jzack

Had a new compressor installed in Feb. because of excessive oil in air system. Well it has been 4 mo. now and I still get a large puddle of oil under the air dryer (3" in dia.) after idling about 20 minutes. So, what should I look for now? Could this still be residual oil left in the system? I did change the cartridge once since the new compressor was put in at the dealer and the canister was full of oil. I check the tanks every once in a while and they have some moisture, but no signs of oil. This truck works every day so I guess I was expecting the the system to clean itself out by now. So I'm starting to think there could be another issue here. Anyone have an opinion and or experience with this problem? Thanks, Jeff

Thanks for the advice guys. I feel better about just leaving the extension on now. Keeps things cleaner. A catch can ain't a bad idea either, however I've never seen one on a big truck! The blow-by, while making a bigger mess than usual, isn't too bigga deal YET I think. Maybe one gallon every 4,000mi. I think I was told by a Mack mechanic once to do a rebuild once your in the one gallon for every 1,200mi. range. I'm gonna keep a close eye on it now though. Jeff

MY 94 E-7 with 913,000mi on original motor and turbo has been spitting a little more oil than usual out the breather messing up my tanks and stuff in only a couple days work. So I decided to add a 2ft. extension with a piece of radiator hose that slipped over the breather perfectly. Now just a week later, while setting my valves, a Mack mechanic with 20+ years experience told me I should get rid of the extension because the breather should never extend beyond the oil pan. If it does, he said crankcase pressure will be off and "stuff will wear out faster" in the motor. While I tend to trust a guy with so much experience, what he said just doesn't make sense to me. IMO as long as the size of the opening of the breather tube stays the same, the length of the tube shouldn't matter, right? Anybody have an opinion and/or experience with this? Thanks.

And on top of all that mess, here in Minnesota, a first year DOT audit is mandatory for any newly issued operating authority. Not sure about Jersey though.

I use Mystic, the red high-temp stuff on everything. Usually grease every 3 weaks to a month. 860,000 miles and haven't replaced a drive-train component yet! (knock on wood)

This is probably a long shot but have you checked to see that the air cleaner intake is properly aligned with the intake ducting on the hood? Mine was at least 3 inches off. After rotating the air canister for proper alignment my pyro was noticebly cooler. I also turned my intake louvers on the hood around to face forward for more of a "ram" air effect....every little bit helps. Getting your valves adjusted probably wouldn't hurt either if that was never done before, but that ain't cheap like the first two ideas.

Seen with my own eye's one of those new Fontaines, think it was a Phantom, with one of the beams snapped almost clean in half. The bottom flange gave away. The driver was pulling out of a building with a load of plate on and- BOOM!! Sounded like a pipe bomb going off. Guess the driver said this wasn't the first one in their fleet to do this! I always thought those new extruded aluminum beams looked too thin around the flange. The old welded style flange on my Raven's is much beefier. I suppose some engineer at Fontaine had a fancy "material analysis" computer program tell him that that beam would be strong enough. Computers just can't account for all the variables found out in the real world. 7,800# seems awfully light, even for aluminum. What kind of warranty do they offer?

I hear you there. Definitely slim pickens for flat-bed steel haulers. Many of the steel centers around here have their own company trucks so guess who's the odd man out.

Find a good Ravens and you'll be close to 30,000. I've owned a couple of them and pulled many other brands, but the Ravens are the best in my opinion. My current trailer is a 45'x 96" spread with duel tool boxes, 15" cross-members, and a lift-axle and weighs in at a feathery 8,300 lbs. Put a 52,000 pound coil in the middle of it and it still had some arch left! Too bad they got bought out by Fontaine who then pissed away all the great design knowledge that Ravens built up over the years.

Whats this "mystery oil" supposed to do? Wash out sludge or carbon build up? I've recently started adding Lucas every oil change based on knowledge from another owner/operater who used it religously. This guy amazingly got 1.6 million miles out of a 3406 Cat before his first rebuid! I was never much of a believer in oil additives either but Lucas seems like decent stuff. They claim it would work great for motors that sit a while between starts too.

It wouldn't hurt to have the valves done. Did mine at 500k and made a big difference in power and mileage. Should help the Jake too. BTW, I wouldn't doubt the previous owner, 32PSI boost is about right for a 427HP.

Maybe I'm different, but I'd rather have one of the last 1,000 than one of the first 1,000 off the line.

Gambi- you must have missed my posts from a few weeks ago. I had that same line go bad in my truck too! Took quite a while to track it down. Moist up at the head where you have to crawl up there and look straight down to see it.

Yes. I believe if you want mechanical you need to look at very early 90's. We even have a '93 E-7 thats electronic. I also think 400HP was the limit for factory mechanical E-7's. We actually owned five of the first generation electronic Mack E-7's ('93-'97) and found the system to be really reliable. All of the electronics are in the cab where they should be, and the system isn't overly complicated like their current abominations (thanks EPA).

Ya know I think the cable show "Myth Busters" tested that theory out in one of their episodes. They found that at freeway speeds they actually got better mileage with the windows up and the A/C on than with the windows all down. Of course in a big truck the variables would change a bit.......

Exactly.

I guess for the kind of work I do I can honestly say that yes I DO need AC up here in Minnesota. I drive a black day-cab -think "greenhouse". Most of my deliveries are local, I probably only average 35mph some days, not enough breeze to get the heat out. When I do get out of the truck I get to stand on a shiney aluminum flat-bed chaining and unchaining sheet metal -think "tanning bed". When I get back in my cab after a delivery I sometimes have 5-10 minutes of paperwork. So its just nice to have a place to work thats a few degrees cooler.

I also agree with you on the plastic leveler valve parts. Seems to me that parts on a truck that are moving all day long should be made out of metal and not plastic. I usually replace mine with stainless steel heim-joints found at the local hardware store. I for one though couldn't drive w/o AC. I have mine running from May through September! My older CH does have the vent in the door which I do use from time to time. Keeps the feet and legs nice and cool.

Well she fired right up Sunday night so I'm fairly certain the new return line was the fix. Thanks to all who contributed, it was greatly appreciated. Jeff

Reminds me of a quote I often heard from one of our O/O who's Mack lacked all the chrome "trinkets" always found on the Paccar's- "chrome don't get you home".

Well, I THINK I found my leak. I'll know for sure next time I let it sit for over 24hrs. I pressure washed the motor the other day to start out fresh and the next day I noticed a tiny bit of wetness around a fitting at the front of the head behind the waterpump (tough bugger to spot). It was the 3/16" fuel return line from the injectors back to the pump. The line looked to be all dry-rotted and practically desintegrated when I removed it. Went to Mack and got a new line and clamps and all was dry today. Fingers are crossed............

Thanks for your input HK. I'll check all my lines and filters to make sure they are tight this afternoon. The reason I've been focused on internal parts (check valve, seals) is because I've yet to see any wetness on lines or fittings. I figured if air is getting in that fuel would make its way out, but this is just my backyard mechanic logic. I've never worked on trucks for a living. Curiously, after replacing the plunger and check valve the problem did get better. Back to happening once a week rather than every day. So after replacing a part I would think its fixed until the next Monday morning rolls around and no fuel....argghhh!! I'm starting to think I should have just taken it to Mack in the first place rather than trouble shoot it on my own.....we'll see. Jeff

Well I've replaced the hand-pump and it still leaks down. Then I noticed when I prime with the hand pump I can hear fuel splashing back into the fuel tank. So I replaced the check-valve in the return line, but I am still getting leak down over a weekend. So Rob, now I'm thinking the next step would be the supply pump which I believe is what you were referring to in your last post, correct? If so, my dealer here told me there isn't a rebuild kit for my E-7 and a new one is about $200-300. Oh well.... Thanks, Jeff

I've seen a couple here in Minnesota. One looking pretty at the dealership in Roseville and another in the yard at Lefebvre in Elk River. The one at Lefebvre is interesting because they've run Petes and Kenworths for as long as I can remember. I couldn't help but think Mack would sell more of these if they would square off the hood in a retro/modern sort of way ala Mustang/Challenger, put a sleeper on it and rename it Superliner........lower price probably wouldn't hurt either. Haaaaah to dream.

What you described above sounds real similar to how my '94 CH 350 runs. The boost builds fast and peeks around 30lbs. while going through the gears (accelerating), but when I dip into the throttle at cruising speeds I can barely get 25lbs sometimes. Not sure why this is so. Maybe it is in the programming like fjh said. I am currently running the Blixxton box which has increased my peek boost (22lbs. to 32lbs.) but I still notice the variance. One other noticeable improvement with the Blixxton is better throttle response and lugging power in the lower RPMs. I believe the box fools the electronic nannies into providing full fuel in the lower RPM range. My pedal used to be dead between 1200 to 1400, now it feels like the pedal is connected directly to the pump if that makes sense. I know Blixxton only mentions E-7 300-400HP but the 427s and 460s all had the same pump so it may be worth a shot to give you a better torque rise in the lower RPMs. I've been running mine now everyday for a year and a half with no problems. There is a guy on BMT here who runs one on his 454HP and knows quite a bit about them........