Author Topic: EW running weak  (Read 12677 times)

0 Members and 1 Guest are viewing this topic.

Offline tck

  • Senior Member
  • ***
  • Join Date: Jul 2004
  • Posts: 255
    • old racer
EW running weak
« on: 03 Jun 2009 at 20:38 »
Hey Ho Banbury comming and the 1926 EW has suddenly decided to spit and bang in classic style if choke is opened up past half way
a.cleaned carb (including the little hole in pilot jet)
b.checked timing 3 3/4 inches of flywheel rim
c. repacked the inlet tract to cylinder joint-no leaks
d. points at 11 thou
e. tappets checked OK
f. plugs cleaned -changed  NGK A6
g good Petrol flow observed with float chamber top off
h tickler depresses and petrol flows

It is not running the curved pipe 'bellmouth' mainly because its missing but it has done two Banburys without it and ran fine.

What have I missed?

Offline roy

  • Senior Member
  • ***
  • Join Date: Aug 2005
  • Posts: 162
  • Location: Bath, Somerset,
Re: EW running weak
« Reply #1 on: 03 Jun 2009 at 21:42 »
Hi, I think it is the thought of "Sunrising" that puts them off, mine has done the same, but at the moment I am unable to give you the answer :twisted:
Roy.

Offline Ian

  • Master Member
  • ****
  • Join Date: Jul 2004
  • Posts: 1278
  • Location: The Oaks, NSW, Australia
Re: EW running weak
« Reply #2 on: 03 Jun 2009 at 22:40 »
Have you checked your valve guides ? badly worn inlet guides can cause this type of thing - although would have to be pretty bad !! Also possibly sticky valve.

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1554
  • Location: Hampshire, UK
Re: EW running weak
« Reply #3 on: 04 Jun 2009 at 05:46 »
Definitely check for a sticking valve - especially if you are running modern valves for use with unleaded fuel in cast iron valve guides. I have it on good authority from G&S Valves that the material the new valves are made of has a tendency to 'pick up' in cast iron guides. In the past, they have supplied us with valves that have the stems chrome plated. The other alternative, of course, is to change to bronze guides.
                             Regards,
                                           Eddie.

Offline tck

  • Senior Member
  • ***
  • Join Date: Jul 2004
  • Posts: 255
    • old racer
Re: EW running weak
« Reply #4 on: 04 Jun 2009 at 09:24 »
Before I have a look at the mechanical side a thought has come to me (sleeping on it helps!) since I stripped the carb for gum and blockages (and actually removed some) could I have reassembled the B&B carb back to front? where does the ' choke'  slide go?at the front of the throttle slide or the back? the picture I have is poor and the top is symetrical at the moment the top is located with the 'pip' at the rear as it should be and the 'choke is in the front cable abutment and the slide is in the rear -is that correct?

Offline roy

  • Senior Member
  • ***
  • Join Date: Aug 2005
  • Posts: 162
  • Location: Bath, Somerset,
Re: EW running weak
« Reply #5 on: 04 Jun 2009 at 12:58 »
Hi TK, Ref your carb slide, the choke should be at the front, (as you look into air intake).  Roy.

Offline roy

  • Senior Member
  • ***
  • Join Date: Aug 2005
  • Posts: 162
  • Location: Bath, Somerset,
Re: EW running weak
« Reply #6 on: 04 Jun 2009 at 20:31 »
 :lol: Eurica!!!!  EW now running smoothly.
Following Eddies suggestion I checked the valves and all timing settings and carried out the following;
a. Cleaned the points and reset them to 9 thou.
b. Fitted new Champion D16 plugs with 20 thou gap instead of NGK.
c. Emptied petrol tank and filled up with Tesco 97oct.
Tried her out for about 6mle. including quite a steep hill, never missed a beat.
Hope this may be of help.
Roy.

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1554
  • Location: Hampshire, UK
Re: EW running weak
« Reply #7 on: 05 Jun 2009 at 06:27 »
Following on from Roy's comments, here is another issue which may affect the running of our old bikes. From what I understand, the ordinary unleaded petrol is OK in our bikes - but may cause erosion of the valve seats - the higher octane unleaded could have a higher viscosity, thus causing the mixture to be weaker when used in an engine with a carburettor - so some jetting up may be required. Engines with fuel injection are less affected because a specific amount of fuel is injected on each firing stroke.
 When unleaded fuel was forced upon us, rather than spend out on having valve seats replaced, I figured that if valve seat erosion was going to be a problem, it would result in gradually reducing valve clearances, so adjusting the clearances would provide a temporary remedy to get me home. When the seats got really bad, then I could pay out for them to be replaced. The problem has never occurred, and  my bikes (Dragonfly, Comp and 2) are still running quite happily on the dreaded unleaded - and the Dragonfly does get worked unmercifully at times!
                           Regards,
                                       Eddie.

Offline tck

  • Senior Member
  • ***
  • Join Date: Jul 2004
  • Posts: 255
    • old racer
Re: EW running weak
« Reply #8 on: 05 Jun 2009 at 08:30 »
Thanks Roy and Eddie
I shall try some other plugs and raid my store of real TEL and add that (2%) to the petrol and do a double check on the path that leads up to the pilot jet from below.If I get a chance I will lap the valves in -or at least take a look but racing the Vincent at Mallory this weekend means time is short. again thanks

Offline roy

  • Senior Member
  • ***
  • Join Date: Aug 2005
  • Posts: 162
  • Location: Bath, Somerset,
Re: EW running weak
« Reply #9 on: 05 Jun 2009 at 09:46 »
Eddie, having noted your informative reply, do you use any additive in your machines?

Roy.

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1554
  • Location: Hampshire, UK
Re: EW running weak
« Reply #10 on: 05 Jun 2009 at 11:48 »
Hi Roy,
           Initially I did heed what the 'Prophets of doom' were saying regarding valve seat erosion, and added Castrol Valvemaster Plus to my fuel - then gradually reduced the percentage and kept an eye on the valve clearances. For about the last 4 years I have been running on neat unleaded without any apparent adverse effects. From personal experience, I have found brand of fuel has more effect than grade - my Dragonfly, in particular, does not like Shell petrol, and while competing in the ACU National Rally some years ago, I had no option but to use Shell (It was 5.30 in the morning and already on reserve). Immediately the bike was 10mph down on speed, then having found another petrol station, the tank was filled right up - and, hey presto, the speed returned. Dave Harris - also on a Dragonfly - experienced the same symptoms - in fact his engine tried to 'nip up'. Now, that has got to be more than just coincidence!
                             Regards,
                                             Eddie.

Offline graeme

  • Master Member
  • ****
  • Join Date: Oct 2004
  • Posts: 598
  • Location: Hobart, Australia
Re: EW running weak
« Reply #11 on: 06 Jun 2009 at 05:23 »
In Australia, Shell fuel is an absolute no-no in aircooled machines - particularly the higher octane "Optimax". This stuff is truly dreadful, fouling plugs by coating the porcelain with something that obviously conducts, so the spark never jumps the gap to to the elecrtode. I had terrible running on my T160 Trident, going through several sets of plugs until it dawned on me that the problem was the fuel. My brother and a couple of mates went through the same ordeal on their historic race bikes - using 10 plugs between them in one afternoon when using Optimax. They changed to BP the next day with no problems at all. Shell are evidently well aware of the problem, but how much of the market is using aircooled machines these days? Very few obviously, so to them it isn't an issue.
I should say that I have had no problems with other brands of fuel, BP, Caltex or Mobil being the main players here. As to fuel with ethanol in it, well that has been an issue - but from talking to a couple of fuel chemists it seems the problem is with unscrupulous servo owners doctoring the fuel with toluene - a well known scam here to avoid paying duty on the fuel.
Like Eddie, I also started using an additive with the fuel when leaded fuel disappeared, but have long since stopped doing so with no problems as far as valve seats go. I sometimes throw in a splash of 2 stroke oil as an upper cylinder lubricant when I remember to do so. I've been told this helps with engines generally, but in all honesty I think with the small mileages we do on most of our machines it's probably incosequencial. Having said that, a couple of the veteran machines have done a lot of miles over the years, particularly the 3 1/2hp outfit, which works pretty hard. I think I would have seen signs of valve seat recession in this machine if it was going to happen. So folks - don't be taken in by the doomsayers!
Cheers, Graeme

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1554
  • Location: Hampshire, UK
Re: EW running weak
« Reply #12 on: 06 Jun 2009 at 06:13 »
Here in the UK, I find either Total or Texaco fuel performs best in my machines - closely followed by BP or even Sainsbury's own brand. Tesco's own brand, whilst not giving any real problems, doesn't have the same sparkle (can you get sparkle with a Dragonfly???) - and as said before, I definitely steer clear of Shell.
                                   Eddie.

Offline roy

  • Senior Member
  • ***
  • Join Date: Aug 2005
  • Posts: 162
  • Location: Bath, Somerset,
Re: EW running weak
« Reply #13 on: 07 Jun 2009 at 17:53 »
Hi folks, have been away for the weekend, so a little behind.
With reference to Eddie/Graeme's statements about Shell, this could be the answer to the current problem I have with my Viper Clubman, like Eddie I had to fill up with petrol and Shell was the only option, since then it has been almost impossible to start.
I appreciate this is a Douglas site, so sorry to anyone who is offendend by the mentioning of another make of machine.
Regards to all, Roy.

Offline tck

  • Senior Member
  • ***
  • Join Date: Jul 2004
  • Posts: 255
    • old racer
Re: EW running weak
« Reply #14 on: 22 Jun 2009 at 15:08 »
Hey Ho Banbury comming and the 1926 EW has suddenly decided to spit and bang in classic style if choke is opened up past half way
a.cleaned carb (including the little hole in pilot jet)
b.checked timing 3 3/4 inches of flywheel rim
c. repacked the inlet tract to cylinder joint-no leaks
d. points at 11 thou
e. tappets checked OK
f. plugs cleaned -changed  NGK A6
g good Petrol flow observed with float chamber top off
h tickler depresses and petrol flows

It is not running the curved pipe 'bellmouth' mainly because its missing but it has done two Banburys without it and ran fine.

What have I missed?


Well Banbury over it finnished but  more due to the dexterity of my wife on the controls than all our engineering skills what a puzzeler that bike is  it is sometimes weak  mostly then again sometimes rich you can add many other items to the above list we have tried all to no avail what other carbs fit the EW is there a later clip fitting amal that I can try?

Offline Alan Cun

  • Master Member
  • ****
  • Join Date: Feb 2007
  • Posts: 431
  • Location: Qld Central Burnett District
Re: EW running weak
« Reply #15 on: 23 Jun 2009 at 08:41 »
Hello tck, I am thinking 11 thou is too close for the points particularly on a twin where the point gap can easily vary for each cylinder the return spring internal on the circumference of the cam cover can sometimes distort causing zero to one cylinder. Which makes it important to check points at both cams. Going back to eleven thou I thought it should be 15 thou and I have been told by some magy experts to set at 20 thou. Another important thing if you are using bakelite plastic plug fittings be sure that they are not resistance type.
You could also grab a couple of spare plugs and open the gap to around 30 thou and kick it over to see if you have a good fat spark. A fading spark could indicate crook condenser.

As an old breakdown mech order of repair, check spark, check spark, before fuel.

You can also check out previous posts on fitting the Amal as fitted to the B29's. Steve Mac  may be able to update on how his is progressing????????

regards Alan.
« Last Edit: 23 Jun 2009 at 08:46 by Alan Cun »

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1554
  • Location: Hampshire, UK
Re: EW running weak
« Reply #16 on: 23 Jun 2009 at 11:29 »
Tck,
       First of all I would check that the breather in the fuel filler cap is not blocked. Any restriction here could result in varying pressures in the fuel system - even changes in temperature (sunny then shade) or road conditions (fuel slopping about) will affect the rate of delivery to the carb.
                                Regards,
                                        Eddie.

Offline tck

  • Senior Member
  • ***
  • Join Date: Jul 2004
  • Posts: 255
    • old racer
Re: EW running weak
« Reply #17 on: 05 Aug 2009 at 11:08 »
Update on the 1926 EW
 Well I have checked all mechanics and given up on the B&B I have an amal 274 with a 1" clip fitting I need to order needle needle jet slide and main jet I suppose for main jet 130-150 is a starting point but does anyone have any other settings like slide cutaway etc?

Offline podge

  • Full Member
  • **
  • Join Date: Jun 2008
  • Posts: 65
  • Location: surrey, england
Re: EW running weak
« Reply #18 on: 05 Aug 2009 at 15:12 »
Hi TCK

I have a 1932 A32 350 cc with a 1931 EV series engine and an Amal 274 carb - see Members Gallery for photo. This engine is little different from the EW 350. I use a 65 jet, fourth position from the top on the needle and the cutaway is 4/4. It runs like a sewing machine on these settings.

Paul

Offline tck

  • Senior Member
  • ***
  • Join Date: Jul 2004
  • Posts: 255
    • old racer
Re: EW running weak
« Reply #19 on: 06 Aug 2009 at 16:04 »
Thanks Podge the4/4 is a good guide I think the 65 main jet may be a bit small for the EW and I guess 109 needle jet fits all I will wait and see if anyone else has some input before I order parts from surrey cycles

Offline Ian

  • Master Member
  • ****
  • Join Date: Jul 2004
  • Posts: 1278
  • Location: The Oaks, NSW, Australia
Re: EW running weak
« Reply #20 on: 07 Aug 2009 at 00:03 »
The 350 doesn't need a large main jet. If you convert the AMAC jet numbers for the TS to AMAL I think its about a 65 or 70 is the standard for that too.

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1554
  • Location: Hampshire, UK
Re: EW running weak
« Reply #21 on: 10 Aug 2009 at 16:05 »
If you are intending to use an Amal 274 carb of 3/4" bore, I would suggest that a good starting point for the settings would be: a 4/4 slide, no.4 needle, .107 needle jet and 75 or 80 main jet. Err slightly on the rich side on the main jet to help keep the temperatures down - the best performance is often obtained when the mixture is slightly weak, but can lead to other mechanical problems.
                             Regards,
                                        Eddie.

Offline tck

  • Senior Member
  • ***
  • Join Date: Jul 2004
  • Posts: 255
    • old racer
Re: EW running weak
« Reply #22 on: 10 Aug 2009 at 18:05 »
If you are intending to use an Amal 274 carb of 3/4" bore, ....                             Regards,
                                        Eddie.

Thanks again Eddie my order is in for parts lets see if that cures the problem, what a saga !Ive built and raced a Vincent since this started  :wink: