300 tdi starting problem.

i need some help with starting issues, there's a short story of issues before this happened. struggling to get my head around it.

started cutting out when cruising with minimal throttle, then kept trying to stall when pulling away. turned out to be the sediment trap being full of sludge and what looks like sand mud compacted at the bottom. that cleaned and new fuel filter and the problem was cured.

since then it takes a lot of turning over to start, sounds like fuel is draining back. i don't actually think it is as even after leaving it 10 mins before re starting it does the same. spins over quick enough, so doubt it's hydraulicing, sprayed brake cleaner to find air leaks and can't find anything. tried a second hand lift pump (the one i took off and the replacement works by hand).

runs fine once started, so can't see there being a major issue so i must be missing something

any ideas and help much appreciated.

Sounds like air in the system or the lift pumps are nacked they are cr@p tbh, fuel line drawing in air possibly. I use outboard fuel primer bulbs to find leaks & bleed/prime fuel systems.
Did you replace the sedimenter seal.
Is there 2 seals in the filter housing.
Could try a outboard primer from a fuel can to the filter or work from the injection pump back to rule out pipes, filter,lift pump ect

Good luck.

300 tank sender pick up pipes rot out at the top allowing air in, access is under boot carpet, rmeove rear trim strip fold carpet forwards to expose round metal cover.

thanks for the replies.

i unscrewed the the filter this morning and was only 2/3 full, so diesel must be draining back.

i didn't have a new seal, will order one this week. this problem has started since i cleaned the sediment trap so am still thinking it must be something i've done. has the sediment trap got a one way valve in?

i'll have another look when i'm not working or baby sitting.

thanks for the help.

steve 379 said:

thanks for the replies.

i unscrewed the the filter this morning and was only 2/3 full, so diesel must be draining back.

i didn't have a new seal, will order one this week. this problem has started since i cleaned the sediment trap so am still thinking it must be something i've done. has the sediment trap got a one way valve in?

i'll have another look when i'm not working or baby sitting.

thanks for the help.

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The sediment trap belongs in the bin, its a good idea if cleaned often, but no one even knows its there so it gets ignored for years.

lynall said:

300 tank sender pick up pipes rot out at the top allowing air in, access is under boot carpet, remove rear trim strip fold carpet forwards to expose the rusty holed boot floor knock away the rmainin.

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lynall said:

The sediment trap belongs in the bin, its a good idea if cleaned often, but no one even knows its there so it gets ignored for years.

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Agreed !!!! ive got a new one fitted on my project but I just bypassed it