there shouldn't be a problem with a few hours or studying. If you are not and will be paying somone to work on it your repair bills will probably end up more then the rig. Any decent mechanic can work on the silverado..... M1008 is also easy but different. Like I said I would buy the silverado and later on down the road hop into the MV addiction. Or study up! read the WIKI a few times and skim all the posts about first time m series owners. Good luck and keep us posted. PS nothing happened if there are not pics to prove it.

 

[GuySmiley]

I'm no mechanic, but i'm quite confident in my abilities to learn, and have worked on a couple cars motorcycle in my time. No diesels, though. I don't expect the 24v electrical to be an issue.
Is it possible to find a service manual on this truck/engine combination? A military manual? I typically get one for every vehicle I've owned.

I did just get back from looking at the truck.......

It's definitely puking diesel. Think he said the fuel sending rod or something... can't believe I forgot already. The seller was saying it sends fuel back to the tank is why it's hard to start, but if it's sending diesel to the tank, it's also sending it every else. It was pretty significant leak, pooling near the IP, intake manifold and pouring on the ground. The guy said it should just be a couple O rings and a bushing and showed me a diagram and has the parts to fix it as far as he knows. Do I take his word for it? He seemed like an alright fellow... but then, the best salesmen do.
Looks like the rear differential seal needs replaced too.

For the price he's asking, he really likes the truck. Won't negotiate at all and is asking high dollar according to militarytrader website.

I like it though. Didn't buy the truck today. I'll crunch the numbers again, read few more things about these trucks, calculate known and likely expenses and maybe I'll make another offer another day, if he still has it.

The seller of the Silverado is out of town, so can't look at it today.

 

[doghead]

Manuals are free to downlod in our manuals section. Look at the top header of the page. Click "Technical Manuals" CUCV.

 

[GuySmiley]

Nice, good to know!

This is pretty active message board! That's good to know too.

 

[cpf240]

That sounds like a bigger leak than just the throttle shaft seals. It could very well be the fuel supply line that runs under the intake manifold, or a loose injector line. If it were me, and I liked the rest of the truck, I'd use the leak as a bargaining chip to lower the price, as I would expect to be sending the Injection Pump, IP, out for a rebuild.

 

[MarcusOReallyus]

I'm just looking for a truck within my price range. (about 3500 max) ...

I was in the same boat when I bought mine. I haul firewood on a regualr basis, as that's my only source of heat. Need to do various other hauling chores, too, from time to time. My witto bitty trucklet (Nissan) finally gave up the battle, after years of faithfully doing what no small truck should be asked to do.

I just thought I was getting a heavy duty truck. Found out I was getting a very cool piece of history. I like it!

... it would be nice to go the speed limit, at least.

That part ain't gonna happen without some modifications. Taller gears, an overdrive, a transmission swap, or other serous wrenching. It's been done, and many here can walk you through it, but it's not a "bolt up something on a Saturday afternoon" kind of thing.

Also, every vehicle I've owned has been cool in some way. This truck is obviously cool in it's own way.

Exactly.


But that Silverado is a solid truck.

Tough choice!

 

[Squid in a CUCV]

I found that my M1008 runs great at 60-65... A lot better than at 55. Then again, there seems to be a noticeable "dead spot" in the skinny at 55. lol

 

[Hasdrubal]

Your M1008 goes 65 with the stock 4.46 gears? Do you mean M1009?

 

[Squid in a CUCV]

Your M1008 goes 65 with the stock 4.46 gears? Do you mean M1009?

Yes sir! Stock M1008 But, not 4.46's... 4.56 gears. I drive 44 miles a day 6 days a week and 2/3rds of the trip is 60/65.