synergie diesel hard work to start - bubbles fuel line

[Harlequin]

heya all - been a while (reliable diesel and all that lol)

but , my little bus is having a tough time starting - it coughs when turning over till it finally catches , after searching I tried the primer and it was empty , but when pumping it up prior to starting , it doesn't fully help.!


changed the fuel filter as an attempt to fix it but still the same , any ideas?

[Hell Razor5543]

I would say that you have a fuel leak somewhere, allowing air into the system and letting the fuel flow back into the tank. The fact the primer is empty is a good clue.

[BX]

Seeing as it has a primer and I have never seen a synergies HDI with the siemens system I assume you have either a 1.9 or 2.1. if its a 2.1 I cannot offer any advice. There are 2 things that affect the starting of a 1.9. the most likely is a failed glow plug. This gives the symptom I think you are describing. The other is diesel leaking back to the tank. This is a common problem on several vehicles with injection pumps. The solution is to fit a check valve in the suction line from the tank. Most diesel specialists have them in stock. They are fairly cheap usually less than 10euro. It is normal to be able to easily squeeze the priming bulb. It is under suction from the injection pump and not under pressure. If it is a fuel problem priming before attempting to start usually works. I would be inclined to check the glow plugs first.

[Harlequin]

sorry yes its a 1.9TD bosch pump diesel

which glowplugs would you suggest?

[Peter.N.]

You can quite easily check the glow plugs by measuring the voltage between any plug and earth, connect the meter and switch to glow plug position, you should have between 10 and 11 volts for about 15 seconds, if you have 12v all the plugs are o/c, between 11 and 12 volts one or more plugs has failed, no voltage at all the circuit has failed, quite likely the relay.

Peter

[Harlequin]

and not 1 of them would get warm/hot/anything above ambient!

[Peter.N.]

That must be a record! Is a wonder it started at all!

Peter

[Harlequin]

they are in the order they came out - left 2 were behind the pump

[citronut]

i have seen a pug 306 with all 4 glow plugs completely dead, turned out in the end to be the glow plug timer, on this car it were the electronic solid state version, and it was staying on continuously, so it burned all 4 plugs out that someone else had fitted a month before the owner bought it to me

[homeruk]

As a precaution I would be doing a compression test on your engine.

You appear to have oil on two of your plugs which could be a sign of a head gasket failure.

[citronut]

You appear to have oil on two of your plugs which could be a sign of a head gasket failure.

it looks to me as the oil has run down the threads, maybe as the plugs were removed, as the tips only look sooty from not working

[Harlequin]

sadly - now with the cold weather , its not having a good time - feels like it goes on 2 then 3 then finally all 4 - really wants happy today at all

[citronut]

have you fitted new glow plugs yet Simon

[Harlequin]

good morning Malcom! yes they are fitted

im leaning towards 1 or 2 might not be working as advertised or the pre heater isn't working nor the fuel boost - I believe on cold days a manual system allows more fuel through at start , a sort of choke?

[citronut]

you are aware you must not let the pole/post on the top of the glow plug rotate at all on tightening the 8mm nut???????,

if the post dose rotate this will destroy the glow plug,

i believe these engines will start with the cold start wax stat not functioning, but will just run a bit lumpy and smoky till warmed up