Practically Classics Forum

Right, long story short, Triumph 2500 PI, but now on twin SUs.

Starts, runs fine, drives OK no bother. Can go off for a nice drive, then it will just die, cuts out like its run out of petrol. Glass fuel pump on side of block has a healthy level in, but the plastic in line filter just before the carb can appear to be empty. It will just crank over as normal, no hint of starting. Leave it a few minutes it will start.

PO has replaced the points and condenser with an electronic set, Pertronix I think, 60 odd quids worth, so not the cheapies off evilbay. I have replaced the coil as it looked to be the original, and of course, Triumph use a ballast resisted set up, this has been bypassed and its running the full 12v, it's had a new cap, but rotor hasn't been replaced. I have heard of some being temperamental, and the contacts breaking when they get hot and expand, but before I order a replacement, has any one else any other ideas?

I set the carbs up last week, and its running much sweeter, but this cutting out is beginning to **** me off!

Fuel evap?

It could be Mal, the fuel pipe (metal) runs from the pump, along side the block, up over the top of engine, right next to stat housing, before going into the final filter before the carbs.

One thought I have had is replacing the mechanical pump on the block with an SU pump or similar to try and overcome that problem.

This is how it repays you for giving it a wash and polish...

Is the breather to the fuel tank blocked? That could stop the pump having enough oomph to get fuel all the way to the carbs.

Hmm that's a thought. I'm not sure how far the conversion went when they swapped it to carbs, I wonder if they kept the PI tank and just blanked off the other pipes? I'll pop the cap off next time it plays up to check.

It has been mentioned black rotor arms regularly play up, I thought it was red when I looked first off, but it is a black one, I think I'll throw a new red one on for the sake of it anyways.

The quality of rotor arms has really gone to pot recently. "genuine" lucas arms seem to be made of tin foil and burn out really quickly. I have taken to using halfords ones as they have a decent thick piece of metal on them and don't require changing with every service.

For the sake of a few quid I'll get a new rotor, probably go to someone like the Distributor Doctor, his red ones come recommended.

It's one of those annoying faults that has no rhyme or reason to it.

I had this issue on my Scimtar GTE and it turned out to be the ignition coil breaking down when it got warm under the bonnet. Like you, Id leave it 10 mins and it would start again. Worth a look at least?

Just a thought, have you tried it without the plastic inline filter, and if its one of the normal cheap universal ones is it the right way round ?

Could it be something as daft as the carbs icing up? My old Minx was a begger for that and I only discovered that I was pointing the air filter inlet the wrong way after I sold it!

I used to have probelms with pancake air filters and, when I fitted one on my Maxi, I modified the original air filter housing so I could keep the "summer/Winter" setting - it cured the problem straight away!