12.7 Series 60 DDEC IV Valve Adjustment

[Glennman]

It seems like when there is one project or topic, that it turns into several. This time I'm planning to adjust the valves and injectors. I just ordered the depth rod and feeler gauges. I've been watching some youtube videos on the subject and am getting a little confused. One guy shows a page from the manual, and it shows that when you have the valves in overlap, say at cylinder #1, then you would adjust the valves there, and at the same time you would adjust the injector on #6, since they're both at top dead center. However, another video shows an excerpt from the manual, and it says when adjusting the valves on #1, then you adjust the injector at #5 (rather than #6). I know that 1 and 6 are always at top dead center together.

Short of purchasing the manuals (I suppose I need to), which one is correct? I know the second scenario (1, valves/5, injector) was specifically for the DDEC IV, but I don't know which engine the 1/6 video was.

Thanks for all the help!

[lhwood]

I have a manual dated July 2005 that has tuneup specs from 1986 DDEC I through 2003 DDEC IV It has the 1/5 indicated on the chart I've included.  Possibly the confusion comes from "Cyl 6 in overlap, adjust valves on Cyl 1 and set injector on Cyl 5".

Regards

[Glennman]

Thanks ihwood. That's one of the charts I've seen from a video that the guy said was a DDEC IV. I'll take that as a confirmation! That being said, the videos showed that "valve overlap" is when the exhaust valves are going up and the intake valves are going down at the same time (I could be getting the up and down backwards, but I think you get the idea). I plan on making those adjustments this weekend provided that my adjusting tools come in by then. If it works, I posted the chart that showed the 1/6 scenario. It's for the 12.7 G engine (I don't know the G is).

[luvrbus]

Thanks ihwood. That's one of the charts I've seen from a video that the guy said was a DDEC IV. I'll take that as a confirmation! That being said, the videos showed that "valve overlap" is when the exhaust valves are going up and the intake valves are going down at the same time (I could be getting the up and down backwards, but I think you get the idea). I plan on making those adjustments this weekend provided that my adjusting tools come in by then. If it works, I posted the chart that showed the 1/6 scenario. It's for the 12.7 G engine (I don't know the G is).

G is the standard 12.7  B is the premium model  60,I am sure you read where you bottom the injector out to 40 in foot pounds before using the gauge

[lhwood]

luvrbus is correct that a "G" in the 5th digit of the model number designates a standard engine as opposed to the "B" for premium.  I also have info in my service manual for the Series 60G.  Interestingly enough, it says the Series 60G is an alternate gas powered, spark ignition engine. The timing circle that I have for the 60G doesn't have the injector designations like your picture as the "gas" engine wouldn't have injectors.  I'm puzzled and curious...

Happy wrenching!

[Jim Blackwood]

luvrbus is correct that a "G" in the 5th digit of the model number designates a standard engine as opposed to the "B" for premium.

Must be the engine serial number, My VIN has a D.

Jim

[lhwood]

Must be the engine serial number, My VIN has a D.

Jim

He's referring to the engine model # not the bus VIN.

For grins and giggles I've attached the table that decodes the engine model number.