Good GPs, New Return Kit but misses on start and blue/white haze at idle - Diesel Forum

mhalter · 02-13-2008, 09:41 PM

I'm having some trouble with my 89 F250. Sometimes it will miss upon starting but sometimes it doesn't. Doesn't seem to matter if its warm or cold. I can start it in the morning for the first time and it will miss for a little bit then I can go where I'm going and shut it off for awhile and when I go back to start (sometimes 10 minutes later, sometimes an hour later) and it will miss for a little bit then too. And again, sometimes it doesn't miss at all. Also, sometimes when I start it up, let it warm up, then leave, when I get on the road and the RPMs start to rise, I get alot of blueish white smoke from the exhaust and it will go away within a half mile or so. Now I've noticed at idle I have a constant blueish/white haze coming from the exhaust, even when the engine is warm. No obvious coolant in the oil or vice versa ALTHOUGH I do see a drop or two of black oil on the top of the level of coolant in the radiator, but I've seen this ever since I've owned it.

What i've done so far:
New return kit 6 months ago with no visible leaks around the leak-off tees. All glow plugs test good. Changed the fuel filter and oil and filter.

I'm thinking possibly I have an injector starting to go bad? Or maybe the injection pump could be getting weak. I'm hoping I don't hear that bad C word. I have maintained the coolant additive since I've had it, but then again it was 13 or so years old when I bought it...

suv7734 · 02-13-2008, 11:48 PM

Have a close look around the header for the fuel filter/separator. Since the introduction of the ULSD fuel there are a lot of people finding the o-rings for the fuel heater are leaking which will introduce air to the system. It may not be a big fuel leak but it will be an air leak when the engine is shut down and it is at the highest physical point of the fuel system.

cdnsarguy · 02-14-2008, 12:14 AM

Check out........ Ford diesel 6.9 7.3 IDI look for the filter air leak info...

Since you replaced the return lines, I would also check and ensure ALL caps are sealed correctly. Some will work themselves up on the orings and allow air to enter the system..... Blue smoke and surging rough running are some of the symptoms.

Gently but firmly push the caps down on each injector once more..... DO NOT use the line nipple, use the round body of the cap for leverage area.

bentmettle · 02-14-2008, 12:30 AM

Quote:

Originally Posted by suv7734

Have a close look around the header for the fuel filter/separator. Since the introduction of the ULSD fuel there are a lot of people finding the o-rings for the fuel heater are leaking which will introduce air to the system. It may not be a big fuel leak but it will be an air leak when the engine is shut down and it is at the highest physical point of the fuel system.

thanks for posting this- I'm struggling with getting my van to start reliably. I'd also replaced the return lines/caps 2 summers ago, and it ran fairly well for quite a while. It's gotten progressively more difficult to start, hot or cold, and acted like it wasn't getting fuel. The timing certainly seems to correspond to the fuel formulation change. Once it's started, it runs fine, but man the starting process is a bear.

cdnsarguy · 02-14-2008, 12:37 AM

Starting procedure has a lot to do with it also........ Good batteries and a very fast starter are a must.......

Snotzalot · 02-14-2008, 06:52 AM

Quote:

Originally Posted by cdnsarguy

Starting procedure has a lot to do with it also........ Good batteries and a very fast starter are a must.......

Exactly! Since I did the return lines, replaced the starter, GP's, alternator and batteries this past summer, I don't even plug in in anymore. My usual starting temp is about 20 degs F.