The Triumph 2000 / 2500 / 2·5 Register Forum

Or has something happened to the front pulley allowing the timing marks to be moving independently to the crank?

Hello Robin,

this is bizarre, normally the only thing that requires a variation of timing is mixture, but I can't believe that it would weaken to the extent of needing 36 degrees advance and still run 'sweetly'.
When I have such a problem I like to go back to basics and do a full engine set up to know where I am.
Check the tappets gap and while you are doing that check the cam timing. The quickest way to check that is to set the crank to TDC firing on number one cylinder, now rotate the engine back and fro about TDC and number eleven and number twelve valves should just be opening and closing. Have a look at the plugs to see what colour they are, if they are very white you are running too weak.
Initially I wondered if the dog was slipping on the distributor shaft but that cannot be the case if the distributor is physically moved and the timing moves with it. Nor can it be the front damper, similarly because you are physically moving the distributor to regain correct (ish) running.

Alec

Thanks Alec

It is still arcing in the cap, so i'm wondering if its a fault rotor arm too.

As you say, I think i'm going to start a fresh and get it running smoothly and properly on points and condensor if I can and go from there.

Regards

Robin

Well, I'm so glad I started with the basics, as it looks like a faulty rotor arm was the culprit !

It's idling and revving nicely, not got the confidence to take it out just yet tho, few more checks first !

So, after a few more checks, I am pleased to report the matter is almost resolved !

However, it wasn't just the rotor arm, the reason the timing was all over the place was that the distributor shaft has become detached from the bushing for all the bob weights and the shaft is rocking side to side.

I'm surprised it started at all to be honest, so a new distributor is in order !

Hello Robin,

where are you getting your distributor from? Some of the E-Bay distributors are sold as 'will fit such and such' Yes they will but probably are not the correct specification?

Alec

Hi Alec

I haven't found one yet, I'm less worried about now I know what it is, Rimmers can't help other than to try and rebuild the existing one but I think it'll be too far gone.

I might try a drop in electronic replacement just to see if it's any good, they are only £70, whilst I look out a proper original one, assuming one exists.

Any sources you know that I can try ?

R

Distrubutor Doctor should do?

Hello Robin,

I second Bill's recommendation, I had my distributor rebuilt by him, the only downside is the time required. In the meantime, if you want a replacement try Winns and Co for a second hand unit?
Alec