HS6 rebuild kit/ needle option

[Triumphtastic]

(Possibly clutching at straws but....) I can't remember but has the exhaust system been changed? I wondered if the baffles had broken up inside the silencers and could be causing such a problem as I recall this happening on another low mileage car which had been laid up.

[Forkie]

Ah yes - how could i forget - so that is the one major ' engine' change since being off the road - the original system was a miss match of bits so had to be cut off. It now wears a full C.W. stainless steel system, from the manifold right through, with his recommended semi sport back box. I had often wondered could it be that, as that is the major change - but why would i be the only one for that system to lose my power

[Mike Stevens]

I see you've checked the fuel pressure, but have you managed to check the fuel flow? Not easy I know I'd have to check the flow figures, but I think they'll be in the main workshop manual. I'll have to find mine as we've just had a refit of our living room and nothing is now where it was! I reckon you could get the float chambers full, switch it off and re-route the fuel pipe to a container and run the engine for long enough to get an idea of volume against time.

Given the choice, always run it slightly rich rather than weak, that should help save the exhaust valves!

Cheers,
Mike.

[Forkie]

Ok so took a bit of communication time but got hold of the chap that came round last year to help me diagnose my issue. He did check pressure and flow and all was inside the values.

So to recap - between 2008 ( went off road ) and 2022 ( back on road ) - these were the things that were changed - NOT including the underpinnings) :
Exhaust - from a makeshift steel , to a S.S. full CW unit.
Wheels /tyres - from original alloys to minilights - can rule this out
as was the same at the start running on the originals
Fuel pump - my original one had stopped working - so had a N.O.S. ready - so swapped over - initial fuel leakage but then settled down
That N.O.S. pump has since been tested - rated ok.
Diff - i removed, sent entire unit to the local ( then) trans place for inspection - was deemed fine. Collect and refit.
It has been suggested this eve was i handed back the wrong ratio diff?
As there is no missfiring/ stuttering etc ehen she backs off, it cant be an engine issue. An electric fuel pump has been suggested - any thoughts on that?

[Alec]

Hello Forkie,

a long time ago my 2000 would run but was very flat. Despite me checking and double checking I could find no fault. In desperation I wound on a relatively large amount of advance and that was the answer. Whether for some reason the mark on the damper was wrong but adequate advance cured my lack of power. Do check that the balance mechanism in the distributor is free, you should be able to turn the rotor arm backwards for a few degrees and it should return.

Alec

[Forkie]

Hi Alec yes i think you suggested that a while back and it was free. This chap is wondering if the N.O.S. fuel pump , although showing fine values at idle, could it be that on the move it cannot cope for whatever reason - he suggesting temporarily trying an electric fuel pump , just to rule it out? I would of thought i would have missing/ spluttering though if fuel supply is low ?
Other than that he thinks the only other thing is the wrong diff fitted... which seems unlikely to me. The chances of the transmission place where it went for checks 10 years ago having TWO T 2000 diffs in,at the same time, of different ratios must be extremely slim....
I have not yet took it back out since my second attempt at fuel mixture settings however so i will try it at the weekend. Im hoping for a miracle cure !
Will will check the timing etc as well just to rule it out.

[johnnydog]

I can't see it being the diff - assuming we are talking about your 2500S, the ratio should be 3.45:1 (both auto and manual) - if it had been inadvertantly swapped for a 3.7 or 4.1, then I think you would have noticied. It would be revving excessively especially with a 4.1
To put that out of the equation, it is easy to check what diff you have by jacking the rear of the car up and counting the number of propshaft rotations relative to one road wheel rotation. If you mark the prop with some chalk or tape, and using tape on the inside edge of the tyre as a marker, 3 1/2 turns of the propshaft should be more or less one full rotation of the road wheel for a 3.45 diff. If it's nearer to 3 3/4 rotations, then it probably is a 3.7, and if nearer to 4 rotations, then it's likely to be a 4.1 (both of which I think are unlikely).
You could also disconnect a drive shaft at one flange and check the paint marking on the nut of output flange of the diff - a 3.45 should have red markings. But probably easier just to count the rotations!

[Forkie]

Thanks for that explanation - that was going to be my next question this evening - i knew i had read something like that somewhere, sometime ago - so thats great , as i really need to settle my mind on that but as i said above the chances of TWO T 2000 diffs being in that same work shop at the same time, and of being differing ratios, in 2015 , have to be slimmer than winning the lottery .
I think this chap is clutching at the same straw as the rest of us as he was confident when he was round last year that it was running fine but with autobox issues which have now been addressed so he was surprised to learn she is just the same after all the work ,new parts and tests done. Its hard to explain how it behaves but as soon as an incline appears its like a parachute gets thrown out - the power just drops off but there is no coughing/spluttering/missfiring etc - you just feel it back off. Along the flat or dual carriage way scenario it bottoms out at 56 ( on the lads' phone speed app) and just does not sound right at all, not smooth anyway.

[Forkie]

Food for thought. Just had another chat with this guy i am in contact with, he suggested the electric fuel pump as a 'temporary' trial. I just rang him to say i have a Powertune pump that i purchased a while back from C.W. as a back up. I'm not keen as it looks ugly compared to the original glass domed unit.
Anyhow - my original pump stopped working during it's lay up, so i swapped it for an original N.O.S. that i had picked up over the years. Once fitted and i started the car up it was leaking fuel everywhere But it did settle down, sealed itself, and has been leak free eversince.This is the the fuel pump that is currently fitted to the car, and passed all its 'tests' for fuel flow and pressure......
But thats all done in the garage, not under load. Could there be a fault with that ' unknown ' age fuel pump, that doesn't behave as required , under load.....so im thinking remove the N.O.S. pump and try it with the Powertune ugly lump, just to see what i get....

[Mike Stevens]

I agree with Johnnydog. As far as I know there were only 3 different ratios in that diff design, 4.11, 3.7 and 3.45. The lack of power you describe would suggest a higher than normal gearing, I.E. a lower ratio than 3.45!

Ignition advance is a possibility as mentioned by Alec. Wind on more advance, the worse that can happen is some pinking (probably!)

Give the electric pump a try as long as you can fit it in there safely - you don't have to leave it there as you could always refurb the original later if that was the issue.

Leaking brake servo system, which could upset the mixture? Mind you it'd have to be one hell of a leak to make a significant difference with the engine on full chat!

Cheers,
Mike.