VWDiesel.net The IDI, TDI, and mTDI source.

General Information => Troubleshooting => Topic started by: mike_6kv on August 22, 2008, 11:35:42 am

Title: fueling i think?
Post by: mike_6kv on August 22, 2008, 11:35:42 am
hey

ive been browsing the forum for a while, i find it very helpful
ive just joined up and im looking for some help

i finished building my 1.6td bout two weeks ago before this the engine hadnt ran for over a year the spec was

gasser inlet manifold
gt15 turbo
1.9 head gasket
aaz fuel pump
fmic
and boost

i had trouble starting it from cold every morning
my thoughts were the gasket because of the lower compression

i thought i was also having problems with the 1.9 pump overfueling because of the smoke, i turned the fuel down numerous times but still smoke there was no responce in the pedal till about half way

so i changed the head gasket back to standard and i have gone back to my 1.6 pump which has been sitting in the shed for around a month

today i finished re timing the engine got it all spot on but it seems there is hardly any fuel getting to the injectors

could the pump vanes have seized?
its got to be fueling
any help guys

cheers
mike
Title: fueling i think?
Post by: BlackTieTD on August 22, 2008, 12:20:58 pm
a quick check would be to see if the fuel is flowing at a normal rate. do you have a clear fuel line going to the inlet on the fuel pump? its useful to have a clear line there to monitor bubbles and fuel flow. if the fuel isnt flowing out the injectors its also likely not flowing very quickly through that tube. it has to go somewhere..

oh and welcome  :mrgreen:
Title: fueling i think?
Post by: burnt_servo on August 22, 2008, 12:52:56 pm
if you don't already have one , get a lift pump and put 10 - 15 pounds of fuel pressure into the injection pump .

other things to look for , in the fuel tank , the pick tube is suposed to have a screen on it that plugs up . ( i carefully removed mine with some well applied air pressure  ...... don't try this at home ) .

also fuel filters are cheap , if it hasn't been replaced recently , now might be a good time .
 
there is also a good chance you have air in the system that will take it's time to work it's way out ( this is where a lift pump is priceless , as it will burp out air very quickly ) .

also if the engine has sat for any length of time , the injectors might be sticky or stuck  ( thus the black smoke )  .  a couple litres of atf  in a tank of fuel and a long , longgg  drive can fix that .
Title: fueling i think?
Post by: jimfoo on August 22, 2008, 02:08:19 pm
Do you have a boost gauge, so you can see what your turbo is doing? Does the 1.6 pump have an LDA, and have you adjusted it at all. No LDA would give much lower power. The AAZ pump with a 1.6 pin and AAZ spring could cause excessive smoke. 1.9 gasket wouldn't matter much as long as it was the same thickness. Maybe the AAZ pump was 180* out?
Title: fueling i think?
Post by: mike_6kv on August 23, 2008, 01:43:59 am
cheers for the repiles

i had the car running for a week then it was refusing to start at all, so i was using cold start spray, now since changing gasket and pump seems the pumping pressure is too low to the injectors

i have the clear lines and can see fuel in them

i also have a boost guage and the 1.6 pump has the lda,

could the pump be air locked?
Title: fueling i think?
Post by: jimfoo on August 23, 2008, 06:46:42 am
Is there any signs of leakage around the input shaft? Maybe the pump could be sucking air from there, which wouldn't be visible. Try to plumb in a low pressure electric lift pump and see if that makes any difference. BTW, if your cold start spray is regular starting fluid for gassers, DON'T USE IT! It is very bad for diesels. Are you positive the glowplugs are getting power and actually glowing red? If you have low compression(should probably check), you might not be able to start it without all the glowplugs working.
Title: fueling i think?
Post by: mike_6kv on August 23, 2008, 09:40:39 am
thanks for the help

so today i swapped back to the aaz pump, and same thing happened, very little fuel to injectors.

i began kranking it and used the cold start spray again just one squirt, it started but cut out.
abit pissed off i decided to constantly spray it in to the intake for around 10 secs and it began to run very rough, i turned the fuel up a touch after a few mins it started running steady but with white smoke, took it round the block came back the smoke had stopped and was running sweet and quiet to.

my thoughts were that the pupmed was airlocked and the starter motor didnt have enough power to overcome it, but the start spray got it running fast enough to overcome it.

any one ever found this out?

jimfoo- the spray says it can be used on diesel but NOT using glow plugs
but is it still bad?

thanks for the help guys much appreciated
Title: fueling i think?
Post by: gigaz2 on August 23, 2008, 11:04:22 am
starting fluid on a diesel is always bad news, but necessary sometimes.

make sure your battery is fully charged, no losses in the cables, a good starter.
you can't start a perfectly running engine with low cranking speed, let alone one that has issues.
Title: fueling i think?
Post by: mike_6kv on August 23, 2008, 11:58:18 am
cheers

well it seems my glow plugs aint workin properly, as it took a while to start before so thats next on the list.

im just glad its running really well when it does start lol

again thanks for all the help
Title: fueling i think?
Post by: mike_6kv on August 24, 2008, 04:40:34 am
the glow plugs seem to be working but it still wont start

what could be the result of low compression?
Title: fueling i think?
Post by: BlackTieTD on August 24, 2008, 10:18:03 am
did you change the fuel filter? if you think its before the injection pump (fuel blockage or whatever) just pull the intake fuel line off the fuel filter and run the injection pump directly from a little cup of fuel. free check..
Title: fueling i think?
Post by: BlackTieTD on August 24, 2008, 10:18:54 am
ps - low compression certainly will cause the engine to not start, or run poorly when it does start. diesels rely primarily on pressure to ignite the fuel.
Title: fueling i think?
Post by: mike_6kv on August 25, 2008, 07:01:38 am
thanks

ive found the problem,
i decided to check the glow plugs again, took them out and heated them

not one of them heated

4 new plugs later runs like a dream

cheers guys