2l ford pinto with twin Weber overrun problem
Discussion
Hi, I have a 94 transit with a 2l pinto engine and twin Weber carb. I bought it 2 years ago and it had this engine overrun then. I had the top end rebuilt about 8 months ago which has solved the power issues but the overrun persists. My mechanic has set the timing several times, we've had it all over the place and nothing seems to solve this overrun. It also seems to be using a lot of fuel though I've just had another guy run it through the emissions test and it's passed ok. We're thinking the problem could be caused by some problem with the carb? (He did a full strip down when he rebuilt the engine) I made a video here of what it's doing https://youtu.be/hTjunjyyAXY could the choke pull off (it's manual choke but I think that's what the sealed unit here connected by the black tube is)be causing this, because it looks like that is continuing to pump the lever after the engine is turned off. I hope that makes sense...
Polly Grigora said:
Before getting well involved
Have you checked if there is a voltage remaining at the ignition coil positive terminal after turning the ignition off?
Carry out the above test while engine is over running
texaxile said:
My capri used to do this, turns out the cam belt timing was 1 tooth out, easy to check so have a look at that. Was also a real b
h to start sometimes, mostly from hot.
Same set up, 2.0 pinto with a twin choke Weber.
This could be an issue, obvious when it was rebuilt I imagine it's quite easy to get this slightly wrong...h to start sometimes, mostly from hot.Same set up, 2.0 pinto with a twin choke Weber.
I've a distant bell tolling when new they had an anti-dieseling device fitted ? This was a length of hose with a solenoid one end and the other connected to the inlet manifold, on switching off the solenoid vented the inlet to atmosphere.
Didn't they also have auto-choke ? This hasn't, I suspect a replacement carb has been fitted and the ADD has been removed before you acquired it as it's been a persistent problem.
You could hear the air venting in to the manifold every time it was turned off which always amused me as a crude method of curing the problem, Iirc? Trannys were not the only model from Ford that had this fitted in that era ? But it is a few years ago and a challenge on my ageing grey matter.
Didn't they also have auto-choke ? This hasn't, I suspect a replacement carb has been fitted and the ADD has been removed before you acquired it as it's been a persistent problem.
You could hear the air venting in to the manifold every time it was turned off which always amused me as a crude method of curing the problem, Iirc? Trannys were not the only model from Ford that had this fitted in that era ? But it is a few years ago and a challenge on my ageing grey matter.
Cheesley said:
E-bmw said:
Link doesn't work for me.
Have you checked the fuel shut off solenoid on the carb?
No, I'll track it and see. Would it be obvious by looking at it if that was the problem?Have you checked the fuel shut off solenoid on the carb?
Next time it happens see if the wire loses 12v when turned off.
Maxdecel said:
I've a distant bell tolling when new they had an anti-dieseling device fitted ? This was a length of hose with a solenoid one end and the other connected to the inlet manifold, on switching off the solenoid vented the inlet to atmosphere.
Didn't they also have auto-choke ? This hasn't, I suspect a replacement carb has been fitted and the ADD has been removed before you acquired it as it's been a persistent problem.
You could hear the air venting in to the manifold every time it was turned off which always amused me as a crude method of curing the problem, Iirc? Trannys were not the only model from Ford that had this fitted in that era ? But it is a few years ago and a challenge on my ageing grey matter.
This is new information for me. I'll see if I can find anymore out. Do you know if there's a way to find out what the carb would've been originally. I know slapping twin Weber's on willy nilly was a big thing for a while. Everyone seemed to want to be doing it... And not all of those people were clued up on whether they should be or not.Didn't they also have auto-choke ? This hasn't, I suspect a replacement carb has been fitted and the ADD has been removed before you acquired it as it's been a persistent problem.
You could hear the air venting in to the manifold every time it was turned off which always amused me as a crude method of curing the problem, Iirc? Trannys were not the only model from Ford that had this fitted in that era ? But it is a few years ago and a challenge on my ageing grey matter.
GreenV8S said:
I'd have thought an ignition problem was far more likely than a carb problem.
Anything back-feeding the ignition relay or directly back-feeding the ignition circuit could cause that.
Is the ignition switched supply powering off when you turn the ignition switch off?
Yes, electrics turn off with the ignition as you'd expect.Anything back-feeding the ignition relay or directly back-feeding the ignition circuit could cause that.
Is the ignition switched supply powering off when you turn the ignition switch off?
Cheesley said:
This is new information for me. I'll see if I can find anymore out. Do you know if there's a way to find out what the carb would've been originally. I know slapping twin Weber's on willy nilly was a big thing for a while. Everyone seemed to want to be doing it... And not all of those people were clued up on whether they should be or not.
It is just a distant recollection, I think the connection was made to a T piece on the inlet manifold? It's quite possible the engine/inlet manifold has been replaced with a similar version not fitted with ADD (Don't recall earlier Pinto's having one) that would explain the absence.BTW - This isn't "Twin Webers" it's a Twin Choke downdraught, twin Weber's is a reference generally to a pair of DCOE's which are side draught.
Like these
Maxdecel said:
It is just a distant recollection, I think the connection was made to a T piece on the inlet manifold? It's quite possible the engine/inlet manifold has been replaced with a similar version not fitted with ADD (Don't recall earlier Pinto's having one) that would explain the absence.
BTW - This isn't "Twin Webers" it's a Twin Choke downdraught, twin Weber's is a reference generally to a pair of DCOE's which are side draught.
Like these
Thank you for the extra info and for clarifying my confusion. I just emailed the main ford CS to see if they could supply me with original carb information. I'm not sure anything will come of that but doesn't cost me to try and it might give insight into what's going on here. It's using a lot of fuel too (I know it's never gonna be super economical but I have a feeling it should be doing better than it is) thanks a lot for taking the time to respond. I really do appreciate every little piece of information people are willing to share. Have a great weekend!BTW - This isn't "Twin Webers" it's a Twin Choke downdraught, twin Weber's is a reference generally to a pair of DCOE's which are side draught.
Like these
Cheesley said:
I have taken to stalling it when it's really bad... I'm not sure if this is good to be doing or not ..
Better than letting it run on by dieseling. IIRC in similar circumstances the BMC A series engine could stall, fire immediately and run backwards with the ignition off. Cheesley said:
Thank you for the extra info and for clarifying my confusion. I just emailed the main ford CS to see if they could supply me with original carb information. I'm not sure anything will come of that but doesn't cost me to try and it might give insight into what's going on here. It's using a lot of fuel too (I know it's never gonna be super economical but I have a feeling it should be doing better than it is) thanks a lot for taking the time to respond. I really do appreciate every little piece of information people are willing to share. Have a great weekend!
Good to know the little knowledge I have may be some use
HTH, Not your model year but you get my drift - https://ford.7zap.com/en/transport/76/no/1/1501/15...As for mpg they never were good, not the most slippery bodyshape.
1-May be incorrect replacement carb so jetted incorrectly.
2-Does it have vacuum advance ? I couldn't see a vac pipe from your vid ....however I wasn't looking for it, that makes a difference on Motorway type journeys where the throttle position stays relatively constant.
DickyC said:
Just checked. The engine would need to be flooded for it to run backwards. Apologies for going off topic.
I don't think you're wrong, that's why the engine kicks about, the violent knocking is detonation trying to force the piston in a reverse direction.Iirc? That could be a hot spot firing the little fuel that remains as the engine is switched off being ignited creating a weak mixture which burns slowly, so slow it fires when the piston is way past TDC. I think the violent shaking before it eventually stops is the beginning of an attempt to run backwards.
But we need an emissions engineer to slap my theory down for that, I have no experience in PU / iCE Development.
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