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Engine Specific Info and Questions => IDI Engine => Topic started by: Dr. Diesel on January 12, 2005, 06:22:06 am
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a little tidbit for your troubleshooting files.
Freshly overhauled MF engine, new injectors. Started great cold, drove fine. Shut it off hot and try to start it 2-20 mins later, no go.
Injection and cam timing was good, compression was 490 across all four, no evidence of fuel drainback. Fuel shutoff solenoid was changed with a known good unit. (even though it wasn't really a suspect)
Changed the pump to a known good one, and the problem disappeared.
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The pump head/rotor was probably worn. When the engine was hot the fuel viscosity was low and it was leaking past the injection pump head/rotor interface fast enough that the pump could not develop enough pressure to open an injector. This only happens at cranking speeds, at running speeds there isn't enough time for significant leakage so the engine runs fine. When the engine is cold the fuel viscosity is high, head rotor leakage is reduced and it starts fine.
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I figured it had to be something like that... In an odd way, it was a refreshing change of pace, having a diesel not start cuz it was hot! :roll: :lol:
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DD, how many miles on the suspect pump?
In retrospect, my previous 87TD did the same thing years ago, QuickTD suggested the same thing, and I'm certain he was right.
I had 370k km on the car. Didn't have an easy life either...
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unknown history on the suspect pump. likely a little over 300,000km