Volumex woes

[Hamish]

Folks,
Some of you might recall a previous post about me being happy again - with a VX coupe staying with me for some fettling.
It has an unusual fault which I hope someone else will have seen and fixed - as I'm getting towards my wits end.
It goes like this :arrow:
The car starts beautifully from cold and will drive for all of a 1.5 miles before stopping dead. It stops because there's no petrol in the carb, but the fuel pump is still working.
The fuel pump has been replaced (just as well as the old one was knackered) and most of the under bonnet fuel line has also been replaced for something less dangerous than what was there before....
Tha carb has been cleaned inside and out. The Dizzy cap, rotor arm, coil, amplifier and plug leads have also all been changed - and although it's bit 'perkier' with the new bits the fault remains..... The pressure regulators are working fine and by-passing the mercury switch makes no difference whatsover.
Anyone got any suggestions of where to look next :?:

As an aside, there have been previous posts about VX exhausts and a mysterious bracket on the floorpan behind the flexi section of the exhaust. As this car is highly original I can confirm that there is indeed an exhaust mount there designed to support the exhaust just back from the flexi section - it comprises of a bracket going around the exhaust with an inverted 'u' to take a rubber.

Right now I'm off to knock my head against a brick wall for an hour - just in case it helps any :roll:

[Ken H]

Clogged fuel tank air vent? Try removing the tank cap to check for a vacuum. The tank would have to be nearly full (small air volume) to get only 1-1/2 miles.

Don't know the car, just a random suggestion.

- Ken

[chrisc]

could it be something like with the automatic choke it is getting enough fuel to run but once that is done with it goes?
Are you getting the correct pressure in the system?
Perhaps crud in the fuel tank is getting stirred up with the initial movement then blocking the filter then settling back down again?

[Grundo Farb]

Have a similar problem where the car starts fine then runs terribly after driving down the road, it seemed to be intermittent until it cut out completely on the way home last night. Its in the garage at the moment, hopefully will be able to determine what the problem is - it sounds similar as it feels as if its not getting the fuel into the engine and is particularly bad when accelerating.

Will post whatever I find out.

[cthargiss]

Had a similar problem with a US Beta Coupe. Traced (finally) to the fuel pickup clogged with rust from inside the tank. Cleaned and coated the tank, end of problem.
Craig

[Hamish]

Thanks for the ideas chaps :wink:

I had thought about a blocked fuel line/tank problem - but the fuel is still getting pumped through the system although it could be worth trying Chris Bastows (www.betacar.co.uk) suggestion which is to knock the filter off the inside of the tank and hope for the best..... but I'm not convinced as fuel is still being pumped at the required rate.

We tried a filter king system on the car after bypassing the mercury switch and the in line pressure valves; but the problem remained and there was fuel in the filter king bowl - therefore we know there's fuel getting that far.

This makes me think it must be an electrical fault somewhere - but where :?: I no longer have any VX wiring diagrams (hopefully Rossocorsa will come through on that one)..... but I have an inkling of an idea that it might be an ignition switch problem.
Its dry today ( :!: ) so will have a look through the ignition side of things and see if anythings up - after I've mowed the lawns :twisted:

Will try taking the fuel tank filler cap off and see if anything good happens, but with a half tank of fuel in the car I have my doubts :?

Did I say I was missing having a Beta :?: Doh :!: :!: :!:

BTW - Chris - how was Glastonbury :?: Turns out my wee sister was there as a bouncer :lol: :lol: :lol: :lol:

[cthargiss]

Hamish, You might try sucking fuel through the lines with a Mighty-Vac or similar. Anything over a couple of mmHg means that you have an obstruction in the fuel system. Since fuel pumps push much better than they pull, it doesn't take much to reduce flow enough that the car will idle but not run under load.
Craig

[Hamish]

Still can't get the car to run 'long term' (ie: more than 10 minutes stood still and revving.....). I went over the entire under bonnet fuel circuitry today with a multi-meter and I'm still none the wiser as to why it's misbehaving so badly -this problem is damn irritating now as everything else is done :roll: Hateful :evil: :evil:

I'm going to try a wee experiment with carbs next.... although the carb on the car has been cleaned I have several left over from the days of Mario and it won't do any harm ( :?: :!: ) to pop one on and see if the car will run for more than a few minutes/seconds.

After that I'll be tring the ignition switch/circuits..... then re-check the timing...... then I'm going to look for a nice big box of matches :twisted:

[chrisc]

Seeing as it seems to be temperature related and youve played with the fuel system to death id start looking at the other side of the engine bay. Are any of the wires nadgered or happily old wiring wrapped round a coolant hose to make sure it gets extra hot?

That and the carb of course.

Silly question - you have checked the temp sender in the head yeah?

[DJ]

... then I'm going to look for a nice big box of matches :twisted:

No!!! Don't do that. Just ship the whole thing over to me. :twisted:

[VX131R]

I'd be checking ignition. If it is heat related, which it sounds, look at your ignition module (assuming your car has the weber marelli electronic ignition, 4 pin ). Try to get the engine to fail from cold startup with a heat gun/hair dryer aimed straight onto the module. May need to remove from Heatsink. If the engine misfires, or stops you've proved your fault. This is not the best way to test, but easy to do and usually works.

[Hamish]

Chris - yep, checked the temperature senders and they are perfect, wiring is good too.

DJ - This ones not mine - I'd be tempted otherwise :wink: :twisted:

VX131R - The ignition module is brand new, I changed it at the very beginning of the cars 'stay' with me as I guessed it would most likely be the module failing...... but if I do give the hair dryer approach a try (and it works) I can't see why the carb should be dry of fuel....... or am I missing something :?:

I should never have sold on my VX manuals..... there's a lesson in there somewhere :!:

I have since been told by the owner that the car did start this problem intemittently just after he got it back..... and it has increasingly got worse.
If I don't find the problem soon I may have to accept defeat :arrow: this is quite unacceptable I've not been 'beaten' by a Lancia to date and have no intention of starting now 8O

[VX131R]

am guilty of not reading the whole thread... faulty ignition would definately not cause your carb problems,...unless and this is a very big IF, your car was similar to most efi settups and the fuel pump power was cut through its relay when igntion wasn't happening...like I said doubt it very much for a carburetted settup. the only other thing I could add is make sure your module is not a cheap aftermarket one, the current control on cheap modules is terrible under load.
Sorry can't help any further, don't know bugger all about carbs only EFI.

[andybeta]

start from the fuel tank and work toward the carb.

The fuel line enters the engine bay alongside the cam cover and then goes into a small cylinder round module, hot start I think which regulates fuel flow which is attached to the side of the power steering reservoir, then the line goes around the inside of the front behind the headlights and into the carb. This module can go faulty and stop flow. By pass it if flow is restricted and work methodically to the carb checking that you have lots of fuel passing along the line at each stage. if there are no restrictions fuel should flow out into your jar happily....

Or it could be the diapragm in the choke that has punctured but this would mean that the engine would rev at about 3,500rpm continuously.

hope this is of some help.

[Grundo Farb]

Do you know there is no fuel in the Carb?

If so then its a waste of time saying that my problem was traced to the connections in the distributor , they would short out after the engine got hot and when you put your foot down - the vacuum advance would come on and the distributor would short out - killing the engine.

It may be something to check - whether you have a spark after the engine dies.

[Hamish]

Yep - dizzy is next thing on my list of things to check, as I've experienced problems with them before. Although there isn't any fuel in the carb it is a possibility that the dizzy is responsible for the problem :roll:

I'm on holiday for a fortnight so we'll see how I get on - hopefully better than present :?

[Neil]

Any update Hamish? Did you get to check for a sticking float valve yet?
I know how annoying these faults can be, as I have several if anyone wants one! From bitter experience I learnt that just because you have checked/changed an item doesn't make it fault free! I just want to add a big 'hello' to all the other Lancia fans on this site. Took me a while to find it (thanks Hamish!).

[Hamish]

Neil :!:
Glad to see you've made it here at last :wink:
I had the carb apart today and found a couple of blown seals.
Replaced these from my 'stock' and checked the float/needle valve - seemed fine. :mrgreen:
....... fine that is until the same problem arose but thistime the car doesn't cut out due to fuel loss. What the problem has 'manifested' itself as is odd - damn odd :?

The problem does seem to be timing related - or something in the electrics as the car now 'hunts' over a huge rev range (nothing to 4,500 rpm) which makes me think there's something far wrong somewhere in the timing although it drives well when cold.......
Heating the amplifier made no difference, although the new coil gets warmer than I'd like.

I'm off for a weekends fishing - hopefully will be fresh in time for a new effort on the car in the coming week as I'm on holiday (again 8) ).

[Hamish]

Did I say I was missing Lancias :?: I LIED :evil:

[chrisc]

Sticking float needle valve? beginning to become stumped.

[Tom McGaffigan]

The stock Volumex has all kinds of supercharger venting hoses pump, fuel hoses, thermostaic vacuum lines, fuel return etc. After 20 years I wonder if all that is still working correctly. When I installed my Volumex I got rid of all that mess, plugged the vents on the supercharger and just have a single fuel line to the carb. I would do the same on your VX. In addition, I would add an in line fuel pressure gauge to insure that you are getting full fuel pressure. I run 4 PSI with my DCOE setup, the stock carb should run about the same. With no fuel in the bowl either the fuel pump is being shut off, malfunctioning oil pressure switch that shuts off the fuel pump perhaps, or the fuel pump itself has a problem. Check the grounds on the fuel pump also. I had a similar problem with the stock electric pump on my car and it turned out to be the shaft in the electric fuel pump being worn on the flat that engages the magnetically coupled fuel pump rotor. There was a worn spot on the flat that caused the rotor to jam when the pump warmed up. Filing the flat, flat again, eliminated the problem.
Tom McGaffigan

[Fingers]

Maybe I've got it, but if you've been over everything with a multi meter then maybe not. I had the exact problem on my way home from work this evening, ran for ten mins, not even then stopped, would almost kick into life, then stop, idle for 5 seconds then stop. My problem was that on one of the water lines into the choke, (top line) there is what I assume is a temp switch/sensor, not sure which, anyway one of the electrical connectors had come off. Now maybe your switch has given up the ghost, hope this is of assistance.

[Hamish]

A quick update on the VX - no news. I have the VX manual at home now so will see if it sheds any light on the subject......

Will start by re-setting the timing etc etc and starting all over again :evil: from the beginning - oh deep joy. Be still my beating heart :roll:

[Will]

Hamish, there's a funny little device at the bottom of the carb that is a temperature controlled valve- it's the one that is designed to bleed off vacuum that controls the vacuum-actuated valve in the coolant line that runs to the intake manifold heating circuit.
Try taking the tiny rubber "air filter" off of this fitting, and put a vacuum cap on the "T" fitting about a foot upstream in the line, and see if it solves your problem.

I can see the possibility of this inducing a vacuum leak, only when the car is hot, that would lead to a fuel delivery problem if all else was in order on the carb.

Also:
It did not escape my observation, that if I read correctly the problem manifested itself after you changed the ignition module? Is it one of the GM modules? Did you use the heat sink grease when you mounted it? If not, I would toss it, and spend $20 on a new one, and lube it to the heat sink properly, just to eliminate it as a potential problem.

Just more for you to chase ;) Remember: Beer is your friend !
-Will

[Hamish]

Cheers Will :wink: I hadn't considered that little fella.... will have a look when I get home after nightshift - or when I wake up :mrgreen:

Sadly the fault was there before the new coil went on - I made damn sure I followed all instructions with the grease/fitting.

If I'm honest, I haven't touched it for a week now :oops: and am summoning up the energy for a (hopefully :!: ) final effort.

[Hamish]

Folks,
Another quick update.....
Decided a fresh perspective was needed so Mark (who runs my local garage) and I have spent the better part of three days trying to resolve the problem - with a woeful lack of results :oops:
The carb (and all my spare VX carbs have been stripped, rebuilt to the correct specs and tried on the car - no joy.
The timing is spot on and the dizzy is working fine (it's been off the car, stripped and checked). The vacuum advance is also A1.
The upshot is the tough decision has been made to 'trial run' a whole new electrical supply to the fuel pump (to include an inertia switch) and to by-pass the mercury switch completely..... the mercury switch has been getting hotter than I would like but by-passing it hasn't made a difference (so far).
If the trial run works, we'll be completely re-wiring that part of the loom :cry:
Can't say I'm looking forward to this job, but it's high time the VX was returned to its owner so drastic measures are required to get a 'result'. Going to do one or two other bits for its MOT, so will be with me for a bit longer......
Despite all the hassles, I do still hanker for another Beta..... if only I could convince 'she who must be obeyed' that it would be good for my sanity :D

[andybeta]

Fuel pressure regulator could be duff and restricting flow?

andy

[Hamish]

Folks,
Another update on the sick VX that seems to have moved in with me :roll: Mark at my local garage has done a grand job so far - but he works single handed and time isn't on his side for a 'non priority job' like the VX so I've been 'meddling' again.... :wink:

I stripped down the carb (again - I could do it in my sleep now :x ) and it was fine. I 'jury' rigged a temporary fuel pump circuit in the hope that might be the problem. It wasn't :?

So I then re-checked the fuel delivery.... guess what :?: It's down to a trickle again :evil: :x :cry:

This can only mean one thing :arrow: there was substantial evidence of 'resined' up fuel lines with the car being sat for so long with fuel in it.
I'm now convinced the problem is tank related (despite so much evidence earlier on of other problems) - i.e: it's stuffed with crap which is intermittently blocking the fuel flow to the pump and therefore the carb which would explain the whole problem.
Sounds good :?:
Yes, possibly too good to be true it's so simple - it's also something I've considered before, but cleaning out the tank means taking it out of the car which is possibly one of the most hateful jobs on a Beta :roll:

At least I'm sure we're now 99% of the way to sorting this out once and for all, but I'm toying with the idea of by-passing the mercury switch completely and going with a filter king pressure regulator. This is due in part to the fact I want to see a in line filter 'in the system' but also due to the fact I don't trust the mercury switch or the standard pressure regulators :!:
It's not my car - if only it were - but I think the owner will agree to it as an alternative to the original system.

Comments :?:

[cthargiss]

Hamish, You might be able to avoid dropping the tank. The pickup is accessable from inside the boot. Clean or replace the pickup screen, blow the fuel lines out with compressed air, pour a pint of HEET or other fuel dryer into the tank, aggitate, and suck clean with a syphon pump. If there is no rust in the tank, you should be good to go. If you find flaky rust, then you will have to drop the tank to have it cleaned and coated.
Craig

[Hamish]

Good thinking that man :!:
The only thing that worries me is apparantly the VX and IE tanks gave a different 'pick up' or filter and/or baffle inside the tank (I dunno - never disected a tank for a look see). It's been suggested I find a suitable 'drift' and smack it until it falls off inside the tank - problem solved :?: :?:
I'm going to try and find some time for it on my days off, but time is what I seem to have woefully little of at present..... :roll:

[Fingers]

Have you had a good look at all the components in the hot starting circuit next to the blower, I've had a similar trouble to you and am thinking about getting rid of the whole lot. There's a relay that acts on an electrovalve that limits the fuel flow when the under bonnet temp is high, it drops the oriface the fuel flows through from 3 to 1.5 mm.

[Maigret]

I assume the fuel shut off valve has been checked?

Anyway the talk of cleaning out the tank reminded me of a funny story.

A carpenter at work had recently got a new car. His kid has put some stones in the petrol tank (they do helpful things like that don't they?). He drained the fuel from the tank and got a few stones out of the drain plug hole. There were some too big however.

Brainwave. Use the wifes vacuum cleaner to suck the stones out. This worked fine up until the point where there was an almighty explosion. While recovering from the concussion of the bang the wife runs out to find him holding the nozzle and a short shredded bit of hose. Her cleaner in thousands of pieces all over the drive.

[Hamish]

Yup - all been checked :cry:

I've been too busy of late to have a crack at it but may have a go tomorrow (after night shift you see :wink: ).

The joys :evil:

[Maigret]

I'm just about to go to work. Night shift.

[Hamish]

Yup.... night shifts - they suck :evil: :x

[Hamish]

So a new year and new ideas on how to get the VX that's been 'with' me for the last 6 months running right......... and guess what :?:
Yep, cracked it 8) :D :mrgreen:
Running like a dream - fingers crossed :D In the end the problems were fuel related and the cumulative answers of many weekends and days off were the following (not in any order of importance):
Fuel lines full of 'varnished' old fuel.
Knackered fuel pump.
Knackered fuel lines.
In tank filter - on VX and IE cars - full of crap. Drilled it full of new holes and fitted a big in-line filter in an effort to ensure this doesn't cause a problem again :evil:
Electrical problem with wiring to pump - cut out a small section, put in new cable and bingo - no worries.
Changed the ignition module again :arrow: actually, put an old spare in..... Took the car for a spin and after 5 miles it started mis-behaving :( changed the module and it ran prefectly again. Weird.
Carb - ended up taking it apart for the tenth time and getting the components 'sonic' blasted at a medical facility. Cleaned it all again, rebuilt it and runs a treat :)

So only a few things to do for an MOT and it'll be gone from my care - I won't be too upset 8) :lol: :lol:

[SubGothius]

Changed the ignition module again :arrow: actually, put an old spare in..... Took the car for a spin and after 5 miles it started mis-behaving :( changed the module and it ran prefectly again. Weird.FWIW, this sounds to me like (whoa, deja vu... :?: ...but besides that) the connection to the ign module is a bit dodgy; i.e., when you swap modules, that jostles the wires/terminals just enough (or scrapes a bit of oxidation off the terminal faces, prolly on the side the module plugs into rather than on the mods themselves) to pass current consistently, but then vibrations from driving it a bit may degrade the connection (moreso than cursing at it while troubleshooting would have degraded it to begin with! :lol: ).

[Will]

....that's a good point- in my car, I got an intermittant connection at the ignition module plug, and my first thought was that it was the pickup wire inside of the dizzy, which is known to go bad on the Plexes so often as to be "notorious".
But, it turned out to be the other (module plug) end, in which the little wire had broken right where the plug body attaches. I cut the plug off and used two different sizes of Jackson crimp terminals to get by, solved the problem. I have since bought a new $35 Marelli pickup but am now waiting for my repair to go south before I replace it because I am a mean stingy bugger.
:)

Glad you finally sorted it!
-Will

[chrisc]

Now the owner will just have to deal with the rust it will have accumulated whilst its been sitting :)

[Hamish]

Rust :?: Young Christoper - go stand in the corner of the room with your head bowed low. It's been in dry storage all this time 8)