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Just a few q's about diesel's

Jan 19, 2010
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West Midz
Right then, a friend of the family has asked me to do a full service on her, diesel nissan primera (it hasnt been serviced for about 2 n half years she said lol). However i have a few questions about car diesel engines.

1) I used to work on commercial vehicles (havent for about 2 years now, so please bare with me). I used to fill the new diesel filter up with diesel before refitting it, does this apply for diesel filters on cars?

2) Whats a good resistance for the glow plugs? I will more than likely end up changing them anyways, but its good to know.

I cant think of any more questions at the moment, but im sure i will think of one or two later on.

As usual, any help is much appreciated guys. Thank you.
yes and not sure but after two and a half years he replace them anyway. For specific resistance id check the owners manual
I'd get the fuel filter as full as you can before fitting, unless it has a primer head ?
well to be honest, ive never filled the filter on mine, needs a bit of cranking adn revving for the first 30 seconds or so but afteer that its fine. the astra diesels have self bleeding fuel systems
Always bleed diesel fuel filters, if you don't it can sometimes take a long time to get it started again. Ford diesels are the worst for it!

I'd leave the glow plugs, if it's starting fine then no need to replace them. They're not like spark plugs where they're going to affect driveability.
Thanks for the replies.

How do i bleed the fuel filter? I know on vans (sprinter ones) they do have a bleed screw on them, its in amognst the pipes running to it. Would it be the same on a diesel car? Sorry for the q's but ive never worked on a diesel car, only on vans and lorries.

Whats a primer head?
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Button on top of the filter casing, it pulls diesel up and into the filter whilst pushing air out.

From what I remembered from college the primera DOES have one of these, however you'd still be better off topping it up with Diesel and then priming it out again.
Common rail diesels are direct injection, they have a lpp in tank and hpp at engine. You should not require to fill filter up on modern cars. On older cars with primers it is a good idea to stop it airlocking in the lines, making it harder to draw up from the tank.
how to check your glow plugs

1. take each glow plug out
2.connect a positive jump lead to a battery
3.connect the other end of the positive lead to the top end of the glow plug abd count to 10 and it should be glowing red in under 10 and any longer than 10 replace them
on my 306 a good glow plug was pulling 16 maps if iremember right. never needed to take them out, just took off the power rail off the top and went straight from the battery to the top of the plug with voltmeter.

i always fill the fuel fileter on a diesel, some cars are a ******* to start if not!

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