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bfaulkner
Senior Member

168 Posts

Posted - 09/14/2015 :  10:40:48 AM  Show Profile  Visit bfaulkner's Homepage  Reply with Quote
I'm glad you found your problem. what we have done for ours is buy 3 Maxi sized fuse holders and soldered them together and made out own harness. there are replacements from International that are basically the same but with slightly stronger pins in the connectors.
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aaronwilmoth80911
Top Member

538 Posts

Posted - 09/14/2015 :  11:07:48 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
Just an FYI, I know that one of those relays that is zip tied to the large harness is for the ECM. I've had an issue before where the bus wouldn't start and it was one of those relays. Just something to keep in the back of your mind for future reference.
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CISDbusman
Advanced Member

302 Posts

Posted - 09/15/2015 :  04:38:29 AM  Show Profile  Reply with Quote
Thank you both!!
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beaux.newlun
New Member

1 Posts

Posted - 12/07/2015 :  4:14:14 PM  Show Profile  Visit beaux.newlun's Homepage  Reply with Quote
Ive replaced fuel pumps and ipr sensors but I keep having same issues with atleast 3 different buses either a no start after getting warm or like its losing its prime all of them once you get running they run amazing its just getting them to restart im thinking high pressure oil manifold O-rings or (pucks) but im just wondering.
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JoeHEB1
Advanced Member

498 Posts

Posted - 12/08/2015 :  04:10:21 AM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
quote:
Originally posted by beaux.newlun

Ive replaced fuel pumps and ipr sensors but I keep having same issues with atleast 3 different buses either a no start after getting warm or like its losing its prime all of them once you get running they run amazing its just getting them to restart im thinking high pressure oil manifold O-rings or (pucks) but im just wondering.


Swap out HPOP with another bus and see if the problem moves to that bus. The last 2 I had with the same symptoms turned out to be the HPOP.
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aaronwilmoth80911
Top Member

538 Posts

Posted - 12/08/2015 :  04:19:52 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
Most of ours have been pucks when they have a hot, no start condition. Make sure to replace the o-ring for the oil manifold too. Or swap out HPOP like Joe said.
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1stLtDan
Active Member

USA
13 Posts

Posted - 12/07/2017 :  11:07:10 AM  Show Profile  Reply with Quote
If you have a scanner that reads the engine system while running, rule out fuel pressure issues by verifying fuel pressure while running. If that's fine - all good there. While reading fuel pressure shut off engine and turn key right back on and look to see how low the fuel pressure goes within 10 to 15 seconds. If fuel pressure drops to zero YOU have a fuel drain back problem. Usually a return fuel line check valve or the check valve inside the fuel filter housing. Point is with extended cranking the lift pump has to pull fuel from tank to fill filter housing and then high pressure fuel needs to pressurize fuel rail in order to even start. If pressure doesn't go anywhere close to zero and stays pressurized you have a different issue.
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CISDETC
New Member

6 Posts

Posted - 12/20/2017 :  05:45:25 AM  Show Profile  Visit CISDETC's Homepage  Reply with Quote
The biggest problem that I have had with this same issue is the o-ring between the oil rail "under valve cover" and the head. The oil passes through from head to rail under extreme pressure and the o-ring either blows out or dry rots and cracks with age. You must take the rail off to replace the o-ring so it is a cheap bit of insurance to replace the pucks as well just make sure that when you are putting the oil rail back on that the o-ring stays seated and the rail goes on flat as I have had the o-ring stick to the oil on the rail and get moved before tightening
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