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mangobob · Feb 2nd, 2020, 17:57

After a bit of digging,I’ve found the reason for my cold start problem.
On top of the fuel filter there is a non return valve.This is held in place with a plate using two 7mm bolts.The garage it last went into worked on my car and this plate had been taken off and put back on the wrong way round.I’m guessing they took the valve off for some reason?.Problem was they failed to re-seat the valve on the O-ring.This was allowing air into the fuel system causing poor running/power loss.The non return valve also turned out to be faulty as on testing you could blow through the valve on the non return side.This was allowing fuel to drain back to the tank over night and leaving air in the filter.
Perished fuel lines replaced and new valve/filter fitted and it’s sorted.
One bit of advice,when fitting the new valve you may need to use the old O-ring(mine was in good shape)
Carefully remove the O-ring from the old valve and fit to the filter housing and then gently squeeze on your new valve using some diesel for lubrication.
Make sure it’s seated down the refit the plate.This only goes on one way.
Hope this is of some help.
If you having issues with starting check your non-return valve.

Feb 2nd, 2020, 17:57	#9
mangobob New Member Last Online: Mar 17th, 2024 16:20 Join Date: Jan 2008 Location: whaley bridge Derbyshire	D5252T Cold Start Problem After a bit of digging,I’ve found the reason for my cold start problem. On top of the fuel filter there is a non return valve.This is held in place with a plate using two 7mm bolts.The garage it last went into worked on my car and this plate had been taken off and put back on the wrong way round.I’m guessing they took the valve off for some reason?.Problem was they failed to re-seat the valve on the O-ring.This was allowing air into the fuel system causing poor running/power loss.The non return valve also turned out to be faulty as on testing you could blow through the valve on the non return side.This was allowing fuel to drain back to the tank over night and leaving air in the filter. Perished fuel lines replaced and new valve/filter fitted and it’s sorted. One bit of advice,when fitting the new valve you may need to use the old O-ring(mine was in good shape) Carefully remove the O-ring from the old valve and fit to the filter housing and then gently squeeze on your new valve using some diesel for lubrication. Make sure it’s seated down the refit the plate.This only goes on one way. Hope this is of some help. If you having issues with starting check your non-return valve.