Author Topic: Cat c7 330 hp will not start  (Read 340 times)

0 Members and 1 Guest are viewing this topic.

Offline stoneinhi

  • Newbie
  • *
  • Posts: 3
Cat c7 330 hp will not start
« on: September 26, 2019, 08:30:18 AM »
Probably not a new topic but I didn't find any insights on other posts.  2003 Allegro Bus on Freightliner chassis.  Cat C7 330 hp engine.  Started fine before Labor Day.  Backed out of drive turned around and backed back in.  No issues. Shut it diwn,  came back to it on Tuesday morning it cranked freely but would not start.  Changed the one fuel filter that I can find.  Filled the filter with fuel before installing.   Still no start.  No check engine light except for the key on test. Odometer is flashing 1888888888.  It did start and run briefly on a shot of ether into the intake.   The local cat shop doesn't have a mobile repair service.   

Offline David.e.atherton

  • Global Moderator
  • Sr. Member
  • *****
  • Posts: 267
Re: Cat c7 330 hp will not start
« Reply #1 on: September 26, 2019, 12:10:19 PM »
Hi, let’s start with the simple thing first. The milage numbers all 888888’s first lead me to
The gauges on your dash panel. First thing you need to do is unplug the circuit board
that all your gauges  connected, think plug may be in center of back of housing that contains
all panel gauges if air in center it’s at the outer side. May want to call the builder and ask them
for sure but think it easy to see plug. Unplug for few minutes and put plug back in. What
you are doing is resetting the gauges that also affect the starting.  Next place to look on
Electrical panel look for fuse marked IGN  power, and ECM power.  That does not work
Let me know. Any time with a electronic engine use of starting fluid unless trained mechanic
Can do damage to your engine. First with engine heater and starting fluid settling in the
bottom of Charged Air Cooler. The sudden start puts engine rpm at beyond rated rpm
( engine run away number one and number two shearing of key on the cam shaft gear ).
If key shears on cam shaft will put valve train out of time and will destroy your engine .
What you have told me and you are lucky engine would not start without aid of starting
fluid and stay running. Which leads us in direction no power to the engine ECM that
Powers up the injectors with high pressure oil from  Heui pump.
Ask Dave , Dave Atherton Retired Cat Mechanic

Offline stoneinhi

  • Newbie
  • *
  • Posts: 3
Re: Cat c7 330 hp will not start
« Reply #2 on: October 17, 2019, 03:43:52 PM »
Thank you.  I know very well that starting fluid is not a good idea on modern engines.  I would not have tried it except it was recommended by Freightliner.  I also tried the solution i read elsewhere by disconnecting the injector pressure sensor with no start.  I will try your suggestion as soon as I get an opportunity.  Lots of running around and going to occupational therapy for a broken elbow. 

Do you know a mobile cat tech in the Beaufort Hilton head South Carolina area?  I just would prefer to not tow it to the nearest cat shop.

Offline David.e.atherton

  • Global Moderator
  • Sr. Member
  • *****
  • Posts: 267
Re: Cat c7 330 hp will not start
« Reply #3 on: October 19, 2019, 04:11:15 AM »
Stoneinhi, try on thing disconnect the Injection Actuation Pressure Sensor, location directly
across the Heui pump top and on engine block ( has a looks mushroom head with a pig tail
Wire about 12 inches long that clips into wire harness harness triangle looking connection.
Disconnect wth IAP connection from wire harness and try to start engine if engine starts
the IAP Sensor is bad needs to be replaced.  Ask Dave , Dave Atherton Retired Cat Mechanic
 

Offline stoneinhi

  • Newbie
  • *
  • Posts: 3
Re: Cat c7 330 hp will not start
« Reply #4 on: October 23, 2019, 07:55:47 AM »
Dave,
Thanks for the suggestions.  I tried disconnecting the Injector pressure sensor and all of the connections that I could find on the back of the instrument panel.  located 2 additional fuse and relay blocks and tested all the fuses and felt all of the ignition related relays change state when the key was cycled.  Any additional suggestions before I suck it up and call a wrecker to take it to Cat.  No mobile Cat service techs in this area that I can find.  I have electronics experience and a digital meter.  LOL.  I keep getting suggestions from people on the Allegro Classics Facebook to loosen an injector line and see if I get fuel but I don't think that would apply to the CAT.