Howdy, y'all. Had some engine issues with the Acad since it went back on the road about 4 months ago and I've exhausted my limited knowledge in these matters. Hoping people can field some suggestions for avenues to investigate....

Symptoms (all when cold): Engine generally crap; idles so low it cuts out, hesitates when throttle depressed; suddenly loses power for a second or two for no apparent reason; wipers slow right down when stopped at lights (i.e. idle); occasional running-on when ignition switched off; relatively frequent misfire for first few minutes.

Known problems: Exhaust blowing at cross-box/swan neck joint.

Work done (no improvement): Points/condenser replaced; timing done; spark plugs replaced; ht leads replaced; new coil; fuel filter replaced.

All the problems rectify themselves after a few miles once the engine has warmed up a bit, and after that its a flying machine - the gps claimed 83 the other night (I have to trust the gps as my speedo light has never worked lol).

Any ideas?

Valve clearances might be a start. Tried a compression test?

Not yet - was considering buying a compression gauge a few months back - might have another look at prices...

I should add that its a recently refurb'd 2cv engine/gbox in it, as the originals were totally gubbed. i say recently - about 6 years ago, but its only done maybe 6000 miles in that time tops due to being off the road more than not.

Clean the carb

That had came to mind the other day, actually - the rubber hose from the air filter had sorta disintigrated before i replaced it - i had wondered if a wee crumb of rubber had fell down into the carb somehow.

I'm alright with engines to a degree, but I'always think of carbs as fragile and needing to be really precisely set so i've never touched them. Wouldn't taking it apart to clean it mess that all up?

as dave said a good carb clean/service
it sounds like the carb accelerator pumps not working and maybye causing the dead spot

,
Do you know you there is a choke????? Use it when engine is cold, with choke pulled it has to idle even at higher rpm then a warm engine without choke????

again pull the choke about 3/4 of an inch and it must pick up nicely.....


Something wrong with your wiring?? Wipers shouldn't slow down (much)... when idle.
Check all wiring to and from your battery, shake them a little and check if every wire is connected solid...... check also the wires going to your alternator......
It can also be the ignition switch, take it apart and claen it, sand the contacts and check if the wires goingn to the ignition are connected solid....

Haha yeah, I know about the choke, but its always a good idea to ask the obvious questions! I've been around a-series since I was about ten years old and its amazing some of the things you suddenly realise you didn't know :p

I should have said in the OP that these problems are with the choke in use. Trying to run it without just makes it cut out the second you lift the clutch, and thats if you're lucky!!

Dirty idle jet - don't be too phased about carbs being fragile - they are quite resilient. Try cleaning the brass jet at the front of the carb under the point where the fuel line goes in and above the idle mixture screw......

Another thing to do is to check if you have an air leak anywhere - spray wd40 or brake cleaner, whilst the engine s running, around the mounting area for the carb, where the insulating block is above the manifold, and also where the inlet manifolds attach to the cylinder heads - any air leak will result in the engine revs dropping.