131mirafiori forum

My silver S3 Super is just back from getting a big service, the 1600/TC didn't have electronic ignition :'( it was only on 2000/TC.

I was very lucky to find someone with a good Bosch electronic ignition system & my mechanic fit it along with new Magnecor leads :) it starts better & runs better too :)

(http://i739.photobucket.com/albums/xx34/minicacj/Mobile%20Uploads/photo1_zps0b983201.jpg) (http://s739.photobucket.com/user/minicacj/media/Mobile%20Uploads/photo1_zps0b983201.jpg.html)

(http://i739.photobucket.com/albums/xx34/minicacj/Mobile%20Uploads/photo2_zps6db27b3b.jpg) (http://s739.photobucket.com/user/minicacj/media/Mobile%20Uploads/photo2_zps6db27b3b.jpg.html)

(http://i739.photobucket.com/albums/xx34/minicacj/Mobile%20Uploads/photo3_zpse6ee49be.jpg) (http://s739.photobucket.com/user/minicacj/media/Mobile%20Uploads/photo3_zpse6ee49be.jpg.html)

(http://i739.photobucket.com/albums/xx34/minicacj/Mobile%20Uploads/photo5_zpse431339d.jpg) (http://s739.photobucket.com/user/minicacj/media/Mobile%20Uploads/photo5_zpse431339d.jpg.html)

Getting rid of points is one modification I think any older car should get :D

It had the original magneti marelli points, spark plugs :o The timing belt was the original one too :o It only has 21000 miles on it.

Well done Christopher Bosch is the best ignition for 131s ;D
car looks really well very very clean underneath ;)

I have an occasional problem re-starting my engine when hot . It is a 1600t/c which has been put in a 1975 Tvr . I was wondering if switching to electronic ignition would help/ cure this problem ?. Fairly sure that fuel is getting through but I usually get annoyed when this happens so may not have checked properly , I did have a problem with lack of air to the carb but I think I have fixed this with some additional ducting . New points , coil,  plugs and leads 2 years ago . Advice as to where to start tracking down the problem would be appreciated .

Need to see what's missing when the problem occurs. It could be lack of fuel or lack of a spark.

This might sound stupid , but I have a cheap inline fuel filter between pump and carb , it seems to me when I have the problem with staring this is completely full . When the car has been sat for a while this level drops and then the car will start . Is the pump running at too high a pressure and when filter is full it will not run and so does not pump?. Pump seems not to be running when I have this happen and withdrawing a small amount of fuel enables the car to start . Am i correct in assuming this is creating a vacuum and all I might need is a pressure regulator?.

What type of pump is fitted?

I have fitted an electric fuel pump , not sure what it means exactly but it is an interrupter type pressure 4-6psi . I fitted this because the original seemed to be lacking on high demand , this one is more than capable , still a little bit short if you really push !, I am thinking now that I should fit a pressure regulator as originally advised , what do you think?.

What carb(s) is the engine running?

Are you running a return line from the carb to the tank? Webers only like 2-3 psi, I've got twin IDFs on my 2 litre, this is the reg I use:
http://www.ebay.com.au/itm/HO12-804-Holley-Fuel-Pressure-Regulator-Tumble-Polished-1-4-psi-Universal-/321425530809?pt=AU_Car_Parts_Accessories&hash=item4ad6745fb9

The carb is a weber 32Adf .I am assuming from your advice that I should use a pressure regulator to reduce the flow to 2-3psi . I can get one locally which is adjustable , this what I was going to do and hope this fixes the problem , anything I need to now about which one I should use as there are two sorts available.

On the standard carb I'd just use the standard mechanical pump. As long as it is functioning correctly it should do the job fine. When I had an electric pump (with twin 40 Dellortos) I had a filter king regulator fitted. I Did set the pressure but can't remember what to now.

Mechanical pump was not working when I got the car , the electric pump fitted was poor and did not feed enough fuel at high revs this one does supply enough fuel but maybe at cost of my starting problem. There are no issues when general running in fact goes very well and I would not want to reduce pressure too much if this causes loss of fuel delievery at high revs . I have seen a data sheet on this forum which implies that the mechanical pump was set at 6psi , how come 4-6 is too much?.

I have tried fitting a pressure regulator , set at 2 psi , car still pulls very well no problem . I still have a problem starting but only when the engine is hot .
Is it obvious that I could try reducing pressure still further as fuel filter is still over full , and also I have noticed that when I have this problem the fuel pump seems not to work , I was wondering if float level might be too high as I have adjusted to make sure high flow passages are covered , no problem with fuel over topping the carb , and I was running the 4-6 psi pump unregulated for 6 months .
A fiat x/19 owner suggested I should look at the air in the carb being too hot as they have this problem ?, also anyone know where I can get I proper air box as shown in the picture at the start of this thread as I am sure that would be a help to get more air into the carb.
Any advice would be appreciated.

Thoughts,

Mixture to rich for a hot engine.

Pore spark,   also check rotor arm resistor.

Is starter turning engine fast enough.

I have some doubts over the starter as now and again it makes the clunking noise as though it is seized , but always then starts . I was going to replace last year but battery tuned out to be a fault , not high enough crank rate . If was to replace starter what would you suggest ?.
The mixture maybe a bit rich so I could try leaning out a bit . I had plugs out recently they weren't too bad so not sure if mixture is issue , but I suppose its an easy thing to try.
Relating to the mixture I would like to get more air in as this would improve the mix . At the moment I have a 9inch by 30mm speedograph air filter . This is obviously not correct or suffiecent , ideally I would like to fit correct air box , if anyone knows where to get one.
I put new rotor points and condenser in early last year .That was why I started this thread to see if electronic ignition might fix problem.
What do you think of fuel pressure lowering or float level in carb ?, to be fair problem has presented fairly consistently before carb service and with previous fuel pump , so not sure if this is relevant .
Not sure where to go next ?.

Or borrow a few bits and do some swapping

Starter and earth connections. Check cranking current draw for the starter. I would have thought around 150/160 ish amps.

What does this mean? The main jets draw from the bottom of the float bowl. Put the float level back to what it's supposed to be, simple to do, no cost and it's a proper base to start fault finding.

Absolutely TAS131       would get a very nice cold start as it would be rich, and a very pore Hoot start due to being over rich when worm.   Nicely spotted there TAS and even if its not the fix, its a good start as you say.   :P

HI Tas.


I understand the initial key problem is starting.

Have you checked the plugs for flooding?
   
Fuel pressure is very important and will effect both running as well as starting. It would seem you have  pump which is for fuel injected engines.

But so are the plugs, the points, the coil, the distributor, the condenser the leads, ....  this cam be done by checking if the spark looks good...   

First try to see if the problem is fuel or electricity related . You an eliminate electric as the problem by checking the spark all the way from the coil through the distributor and finally all plugs.  When you are at it, take the plugs out and see what color are the electrodes. This will either confirm or deny the problem is electrical.  (Though it seems to me to be fuel rather then electrical problem.) But do not guess - test !

The best tool to test if the engine is running on too rich mixture is Colortune http://www.gunson.co.uk/item.aspx?code=G4074
And it seems to be pump related ...

RE: fuel pump:

I strongly recommend Facet Red Top. I use it with two Weber 44 IDF,s and it works perfectly. It was recommended to me by Guy Croft and he was absolutely right. I use  a 124 spider fuel filter as used in the fuel injected engines (very fine!)

I will use the setup as well with my 124 spider when I install a new engine. These pumps are readily available in automotive stores. They were specially designed for carbureted engines and they do not require any pressure regulator at all.

RE: Starter:
Get a Gear Reduction Starter. There is no better ! I got mine from Allisons Automotive (http://www.allisonsautomotive.com/products.html)

RE : electronic ignition
I have a Magneti Marelli electronic ignition and have absolutely no problems. I also hear that the Bosch ignition is even better.

RE: fiddling with fuel level in the carbs : run the new  pump and make any adjustments if required.

             

Thanks for all the advice guys . Just to clear up a few things the starting issue is only a problem when engine is hot and has been running for 30mins plus , and seems to start ok after a rest .
I tried to reset float to Haynes manual levels this resulting in the car overtopping with fuel . I have adjusted the float level through trial and error so carb runs very well , too low and it seemed to run out of puff anywhere .I am generally happy with how car drives and am getting around 32mpg so I do not think that I am burning too much fuel , however , I am open to the idea that it is running rich , I have a colourtune so will give that a go .
I am unclear how float level leads to the mixture being too rich?, can I not just adjust air/fuel mixture screw .
Electrically when I had the car first I replaced plugs, leads ,points , condenser rotor arm distributor cover and coil , but got them from local motor factors , I am now wondering if I should invest in more appropriate items for the engine from a specialist supplier ?, seen that someone like micks parts seems to carry a lot of 131 parts , can anyone recommend someone I should go to .
Plug electrodes seemed fine when I had them out a few weeks ago , any ideas would be a help , but really generally the engine is running very well , went round castle coombe with it a few weeks ago comment was that it sounded savage! , maybe your right too much fuel!.

We can come with many ideas but we do not see the engine and  know anything about its history, modifications etc. so 90% of the advise we will give you will be addressing a wrong issue.

The best and in my view only approach is to do the diagnosis by a step by step elimination process , going from the through the list (below).

1.Electric: timing, points, gap, condenser, coil, distributor, advance cables, plugs (adjust, clean, replace) Make sure you put in NEW PLUGS and a new condenser !!!)

2. Mechanics: check compression on all cylinders

3. Fuel:
a/ carburetor (clean, tighten all screws, adjust mixture, air blow all jets, etc.)        
b/ fuel pump: replace with Facet Red Top
c/ put new fuel filter

Of all these things are working fine the car must start. Just make sure that all electrical accessories including the lights are OFF.  

BTW remember that when the engine is hot and gives you problem starting you start with the gas pedal fully depressed - all the way to the floor !

Unless this is done systematically without skipping any single item the whole process logic will be compromised and you run the risk of a wrong conclusion.

Anybody who thinks there is any other is dead wrong.  
    
Miro

Sorry I did not get back in touch sooner but the problem appears to be with the coil . I got a ht lead tester and no spark!.
As said previously I need to check through methodically rather than clutch at straws.
Thanks for the all the advice hopefully I will learn next time .
Going back to the start of the thread do magnecor make a standard set of leads for 131 1600t/c ? , I had a marelli distributor cover originally so assume that the distributor is also marelli . I put new distributor points and leads on 2 years ago but only from local motor factors , can anyone suggest where best to get original spares . The coil probably failed due to not being correct for the engine so I would like to eliminate this potential problem.