Leave the unit pump wires hooked up and try cracking the injector lines 1 at a time to try and locate.  My guess is you have a bad eup and it's not supplying enough fuel for the new injectors.

Also like Jojo said, we had a plastic liner that goes into the top of a pop bottle get drop in a tank, took forever to figure that one out.

Just had a 94 300 mechanical that we chased an air issue for 2 years, and finally found a tiny Crack in the filter housing.  Had the filter housing off of it a few times and didn't catch it till the last time.  Fires off fast now and runs like a champ.

We have a 2001 350, and when the "chirp" as we call it starts its a matter of time until a new cam.

3 minutes ago, OldRedMack said:

If your looking to go above the 400, they are probably looking for the 419m3 and 1868 nozzle tips

I would start with the thermostat.  

I am sorry if I'm highjacking this thread, but this makes me think of a question I've had for a long time.  On the AC motors like this one, could you get a ECU and VCU off of an AI engine and just put a regular turbo on the truck?  Or am I way off base with that?

Have you pressure checked the intake?  Someone correct me if I'm wrong, but if you have an intake manifold gasket leak and the engine is not reading enough boost/intake air pressure, then it will not supply enough fuel.

On 12/30/2020 at 6:18 AM, Bubba Rick said:

Davco coolant lines disconnected. Water filter replaced. Bad lines replaced. (Bunk hard lines on order) . NO MORE COOLANT LOSS! NO MORE CONTAMINATION! 

Bunch of little things added up...

Bad connection to VGT took care of that issue too. Still misses occasionally and code for #3 injector, but with 890k, probably could use a set. 

THANK YOU! 

The injectors really aren't that expensive,  but where they get you is with eups. When/if you change injectors be prepared for some weak unit pumps.

On 10/18/2020 at 1:08 PM, alex g said:

Haven't gotten to the bottom of this problem but I was told yesterday my steering pump which is a Luk brand has issues with bypassing. This could cause the noise. I have to get a pressure gauge on it to see if that's the problem but the place to test it is a couple hours away and until I have work in that direction it can wait. I'll update this when I get to that point.

Did you check the power steering fluid level?  Mine will hum if fluid level gets low.  Though that's usually only when turning.

I see a reason not to run the super singles, you can get home on just 1 of the duals.

So its an external egr?  That would be an AC engine.  Different than the AI engines with internal egr.  Mack had 2 different versions of engines, so need to know if its a AC460 or AI460.  

Yes and no.  Mine shifts easier at those higher rpm, but when you get use to it you will probably start shifting around 1750-1800.  The hardest part for me was getting use to how touchy the electronic pedal is on the macks.

Pressure check the intake.

If its a 1999, it is not an mp7.  Should be an e7.  

Could be the elephant pads already, I really only get about 2 years out of them.

Any news on the 2nd switchblade?

Buy a new set of injectors, they aren't really expensive.  Its been a couple years since I bought any, but they were $85.00 a piece plus core charge that you get back.

Check the bolt on the output yoke of the transmission,  mine gets loose about every 3years and acts like that.  Doesn't matter how much loctite and torque, it still works loose. 

Definitely pressure check the intake manifold.

Have you checked the coolant level in reservoir tank?

4 hours ago, 41chevy said:

 

Donate

 

 

 

Maine Public Radio

Mills Administration Updates COVID-19 Prevention Checklists For Food Businesses

By Patty Wight • Aug 14, 2020

 

Most of the updates are just a few additions or clarifications to previously released checklists.

For example, front-of-house staff in restaurants, convenience stores and fast food businesses  who choose to wear face shields must now wear them upside down so that they are attached at the collar instead of the forehead, so that their breath is directed up, not down.

 

I might be an idiot, but is this for real?

The bags deflating overnight is nothing to worry about.  What suspension does the truck have, are there flat spots on the tires, how long is it?  We have 2 trucks with 44s and the 1 that is about 18" longer rides great, the other shorter truck empty feels like a bucking bronco.

I can't imagine the things you have seen on that plane.  Just awesome.