Bedford MW engine - help!

[matchlesswdg3]

My MW's 28hp engine has developed what sounds like a horrible misfire during its last run out. There is no blue smoke but it is very lumpy running and vibratory.......I hope I have ruled out big end problems as at the tailpipe, you can hear the stutter in the firing. I have not had the MW long having bought it restored but not used since restoration so was expecting commissioning issues. I have found some minor bodges around the engine that need fixing (one being a bodged distributor cap clip - though that does not seem to be the misfire source - but who would replace spring steel with feeble ally???) - and rocker box gasket seems to comprise gasket goo only. I have just bought a compression tester and having read an article about similar symptoms on a Dodge, I am hoping it is a duff cylinder head gasket allowing gases to escape via adjacent pistons. Or it is an exhaust valve problem - not unknown on these engines, I understand. Hopefully the compression results will throw some light on this. Anyhow, if anyone lives near Ashford, Kent, I would be grateful if they could lend an ear and cast an expert eye over the lump (if it ever stops raining - the MW lives outside under tarps, alas) before I start hurling spanners. Any other words of wisdom and encouragement (?) welcomed!! Ferg

[rampant rivet]

Hello fellow Mw owner I am by no means an expert on these things but maybe check plugs and leads then compression to help identify problem cylinder, could be just a duff plug or lead if you are lucky, then head or gasket or pos valves not seating, just a thought.

 

RR.

[GeePig]

Have you checked the ignition timing? Secondly, have you taken the spark plugs out and checked them for colour/oil? That should give us some clue as to what may be happening.

 

Sadly, I left Ashford and Caffyns years ago...

 

trevor

[Tony B]

One quick trick. Wilst engine is running take each plug off independently, when engine note dosen't change, that's the duff one. From the sound of it, start with the easy and cheap route and check electrics. Dis cap, plugs . leads , condenser and points first. Banging an old drum. Investment is an electronic ignition is worth making.

[Richard Farrant]

hi Ferg,

I am at Ashford and a Bedford owner, just sent you a PM.

 

cheers Richard

[Degsy]

Ferg, trust Richard, he will sort you out.:thumbsup:

[MWMike]

I agree with the comments re checking and renewing electrics, I had the same problems with my MW (which ironically I bought from Ashford 3 years ago!) with a couple of very fluffy cylinders. In addition to changing plugs and points, I found that she "foamed from the nose" ( a fine foamy water spray from the rad cap) which seemed to be causing some cylinder head overheating on cylinders 5 and 6 which were misfiring- this I cured by flushing out the block and head, including the difficult drain tap at the back of the block accessed from the little panel in the passenger footwell. I had to pressure wash the engine through this valve ( I took the valve off and it fell to bits in my hand as the carbon steel spring had rotted!) to get all of the rusty gunge out - it was solid, and then clean out the system using some radcleaner stuff.

 

This fixed the "foaming at the nose" issue and also seemed to help the lumpiness of the engine and she stopped misfiring on 5 and 6, so maybe it was contributing to a hotter spark plug or some plug oiling phenomena?? ....or of course it could have just been the electrics!

 

mike

[Tony B]

Mike , your description is quite vivid! I'm off for a a Rabies shot.