250td o ring seals,question please?

laurence

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Hi All,
hope you can help me,have started to replace the o rings on my 98 202 2.5 td because it's been a bugger to start last few cold mornings.Have done 3 on top the filter,1 at the back and 2 just below.There are 2 different sizes as a point of interest and found 1 seal very square which would let in the air,causing the problem?Anyway have tried to do the 2 underneath and given up for now (need to use a ramp I think?).Just as a point have changed fiter and pre-filter a couple of weeks ago.Question how many in total are there so I don't have to strip too much of engine accessories in my hunt the rest.Will let you know if starting issues have been sorted,regardless.So far it's been very easy,just need a small screwdriver to take old seals off.Could do with a gynacolagist though, to change the bottom ones,if there is anyone out there please?
kind regards
Laurence
 

turbopete

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i have an e300td which is a similar set up, and from memory (im not with the car at the moment) there are 12 on the plastic fuel lines (including pre filter 'o' rings) 1 behind the shut off valve and 2 on the fuel filter mounting 'bolt'. also do check the small braided 'leak off' pipes that run between the injectors, and to the return line, and the end blanking plug as ive known leaks in these cause starting problems.
 

roadhog

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TP, explain how the 'leak off' pipes cause starting problem please. I may be wrong but I was under the impression that they're just return lines for fuel not used by the injectors. I had a couple of them leak when I first got my car but never had any starting problems. Just curious. :)
 

Iain the gadget

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TP, explain how the 'leak off' pipes cause starting problem please. I may be wrong but I was under the impression that they're just return lines for fuel not used by the injectors. I had a couple of them leak when I first got my car but never had any starting problems. Just curious. :)

They let air into the system which for a diesel is a nightmare scenario.
 

Iain the gadget

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W208 230CLK W163 ML270cdi
i have an e300td which is a similar set up, and from memory (im not with the car at the moment) there are 12 on the plastic fuel lines (including pre filter 'o' rings) 1 behind the shut off valve and 2 on the fuel filter mounting 'bolt'. also do check the small braided 'leak off' pipes that run between the injectors, and to the return line, and the end blanking plug as ive known leaks in these cause starting problems.

For 12 read 10 Laurence as yours is a five cylinder not a six!
 
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laurence

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c202 250td
  • Thread Starter
  • Thread starter
  • #6
number of seals

Hi, thanks for the info,will confirm that over next week.As I said, the seal at the top left of the filter was flat and changed that with others yesterday.Just went out to start the car,it fired up first time,so maybe it's cured the problem?Time will tell anyway and parked the uphill last night so as to provide a better test.So far changed 6,will do 2 more I can see the weekend,I hope!Thanks all,seems this is a common fault on these cars,at this age.
 

turbopete

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For 12 read 10 Laurence as yours is a five cylinder not a six!

there will still be 12 as they dont go anywhere near the cylinders. they go from fuel heater to pre filter (2 on prefilter) from filter housing to and from cut off valve, injector pump feed, return lines, its the injector pump thats different in the general set up, not the routing of fuel lines.
 

turbopete

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2017 '17' Ford Mondeo 2.0TDCi ST Line X 180 (sorry)
TP, explain how the 'leak off' pipes cause starting problem please. I may be wrong but I was under the impression that they're just return lines for fuel not used by the injectors. I had a couple of them leak when I first got my car but never had any starting problems. Just curious. :)

had many fords with starting problems over the years and changed the leak off pipes and the blanking bungs and all has been well again. it seemed that it was more a fuel pressure issue than an air in fuel problem TBH as the leak off rail must affect the fuel pressure as they all run through from 1 injector tothe next. it seemed to take a couple of extra compressions to get going. nothing major, and only if the leak was bad. in my opinion, for what little they cost, they are worth changing anyhow if they are a few years old
 

roadhog

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They let air into the system which for a diesel is a nightmare scenario.

They're return lines, how can they let air in when the fuel is under pressure from the injectors? I've read somewhere on here that air in the fuel lines isn't too good, I think TP may have mentioned it. :D
 

turbopete

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They're return lines, how can they let air in when the fuel is under pressure from the injectors? I've read somewhere on here that air in the fuel lines isn't too good, I think TP may have mentioned it. :D

me? what would i know about having air in fuel? never heard of it before, and certainly never experienced it! :rolleyes::rolleyes::rolleyes::rolleyes:
 

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