stuttering probs

[Tappy]

today i made a grand tour , seems like i still have a problem (or more) after 2h drive she start sputtering like she is goin out of fuell ,only, thats not the case there's still fuell squirting in the carbs. Ive had this problem earlyer and it only appears to happen after a long ride , besides that and probably not connected is she leaking oil , also we replaced all the gaskets when the engine was out of the car , the oil i can refill untill i got time and money to check where the leak is comming from.

The stottering is what concerns me any ideas ? when she 's cold again i go and check the spark plugs maybe they can tell me something , only the odd thing is when i'm in neutral and i accelerate she just does fine she only stutters when driving the faster i go the harder she sputters

this saterday there's an oldtimer tour i'd like to participate ,its 200 km and i'm afraid she wouldnt hold up

any ideas are welcome

[launieg]

Tappy, I'm guessing here, but it sounds to me like it is "missing" under load. In other words, could it be that it is worse when you load the engine, rather than being related to speed? When you go up a hill for example, or when you accelerate hard, does it then "stutter", regardless of your speed? Perhaps I'm not explaining this very well.

Now, if you determine that it is missing under load, then it could be several things. It might be starved of fuel. Are the carb float levels correct? The plugs might be bad or gapped wrong. The advance for the timing might be incorrect. The air filter might be blocked, or some other restriction to air flow.

I'm sure others will have ideas too, but I would check these things to start with.

[Tappy]

Tappy, I'm guessing here, but it sounds to me like it is "missing" under load. In other words, could it be that it is worse when you load the engine, rather than being related to speed? When you go up a hill for example, or when you accelerate hard, does it then "stutter", regardless of your speed? Perhaps I'm not explaining this very well.

Now, if you determine that it is missing under load, then it could be several things. It might be starved of fuel. Are the carb float levels correct? The plugs might be bad or gapped wrong. The advance for the timing might be incorrect. The air filter might be blocked, or some other restriction to air flow.

I'm sure others will have ideas too, but I would check these things to start with.

he thx launie

the spark plugs are new , i just removed them and the first 2 look black the other 2 gray(like they should) i have K&n filters(new ones) so i dont think they block of air either

i'll check the timing but almost whole ignition is replaced (coil, wires,cap,rotor) and i looked 2 days ago and its set to -10 tdc however i dont rule this out completely because the ignition is an old allison (crane 700 they're called now) i never heard of it ,but can it be the controller gets overheated or something ? i still have the points dizzy i could check if its working better but then i like to borrow someones dwell meter

i'm not sure about the webers (btw i'm running 40 idf's )either , but they were adjusted (by a pro not yet a month ago)

I'm off for a ride in a few minutes , i'm wondering how she will act , my furious italiënne

Still open for suggestions

[mdrburchette]

Tappy, I believe you can rule out an ignition problem. Since your first two plugs are black I think that would indicate a problem with that first carb. You might want to make sure the float is properly set on that first carb.

[racydave]

Just a wild guess, loosten the fuel cap and try ...

[Tappy]

denise ,if its a problem with the webers i need someone to set them for me properly with special device to calibrate them first all for before putting them on the car , they might as well need a ful rebuild , sadly i dont have the funds to so now , hopefully i can get them don prperly some time soon

Just a wild guess, loosten the fuel cap and try ...

wel thats funny to say so , because i tried that also , not even knowing why , maybe this is because there's a pipe in the engine room i'm not sure where i need to connect it , its a steel (metal) pipe like the one from the fuel support , there's another i conected to the weber overflow but i never really undertood why the 3 one is , can it that it had something to do with possible prevous california smog equipment ? i believe she's a 1979 californian italian

foir the record nothing has been connected to that pipe since i've got the car , not one of the engines used this mistery pipe
does anyone have a clue , and racydave why would you ask to open the fuelcap ? or are you suggesting there's no fuel in the tank ?

[mdrburchette]

Dave is probably thinking the tank isn't breathing and letting the gas get to the carbs.
Tappy, do you have a fuel pressure regulator on the fuel line? Are you running the mechanical fuel pump? I'm going to email you a friend's email address that is a whiz with these dual carbs. If he can teach me how to tune mine over the phone, he can help you with your problem.

[spiderman2000]

Tappy,

Just my 2 cents worth......
Before you go to any great lengths or cost working on or tearing the car apart STOP. It has been my experience that this is fuel problem. First thought that crosses my mind and an issue I have had in the past which is a clogged fuel filter. Sediment collects in the fuel tank over time or it can be in the fuel you buy (water in fuel as well). First step would be to get a sample of the fuel from the fuel line and fill up a clear container about 1 cup. Let the fuel settle for about an hour or 2 and come back and look at what is in the container. If you have water in the fuel, then the two will separate in the container. The water will look milky. If this is the case then drain the fuel tank and lines and get clean fuel. If the fuel is ok, then the next step is to determine if any of the lines are cracked allowing air into the fuel. Replace fuel lines if needed. The last 2 steps are to replace the fuel filter and then check the fuel pressure between the filter and the carb. If the the pressure is low then most likely the fuel pump has issues.

Hope this helps.

[launieg]

Tappy, I agree, don't remove anything yet. Do some more diagnostics first. I'll put some thought into it, and I know others will continue to offer suggestions - do all these simple things first. I doubt that you need to spend any real money to fix this.

[Tappy]

Dave is probably thinking the tank isn't breathing and letting the gas get to the carbs.
Tappy, do you have a fuel pressure regulator on the fuel line? Are you running the mechanical fuel pump? I'm going to email you a friend's email address that is a whiz with these dual carbs. If he can teach me how to tune mine over the phone, he can help you with your problem.

a fueal pressure regulator ? i dont think so , where should it be , i might have one in the trunk i'lll take a look . Im almost sure there isn't one in the engine bay. If i dont have one do i need one ?

i'm running a mechanical pump (probably 30 years old) theres an fuel filter just below my webers , and when the car starts it fill up with fuell

Tappy,
Just my 2 cents worth......
Before you go to any great lengths or cost working on or tearing the car apart STOP. It has been my experience that this is fuel problem. First thought that crosses my mind and an issue I have had in the past which is a clogged fuel filter. Sediment collects in the fuel tank over time or it can be in the fuel you buy (water in fuel as well). First step would be to get a sample of the fuel from the fuel line and fill up a clear container about 1 cup. Let the fuel settle for about an hour or 2 and come back and look at what is in the container. If you have water in the fuel, then the two will separate in the container. The water will look milky. If this is the case then drain the fuel tank and lines and get clean fuel. If the fuel is ok, then the next step is to determine if any of the lines are cracked allowing air into the fuel. Replace fuel lines if needed. The last 2 steps are to replace the fuel filter and then check the fuel pressure between the filter and the carb. If the the pressure is low then most likely the fuel pump has issues.

Hope this helps.

i'll do a fuell test , my tank was as good as emty , before i started driving her , so first thing i did was go and get me a full tank of 98+ fuell , the only filter i'm aware of is just below the webers and looks clean , but i'll test it anyway


dont i need some kind of tester to test fuel pressure ? i'm not sure how to test this
thing is the car also stutters when i drive it slow , is it wrong to assume that fuell delivery isn't the problem then ? i would think it would only make a big difference on bigger speeds (bigger fuel consumption ?)


another remark what makes me a big fan of denises theory is thaty the webers arent set correctly (but i dont rule out fuel delivery yet) because after cooling down yesterday i pulled the plugs and cleaned them of (to be exact i only cleaned the 2 black ones , the other i just put back) , car ran again with no stuttering. ofcourse some other things thay may cause the problems would be cooled down also (still a little suspect on the electronic ignition module , but since no-one mentioned this as a probable cause , i might as well drop that idea....)

i'm gratefull you all want to help , i'll do some more testing today and get back to you guys with the results
hopefully we can determine whats happening there , under the hood

[mdrburchette]

a fueal pressure regulator ? i dont think so , where should it be , i might have one in the trunk i'lll take a look . Im almost sure there isn't one in the engine bay. If i dont have one do i need one ?

i'm running a mechanical pump (probably 30 years old) theres an fuel filter just below my webers , and when the car starts it fill up with fuell

Tappy, the 40 IDFs don't like a lot of fuel pressure. They work best with 2.5 to 3.5 lbs of pressure. The mechanical fuel pump makes around 5 lbs when idling and up to 7 lbs when driving it harder. You can do two things. Change the fuel delivery to an electric fuel pump that delivers low pressure/high volume or install a fuel pressure regulator to the line. I'm running the Holley fuel pressure regulator on both my cars. The regulators have a way to set how much pressure to run. Mine are set at 3 lbs.
After you get the pressure regulated, we need to work on getting the carbs properly synched and tuned.
Here's a pic of my regulator at the end my fuel line at the carbs:

[Tappy]

thx denise , that may explain why the first 2 idfs are getting the plugs overloaded , no ? i like the mechanical type of pump , because i have little trust in an electric system So i'll need a pressure regulator i guess. I bet it would be hard to find around here , when i ask around for a simple flushing-t or zddp in autoshops nearby they look @ me like i'm talking arabic

maybe i can work something out with ralph (lanciahf) he 's sending me some misc and i can as well ask him to combine some stuff

i'm off for another test ride to see the cooling system wants to work properly now , i'll get back to you for sure

[Tappy]

damn cooling system wont work as i have no other car now i need this one to get to the autoshop to listen if they have that pressure regulator

i made me a t-piece for filling of the cooling system , but u guess i need to drill that hole like mike suggested(in thermostat) to get rid of the air pockets , i have no other clue what it would be , lower radiator hose is still cold , its a new thermostat

when she gets hot only thing happening is that the expansion tank is overflowing

now i need her to cool down for a while temp sensor almost got to red , so screwing of the radiator cap would be desaturous

[Tappy]

colling probs solved , next thing is the pressure regulator , but my wife instructed me to to leave the car alone until after the rally :d

[mdrburchette]

Good luck with your rally Tappy.
I just got a postcard from my Aunt and Uncle in Greece. It seems they are on vacation in Munich, enjoying some of that Bavarian beer. That's not too far from you, is it?