Do you think I need a fuel filter?

Howdy, yesterday I put over a half tank of biodiesel in my 300tdi and today it wouldn't start. I steered clear of using bio during the extreme cold weather we had as even the mineral diesel from shell etc wasn't able to cope with that.

Because the engine was turning over and the battery was fine I thought that it must not be getting fuel and that perhaps the filter was blocked or the bio diesel had gelled (despite the guy telling me it has additives to keep it alright down to minus 12 and it being reasonably mild this morning), so I put a kettle of boiling water over the filter and injector pipes and sure enough the engine started. I revved the balls off it to clear out the fuel that would have been being pulled through on my unsuccessful start attempts but when I took my foot off the gas it cut out. I started the engine again and it was back to normal.

So I'm going to see what happens tomorrow morning and see if it's cleared up but do you reckon that the fuel filter may need changed again? It wasn't done that long ago (august) but with me using bio a couple of times since then and it supposed to be detergent maybe some crap has been pulled through the system.

I'd change the filter again and clean the sedimenter, where did the bio come from? is it from a reputable production company? I personally wouldn't trust bio from anyone source I didn't know very well.
Oh and if it's still gelling throw a couple of litres of unleaded in there anorl.

They seem legit, they had a queue of people waiting for fuel when I was in yesterday including work vans etc. So I'm fairly confident their fuel is good n clean, which makes me think it is the crap being pulled through the system with the combination of a ****part filter that's caused the problem.

fair enough, defo change the filter then and see what happens.

Next time you buy their fuel,put a sample in a clean glass jar,and add an equal volume clean water ,put the lid on and shake the nuts out of it and let it settle-the bio will look like orange juice,this is normal-the water underneath is what you are interested in-it should be crystal clear-any milkyness is soap,and this soap will block your filter-also the interface between the bio and water should be a clean division with no third layer-this is a simple test for soap in bio

Normally when you first add bio to a previous derv run engine,you can expect to change the filter after around 1000 miles(if at all)-never known the next day!

biolandy said:

Normally when you first add bio to a previous derv run engine,you can expect to change the filter after around 1000 miles(if at all)-never known the next day!

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he said he'd used bio a couple of times since the last filter change so it may be a build up of crap. there are too many people at the moment selling "bio" from the backs of vans etc. All a bit dodgy if you ask me.

Doesn't indicate his location,might be really cold where he is.Down South here it is too warm for waxing unless the guy has made bio from palm oil,which is really a summer only fuel

I would never use palm oil, that stuff goes solid and the merest hint of cold

I live near Glasgow, it has been cold but last night and this morning was more mild. I might just have been putting two and two together to get five but the boiling water over the filter and injectors did get the car started. I'll see what happens tomorrow morning and regardless I'll change the filter again as it's recommended you do so after your first couple of tanks of bio.

Right two problems now that will be sorted as soon as (poorness isn't helping) engine cut out twice today but started immediately, was braking from highish speed and the engine just stopped. It was a bit worrying but went round and spoke to my mechanic and he suggested fuel filter before I went into details. But I think the real root of the trouble starting is the battery so I'll change both in the next week or so.

Going to completely break the bank and spend the extra £3 getting a bosch filter or something instead of a ****part one.

Ive done 7000 miles on 100% bio and have only changed the filter once after 1000 miles and that was a britpart one, I have had no troubles. I just added a gallon of unleaded to a tank of bio back in Dec when we had the snow.

horse62 said:

Ive done 7000 miles on 100% bio and have only changed the filter once after 1000 miles and that was a britpart one, I have had no troubles. I just added a gallon of unleaded to a tank of bio back in Dec when we had the snow.

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This would be my first change so I hope my experiences turn out similar to yours.

If the bio is good and clean and soap free,after the first extra change(doesn't always happen,but can do).You should then be back to normal ie once a year on regular service,or however often your regular service is

An update. Got a new battery and fuel filter in it last Friday. It's been going great, starting first time no problem until today. Last night was the first time for a while we've had a thick frost so was the first test really since I fixed it.

Gave it the normal heat and tried to start it to no avail, tried letting the glow plugs do their thing another twice and tried again, still no joy. So put a kettle of boiling water over the filter/ injector pipes etc and tried again, still no joy. Waited a few minutes more, and tried starting it pumping the accelerator rather than just holding it down a little, got it started, obviously a wee bit of smoke starting and as I accelerated away but fine after.

So what I've learned with this experience is, that the bio I've been using probably isn't worth using (for me anyway) while it's still cold out. Also that my last battery was goosed because it would turn over the engine with more of a wooomp woooomp sound rather than a doodooodooo sound if that makes sense also after the first failed starting attempt I would have need a jump start on the last battery and the new one didn't flake out at all.

Have you tried not touching the accelerator when starting? I was always told not to press it at all when starting a diesel. I'm sure the boffins will be here soon to tell you why/how etc.

barmatt said:

Have you tried not touching the accelerator when starting? I was always told not to press it at all when starting a diesel. I'm sure the boffins will be here soon to tell you why/how etc.

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The first couple of attempts I didn't touch it.

I imagine the scenario here is fuel is becoming too thick, not flowing and therefore starving the engine. So flooding it and having the excess fuel burn off as black smoke is preferable to not going anywhere.

I put half a tank of regular mineral diesel in it today though as it was nearly empty of bio and I'll see how it goes. I think I'll stay off the bio until the weather is better and the temperatures come up another couple of degrees.

I've just put a load of locally, but professionally ,made bio diesel in my 300tdi Discovery. (Pure Fuels, N17)

Now that the normal diesel that was in there seems to have been used up it's proving to be a swine to start in the morning.
I thought it was the cold weather last week but this morning it was reasonably warm and I used the glow plugs 4 times then turned her over and had to keep the starter cranking for about 40 seconds before she chugged into life and blew out a load of black smoke which quickly cleared.
Once up and running she drives perfectly and once warm starts on the button.
I have only done 120 miles on the bio diesel and didn't change the filter before hand.
Any suggestions/thoughts?
I suspect the filter change will be number one on the list!!

Thanks
Jon

Change the filter 3 or 4 times the first 1000 miles.

storm99 said:

Change the filter 3 or 4 times the first 1000 miles.

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wot he ^^^^^ said,

buy yourself half a dozen filters they work out a lot cheaper that way, always handy to have a spare in the boot.