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tears and blood won't get fuel to flow

BB d

BB d

Enthusiast
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87
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Nr Lewes
Ach.. I'm having the ranting, anger, frustration day..
my f4 1108cc (88) was driving beautifully. 3 days to be sure before I cancelled insurance on the prior car. and then the very next day. drove wonderfully for 5 minutes then no more.
The engine will start, and just about tick over but as soon as touching accelerator or chhoke - dies.
Local mechanic believed it to be the fuel pump - ordered new- waited - fitted
No difference - exactly the same.
so, stranded on a farm once again - Bugger!
any suggestions about what to try next?
weeping bb
 
Blocked main jet will cause the engine to cut when you use the throttle. It should work with choke but not without if the main jet is blocked. (Assuming choke jet is not also blocked).

If you take off the top of the carburettor you'll see the jet at the bottom towards the cabin. There is a brass screw in the bottom of the float chamber you can unscrew which gives access for a screwdriver to remove the jet. Poke something through, make sure there is a hole, give the float chamber a good clean and put everything back together.
 
malcolm said:
Blocked main jet will cause the engine to cut when you use the throttle. It should work with choke but not without if the main jet is blocked. (Assuming choke jet is not also blocked).

If you take off the top of the carburettor you'll see the jet at the bottom towards the cabin. There is a brass screw in the bottom of the float chamber you can unscrew which gives access for a screwdriver to remove the jet. Poke something through, make sure there is a hole, give the float chamber a good clean and put everything back together.
Click to expand...
Thanks, Malcolm
stalls with both choke and accelerator. a little choke and it goes for a short time. accelerator is like a kill switch
 
after viewing the fuel filter -
I'm thinking the key is no steady flow of fuel. (Thanks, Chris Ebeyer).
seems to dribble, disappear, splosh and bubble.. repeat

I tried blowing down the fuel pipe to diagnose if blockage, no joy there - was like blowing against a seal. (sore cheeks of bygone birthday balloon times) -

Reading what I can, I wonder if the fuel sender, or fuel gauze? maybe next..

wondering if I should still investigate the jet(s)?

hmm.. struggling to remind myself how much I've loved driving this car. Ironically I have a great Kia Picanto, an 87 super 5 GTS(running project for someone? tis not far from an MOT), both working, but it's the 4 that is insured taxed and mot'd.
ahhhh - anybody interested in the kia or the 5 - looks like I might need some funds for the 4
 
I would say blocked main jet for it to die with any throttle. I don't recall where the choke jet is but have half a feeling the feed is beside the main jet so if it's got scummy in there that might also be blocked.
 
malcolm said:
I would say blocked main jet for it to die with any throttle. I don't recall where the choke jet is but have half a feeling the feed is beside the main jet so if it's got scummy in there that might also be blocked.
Click to expand...
ok will give it a go. thank you
 
These are such simple cars to work on I am absolutely in awe that the mechanics out there are still incapable of correct diagnosis fair enough there are a lot of new enthusiasts now now on this group who will have limited car knowledge
but people paying professionals surely have got to expect correct diagnosis not guesswork
yours angrily
Paul Cunningham
 
There is no choke jet on carburettors with flap chokes, like the Zenith 28IF, so one thing less to check.
I place my bet on a bloked main jet, too.
 
grazzi, grazzi (from East Sussex)
tomorrow I have a mechanical friend joining me for a couple of hours - our plan is to empty the (full) fuel tank, drop and clean it incl compressed air through the lines - now here is where it gets interesting - after I fed back to him all I've read, and you wonderful folks have shared - he suggested we don't replace the inner gauze filter but add another fuel filter (type that is clear and insides viewable) between the fuel line and the fuel pump, as well as between the pump and the carb... then also to clean the jet.
Has anyone tried this before?
Any thoughts warmly appreciated.
living alone, in the middle of nearly nowhere, COVID n all, here, in this forum I don't feel quite so isolated
thank you all
b
 
If you're in East Sussex you do realise that I am am only in West Sussex so I can't be far away if you get totally stuck
 
You do know that it will take at least all day to drop the fuel tank., and another day to put it back
For your peace of mind, remove the fuel line that runs from the fuel pump to carb then turn the engine over. If fuel comes out of the fuel pump then your problem is not the tank so leave it in place.

I agree with all the above- its surely a carb blockage problem. Cleaning your jet is a couple of hours work at the most.
Somewhere on this website, I have a full video detailing carb removal and cleaning. Let me know if you can't find it
 
mojobaby said:
You do know that it will take at least all day to drop the fuel tank., and another day to put it back
For your peace of mind, remove the fuel line that runs from the fuel pump to carb then turn the engine over. If fuel comes out of the fuel pump then your problem is not the tank so leave it in place.

I agree with all the above- its surely a carb blockage problem. Cleaning your jet is a couple of hours work at the most.
Somewhere on this website, I have a full video detailing carb removal and cleaning. Let me know if you can't find it
Click to expand...
uh Oh - I thought a couple of hours for two people - hmmmm
I searched for carb removal and cleaning but can't seem to find it - might you have a link
 
Observations

The fuel filter is noticeably more empty, almost completely empty then a week or so ago when it always had some in.

Disconnecting the pipe and turning over there was indeed fuel coming out - kinda in spurts. with fuel filter attached. it often didn't appear, than would, a few drops, some bubbles, too, but not constant or enough to fill filter as before??

There was a good cm or so of petrol in the carb bowl

However - Jet was nice and clean.

the gasket had a slight tear, which separated at the slightest touch, bugger - and my full set of r4 gaskets.. .. has no replacement.

more hmmmm..

will try and cut myself a replacement from a sheet of gasket paper.

so .. ..

apart from having to fashion a replacement gasket, the carb looks good.

Anything apart from the main jet?

Gut tells me that the tank really wants a look .. but my friend only has a couple, maybe 3 hours free tomorrow - not one or two days - I can get access to the car lift at the onsite garage if helps.

sigh .. ..clean jet.jpegbroken gasket.jpeg
 
1 cm of fuel in the float chamber is a bit strange. Normally they are full to near the top. Maybe it is that fuel is not getting in.

If you disconnect the fuel line from the carb a squirt squirt is normal when you turn over the engine. You can get bubbles and air for the first few turns but after that it should be fairly consistent.

Assuming a reasonable amount comes out after a while there is another filter. The brass union that the fuel pipe attaches to on the carb has a metal gauze filter inside.

If you don't get fuel out then maybe blocked fuel filter between pump and carb, a split pipe between pump and tank letting air in, a hose that has failed causing it to block.

For diagnostics do the easy stuff first. Remove pipes, do experiments, and see if the system. Behaves as you would expect. Tank out and back in is only a few hours but that's longer than the other options so better trying those first.
 
Also make sure your fuel hoses are good, and good for Ethanol (a % mix in petrol) use as well - some non-tolerant hoses can perish and crumble withing months internally and can cause part-blockages that can move around. Cohline makes suitable 100% ethanol-proof hoses. Accelerator pump rubber on the carb could also be perishing I guess.

Check the fuel flow again - point the hose that ends up at the carb into a bottle and crank until no air comes out. If inconsistent or tiny flow, then start tracking back! It will pulse. As above, unscrew the carb petrol-inlet brass hose-tail and hook out the gauze filter. I've had grey gunk form in carbs due to the ethanol and/or water I think.

All advice from the other members above sounds good; the simple things are usually what goes wrong.
 
PLEASE don't take this amiss, but is the fuel filter fitted the right way round? When you said the fuel wasn't coming through when the filter was fitted I just had this thought...... As you say, sometimes the blindingly obvious is.....just that!
 
You say you tried blowing down the fuel pipe but it was 'like blowing against a seal'. This doesn't sound right to me - perhaps this is where the problem lies. I've successfully used a tyre footpump as a handpump with one of the plastic adapters for inflatables fitted (but remove the filler cap first); if you use the pump gently, you should be able to clear the blockage (you'll hear bubbling in the tank). It's a fairly common problem with cars that aren't used much.
 
Of course you should blow the line before the fuel pump...otherwise you will be trying to blow through the non return valves of the pump.

Direction of the fuel filter has no effect in fuel flow, but if you fit it the wrong way round, you won't be able to see its "dirty" side.
 
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