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EEtinkerer
01-08-2004, 12:10 AM
OK Everyone,

I'm back and this time with no more good news as to the running state of my TR6 with the triple 40DCOE webers. I took the jets out last night and blew them all out with the compressor to make sure they were not blocked. I also took the needle valves out and blew out the seat with air as well as the little filters above. Putting my mouth to the fuel inlet, I tested the needle valve and it indeed closes and opens with the floats. The engine still runs poorly after changing all the basic ignition parts (points condenser cap etc) and rechecking base timing with a test light as suggested in some old triumph books.

I have another question about a problem that seems like it could be causing many of my headaches. All three of the carbs (all six barrels that is) pour raw gas directly out into the air cleaner assembly. I took the air cleaner off to look while I tune and the gas just rolls out the fronts of the carbs and onto the fender. This seems very strange. i have checked and adjusted the needle valves on all the carbs and no adjustment level seems to stop this problem. I've checked the alignment of all the throttle plates across the carbs to make sure they are all in alignment and they seem to be all zero-ed plus 1/2 turn on the throttle screw. All idle mixture screws are set to 3/4 turn. I tried as some suggested with new gas and the car still doesnt run so I think that this spillage problem is a cause (it's at least not a desirable or SAFE thing to have.) Any of you with weber knowledge would be greatly appreciated! Thanks again!! One last question about the running problems. The rough running seems to disappear when the engine reaches 3000rpms which seems to be the limit of the idle circuit so it sounds like there is a problem in the idle/progression circuit. If that information helps diagnose the gas spillage OR the running problem, I will be most grateful!

A.J.

Dave Russell
01-08-2004, 12:43 AM
AJ,
If you're sure that the needles & seats are perfect & are set correctly, I would check the fuel pressure. If it is much over 3 psi the carbs may flood. If the pressure is too high you need to put a pressure regulator in.

If it is only flooding when the engine is hot, the fuel may be boiling in the float bowls. There should be heat insulator spacers between carbs & manifolds.
D

EEtinkerer
01-08-2004, 01:04 AM
I have an inline fuel pressure gauge that reads about 3-4 psi. The carbs flood all the time regardless of rpm. I can't get the engine to run well enough to warm it up. It has other problems that I am trying to sort out that are preventing me from running it for any long period of time. The heat spacers are in place and I even replaced all the O-rings on them (lubed lightly with heavy grease to ensure seal) becuase I was worried about a vacuum leak.

Dave Russell
01-08-2004, 01:54 AM
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by EEtinkerer:
I have an inline fuel pressure gauge that reads about 3-4 psi<hr></blockquote>
This may be too high. Try lowering the pressure & see if the flooding stops.

You shouldn't be running choke sizes any larger than 27-28mm for street use.

Do you have brass or plastic floats & what is the float level setting?
D

[ 01-07-2004: Message edited by: Dave Russell ]</p>

EEtinkerer
01-08-2004, 02:27 PM
I have the plastic floats and I set the floats to close when they are parallel to the mounting surface. I know they are supposed to be set with a dowel rod but that method seemed a bit confusing. I also didn't have a dowel the 'proper' size. Isn't the dowel rod method for the brass floats and not the plastic?

Dave Russell
01-08-2004, 05:24 PM
AJ,
The level for the plastic floats should be 12.5mm from the gasket surface, with gasket installed, to the float surface at it's extreme tip. Make sure that the ball spring is not compressed. 12.5mm is very close to 1/2 inch & a 1/2 inch drill bit should just fit between the float tip & the gasketed surface. The dowel rod is for both types.

An additional check is to remove the lid & measure the actual fuel level from fuel to the top of upper face of the fuel chamber. This measurment should be 29 +/- .5mm (1.14" +/- .020". This will show if the balls & seats are actually sealing & shutting off at the correct levels.

Good luck,
D