Pembleton plug leads and problems

[Sinbad]

Hi Guys - I have started again to try and finish my project. I’m still having problems getting it to run correctly. I fitted bougicord leads from ECAS. However the inline spark plug connection places the leads very close to the exhaust manifold. Can angled spark plug adapters be bought? Obviously I do not want to cut the leads and screw in a new cap. In addition any suggestions of suppliers of suitable plug leads with 90 degree caps would be appreciated. ECAS indicate it is critical to use bougicord.
Bess starts up ok, runs although at times misfires when revved up. However when hot she dies and will not start.
I have 123+TUNE electronic ignition fitted (timing checks good with strobe). New Dellorto PHBH28 carbs. Resin coil, I have utilised a Facet solid state pump pumping through a Fuel King regulator and filter. I have checked output of fuel to the carbs plus a gauge reading of 2.5psi. I have also adjusted the regulator to various settings to no avail.

I have checked the compression at near side cylinder 11.2bar, offside cylinder 11.8bar. I have fitted a lightweight alternator with built in voltage regulator which sometimes indicates a voltage of 14.2V. I thought the voltage might be a problem for the 123 ignition but on reading the 123 specs the max voltage is 15V. I will try refitting the points though.

On reading a number of posts on Citroen sites. There have been suggestions to widen the tappet gaps to inlet 0.02mm and exhaust 0.025mm which is set currently. Unsure whether this is correct though, suggestions would be appreciated?

The carb angles are 30 degrees. I am awaiting some manifolds to be TIG welded which will lessen the angle to 5 degrees although the manifold will be longer. They will be easier to balance and access.
Following refusal to start when hot I have removed the plugs to find them sooted up. This is following setup with colortune? Any assistance will be greatly appreciated - Steve

[howardjs]

Hi, FWIW,
I have a very similar set up, DG ignition unit (similar to 123). Electric pump and filter king regulator. Dellorto PHBH carbs, a lightweight mini alternator. 14.2 volt output which is normal no load voltage.

I don't understand why ECAS are telling you that bougicord leads are CRITICAL! Does 123 have such a specific HT lead spec?

Talk to the Green Spark Pug Co, gsparkplug.com
Mine is fitted with 7mm tinned copper core HT leads with GKN right angle resistor plugs and no probs.

Tappets are 10thou 6-8 is the recommended gap but if you have no air cooling fan and ducting the engine will run hotter.

When I was setting all this up, a long time ago now, I also experienced a misfire at high revs. The fuel line was being interrupted by a dead insect inside the cheap Chinese regulator. so changed to a Filter King. The pressure was a bit low at first resulting in again an occasional misfire, After gradually increasing the pressure all was good.

Also I did experience popping and backfiring. this was caused by the Dellortos having too small an idle jet. I increased to a larger size now OK.

My plugs are a bit sooty until it's been on a longish run, then OK. Using a Colortune will never give the same result from both plugs. Maybe because the current flow is going the "wrong" way through one plug (double ended coil, lost spark system).

Keep going, when it's right it will keep going through thick and thin...

Howard

[Sinbad]

Hi Howard - Cheers for your response and help. I will contact the Green Spark company. My Pembleton has no fan and cooling cowling fitted. As far as the plug leads ECAS suggest Bougicord are the best and most suited. But now I know your setup works ok I will go with them. Did you get the leads assembled or built them yourself ? Thanks again you have been a great help. - Steve

[Sinbad]

Hi Howard - what fuel are you using ordinary unleaded (E10) or super unleaded (E5) regards Steve

[howardjs]

Hi Steve, The Green Spark Plug Co. are not far from me so went to their place after one of my leads shorted out. They recommended the tinned copper. I just bought a length and 2 GKN plug caps. The caps come with rubber seals and just screw on to the end on the HT cable. The other end is just crimped onto the coil connectors. Because it is copper core it can be stripped just like any other cable.

I'm using E5 unless I'm desperate and the garage only has E10.

Actually that's another thing to watch. Another of the possible causes of my fuel starvation was rubber fuel pipe that had become restricted internally. No evidence on the outside but the 1/4" bore had reduced to about 3mm!

Howard

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[CSC1540]

Hi Guys I have a couple of cables that go near the manifold , I cover them with an oven shelf guard , have a look at 232645900520 on ebay and you will get the idea.

Regards Ray

[Sinbad]

Thanks again Guys for assistance.
pm

Hi Guys - I thought you might be interested I am going through everything methodically. My present fuel system has a Facet posiflow 60104 pump sited adjacent to and in front of the tank (at the bottom). There is an in-tank strainer so I have removed the pump strainer at the suction (very recently). It sucks through 6mm copper pipe and fuel hose. The outlet is 6mm copper and hose which flows to a fuel filter king. The next inline is a gauge, the line then splits to feed the Dellortos (PHBH 28).
When the pump runs a pressure of 2.3psi shows on the gauge. I have attempted to adjust the fuel king but the pressure stays at 2.3psi. I have stripped the fuel king and it looks ok.
Then I placed a 8mm hose bypassing the Fuel King. I blocked off the fuel hose which feed each of carburettors. I started the pump which pumped to 2.3psi. (Closed system).
I unblocked the hose to the furthest carb and lead it to a 5 litre petrol can to check the flow rate of the pump. I calculated the flow rate to approx 13 US gallons per hour. The pump specification indicates a flow rate of 26 US gallons per hour. The pump specification also indicates a pressure range of 1.5psi to 4psi. The thing is the pump is still in range of the requirements of the engine however I am wondering whether when considering connection to the 2 carbs etc perhaps this could be my problem. Your thoughts would be appreciated?? Anyone using Hardi fuel pumps? They are German and work on the same principal and pressure as SU pumps. Cheers Steve