Australian Hybrid Quantum Ea7 470 Valve Adjustment

[ciw65]

HHHHEEEEEELLLLLLLPPPP!!!! I have just done an in chassis rebuild on our only (thank God) Mack Quantum. An interesting vehicle. A Renault Cab-over and chassis with 24 volt electrics, combined with an EA7 470 ETECH ( with 12 volt electrics), 18 speed Road ranger and eaton diffs. Interesting in so much as the ABS system runs a 12 volt control module and 24 volt modulating valves. To say these things are a F*&^ up beyond all description is being polite. 5 hours to REMOVE the sump, and that is from Mack trucks job time schedule. The front crossmember has to be unbolted to access the 2 front sump nuts and allow enough room to remove said sump. The crossmember also has the front engine mount on it! Any wonder I drink! But I digress. My problem after doing an in chassis rebuild on this thing is I can't seem to get the valve adjustment right, even using the valve set marks on the flywheel. The engine is an EA7 which has the unit injector modules on the outside of the engine on the camshaft/exhaust side with injector lines running up to and into the heads. Any help or hints would be greatly appreciated as I am ready to burn this heap of @$$^#.

Edited February 18, 2008 by AusChris

[ciw65]

To all those who read my post and ran off scared, well done (these Quantums are a very scary thing). I have since found out that the exhaust cam lobe profile has been modified on post 1999 EA7 Etech engines. Turns out after re-doing the valve adjustment thanks to some VERY helpful information posted elsewhere in this section, the exhaust valve gap actually increases after you rotate the engine past the Valve set marks. I rang Mack trucks in Adelaide today after finding this and nearly tearing my hair out, to be told, " oh yeah, that's normal" I did question him about a 1/4" valve clearance being normal????? and he started on about modified lobe profiles, etc, etc. Why couldn't they tell me this last thursday when I rang??????? Oh the joy of it all.

[fjh]

To all those who read my post and ran off scared, well done (these Quantums are a very scary thing). I have since found out that the exhaust cam lobe profile has been modified on post 1999 EA7 Etech engines. Turns out after re-doing the valve adjustment thanks to some VERY helpful information posted elsewhere in this section, the exhaust valve gap actually increases after you rotate the engine past the Valve set marks. I rang Mack trucks in Adelaide today after finding this and nearly tearing my hair out, to be told, " oh yeah, that's normal" I did question him about a 1/4" valve clearance being normal????? and he started on about modified lobe profiles, etc, etc. Why couldn't they tell me this last thursday when I rang??????? Oh the joy of it all.

Chris if you had just run thru the valve set with out checking things (second guessing your self) you would have been just fine!

as long as the valvs are adjusted properly on the valve set marks what ever happens after that doesnt mater!just enlighten you a bit more ALL mack engines since the dynatard was invented are like that even the V8.

[ciw65]

Chris if you had just run thru the valve set with out checking things (second guessing your self) you would have been just fine!

as long as the valvs are adjusted properly on the valve set marks what ever happens after that doesnt mater!just enlighten you a bit more ALL mack engines since the dynatard was invented are like that even the V8.

Thanks for the heads up on that. I don't do a lot of Mack engine work, mainly Cummins and Cat, but my memory of doing valve adjustment on an old E7- 350 wasn't all that fresh. as for second guessing, sorry, but as a young apprentice with a very wise and knowlegable tradesman as my teacher many years ago, he drummed into me from day one, double check everything you do, it avoids reworks. So I always have. lack of experience on type is the key here I think. thanks for your input, cheers