Traveller misfire.

[Kittyhawk]

Our recently acquired Traveller was running really badly and misfiring. A compression test revealed that one cylinder had no compression, so I took the head off and a valve had burnt out. I had new valves and guides fitted, together with a skim and new valve seats.I rebuilt the carb and fuel pump and replaced the vacuum advance, which was not working. She fired up first turn of the key and seemed to run OK. I took her out for a test run and she was 'kangarooing and showing what I took to be fuel starvation, eventually stopping completely. I checked the float chamber and there was fuel in there. managed to get her going and limped home. I have done a flow check on the pump and blown through the float chamber to jet pipe and all is ok. Did a compression test and have rechecked static timing, points and plugs. She starts first time, but as soon as I increase rpm, she is missing and stuttering.

All suggestions welcome.

1968 Traveller
Almond Green

[beero]

Open the bonnet and have a look with the engine running in complete darkness and see if there are any stray sparks anywhere.

[Lurch]

I'd suspect electrical.
Just for starters, being as it's nasty rainy season, give the ht leads a spray with wd40 or damp start type stuff, I had a motor once that was fine if you did and simply didn't want to know if you didn't !
I was too mean to buy a new set of ht leads !

[Trickydicky]

As you have rebuilt the carb, have you set the mixture correctly?

[Kittyhawk]

Thanks for the replies

I set the mixture 2 turns down for starters, then adjusted as per the manual, lifting the piston and checking the result. I assume this should be done with a warm engine, which is difficult at present. The plugs were a bit sooty when removed. Points are new and I have ordered new rotor arm and condensor just to eliminate those.

[mogbob]

" With engine warm ? " Yes.
It's also a good idea to blip the throttle every now an again during the tuning process to clear unburnt fuel.
Bob

[dalebrignall]

just make sure you have ordered a decent qualiaty condencer ie from distributer doctor , accuspark, there are lots of cheap and nasty ones from china on the market now they either work , or dont .anything marked lucas is the same now all not brittish made . what oil did you pit in the carb should be thin damper oil .

[dalebrignall]

also starting point for mixture is wind the mixture nut right up to the top then go down 12 flats thats the factory setting and re tune from there , a dunstones colour tune is a good aid to getting the mixture right .

[mogbob]

Kittyhawk said he had turned down the mixture "

2 turns down for starters "

.
Two turns of a six sided nut = 12 flats. So you're both reading from the same page.
Bob

[simmitc]

See http://www.mmoc.org.uk/viewtopic.php?f= ... it=misfire I reckon it covers everything you could ever want to know about a misfire. It was on a Traveller too!

[Kittyhawk]

I have a timing light, but am at a loss to see how it's possible to view the timing marks, as they are below the crankshaft pulley

[dalebrignall]

there should be a small notch on the pully put dome correction fluid on it and you should see it better

[Declan_Burns]

Kittyhawk,
Make up something like this so you can set the timing from the engine bay. If you want I can provide a drawing showing the graduations and brackets in 1:1 scale. You can have a sticker made a printing shop or DIY it.
Regards
Declan[frame][/frame]

[Kittyhawk]

Thanks Declan, that would be helpful.
There is already a white paint spot on the pulley on the appropriate place, my point was that I can't see below the pulley and behind the radiator!

I tried flicking the points open with ignition on and got a spark, which shouldn't happen, so fitted a new condensor and red rotor arm from Accuspark, cleaned all the connections and sprayed all the HT leads with WD40. She fired up first time and seems not to be running at all badly. Reset the mixture again, but couldn't go out for a road test due to flooded roads. I will do that at earliest opportunity and report back.

Thanks again for all the advice

[Declan_Burns]

Kittyhawk,
If you use my set-up you will have to file a new notch in the pulley at TDC. Put a dab of paint on it and paint over the old notch.
Regards
Declan

[simmitc]

I can't see below the pulley and behind the radiator

You can from underneath the car. Not ideal, but raise the car and support it safely, then crawl under just enough to see what you need.