JoeH

But your oil is running hot too, so the engines gotta be overheating.

I suppose it also depends where your water temp sensor is mounted. Usually they're near the thermostat? But if Volvo was dumb enough to put it by whatever circuit you've stumbled on it could be reading hot there even though the main water jacket itself is at normal temp?

Not familiar with the MP engines, but the engine coolant is through the upper and lower rad hoses, which you'd have to try pretty hard to plug up. If the fitting you mentioned is clogged up it may indicate a sludge problem that could be clogging up your radiator core internally, not allowing enough coolant through to cool the engine when working hard.

It's pulling some air through. Can you set the idle in high in neutral using the cruise? It won't suck your hand hard, but it does need air flow. Just blow air through from the fan side with compressed air. It'll tell you real fast how much dust there is in there. Blow out as much of the radiator as you can this way before tearing things off. Get what you can out of there that way and run it for a day, see if it's any better.

And I call BS on that taking 2.5+ hours to change out that elbow. It's two V clamps and you're cruising.

Part of the reason some of us run old dogs. They cost a fraction, and don't have engineering defects that haven't been addressed yet. Volvo got your money, they don't care about you now. They'll wait for a customer to engineer the fix, void that customers warranty, call the fix their own and put it on everyone else's truck. Meanwhile you're stuck with a truck you can't use but still have to pay for.

Throw a patch on, run it. When they say they have a fix put the broken POS back on there and they won't know the difference.

Blow from the fan side out towards the front with compressed air. How is your air filter gauge? Is your air filter clogging? That'll run your pyrometer up.

How many tons of payload does the pup trailer setup get you?

Find a local commercial agent that can shop around for you.

Ouch! 21k?? What are you hauling?? I paid 11k/year to haul fuel oil, and that carries a high general liability. If you're new to trucking I'd walk away if you can't find something wayyyy lower. Can't make money with a 21k policy. If you're going to make a living with your driver's license you need to keep it spotless. Hind sight is 20/20.

That sounds like it's time for rings. My trucks sit on people's driveways a lot, I can't be leaking that kind of oil.

Kinda hard to see, but I'd probably try and fudge some flex pipe in there... Sux to have such a new truck do this; hope it doesn't void any warranty by patching your own fix on there till mack figures their sht out.

How much pressure is the turbo putting to the intake manifold? If the DOT is that fussy that they're nitpicking s little blowby residue then wash the engine once in a while. In the 11 years I've been driving I've been pulled over twice in my dad's fleet. They're usually just checking brake adjustments and obvious things. Once they mentioned oil leaks, commenting that it'll deteriorate rubber hoses. It was more of a helpful/instructional comment than an "I'm gonna slap a big fine on you" comment.

Miles? Hours? I'd keep oil in it and keep on running it. You could run a compression test to see if the piston rings aren't sealing so we'll. Other culprit could be worn valve guides?

You can convert over to 12v batteries; real easy. Just put the positives on same side and jump them together, and negatives same deal. Instead of POS to NEG jumper. You'll need to trace across left battery box to right to make sure you aren't doing anything goofy like wiring it up to 24v.

I use either a strap style filter wrench or the right size metal band style. Both of mine hook up to ratchets, so with an extension you are all set. Come in from between the spring and the frame with the wrench. Turning the wheel helps get a better attack angle. Filter goes out the bottom, it's a bit of a leap frog scenario to get it down and out below the spring.

Keeping a semi active military keeps soldiers trained, keeps research happening. If we sat on our doorstep and waited for someone to attack us we might get soft before it happens. I'm not saying I support one way or the other, but we are the strongest country in the world, and have been for a long time, and there's reasons for that. Yes in ww I and ww ii we rose to the occasion from a passive state, but that might not always work.

Idle should be set to 650. Surging could be weak idle governor springs?

The 5 speeds top out at a direct 1:1 ratio I believe. Other transmissions have overdrive, sometimes in the range of .6:1 or .7:1.

It turns over but won't crank? Cranking and turning over are the same thing, only difference being one can be done by hand, the other by starter motor. Are you turning it over by hand to make sure it's not seized, but the starter motor won't turn it? Or is the starter motor cranking it but it won't start? One scenario indicates an electrical problem with your starter motor circuitry, the other indicates that you aren't getting fuel. Have you pushed the stop knob in to allow the fuel pump to send fuel to the injectors? If it doesn't have a stop knob, you need to determine what the mechanism is that shuts fuel off on the pump and test it.

Puff limiter circuit? Mack uses boost pressure to dictate how much fuel to let the engine have so you aren't "rolling coal." Doesn't look like the normal position for the puff limiter though, that's typically a slave cylinder on the front of the fuel pump I think? Someone with more knowledge ought to pipe in soon...

The guys here are a huge resource, but for doing detail work you have to have the book. You need to know torque settings and step by step procedures.

Yep; a little supervision from my dad. (helps to have someone help pour paint for refills) I like to have the cab stripped down as much as possible to paint. Lights, horns, mirrors, roof vent... I want it all off. Hood is off right now, dad's gonna repair the fiberglass cracks and we'll sand it down and paint it before it goes on. What are you looking for in paint for your 79? I like to dredge up winter work to keep a cash flow in our off season.

Go to your local Mack dealer and buy book # 5-106. It's the E-tech Engine Service Manual. While you are there buy book # 8-211, it's the v-mac III service manual. Contains every code and the diagnostics to find the fault. Those motors contain a blink code system to read active fault codes. Between those books you should have everything you need to tackle just about any issue you have with the engine. Great life out of your existing eups! Pictures please! EUPs tend to fail from either broken springs or an alignment dowel breaks, allowing the EUP roller to rotate, eating the lobe off the camshaft. Replacing the alignment dowels is a good idea. I've never had to touch an EUP though, so I'm just reciting what I've read here.