Carb issue?

[lavamatrix]

the vacuum connection on the carb is plugged, good to know it isnt necessary to function normally as I dont know how to connect it correctly.

I get the engine light but no oil light at any point. I went ahead and connected that wire which was unplugged near the oil switch with no effect. So I guess either the switch is bad or the wiring is.

Quote:

take a temporary wire from the + post of the battery and connect to the + terminal of the ignition coil.

So this would bypass any safety switch like the oil switch? I am going to change the oil and put a new filter on and then try this. Hopefully if it is that oil switch it is just a bad one and not the wiring as the wiring seems like a daunting task to grapple with.

Once again many thanks.

[sparky_spit]

2258 wrote:

So this would bypass any safety switch like the oil switch?  

Yes. But that's assuming there is some sort of safety switch associated with the oil pressure switch on North American cars. I don't know if there is or not, but at least it would rule out any doubts in this area. Obviously you cannot leave the temporary wire from the battery + to the coil + in place all the time, as your ignition circuit will be permanently live, but it is a good way to prove, or disprove, any fault in the +12v igniton feed to the coil.

[HMaze]

(evil)

Hi Lavamatrix,

I would sugest that you first look at a wiring diagram of your model.
Does it have the smith's module still connected?

The oil pressure switch is a trigger.
There should be 3 wires on it.
Black, White/Brown and White/Purple.

With no oil pressure Black is connected to White/Brown, which is the OIL light.
With oil pressure, it disconnects Black and White/Brown and connects Black with White/Purple, which is the anti run on valve.
Black is Ground.
Your Spitfire uses a special ignition switch (with 6 (8) connections). With the ignition Off there should be 12 volt on one wire of the anti run on valve. With the ignition on there should be no current on the anti run on valve.

The distributor has a retard vacuum on manifold vacuum.
Your ignition timing should be 4° ATDC with the vacuum attached!!!
So the vaccum is at least needed for timing the ignition right.

The mecanical disconnection of the EGR and AIS service counters should have no influence on the ignition, because they are only switches and warning lights.

The EGR seems to be disconnected allready.

Cheers,
Harry

[lavamatrix]

yes smiths module is connected as far as I can tell (it sits behind the center dash correct?)

Researching now about EGR and AIS as I dont know what they are  :-/

The wiring for the oil switch is all there, black + white/brown + white/purple (which was the one originally disconnected). If they are working or connected to the right terminals I dont know.

I have the wiring diagram that is floating around the internet http://www.triumphspitfire.com/images/wiring/78diagram.jpg

Going to try the bypass method right now. Hopefully it works.

[HMaze]

(evil)

Your wiring diagram is for a 78 federal.

here is the one for the 75 federal:

http://www.triumphspitfire.com/images/wiring/75diagram.jpg

It doesnt fit exactly to your californian model, but more close than the 78 diagram.

When i look at your picture of the oil pressure switch, the black should be on the bottom, white/brown on the left, and white/purple on the top.
But you can also measure the connections with test bulb ore a volt/ammeter, as discribed above.

EGR - exhaust gas recirculation. A big valve at the exhaust header with a connection to the top of the inlet manifold. Actuated by a vacuum pipe. Recirculates exhaust gases back into the inlet manifold. (NOX reduction)

AIS - Air injection system. Airpump and several valves to blow in air right behind the exhaust valves to get cleaner exhaust gases. (HC CO reduction)

Charcoal canister - the vents of the fuel tank, the carburetor and the crankcase ventilation are connected to the canister and vented into the inlet manifold. Fresh air is added through the anti run on valve in runing condition. When the ignition is shut off, the anti run on valve closes, and the manifold vacuum is applied to the canister and the carburetor float vent, which shuts the fuel supply to the engine off. When the oil pressure gets to zero, the anti run on valve opens again. (HC reduction)

The Smith's module normally only allows to start the engine when the driver sits in the seat and the seatbelt is closed. If a passenger is in the car, he also has to use the seatbelt....Plus it has some other nasty features too.

To deactivate the smith's module, pull the 12 pin plug out of the module.
then shortcut the pin 11 (White/Red) and 12 (White/orange) in the plug.

Ignition Timing is 2°ATDC not 4 (Sorry, my fault)

Maybe your waterheated choke isn't adjusted right, so the engine dies through enrichment.

here is a pdf about the zs water choke:

http://www.sterlingbritishmotoringsociety.org/files/choke.pdf

Be carefull with the bypass. Your system incorporates a balast resistor in the wiring!
A bypass will give the full 12 volts on a coil which only needs 6-9volts!

Cheers.
Harry

[firebobby]

When the engine stops after 10 seconds, will it start straight away, i mean the instant it dies will it restart and run for another 10 seconds or do you have to wait.

[lavamatrix]

bypass didnt work, car wouldnt start (it just kept turning with no ignition).

after looking through the wiring diagram the fact that there is no oil pressure light means at least one of the following

the bulb is out
the brown white wire is bad
the oil switch is bad
or there is no oil pressure and thus the "Anti Run On Sol." is activated

There is oil... no leaks as far as I can see. So I would think there would be oil pressure? Also if there was no oil pressure and the Anti Run was activated why would it start and then shut off? Shouldnt it just never start? Since that white purple wire was disconnected in the first place (bypassing that switch) then that cant be the issue since the Anti Run couldnt be activated. Also I wouldnt think the ignition could shut the car off correct? Once it starts the ignition's job is done and it doesnt do anything correct?

So it seems that the oil switch, even if it isnt working properly (something isnt due to the lack of the light coming on), wouldnt be the cause of the shut off.

What else would just cause it to abruptly shut off after a few seconds? Not enough fuel or too much fuel comes to mind. Checking the float bowls shows there is fuel getting there. Nothing is leaking out of the carb so it doesnt seem like too much fuel. I still wonder about the exhaust but cant do anything about that until my new system comes in a few weeks. Could the choke be bad? It is an automatic water choke. Originally when I pulled the carb to rebuild it the water choke system was all clogged up. I cleaned it out but maybe it still isnt working? I have another carb with a manual choke but I dont have the cable to operate it. Can I use it without the cable temporarily?

[lavamatrix]

firebobby wrote:

When the engine stops after 10 seconds, will it start straight away, i mean the instant it dies will it restart and run for another 10 seconds or do you have to wait.

starts right away

[drofgum]

lavamatrix,
I'm surprised the engine doesn't run when bypassed, but re-reading sparky spit's post it could be misinterpreted and get one to remove all of the original coil wires instead of only those on the + or SW side.Is this how you bypassed it?
"Starts right away" is exactly what I expected.
Try earthing (grounding) the white/brown wire with the ignition switched on; does the green oil pressure light come on?
Also earth the white/purple wire then try starting the engine: does it start, and does it still stop after 10 seconds?  
                                                                  Cheers,
                                                                  Paul

[HMaze]

"after looking through the wiring diagram the fact that there is no oil pressure light means at least one of the following

the bulb is out - yes or it is burned
the brown white wire is bad - yes
the oil switch is bad - yes
or there is no oil pressure and thus the "Anti Run On Sol." is activated -NO"

the PDWA Bulb is out, burned or not connected
the bulb doesn't get current.

Cheers,
Harry

[junkuser]

Have not encountered these "anti run-on valves".

Do they work by shutting the fuel off to the carburetor or by bleeding air into the manifold?

If they shut the fuel of then I would imagine that they would have to open when the starter is powered to allow starting and kept open via some other circuit when the engine is running.

IF this is the case then sufficient fuel could be let while the starter is in use to allow the engine to run briefly but stop if the the circuit that maintains power to the valve does not work.

Maybe this is all rubbish but just came to mind from the suggestions that there maybe a safety circuit that shuts the engine down if there is no oil pressure.

Jumping power to the shut-off valve to keep it in the running position would rule it out as the problem.

Criticisms and/or further enlightenment welcome.

[junkuser]

" However I wonder why would the intake manifold need to be cooled?"

Actually the water to the manifold is to HEAT it to overcome the cooling of the carburetor caused by the vaporising of the fuel whilst engine is running.

Without some type of heat supply carburetors can get cold enough for ice to form.

[lavamatrix]

Havent tried the new suggestions since I had to take a break from my spit this afternoon as she was driving me nuts!

I have attached the pic of the wiring diagram that indicates the anti run on valve. I dont know where it actually is or how it works, just going off what the diagram shows.

I will try the bypass with the single wire to the battery method again. I did leave the electronic starter (that red box) connected since I assumed that was needed to be powered for the car to start but I will try to disconnect that as well.

I will also try grounding those connections as suggested to see what happens.

[HMaze]

(evil)

I discribed the function of the anti run on valve in my earlier posts.
There is no such thing as a safety shut down with no oil pressure.

http://www.triumphspitfire.com/images/emissions/75-77emissions2.jpg

As you can see from the wiring diagram, the OIL bulb can also be off and the BRAKE (PDWA bulb) on, when the PDWA is active or the handbrake is on.

Cheers,
Harry

[lavamatrix]

thanks harry been looking for a diagram explaining what that system is.

Just one question the #1 line is connected to the engine loosely, is that ok or does that need to be a tight seal?

[HMaze]

(evil)

all connections should be air tight.
With older hoses a hose clamp is always a good idea. ;)

Cheers,
Harry

[lavamatrix]

wow well when I went to take off the intake manifold and carb to put in the new gasket I found a HUGE crack in the exhaust manifold! Well I feel fairly certain that this crack was not there when I first took the carb and manifold off. Maybe it was a hair line crack that just got bigger? What would cause that to happen?

Luckily I already had ordered a new Double S 4-2-1 header and matching exhaust a week and a half ago but my fear is that something caused the crack and I dont want to blow up my new header (which hasnt arrived yet).

The crack is massive and looks like the pipe almost is completely severed (crack feels like it goes all the way around. In addition the tube next to it looks like it has a small crack as well.

Another question, when I changed out the plugs the old plugs I started to wonder if the spark plug wires were in the correct order. The wires are numbered 1,2,3,4 and were in order from left to right. Also the old plugs were very dirty (black) so too rich right? The wires are old themselves so I think it would be good to get a replacement set as well (one of them fits very loose).  

Also I realized why the hard wire from the ignition core to the battery didnt work the first time. I have an electric fuel pump, if it isnt powered no gas, no start. However if I feed the pump into the direct line it will just flow nonstop and I would end up flooding the engine before I could start it right?

Looks like I got sold a lemon :(

[lavamatrix]

wires

[junkuser]

Thank you Harry.   So it is an air bleed system.

From the section of a wiring diagram posted above it would appear that the anti run-on solenoid is "earthed" via the oil pressure sender when pressure is present and the "earthing" of the oil warning lamp is interrupted.

Was more than one system used or am I misinterpreting the wiring diagram?

Just looks to me as though, with no oil pressure, the warning lamp is "earthed" and with pressure, the anti run-on solenoid is "earthed".

Further enlightenment on how it all works would be appreciated.

Mal.

[drofgum]

lavamatrix,
No, running the fuel pump won't flood the engine; that is what the float bowl and needle and seat valve (not the metering needle)are for.
The firing order is right. If the wires are old and perished then fitting good quality new ones is a good idea.
Yes the black deposits on the plugs indicate rich running, but remember you haven't been able to run the engine long enough to get it warmed up; so you may be running with the choke in operation.
You might try hooking a test light between the coil +terminal and earth; then start the engine. Watch the light to see if it shuts off when the engine starts to slow down. Or does it stay on until the engine has stopped turning?
                                                                             Good luck,
                                                                             Paul

[junkuser]

Oops, wrong again.

Apparently that type of anti run-on valve works by reducing pressure in float bowl to prevent fuel going up the jet according to

http://www.templeoftriumph.org/tsoa/TSOASep74.pdf   Page 3.

This means the system does not require any special circuit to cancel during starting as it requires manifold depression for it to operate, apparently more than is present whilst cranking.   Very clever.

May try it on my my "Mk 1" Spit as same principal should work with twin Stromberg CDSs.

This suggests to me that Lavamatrix's problem may be that the connection from the anti run-on valve to the oil pressure sender is missing allowing sufficient fuel for the engine to start but be starved when the manifold depression is transmitted to the float bowl.

Removing the hose that connects to the float bowl vent should allow the engine to keep running if this is the case.

[junkuser]

More about this type of system on

http://www.mgb-stuff.org.uk/fueltext.htm#runonna2

The system functions similarly but its activation is different.

[lavamatrix]

wow you guys are amazing. Going to read those links to familiarize myself with that switch.

Unfortunately I wont be able to test anything out for a while. Since the header is cracked and I have a new one on the way I began to remove the old exhaust system. everything is disconnected with two big problems. One it seems the previous owner knew about the bad header and tried to remove it. Apparently he couldnt free one of the nuts and cut the stem of the the thread. So this entire time not only was there probably a crack in the header but it wasnt properly secured (since only three nuts held it in place) so it was leaking from the bottom. So now I have to try to get that piece out, first I will try to use some penetrating oil with some vice grips (doubt that will work). If that doesnt do it I think I have to have someone come out and tap the stem out since I dont know if I can do that myself (seems really easy to make a mistake).

The second and bigger problem is that, as far as I can tell, I cant remove the old exhaust manifold/header without removing the engine (or at least lifting it). The only thing I think I can do other then moving the engine is having the manifold cut apart but then the new manifold probably will have the same issue.  

So my guess is that the previous owner tried to replace the exhaust manifold, realized what I just realized, and just slapped it back on. Going to contact him and ask him about it. Really a horrible thing to do on his part if he knew about this issue.

Thanks again everyone for your amazing help. I am learning so much thanks to all of you.

[junkuser]

Sounds as though you could do with a hand.
A bit far for me from "Down Under" unfortunately.

You may be able to get that broken bolt out.   Try tapping it gently on the end several times plus penetrating oil of some type, repeating this treatment several time over a 24 hour period, may make it possible to remove it with good multigrips or very tightly adjusted vicegrips.
This assumes you do not have the facilities to weld a nut onto it which is MUCH better if possible.

Cutting off, drilling and re-tapping is much more difficult and fraught with pitfalls and should only be a last resort.  

Fight on, the end result is worth it.

[HMaze]

(evil)

@ junkuser and of course lavamatrix,

here is more read about the evaporation loss control system on triumphs.

http://www.mv.com/ipusers/last/emissions/booklet.pdf
Anti run on at page 52 ff.

It's an earlier system (1973), but the principle is the same.
Also a good read about the features of the zs carb.

Cheers,
Harry

PS Your header looks like an aftermarket 4-1. Typical US, but not very efficient.
You can try to crack the nut with a chissel, or carefully cut it with a dremel or similar tool.