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Triple carb setup too rich? How to adjust?

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B

BJ7archaeologist

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Fellow Healeyites,
I have a triple carb setup on my 63 BJ7. It consists of three manifolds bored out to 1 3/4 inches with 3 HS6 carbs.
I have BC standard needles and red 4.5oz spings as recommended by www.ahc-midlands.org.uk for their triple carb modifications. The choke is off but my plugs keep fowling. I have NGK BPR5EGP plugs. Maybe they are too cold???? I also have a facet fuel pump with no in-line regulator. Maybe I need a regulator. I adjusted the chokes repeatedly to no avail. Now I think that I will double check the float levels. Could the float levels be too high? Also, with these mods what should the gap be for the needle and seat assembly. Thanks!
 
Take the Dashpots off and with the ignition turned on look to see if petrol is overflowing from the main jets. If it is and the HS6 carbs are the ones with nylon floats you need to take off the lids, invert them and make sure the clearance between the ridge on the lid and the nylon part of the float is 1/8".

If the gap is correct and the flooding continues, replace the needle assemblies with these

https://www.moss-europe.co.uk/Shop/ViewProducts.aspx?PlateIndexID=18415

You can check what the fuel pressure should be from the www.burlen.co.uk site and also the relationship between needles.

The manufacturers all used to set the cars up with the main jets 35-38 thou below the jet bridge.

I hope this is some use.

Ash
 
When you say that the plugs are fouling, are you starting to lose spark in the cylinders? IE. dropping down to 5 then 4 etc. My car burns oil so you can't get worse fouling than that. With cool plugs ( some idiot guided me to a new set ) the cylinders just fell away one by one. Replaced them with a new set after finding out all about hot and cool plugs and the problem disappeared.

:cheers:

Bob
 
I think that I fixed it today. I removed the dashpots as recommended, turned the key and wittnesses a gushing spout of gasoline shoot 2 feet into the air from #1 carb. I installed a pressure regulator, new float needle on #1 carb and a different float bowl lid on #1. I think that it was the float bowl lid. The one I had on had three brass fittings. One overflow, one inlet, one outlet. It was not supposed to have the overflow. The one I installed did not have an overflow. Seems to work fine now. We will see if my plugs foul but I doubt it. Thanks!
 
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