fuel pump ( done more tests)
Turbo Mini Forums

ive just took my feed in to my fpr off to test what comes out and its not pumpin any fuel out reletivly quickly, iv e gauged it with an old oil press gauge and it gets up to 90 psi and really slows the pump down so pressures not a prob but the flow seems piss poor for such a powerful pump, quick answeer please

Edited by miniman on 6th May, 2005.

Supply to the pump is restricrted?

just goin to check now, prob is that have half a tank of fuel. lol.

supply to the pump is wicked, flows like sh*t, i have a 12m inlet on the pump so dont think that should be a prob, lines are free, is the pump fooked? lots of rusty residue in filter

i would go for the pump if....................................

it can only be the pump or the lines or the reg one of the three

if lines ARE clear like you say.... then the pump looks the likley culprit especialy if its off the original metro

would be some 15 years now and worn

the fuel flow should be around 3 or 4 inch of steady stream into a container free flow through say a 8mm bore as a guide

the pump output is approxs:- 1.5 litres per minuite

below this its fooked !!!

so get the stop watch out and the coke bottle ....

Edited by BENROSS on 4th May, 2005.

it filled a big nescafe jar(must be 3/4 of a litre at least) in 36 seconds so it cant be that bad, im in a pickle, the pumps only 3 months old, so's every thing. could my prob jus be the ignition module or is the pump faulty sometimes??????????/ peice of hair gone.l.........

supply to the pump is wicked, flows like sh*t

Is this as in the supply is good, or not good?

Read the facts - Youve WITNESSED a fuel pressure anomoly at the same time as the engine problem (your other post). Concentrate on this area - re-test if neccesary - before looking elsewhere.

By virtue of your filter being full of something unpleasant, this is also pointing towards a fuelling issue?

but dont understand, fuel pressure pump side is good, flow appears to be ok, reg sets and rises with boost, pipes to and fro are good, clear and correct size, if theres shit in the filter after the pump that must of gone through the pump then, could this be it? shit stopping fuel supply every now and again when asked to draw excessivley, or the reg doin the same, either way i should nt of got 0 psi on the lo gauge should i no matter what,

right then listen to what dave says

use your head and work through methodically

strip the fuel reg and look for signes of debris or a pin hole in the diaphram by GENTLEY pulling at it examine closley .......

then make sure the fuel lines are CLEAR by using compressed air feed and return to tank

and after that check that the breathers clear on the tank...........

dont panic and go through it right

ok, done a few more tests tonight, i stripped my fpr and found nothing wrong in there, i tested the lines again properly with my compressor and the return seems to be restricted when the caps on, when you take it off its fine, i put it back together hastly thinking this was the problem, went for a run with cap off and its still the same, dying on boost, strange thing is it misfires and back fires, would it back fire if it ran out of fuel??? also if i hold it at a certain rev ie when cruising the engine note is more of a misfire than steady rev, but it dont hold back or anything, i also get a fuel pulsating same as neil on my lo gauge. clues, clues, clues. its booked for show n shine at drayton manor custom car show this sun and i really really want to go, ive got a new fuel pump to try tommorow any way, only £50 new, i was robbed with the other one.

Return will be restricted in your test, as you weren't taking out what you were putting in (if that makes sense!). Taking the cap off confims it is ok.
What size are your supply / return lines? Are you running a restrictor at the inlet to the regulator (needed if running same bore supply and return pipes).

All seems ok thus far then, bar the fuel pump - which you will isolate shortly...
I'm still confused as to your comments about the 'lack of flow' and 'drop in pressure' previously however...


I believe Wil suggested it could be the module - well given what you said, I was thinking it probably was fuel related - but you seem sure that everything is ok now, so lets look at the electrics - if anything, you can isolate these so you are 100% sure it IS or ISN'T a fuelling problem:

The following is something I've typed out many times - but can never find it! So, I've now got it saved as a word document that i can copy and paste! LOL!

1) Find a small bulb (like the size as fitted to the instrument binnacle / gauges) .
2) Connect two long lengths of wire from the positive and negative terminals on the coil.
3) Run these into your car through the bulkhead or door .
4) Connect them to the bulb. You might want to add a simple switch – your choice.
5) Fire up the engine. At tick-over, you’ll see it clearly flickering very quickly. As you blip the throttle, it’ll appear to glow brighter. All it’s doing is flashing faster, hence appearing brighter. Over 2000rpm, it won’t appear to get much brighter at all.
6) Go for a drive – the same way as previously generated the problem. The bulb will of course be shining brightly. If it flickers as the engine misses, you have a module or ignition-live supply (or possible a coil) problem.
7) If it doesn’t flicker, your ign-live and module are almost certainly ok. Your coil might still be suspect however. Easy trick here, is to tape a strobe lamp to your bonnet, fitted to one of the plug leads. I favour using one of those really cheap strobe lamps that are next to useless for anything other than tests like this!
8 ) Again, you’re looking for a marked reduction in the number of ‘pulses’. Clearly, if the revs drop because of a fuelling problem, it will appear to flash less. At 80+mph in 4th though, your revs won’t drop that quickly!

One final (but important) question – you do have +12v to your coil don’t you – ie NOT the pink/white wire…

Edited by turbodave16v on 5th May, 2005.

edit; im running 8mm too and from with no restrictor is this prob?

thanks, great info, yes im runnin 12v straight off the ign barrel, it seem to get worst when i fitted a set of plugs last week, i was runnin standard plugs not knowin, i was explainin my prob to ian at avon bar and he asked what plugs i was runnin, he said standards ll start to glow at the end and i need inverted ones, i thought this would sort my prob for defo as i thought i might of been gettin pre ign with the other plugs, but it got worst since, i cant boot it for more than 10 seconds with out it doin it, but only does it when its hot, so this could be coil or module i suppose, a dodgy fuel circuit shud do it all the time??

Edited by miniman on 5th May, 2005.

Once you've cooked a module, it'll be fine majority of the time, and then only work intermittently - usually under load/accelleration.

WTF is all that about standard plugs glowing at the ends? I've never heard anything like that in my life! Your problem is occuring at low (<10psi)boost right? Hence standard metro turbo plugs will be more than up to the job.

Are you running the correct coil for the electronic ignition module? The Lucas Gold or other 'pretty' coils don't have a winding compatible with the modules - they do kinda work - but not very well...
Do the test above, and if any sign of probs, buy a new module.
When (if) fitting it, remove the old one, wipe the dizzy body clean, use a wire brush, brillo pad, steel wool, whatever, to clean the dizzy body. Apply nthe heat-conductive jelly to the new module, and fasten to the dizzy body. Finally, wipe off the excess.

Edited by turbodave16v on 5th May, 2005.

thanks chap, the spark plug thing was a freinds explanation to why i needed inverted plugs, i dont know these things im new to turbos, will that restrictor be a problem???, ill by a new module tommorow just in case i find in test that is faulty, i remember i had only the pink/ white wire runnin to the coil untill a couple of months ago then converted it to 12v, could i have damaged the coil initially.???

Unlikely to have damaged the coil - but it 'could' be goosed anyway (anythings possible). Might want to call and check if they have a coil suitable for electronic ignition aswell - gives them a chance to order one in just-in-case...

Doing the test above will show you the way - no point throwing money at a fault unless you know what it is first...

thanks for all info mate, will update tommorow night after tests, off to land of nod now

hang on a mo sounds like the problem i had with mine.
turn on ing, remove the fuel overflow pipe from carb, fit low gauge with a t piece into the flow to the carb from the prv. then wind up the prv until you get 10psi and see if any fuel comes out of the overflow if it does then your needle valve needs changing.

the miss fire when you come onto boost could be excessive fuel going into then engine this was my problem, but it done when it was on boostfor more than say 6-8 secs.

yours could be the same, just check it before you buy shed loads of bits, unlike me.

always looking for them bigger bunches of bannanas

That is very true!

I have not done that test but I thought that I had wrecked my mixture screw so decided to take off my carb. Thought I might aswell clean and overhaul it at the same time.

When I took off the carb there was a shed load of backed up fuel in the plenum chamber and the float level was out of spec.

I have to go house hunting tomorrow so wont be able to let you know the most recent developements until I have fitted the carb on sunday.

Got a good feeling about it, loads of crap in the carb any way so was worth the cost of the rebuild kit to just force me to take it apart for a clean!

ok tried ignition test and it was fine, never dimmed or missed a beat at all during problem, it could be what you say but i have a air/fuel ratio gauge and that goes to lean and then right off the gauge surely if its over fueling it would go to rich??? i just removed my dash pot and its coated with black soot nearest the plenum side, what could this be from???? it looks like when an exhaust has been blowing near something.

those gauges might not register quick enough.

i even pulled a plug out and it was grey , just give it a try before moving else were to find your problem

always looking for them bigger bunches of bannanas

miniman

Just digressing slightly but ….. what compression are you running ?

ie standard head? & do you have a intercooler fitted ?

Well ignition is isolated then. That is some good news.

Hoggy is right about the lambda gauge - they can be 250ms behind what is actually happening... Only a decent wideband gives fast readings.

That black soot is from a mis/back fire - as you've commented on previously.

Next things to try:
1) 4/5mm restrictor at the inlet to the fuel regulator.
2) Clamp the part-throttle lean-off hose on the carb (the one that goes from the front to the side).
3) confirm The regulator IS plumbed in right (some have arrows on the underside showing inlets and outlets - it WlLL work (poorly) if the fuel in and fuel out (to carb) are reversed - I found this out a long time ago!!!
4) Investigate the carburettor (below)



Remove the carb off the car (leave it on the manifold - much easier). Remove the dashpot complete Confirm the needle is secure.
Remove the bottom cover off the carb. check that the jet and jet holder is secure (there are two 'ears' on the jet that locate around the jet-holder plate - check these aren't broken).
Check the jet holder screw is tight, and the spring between the screw head and jet holder is in place.
If all looks good, remove the jet holder, and withdraw the jet. Check it isn't blocked.

Now remove the spindle that holds the float in place (you may have to remove an alloy cap over the allen-key head on the spindle screw). Remove the float, check there is no fluid in it.
Remove the needle from the needle valve assembly. Now remove the neele valve body (9/16 ot 1/2" AF socket I recall). Check the filter (if fitted) fitted above the threads on the valve body isn't blocked.

I've got a feeling you'll have found the problem by this point... It's all pointing towards a fuellign problem, and everythign else has checked out.

excellent, thanks for help you guys, dont know what id do with out this site, ill try hoggys test 2moz, then ill strip the carb and see what i can find, will i need a rebuild kit or will i be alright?, think ill put new pump on with new filter just in case, hopefully ill have good news 2moz.

ben ross, im runnin morspeed booster head and 15cc pistons 0n 1293 block, think we worked it out to be somewhere around 7.4 to 1, annoying thing is the boost im runnin now (7psi) is runnin in boost, hopefully the engine will have 15 to 20 runnin through it all the time soon, dare nt tweak it up with this prob or it ll be piston porridge, lol, big inter cooler too. will get some pics up soon, miniworld have just been out to shoot it for the front cover of august issue, i nearly killed the guy who came out rob hawkins, i was nailing it past a 206 gti who decided he wanted to race coming up too a blind bend, then the problem kicked in, lol.

dont buy any thing yet, just try what myself and turbo dave sugested first, as it wont cost any thing to try,

if it is the needle valve you can get these from minispares i have orded 1 but they havent got any yet.

always looking for them bigger bunches of bannanas

ok, to start with today i decided to rip the tank out and clean and flush it because of the dirty coloured fuel i was gettin, i got shit loads of rust particals out of the tank, i renewed the fuel filter too, i decide d to cut the fuel filter open and it was brimmed with shit inside, i filled it up with fresh fuel, i took it for a run and it never did it, i was nailin it quite hard for about 30 mins, it would of done it after a minute before, it did do it a couple of times at about 95 mph when i was full throttle for a long time, i think i found the problem, think the carb must just have a bit of shit in it now and again causing a hicup, its 300 times better though now, thanks for all your help, not gonna check the carb yet, gonna get a rebuil kit then do it properly, my luck ll say something will go wrong, thanks again.

jamie