Club Triumph

When I refurbed the carbs I fitted new spindles and butterflies, the butterflies closed fully.
With both tickover screws fully wound what would cause the tickover to stay at 11-1200 ?
The mixture is about right and the timing is set 12 before, I've fitted one of Radders spare dizzy until funds allow a replacment, so that's all ok.
Not sure what else to check 😳
Throttle cable is probably too loose so it's not being held high by the cable

Sounds like you could have an air leak Dave

Yes, servo hose, inlet to head gasket, carb to inlet gasket, vacuum advance hose...

Try spraying WD40 across the suspect areas with the engine running. When you get to the right area, the revs will drop and the exhaust will go white.

Don't get too liberal in case it flashes.

Did you fit the butterflies the right way round according the angled edges ?

Also check that the butterflies are aligned properly and fully sealing when closed. Sadly, the only way to be sure is take the carbs off and hold them up to the light. If you can see even the faintest light around the butterfly slacken off the screws and you should see them snap into place, then re-tighten.

I've had to strip and re-assemble brand new carbs for people before ....

Make sure the engine breather, dipstick and oil, filler are sealing
you could  be sucking excess breather air in the carb vent tubes .

pete

Butterflies defiantly fitted correctly.
I'll have a spray about when I get to work in the morning as see if there's an air leak

Hello Dave,

the butterflies are my favourite also,they can be fiddly to get absolutely right.  Block off the carburettor intake (one at a time)and see what happens to the engine speed?

Alec

When I refurbed the carbs on my herald I did fit them the wrong way round,this time I made sure I didn't.
There's a chamfered edge to create a good seal and once the new spindles were fitted I slid the butterflies into place and held the carb bodies up to the light to ensure a good seal,I then fitted the grub screws and re checked them.
I can't see it being wrongly installed butterflies but i will if all else fails remove the carbs to check again.
Once a get to work in the morning I'll spray some wd40 about and see if anything happens

Wd 40 sprayed everywhere including servo hose :- nothing changed.
So carbs off at the weekend, but I know I double checked them when I re built them

what were you trying to test using WD40?

If you are looking for an engine reaction would not start help be better?

AndyF

Errr I think Dave wants it to Start,

Not  Not start,
where can one buy this Not Start  stuff Andy,(think)(think)(whistle)(whistle)

Dave, iff they not seated perfectly, or even  ona slant,!!
PI throtttle can be in, but they slanted, so no seal as good
they got a line across too, so can see if no level,

Yours got same !!!

IF after modding and still leky, then slacken screws off on disc, and wid care full waks with a ammer, and a  softish something,
tap the Tops of the discs to sealit by eliminating any high spots,
either ont carb body, or throttle disc.

then when ye tinks it OK, smaer aroond the disc sides
carb body wid grease or Coppa slip, this will really seal it

like most things wid a disc, they work best wid crud build up on em,
as this seals in all the low spots.

thats why folk wid PIs get awfull idle, as they cleaned of all the sheite.

M

Nigel started with no choke this evening so I'm wondering if it's still just too rich.
The governors dad had a play, I'm just about to go out and take the carb tops off and re set the mixture as he just screwed about with the mixtures and now I've no idea what it's set at 🙄
I'll set it one flat leaner than I had it and see what happens

Before you strip too much down do plug the breather inlets
To eliminate any chance you have excess breathing allowing  air in behind the throttle plates

OR   if you remove the oil filler  cap and there is no speed up your sealed breathing.......isnt

pete

My oil filler cap is a crap fit,could it be that simple !
I've just set the mixture at :- 1 full turn and 2 flats down,the car drives fine but the tickover is still a tad high.
I'm wondering if the fuel level in the float bowls is too high as I can see fuel in the front carb jet tube, it's not as high in the back carb.
How high should the fuel be in the bowl.
How do you set the fuel height I know you put washers under the bowl needles to adjust it,there must be a "gap" you measure somewhere

the fuel is generally a few mm below the top of the jet

stromberg  top of float to base is normally 18mm and su 3mm between float and top cover  or there abouts

but  Please  do the cap fit first, it really can be that simple  

Pete

Floats set about right, but they are the same

Fuel level dosnt seem to high to me, again both bowls are at the same level


Oil filler cap has been adjusted to be a better fit, new rocker cover going on at the weekend with a nice new cap
Pulled choke started car then pushed choke in and drove off fine when I left work tonight,so still rich
I've now set mixture at 1 full turn down that's up 2 flats from what it was today, I'll see what happens in the morning.
I just started the car and tickover is about 700 ish so with luck I may have found the fuel level in the carbs or it could just be the engine has cooled 😒
I'll find out in the morn

Float heights dont have great effect on idle speeds  

its best to do one thing at a time then you dont have to guess which was the culprit

i had troubles with over filling and despite new valves it was a small wear groove in the float
which upset the needle valve closure   new floats solved much frustration and head banging and they didnt look that bad.

pete

Pete
Once again leaving work tonight:- pulled choke started engine,pushed choke in and drove off fine.
Once home I've leaned it off one more flat,that's now 1 flat less than 1 full turn down from a level bridge,if I end up at a level bridge setting and it's still driving ok then I'll pop a washer under the float valve to lower the fuel level, then I'll pop the carbs off at the weekend and check the butterflies,but I know there ok but I will re check.
I'll also check all manifold nuts are tight but again I'd say there all tight but I'll check.
I will get it sorted.

Are all HS floats the same as I've got a spare set of HS4's carbs down the shed that I could rob !

just a thought outside the box  the new jets are the right size dia hole ???         2.5 hs6 is  std  0.1"  but theres also 0.125"  around

Pete

No idea Pete, I got the needles from witor.
Carbs are from a dolly sprint if that makes any difference

Latest :-
If you look at the pictures of the fuel level in the bowls I would say it's about right but when the tops go on it must raise the level so I fitted a washer under the valve to lower it. If you look at the picture of the floats on the earlier post, by fitting the washer the floats now sit level and not down at an angle. Mixture now set at 1 full turn down from level and it still drives lovely so not sure I've lowered it enough, I might have to obtain new floats.  It's just still got a lumpy/fast tickover.

Managed to get a couple of flats on all inlet and exhaust manifold nuts, they were tight but now tighter.
I've replaced the brake servo hose as it looked a bit split at the manifold end the splits weren't through but I've renewed it. However the rubber gromit that the one way valve seats on the servo in is split although it seems air tight as the valve goes in beyond the split. I'll try and get a new one.

I've checked the butterflies as best I can without removing the carbs, Pistons up shining a torch and looking down at them,they both look good.

Both carbs are balanced and operating together and the timing is 12 degrees before with no pinking.
When I turn the ignition off there is a very slight run on for a second or two.

Not sure what else to look at 😒

What fuel do you run it on?
my 2.5 runs on with 95 unleaded but fine on V-Power.
S