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simon a-b

engine misfire/poor running/coolant issues?

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I haven't tested the thermostat out of the car.  So far on a cold start after waiting a little while the ally pipe gets hot so I think it's opening fine.  Wouldn't be hard to test but I reckon it's OK.  For example today when running well I could see return coolant into the header tank, so the thermostat was clearly open. 

 

Another thought, could it be possible for the needle valve to stick with the fuel pump working well?  I'd think that the pressure of the pump would clear any stuck needle valve?

 

I guess if I'm still getting fuel starvation (as evidenced by the empty float bowl) the front carb was Ok just because it was fed first from the pump?

 

I have tried before when this problem comes listening for the pump... i.e. turning the motor off, then ignition on immediately to see if the pump seems to need to pump a lot to feed the carbs.  So far it hasn't done that; just the normal click every few seconds suggesting primed carbs. 

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If the needle valve in the second carb is sticky and not letting enough fuel through then the fuel pump will sound the same, if it clears the you can hear the fuel pump go like the clappers until the float chambers are full, check the needle vale and the float levels.

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I took the floats out and the needle valves are all clear... the floats look very similar to each other in terms of dangle.  They looked to be 8.5 gram floats. 

If the floats are not set correctly I wouldn't get 60 miles of good running though?

Next time it happens I'll give the carb a tap near the needle valve and see if that makes any difference. 

My point with the fuel pressure was that it would be hard to stick with 3 psi and gravity all pushing against the 'stick'...

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Sorry for delay in sending pics of fuel filters.  I put them in despite new tanks as when I fitted the old sender the seal crumbled into the tank.  The big bits I fished out  but wanted to protect the pump.   I was wrong in that the r/h filter is just outside the rubber bung in the engine bay,  The l/h is under the tank and if I have to change it I can fit a brake pipe clamp onto the short stub of  fuel line for a coupe of minutes to stop the flow.  From the pic I need to readjust it as the inlet to the filter is bent.  After 1000 miles the only crud in the filters looks like dust and muck from the manufacturing process.

 

I got new flowlock valve from SJs but it was for a excel and I think it just needed a different fitting on it.

 

Re the cooling and rad, with 3 new fans and a 3 core rad when they kick in and I step out of the car it feels like I could cook a chicken in he door area of the car so very definitely dumping loads of heat.

 

Another thought is take the tstat out and run it up. It will just take longer to get up to temp if the flow is working  and see if  you get expected heat at the rad and the fans kick in. 

post-1261-0-72706200-1410014030.jpg

post-1261-0-36189200-1410014046.jpg

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It is possible for the needle valve to stick shut if the needle is very worn.

 

It might be worth establishing what type of Lumenition you have, the regular (which was originally fitted) which needs a ballasted coil or the sport which does not. The distributor optical pickup must match and there are two types of pickups on the original system, it must be the correct version.

 

Did you replace the entire system as a unit? If not, maybe there is some mismatch.

 

A fuel related misfire sounds different to an electrical one. The electrical would be accompanied by a lot of popping and banging when unburnt fuel eventually ignites, but a fuel related would be "quieter"

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That filter install looks good.  I've got what looks to be original pipes between tanks and to pump... I'd have to cut them to adapt filters into there.  I've put one in from where the solenoid was to the carbs, but from what I've read more filters is better!

 

The Lumenition I have is the regular unit, white plastic where the wires come out of the module and unfinished alloy colour.  I fitted it myself, replacing retro-fitted points done by the PO.  This was before the reno (around 5 years ago) with no problems.  So since the Lumenition was a boxed kit, I think the pickup must be correct. 

 

I have fitted a ballast resistor and two feeds to the coil, one for starting at 12v and one for running going through the ballast resistor.  Coil runs cool to touch. 

 

From your description of 'quieter' missfire I'd say it is fuel not ignition, there's almost no popping/backfire.  All this is with periods, some quite long, of 'good running', so gross errors like wrong parts can be fairly confidently ruled out. 

 

Since it runs still when missfiring it can't be the pump actually stopping, as this would kill the engine completely.  How do you check needle wear?  Just take it out and look? 

 

And would that clear if I tap on the carb when the missfire happens?

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A confession...

 

I may have been wasting the court's time.

 

When I got the little spigots to balance the carbs, I left them in, capped with a bit of fuel hose.  Today I realised that the missfire started after I had fitted them (a long time after, but only after). With all the talk of vacuum leaks I took them out and re-fitted the screws, sealing them up again. 

 

I also took the rear pipe off the block and filled there with coolant, took a couple of times to get the block re-filled. 

 

So far so good, took the car for a quick spin before dinner, no problems, and just now did another 35kms going hard and no issues.  Only may have been wasting in case I haven't fixed it (or just put it back properly, doh!).

 

Along the way I've corrected the coil wiring, cleaned and refitted the fuel pump and put a decent filter in line so it hasn't all been pointless. 

 

I do hope that was the issue, and once again I feel like a bit of a dil for not thinking of it!

 

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Self-inflicted wounds are a Court martial offence....(!)

 

Seriously, any problems that develop after work has been done are quite likely to be due to whatever has just been done... we've all been there...... Let's hope you are right!!


Scientists investigate that which already is; Engineers create that which has never been." - Albert Einstein

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I agree with the 'just done work'... but there's been 5 years of that! And the issue was days and many ks after the balance. I guess the rubber just leaked enough when warm, I had clamps like I would for water/fuel but seems not enough. I think they may have actually leaked around the spigot thread/mating surface rather than the rubber? Makes me wonder about how they perform when balancing.

Anyway, very thankful, drove to and from work today, no probs...

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This topic has been quite helpful Simon. My car was running a little hotter than usual and you made mention of the flow from the little expansion pipe back to the reservoir tank. I checked this with my car and there was no flow so I pulled off the hose to reveal a complete blockage. All fixed now.

Credits go you you mate, thanks!

Iain

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This forum is great, isn't it... just reading threads, contributing where we can, offering moral support and hard won experience makes this so much easier!

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We few....we happy few.....we band of brothers.......etc.etc.

 

Not many of us; thanks to the Interweb (and some bloke called Bibs) we can communicate!!

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Scientists investigate that which already is; Engineers create that which has never been." - Albert Einstein

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I would add communicate across the world, I can't count the time I've saved working on my car just by reading through the threads before hand.


Something I learned about cars or planes, it all works until it doesn't anymore...sometime there is no way around it!

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Definitely.

 

My first time around owning an Esprit was from 1984 to 1992 (dry sump "white Essex"). Before the benefit of the internet it was a very different challenge looking after an Esprit!

 

Having come back here after all these years I can see that all the problems I had (eg cracked manifold, sticking Wastegate, gearbox leaks, crap gear linkage, even a broken differential gear tooth) were not unique to my car!

 

I suppose its the same on any car forum, every problem has been experienced by someone else and in some cases pretty much everyone else!

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