Changed fuel filter now hard to start?

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jayzc529
Posts: 91
Joined: Oct 31, 2006
Location: Dover, DE

Changed fuel filter now hard to start?

Post by jayzc529 »

Changed my fuel filter last night and now I must crank engine 7-10 seconds before it will start. Before you tell me that this is normal please realize that I am not speaking of the initial start up, this is still happening after about 100 miles worth of driving. Once it is started it runs beautifully. And if I turn off the engine and start it a few seconds later, it starts normally. But if it sits for 4 hours or so then it is a hard start. Ambient temperature has been above 50F for a few days here so temperature shouldn't be an issue.

Any suggestions are greatly appreciated.

Thanks,
Jay

P.S. There are no fuel leaks at the filter or anywhere else that I can see.
ISO_524td
Posts: 152
Joined: Jul 18, 2006
Location: Escondido, CA

Post by ISO_524td »

Did you damage the diesel fuel heating element when doing this? I've read in other places this malfunctioning is one cause of hard starting.

Also, did you purge the air from the lines after the fuel filter change?

Chris H.
Fimum Fit
Posts: 34
Joined: Mar 09, 2007

Check for very small leaks

Post by Fimum Fit »

which might allow air to seep in when the engine is off, and to be sucked in when it's running. The O-rings on the fuel preheat gadget are one possibility, and the copper rings on the bolts on top of the filter mount are another, and then there's the various seal points on the bottom -- the water separator and its drain valve.
Fimum Fit
Posts: 34
Joined: Mar 09, 2007

Another thing to check:

Post by Fimum Fit »

The box controlling the glow plugs is located near the filter and something could have been disturbed in the process of wrestling with the filter. Do your dash lights indicating "glow plugs working" and "OK, go ahead and crank it!" both work? The latter will cease lighting if even one glow plug is malfunctioning.

Numen tibi adsit.
jayzc529
Posts: 91
Joined: Oct 31, 2006
Location: Dover, DE

Post by jayzc529 »

Chris H.,
I don't believe that I damaged the element but it is certainly a possibility. Do you know what type of resistance readings I should be looking for to test it? And as for the bleeding of lines, I was under the impression that once you get it running consistently than there can be no air in the lines. Let me know.

Fimum Fit,
Glow plugs are working properly so they are not the issue. Water seperator is not the problem either. I took the plug loose and took that whole assembly out of the vehicle when I changed the filter. I didn't want to run the risk of cross threading while trying to screw it back on. It isn't leaking so I will assume it is fine. Will check the bolts on top tonight.
karl
Posts: 48
Joined: Feb 01, 2007
Location: mn

Post by karl »

You have an airleak and you are losing your prime. Just carefully retrace your steps andyou will find it.
jayzc529
Posts: 91
Joined: Oct 31, 2006
Location: Dover, DE

Post by jayzc529 »

Bleed fuel system and car is fine.

Thanks,
Jay
firefly
Posts: 2
Joined: Feb 11, 2007

Post by firefly »

My car had the same problem. The fuel line from the filter to the IP should be clear (or atleast transparent) hold a bright light up behind it and look for air bubbles going by as the car is running. There shouldn't be any. There shouldn't be a bubble in the line after it has sat for a while either.
On my car I was getting a leak from the black water sensing device on the bottom of the filter. When the fuel filter was replaced the O-ring was stuck to the old filter. No one caught this when it was being re-assembled and the symptoms are identical to yours.

If the car starts and you have driven that many miles bleeding the fuel system will not help.

I have also had similar starting problems when I developed a small leak from the injection return lines.
I didn't catch it until one day there was a big puddle of diesel under the car and it took much effort to start. Before that it was just hard to start in the mornings or after sitting a while.
David
Posts: 28
Joined: Apr 06, 2007

Post by David »

Hi,

I also have a starting problem, my symptoms are nearly the same as yours but.... When it’s warm it starts fine, but if it is shut of for a long time (4hours+) it’s sometimes hard to start (20 secs at least), and sometimes it starts right away, even in the morning after a long night.

When it starts hard it goes like this, I turn the key, it sounds like it fires up, and it goes dead, after that it is real hard to restart the engine, at least 15 seconds.

I’m suffering with this problem for a year or so, and I really want to get it fixed, any suggestions??

Thanks
Kyle in NO
Posts: 17638
Joined: Feb 12, 2006
Location: Nasty Orleans------> Batten-Rooehjch------>More Souther LA

Post by Kyle in NO »

Sounds like your glowplugs are not working correctly.
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