Need some help with a vacuum hose connection

[AJ_Spider]

Hi Peter,

Yes, that is the thermostat in the coolant photo.

I have checked the distributor and it is a normal one without a vacuum advance. So I think we are back to square one in regard to the unattached pipe. Can we definitely rule out the possibility of attaching to the carb in the photo from my first post?

On checking the fuel lines they all seem to be in a reasonably good condition but I take your point and I will check them further in due course.

Andrew

[SanRemo78]

One daft question from me - are you still running the mechanical fuel pump? If the car has been converted to an electric pump the original may not have been removed. Should the pipe turn out to be a vacuum pipe and a potential cause of poor running I'd suggest blocking it to see if that makes any difference to the engine. Finally, a lack of start with only the battery warning light but no starter noises might indicate either a weak battery (charge fully or replace) or a poor earth from the battery to the earth point on the battery tray and/or poor earth from that point to the engine?

Keep at it, you'll get there!

[AJ_Spider]

One daft question from me - are you still running the mechanical fuel pump? If the car has been converted to an electric pump the original may not have been removed. Should the pipe turn out to be a vacuum pipe and a potential cause of poor running I'd suggest blocking it to see if that makes any difference to the engine. Finally, a lack of start with only the battery warning light but no starter noises might indicate either a weak battery (charge fully or replace) or a poor earth from the battery to the earth point on the battery tray and/or poor earth from that point to the engine?

Keep at it, you'll get there!

I've checked and compared with the photo in my Haynes and it's the original mechanical fuel pump. Food for thought on blocking the vacuum pipe, if it is as such. Maybe I should give it a go, if it definitely doesn't go to the carb?

I did charge the battery a couple of weeks ago and although it started straight after, in the next few days it goes back to struggling to start as usual. Only when I use the engine start on my battery charger will the engine start up after a few goes (but obviously still the issue with it stalling after taking foot off accelerator pedal). So maybe there is a drain somewhere as well, but I've not been able to trace it yet? If there was an earth issue it was something I asked the pro mechanic to look at last year, and I don't re-call him having any concerns about this. But who knows? There seems to multiple issues going on, each one maybe affecting the next one along, so a bit despondent to be honest 

[peteracs]

Hi Andrew

You showed the mystery pipe coming from the inlet manifold, so plugging it will only be a positive thing, give it a go.

As to battery, if it holds charge initially after a charge and starts the car, then disconnect it and leave for a period (24 hours?) and then reconnect and see if it still starts the same way. You can also use a multimeter to measure the volts at each occasion. If it does not start the same way then you have a poor battery. You may also look at the date on the battery to give you an idea how old it is. If the battery still starts the car as originally when just charged up, then you should look for a current leak, removing fuses in turn can often help, though direct connection to alternator can also be an issue. You just have to be methodical and patient……. This can be frustrating, but worth it in the end.

Peter

[AJ_Spider]

Hi Andrew

You showed the mystery pipe coming from the inlet manifold, so plugging it will only be a positive thing, give it a go.

As to battery, if it holds charge initially after a charge and starts the car, then disconnect it and leave for a period (24 hours?) and then reconnect and see if it still starts the same way. You can also use a multimeter to measure the volts at each occasion. If it does not start the same way then you have a poor battery. You may also look at the date on the battery to give you an idea how old it is. If the battery still starts the car as originally when just charged up, then you should look for a current leak, removing fuses in turn can often help, though direct connection to alternator can also be an issue. You just have to be methodical and patient……. This can be frustrating, but worth it in the end.

Peter

Hi Peter,

Yes I will plug the vacuum pipe and see if there's an improvement!

The original battery was replaced with a Yuasa not long after I purchased the car (in May 2019), so in theory it should still be holding charge. I have noticed on testing with a multimeter recently that it has gone from 12.5 v after a charge to around 11.3 v weeks later, so something is definitely going on there as well. I have looked at removing fuses in turn in the past but not been able to locate a faulty one as yet. As you say it's a case of being methodical, so I'll give it another charge today and start from scratch with the plugged vacuum pipe and possible fuse issue see how it goes.

Thanks again for all your help with this and I'll report back soon.

Cheers,

Andrew

[JohnFol]

Does this shed some light on it??

http://www.fiatspider.com/f15/viewtopic.php?t=28033

[AJ_Spider]

I've put the air filter back on, charged the battery (it was about half charged on the battery charger scale before this) and plugged the pipe. This morning it started after a few ignition key turns, but unfortunately I'm still getting the stalling issue if I take my foot off the accelerator. After a few attempts when it does re-start after a few stalls it will then turn over but won't fire up, so no progress really. I can only conclude that the pipe was connected to something, as if it had been plugged in the past this would still be the case? Maybe if I keep the vacuum pipe plugged, the connection hole in the carb where I thought it should go in my first photo attachment should be plugged as well?

I'm going to check the battery with my multimeter next and report back.

[JohnFol]

If you have auto-choke, press accelerator to floor twice before starting so choke is fully engaged.
Start engine as best you can. Put your finger over any hole or pipe that you think is a vacuum and see if there is suction. If so, just block pipe (for now). Get some carb cleaner and squirt it around gaskets, manifold etc. For example I found an increase in revs when squirting near inlet manifold, meaning I had an air leak. Squirt it in air intake and if revs increase then look at fuel supply / mixture


BTW where in the country are you?

[AJ_Spider]

If you have auto-choke, press accelerator to floor twice before starting so choke is fully engaged.
Start engine as best you can. Put your finger over any hole or pipe that you think is a vacuum and see if there is suction. If so, just block pipe (for now). Get some carb cleaner and squirt it around gaskets, manifold etc. For example I found an increase in revs when squirting near inlet manifold, meaning I had an air leak. Squirt it in air intake and if revs increase then look at fuel supply / mixture


BTW where in the country are you?

Thanks, I'll give the auto-choke suggestion a go tomorrow.

I checked the battery with a multimeter and it was showing 12.45v consistently and also with lights turned on it was above 12v. To me this indicates that the battery is giving good charge or am I mistaken?

I'm also checking the distributor cap cable connections – I'm sure I labelled them correctly and marked the cap position the last time I took the cap off to check the condition of the distributor (which was like new), but just wondering if anyone has the sequence for cross checking, just in case I was an idiot when putting them back in?

John, I am over in Cardiff

[JohnFol]

12.3v to 12v is a good sign (assuming the engine is off). Look for something higher than 14v when engine is running.

[AJ_Spider]

12.3v to 12v is a good sign (assuming the engine is off). Look for something higher than 14v when engine is running.

I've had the battery disconnected all week and it's still showing around 12.35v on the multimeter. However I'm going to get a mobile auto electrician in tomorrow afternoon, to get to the bottom of this, as I'm not really making any headway. Wish me luck!

[AJ_Spider]

Just a quick update. I had an auto electrician around yesterday and we started going through everything. I think we did find a place for that disconnected vacuum hose – it seems to fit nicely into a connection in the bottom of the air box, so that's where it is for now (I also cut a bit off the existing connection from the inlet manifold as it had fractured at the base). The battery was checked and was fully charged and in a good state, so that has been eliminated. The car did start up but we had the same issue with stalling after taking foot off the accelerator pedal. The spark plugs (which were new last year) were checked and they have sooted up and there was residual traces of petrol in their holes. Also the gaps hadn't been set properly in any of the plugs, they were too wide. Once gaps were re-set we were also struggling to get a spark when testing no. 1 plug.

I have lent him my Haynes manual and he is going to study the relevant electrical diagram and do some more research and come back next week when we'll give it another go.

[peteracs]

Hi

This of course is a bit of a rabbit hole, once you start hard to know when to stop, but if over fuelling, it maybe the carb is flooding, has it had a refurb kit? Float can go bad and valve can leak, also assume return from carb to tank is connected and not blocked?

Poor spark on one plug may be bad lead, should be able to move leads around to check?

I assume the choke flaps are closed when engine cold?

Just my thought process.

Peter

[AJ_Spider]

Hi

This of course is a bit of a rabbit hole, once you start hard to know when to stop, but if over fuelling, it maybe the carb is flooding, has it had a refurb kit? Float can go bad and valve can leak, also assume return from carb to tank is connected and not blocked?

Poor spark on one plug may be bad lead, should be able to move leads around to check?

I assume the choke flaps are closed when engine cold?

Just my thought process.

Peter

Hi Peter,

I take your point about it being a rabbit hole, but I thought to be methodical and check everything from battery through to ignition and beyond. The auto electrician is coming back at the end of the week and he's bringing some spark testing equipment, so we should know more after that, but I will ask him to check the leads as well. There does seem to be a collection of fuel underneath where the carb is, but I thought the mechanic who worked on it last year had addressed this, but maybe not well enough? I will check the choke flaps as well, thanks for pointing this out.

I'll report back once we've checked everything further.

Andrew

[peteracs]

Hi

You do have to be methodical if you want to get to the bottom of it. I really meant you end up replacing loads of parts, some will be sensible/necessary others less so. This can amount to significant cost unfortunately.

Best of luck when your guy returns!

Peter

[AJ_Spider]

Hi

You do have to be methodical if you want to get to the bottom of it. I really meant you end up replacing loads of parts, some will be sensible/necessary others less so. This can amount to significant cost unfortunately.

Best of luck when your guy returns!

Peter

Thanks Peter,

He is over tomorrow so fingers crossed we achieve something!

Yes, I'm shooting in the dark with some of the items I've recently purchased, but they can't do any harm I'm sure.

I will report back in due course.

Andrew

[JohnFol]

I was down at BetaBoyz today and Mark had a manifold with the T piece on it.

If I remember correctly, it goes to a vacuum operated heating vent.

I'm sure someone will confirm or correct me...