Noid93

I guessing if you had bad exhaust flex pipe, you have a bad pipe elsewhere. Its faily common to have leaks right by the heavy steel clamps that hold the pipe to the frame.

So you say

1) True

2) True

3) True

4) True

5) True

6) ??????

Any idea what the static timing is on a 454 or a 427? I do have a blixxton powerbox adding a little extra fuel to this thing, and would like to time it like a higher HP engine?

I guess I laid it out in that fashion, but no. I'm so curios as to the exact funcion of this thing, and the principles behind timing and smoke and a diesel engine.

i have seen alot of walking beams with missing bump stops. The front one especially would cause the issue you speak of. Usually if the U joints are being streched beyond their limit, you will see marks on the yokes where the yokes have been touching. If you have half round joints( two caps have caps on the end with hex bolt holding them, two caps are held in by straps with 12 point bolts), the 12 point bolts will have the heads smashed in some fasion. Each series of joints have a particular angle limits, but im guessing you have 1810 or maybe 1760 as an intermediate shaft and 23 -30 degrees is acceptable when your talking 13 to 18 inches center of joint to center of joint.

Check this out http://www2.dana.com/pdf/IJ900.pdf

Just had my Vmac II checked out for a few issues like a sticky rack, truck would kill at stop signs and cut out in the middle of a light or heavy pull.

Just got pump back, need to set timing, valve cover say 6 degrees BTDC #1. And im thinking, " if i set this thing at 6 degrees BTDC, it shouldnt smoke that bad at startup like the Vmac 1 & 2 do?" What does the 20 degree econovace on the Vmac 2 do exactly. Is it all advance or does it also retard timing

Follow me and reply to confirm or deny

1)More advance gives more time for a shot of diesel to burn in the cylinder, which equals less smoke, higher cylinder pressure, less bottom end feel(torque). TRUE/FALSE

2) Less advance gives you more smoke, lower cylinder pressure, bettter "seat of the pants" feel or torque, higher EGT due to unburt fuel and less air exchage (lower rpm generally) TRUE/FALSE

3) The mack Econovance system take oil pressure to advance the timing for a smooth idle? (this causes the smoke at startup?) TRUE/FALSE

4) The Econovance system only adds to the Advance(not retarding) of the pump, (6 degrees static plus 20 Econo = up to 26 degress in the proper situations) TRUE/FALSE if false, explain

5) The static time this pump to 6 degrees, is too shallow for a clean/smoke free start up and it requires more advance to run smooth at idle. TRUE/FALSE

6) If 5 is true, the econovance adds aprox _____? degrees of advance at idle?

Thanks in Econvance

NOID93

thats,,,very interesting,,,and good advise...bob

How bout a reputation bump mower man(i've never got one)....

Thanks Gentlemen

Overhauls are usually only required if the cylinder protrusion above the deck isnt high enough. Low cylinder height doesnt seal the head gasket properly, and can cause premature failure of head gasket. If you have good protrusion, good cross hatching on cylinder walls, throw two new heads on for good measure(yours are probably cracked anyway and the valves are tired and springs are weak), 6 injectors if they havent been serviced recently ($90 a pop, thats cheap) and a head gasket and out the door it goes for $6500 if done at a dealer. My 97 E7 had 780-820,000 miles on it when the head gasket went and i had $6200 into all this and a water pump. Cylinders were up, walls looked great, and it didnt use more than a gallon of oil on 10,000 miles. I got 860 on it now and i sure as hell dont regret not doing a full overhaul. When i priced an overhaul at the time i did the head gasket, it was $14-16,000. I saved $10,000. I belive that overhauls are only nessesary if you have failure in the cylinder, rods, or bearings. A bad head gasket only requires a gasket and heads as long as the cylinders have not settled. E7 engines that have been taken care of should go a million miles or more as long as there is no catastrophic failure elesware. Excessive blow by and oil consumption or traces of metals or soot in oil analysis a good indicator of tired rings i.e. cylinder packs.

Hope this helps

Your truck was built 9.25.96 and shows auxiliary shaft part number 453GC381M. You should be able to use shaft part number 453GC435M or 453GC435MX per SB 212-029. The parts system shows 453GC435M to be in stock.

It appears a new oil pump would be needed with this shaft also, based on an issue that these shafts had with oil pump drive gear..

http://hr.mckenzietank.com/maint/Bulletins/45-sb219009.pdf

I went ahead and had a keyway machined into it, and plan on using an extreem mating compound to mate the two parts together. There is still a very minor interference fit yet, so i belive this should hold. Im not a huge fan of welding a shaft that hard and tempered. One would think a keyway with a minor interferenc fit, plus the compound to keep the gear from walking off the shaft, and the air compressor coupler is right there, so it cant go anywhere..(i hope)

#5 wrecking yard?

Whats your VIN?

VIN 072852 - 97 CH613

I wont put a used shaft in for fear of this same scenario. Either way, if i cannot get a new one, i'm going to modify this, or another used one.

So, air compressor quits working the other night. Haul truck home, Did some reading her on BMT, tore into it today, and i have the same issue as gambi80 and others... Press fit shaft on the rear end of shaft has spun on the shaft. Here is the kicker, NO PARTS IN NORTH AMERICA OR WAIT TILL OCTOBER TO MFG MORE!!!! So i propose to you, what is the correct fix now;

1) Weld gear on the end of shaft

2) Half moon key shaft

3) Drill and tap a slot above key for set screw to prevent walking the gear off the end

3) Re-create tolerances like you would on a crankshaft(weld it up, grind it down)

4) Straight keyway

5) (place your idea here)

Any combo of the above?

Which bolts do i take out, the four that go in vertically on the block that attaches to the accesory drive? And i belive i need a gasket too?

Just reading some other econovance posts and i see there are some screens in the econovance block. My truck seems to take FOR EVER to clear up in the morning. Just replaced braided line that feeds oil to it. I am wondering if these screens could be the culprit. What is the original purpose for these, and is it possible that they are acting as an orfice and not imediately allowing oil to get to my econovance solenoid? Are there any reasons NOT to remove them? Please tell me more....

97 CH613 400(+30% w/ blixxton box),835K miles

My 97 does the same thing. All i do is make sure the wires going to the gas pedal have plenty of slack through out the entire movement of the accelorator pedal. Somehow the wires works themselves backwards through the wire saddle until its tight. Check the conector for corrosion and grease with dielectric grease and it should be good for a year or so....

I just installed a toggle switch (non oem) into the fan clutch override connector and hope that it doesnt effect any other operation. I tapped a switched 12v into the jumper(green) wire that came installed in it from factory. I want it to act just like the factory switch is in..... This is what i did. Is this how the oem switch works?... Or does it block the Control and only transmit 12 volt to the fan terminal when the switch is on?... and what is the "???" terminal for? If nothing else i could use a vin from a truck with an electric fan override switch. I did read where the fan should stay on for X amount of time after the override is shut off, and so far it does that.

It could be the large master solenoid/relay over in front of the passangers seat. Mine acts up once in a while doing similar things. i think its only twenty bucks right from mack. Don't replace it with anything eles. most solenoids are only momentary duty. this is a full duty solenoid

http://www.bigmacktrucks.com/index.php?showtopic=4365&view=&hl=trunion&fromsearch=

This will answer all your questions.

Easy ride height check-- Dump the air in the suspension when it is shaking. IF the shaking goes away, it is set to High(lower the susp. on leveling valve). If it doesn't go away, the ride height MAY NOT BE set high enough(if it is a driveline issue at all). Easy easy way to check for ride height isssue....

Easy task too. 5 or 6 bolts on the top of the head and pop the old parts out and new in. Thats about it. 20 min job for a first timer.

Does anybody know where to get a taller than 14 inch bumper. I looked and called a few places and 13 and 14 is the most common but i met a guy at an eathonal plant with a 18 inch chrome or stainless bumper. Cant find a name on it. Or a Manufacturer. Called a few places and "yes, we have 17 inch bumpers", drive there(with a tape measure) and its a 14 or 13. Any idea where to get a 17 or 18 inch tall bumper and actually HAS ONE at that height. Any help would be great...

Thanks

NOID

http://www.northeastfiberglassproducts.com...il2.asp?uid=146

this says 17... actually measured one, it was only a 14

Wonder if these are what they say also----

http://www.ds-sewing.com/truck_acc/bumpers/Mack_bumpers.html

http://southernstamping.com/mackbumpers.html

There is a "kick down" as well on the allisons. If u have an air throttle that moves a air cylinder on the injection pump, it uses the same air pressue pushing agianst a little cylinder and spring to move a linkage on the tranny to tell it how much throttle you are giving it. First thing, you need to find out if it is a cable modulator or air modulator.

If it is a cable modulator it can be adjusted if it is not broken. Remove the end from the transmission, which is located on the left hand side (in your case the passenger side) just above the top of the oil pan about 2/3 of the way back. There will be a pin inside. Have someone step on the throttle to see if the pin moves in and out with the throttle. The engine may have to be running to do this. If the cable is not broken, then locate where the cable attaches to the throttle linkage. At full throttle you should be able to pull the end of the modulator cable about 1/8" past the throttle linkage.

If you have an air modulator(located same spot) Remove the air cylinder. Apply shop air to the air inlet side of the air modulator. If any air leks by to the plunger side of the modulator, replace the modulator."

Hope that helps

I have a 97 that was doing the same thing, no overhaul though, and all it was, was the rubber hose on the breather tube/pipe had collaped, what little blowby i had, could not escape out the breather pipe. Instead, it pushed out the only other place it could, the dip stick tube. Not saying this is the problem, but i know i was relived when thats all it was on mine..

let us know what you find....

Curt

Manny, these trannys require very high and very low rpm shifts. Usually run the rpms up to 1800 in 1st gear pull it out of gear, and start pushing it into 2nd about 1300 rpm and it should fall in about 1250. You can damn near smoke an entire cigarette between gears. For down shifting, just the opposite. Run it down to 1200 and pull out of 5, rev it up to bout 1800, and slide it into 4. Best of luck.

I agree. You cant get boost without fire and damn good fire at that. If you are not getting lots of fresh air in (CHECK AIR FILTER..i know its simple but i've overlooked the simple things before myself) good MIST of fuel ( check injectors) at the RIGHT TIME (check fuel and valve timing), free flowing exhaust (check for back pressure, buildup in manifold, or manifold leaks). It seems like most the big problems can be a result of overlooking minor details.... I have also saw where the elbow that feeds filtered air to the turbo will collaps over the turbo inlet and block air from getting in, but only underload. Its hard to see the turbo underload so look for the possiblity of the elbow being soft, flimsy or push on it to see if it can even collaps that far.... Also i am not sure how the torque sensors work in the eaton fuller transmissions but if that is reading wrong, that may not apply full power. I have also heard of many electric throttle/foot pedals only giving the computer a reading of 50-75% throttle. When it is hooked up to the computer, check to see if the computer shows %100 throttle when you push it down. One poster said that a new throttle made his truck drive like a whole new truck...

PS Raf, if your turbo has a low bust, get it a pushup bra... Just kidding.... I saw the headline and laughed. I knew what u meant... boost

From what i have seen, the aftermarkets that bolt in are more than suffecient. When i do mechanic work for maxville during my slow times, I have seen him use them. I belive the first one he used was about 4-5 years ago and just as recent as 9 months ago. One on his personal tankers, and one on a log truck. Never had a problem with any of them and you can bet that a log truck, and for sure his slurry tankers see some of the hardest conditions possible. I would recommend the aftermarket for just the time savings and would sure have no problem trusting them as far as strength goes. Now obviously they have only been in his rigs for 5 years tops, but absolutey no cracks or breaks on the aftermarkets camelback trunions....