The Triumph Dolomite Club - Discussion Forum

The Sprint is finally idling very sweetly but once I put the engine under load, it starts chugging, as if a plug has gone dead. Idling back it's ok but won't take up speed.

ideas?

It's due for a head recondition and timing chain replacement.

Oil in dashpots or lead or plug breaking down? Insufficient points gap or duff condensor....you name it, it could be loads of things.

Change one thing at a time....

Jonners

Fuel starvation

Paul

Flyfisherman wrote: ↑Mon Jun 12, 2017 7:49 pm Fuel starvation

Paul

hmm - that's interesting.

Mario

Check the bottom of the float bowls for dirt / debris etc - this could reduce the quantity of fuel going to the jets, whilst on tick over its fine but when more fuel is requires it could be resticting the flow - assuming you have SU carbs.

Paul

Flyfisherman wrote: ↑Tue Jun 13, 2017 5:17 pm Mario

Check the bottom of the float bowls for dirt / debris etc - this could reduce the quantity of fuel going to the jets, whilst on tick over its fine but when more fuel is requires it could be resticting the flow - assuming you have SU carbs.

Paul

Could this be the reason? The SU manual says that the gap should be 0.125 but it's more like 3/8 inches. The other one is only slighter better. No adjustment is possible so it seems that the wrong valve/float has been fitted.

Problem solved - PO fitted a washer which, once removed, let the float higher in the chamber. Will check whether this makes a difference to the 'chugging'

That angle is not good of your float. The base has to be level or a tiny bit going up. I do sand a fiber washer to size to have the correct angle. Also the floatneedles come in sizes. A sprint does need the larger size. There are many parts in su's that look identical but are not and are easily mixed up.

Jeroen

Had the Sprint sent to a mechanic friend as I could not solve the severe tapping issue that it had. Within 30 minutes he phoned and said that problem solved - a shim had fallen out and led to the tapping noise! How the hell could that happen (the shim falling out I mean)? It never occurred to me to have a look around the cylinder head.