Hello to all.
Model 9 1934
I am having trouble starting, i do have a decent spark and the timing seems right.
However having kicked and kicked a lot of times and with fuel dripping out of carb nothing. On checking the plug it was dry and no smell of fuel.
I had previously had the carb off, fully stripped/cleaned and put back together with new needle and jet. After checking fuel level against air mixture screw everything looked ok.
Could there be a reason why fuel is not getting through or something else i have missed.
Any thoughts would be appreciated.
Cheers
Peter
Hi Peter, I assume that the timing is corrctly adjusted and you've set it to 2/3 advanced when starting. Cheers, Thomas
Hi Thomas
What is the best way to check the timing?
Peter
For your Model 9 the timing must be set at 9/16 inch BTDC. At this position the contact breaker points should just open with the handlebar lever is fully advanced (the lever rotates the timing plate under the points). In practice you pull out the plug and use a wooden stick for the correct piston position BTDC after the inlet valve has closed. To see when the points open you clamp a thin foil between them and pull (see pic). They open when the points reach the chamfer (arrow) on the ignition plate unter the points. Then you can just pull the foil out. If they open at a position different to 9/16 BTDC you need to loosen the timing sprocket on the magneto under the timing cover (I recommend the respective tool) and rotate the axle until the points open (the piston must not move). Fasten it again and that's it.
Thomas
Thanks for that, a very good detailed explanation 👍👍
I will give it a check.
Many thanks
Peter
Thomas
I made a tool to indicate tdc and put a measurement of 9/16 back.
At 9/16 btdc i could get a 2 thou feeler gauge in between the points so it looks like the points are opening early.
You mentioned a tool to make adjustments is it special?.
I looked at the club shop to see if they sold one but couldn't see anything.
The handbook doesn't show any pictures of how to adjust just says 'alter the timing'!!
Cheers
Peter
This is the tool I am talking about, Peter: https://marston-sunbeam.org/sunbeam_shop/index.php?id_product=329&rewrite=mag-pinion-extractor&controller=product
I didn't ever see a pic for the timing adjustment. But basically you can simply follow my description. As soon as the sprocket is off you can easily turn the magneto shaft and then you put the sprocket on again.
Cheers, Thomas
Thanks Thomas
I saw that on the website and didn't realise that was what it was for!!
I will send for one.
Thanks again for replying its good to have a helping hand.
👍👍😁
Peter
I understand your appreciation, Peter. The forum is not too active although there are Beamers who need support. Anyway, I do my best to help if I can, especially because I got a lot of help from others.
Cheerio
Quote from: Peter 100 on August 11, 2025, 10:14:16 AMHello to all.
Model 9 1934
I am having trouble starting, i do have a decent spark and the timing seems right.
However having kicked and kicked a lot of times and with fuel dripping out of carb nothing. On checking the plug it was dry and no smell of fuel.
I had previously had the carb off, fully stripped/cleaned and put back together with new needle and jet. After checking fuel level against air mixture screw everything looked ok.
Could there be a reason why fuel is not getting through or something else i have missed.
Any thoughts would be appreciated.
Cheers
Peter
Why not start off by doing the simple things first?....like change the plug for a new one (remember new plugs can be duds straight out of the box so try a couple) as it may have broken down due to excessive heat exacerbated by the very Hot weather we've been having sometimes plugs appear to be giving a spark but actually it's not a good spark because the insulation is breaking down as I said due to excessive heat I sometimes go up a heat code to compensate in very Hot Weather.....but to be honest it sounds like a blocked needle jet or a blocked pilot jet to me especially if the plugs staying dry then it would seem no fuels being sucked into the cylinder head....if changing the plug doesn't do anything I'd take the next easiest step and that is take the carb off strip it down including the Float bowl it may well be full of old petrol gundge blocking everything up give everything a good clean buy yourself a set of carb cleaning pin rods and brushes be careful using them when rodding through the very small jet holes then re-assemble give the pilot jet 2 1/2 turns out make sure you got the throttle needle set on the same notch you had it on originally tickle the the carb until you see a small amount squirt out of the float chamber 2 priming kicks then give the full monty......if it still doesn't start don't be tempted to keep tickling it it wont help oh yeah in this Hot weather make sure your choke lever is in the fully open position before you start to kick it over I'd also run a bit of lint free paper (back of some emery cloth) through your points make sure they're clean and pit free and don't forget to check the gap something like .015" - .020"......remember do the simple and easiest things first it's usually that.................if you do these 2 things by my reckoning it should start.....or at the very least you should be getting fuel into the cylinder and the plug should be getting wet....if that's the case then you'll need to look at your ignition timing as said
Peter
Weirdly I have a very similar problem on my 1931 model 9 twin port. It simply will not start - despite starting beautifully hot or cold beforehand. The only change I effected was to adjust the tappets (to 10 thou for EX and fag paper for IN) as it sounded a wee bit tappety and lower the needle a notch. Since then, utter zip. I have racked my brains trying to understand if what I did affected things, but to no avail. Since then, I have done the following - which may help you with your problem
Changed the plug - NGK AB6
Pulled the mag and thoroughly tested it on a special rig. Good strong durable spark. No issues.
Checked HT lead at the mag
Checked HT lead to plug connection - no cap used, just an eye at present.
Cleaned up the mag slip ring
Checked all earths
Cleaned out the carb, all jets and wee holes, pulled the block - checked that, cleaned out all the pilot air holes/jets
Checked float- gave the valve a very minor lapping with the seat
Checked the points- the cam face and the cam itself.
Checked if gasket at carb union nut was fouling the inlet for the fuel to the pilot - it wasn't
Lapped the mag pinion to the mag shaft - in case it was slipping
I cannot think of much else save a compression test - which I will do shortly, and/or pull the head to see if anything is amiss.
It is driving me nuts for sure......
Oggers
You have done a lot more than me!!
I did mention in my first post that i didn't think i was getting fuel through as plug was not wet or smelled of petrol, are you getting petrol through??
Peter
Russ
Only just noticed your post thanks for the advice. I have fully stripped the carb (that bottom big threaded cap was an bas****d to get undone but came loose eventually) I will try another plug as you say, but as i said to Thomas the points seem to be ever so slightly open before 9/16 btdc. I only had the pilot screw out 1.5 turns so will 2.5 also.
Cheers
Peter
Fellow Beamers thanks for all your advice something did the trick cleaned and checked points/timing, adjusted pilot screw, put an old plug in, choke off, and the old girl fired up and ticked over.
Thanks again
Pete
Oggers i hope you have some good fortune like i seem to have had!!
Quote from: Peter 100 on August 12, 2025, 05:06:35 PMRuss
Only just noticed your post thanks for the advice. I have fully stripped the carb (that bottom big threaded cap was an bas****d to get undone but came loose eventually) I will try another plug as you say, but as i said to Thomas the points seem to be ever so slightly open before 9/16 btdc. I only had the pilot screw out 1.5 turns so will 2.5 also.
Cheers
Peter
if your points are opening a fraction before 9/16" BTDC shouldn't really make a whole difference to the starting procedure as you should have the ignition retarded before 9/16" for starting say a 1/4 to 1/2 the of the mag lever movement if your points are opening slightly before 9/16" BTDC it will likely affect top end ignition and power....you should be setting the ignition timing on the compression stroke with the mag lever in the full advance position before setting the timing to 9/16" BTDC and don't forget it's not spot on precision engineering imagine you were stuck at the side of the road trying to adjust ignition timing and trying find 9/16" BTDC with a lolly stick and a fag paper between the points and you'll know what I mean about not that precise....LOL.....but that aside it's always best to get the ignition timing bang on using a dial gauge down the plug hole (or better still with the head off and a timing disc on the end of the crank.......you'll get it sorted in no time.....I'm betting it's something simple (Plug / lead or Carb) if the bike started before you put it in the garage it didn't suddenly break doing nothing on the stand.....LOL......it won't be something major......I doubt this will be the cause but here's another thought make sure your pushrod adjusters haven't come loose and messed up your valve timing....................
those pesky plugs and gummy carbs.....well done......top tip....always keep a spare plug on you especially when riding in these very hot ambient temperatures.....now get yerself down the pub for a test run....LOL
Cheers Russ 🍻🍻🍻
Pete
If only the solution to my issue were so simple! I have a feeling I am missing something blatently obvious! Plug seems wet, and after stripping the carb twice now and observing it overflowing after tickle, I cannot see how fuel is not getting in there. I cannot think it is ignition given what I have checked out. I'll try new plugs and a compression test may yield something, as may removing the head. It is just incredibly annoying after it ran so well and me doing very little to it.
Quoteimagine you were stuck at the side of the road trying to adjust ignition timing and trying find 9/16" BTDC with a lolly stick and a fag paper between the points and you'll know what I mean about not that precise
I suppose we all have a very precise 9/16 spanner in the tool box rather than a lolly stick.
Quote...or better still with the head off and a timing disc on the end of the crank...
Hm, I intentionally didn't mention the timing disc method because it is not as accurate as the method with a (wooden) stick. Why? The piston position follows a trigonometric curve and its variation is pretty small at TDC while a disc follows a linear function in degrees. I was never satisfied with its accuracy and came back to the gauge. And don't take the head off for the timing. ;D
Quote from: oggers on August 13, 2025, 10:57:49 AMPete
If only the solution to my issue were so simple! I have a feeling I am missing something blatently obvious! Plug seems wet, and after stripping the carb twice now and observing it overflowing after tickle, I cannot see how fuel is not getting in there. I cannot think it is ignition given what I have checked out. I'll try new plugs and a compression test may yield something, as may removing the head. It is just incredibly annoying after it ran so well and me doing very little to it.
drain the Sump of oil as wet Sumping can cause starting issues
Quote from: oggers on August 13, 2025, 10:57:49 AMPete
If only the solution to my issue were so simple! I have a feeling I am missing something blatently obvious! Plug seems wet, and after stripping the carb twice now and observing it overflowing after tickle, I cannot see how fuel is not getting in there. I cannot think it is ignition given what I have checked out. I'll try new plugs and a compression test may yield something, as may removing the head. It is just incredibly annoying after it ran so well and me doing very little to it.
I'd be inclined to reverse the changes you made (needle notch?) but also check the pilot jet too. You have to remove the carb, undo the big base nut and GENTLY drive the brass block out of the body. A short bit of old broomstick is useful to tap against the brass block. The pilot jet is not removable, but is a tiny drilling in the brass block. Blow through with an airline or blast with carb cleaner. Last resort use a bit of fine soft wire to probe the hole - you can't push it right through as the jet has drillings at right angles.
I find that old singles are fussy about being flooded so use the tickler sparingly. If petrol is dripping out of the intake it is unlikely to start - so fuel tap off, take the plug out and clean fuel off, kick over a few times to clear the excess fuel then try again.
HTH
Sigarus and Russ
I don't know if your lastest comments were for me or Oggers as mine seems to have been sorted and now fires up. I think they are most probably now more of interest to him, i hope he reads them.
Thanks for the imput all the things you all suggest are much appreciated as my knowledge in vintage bikes is pretty limited, although learning all the time.
Peter
Sigarus - All done previously. Thanks anyways.
Russ - When removing the mag pinion the casing had to come off as did all the oil pipes and thus the return from the sump. Not sure if this drained the sump adequately - probably not - but I will drain it from the plug - is there a plug - I forget? I know what you mean and it may be a good shout. The oil build up could prevent the mag turning fast enough to generate that vital initial spark.
Quote from: oggers on August 14, 2025, 09:43:57 AMSigarus - All done previously. Thanks anyways.
Russ - When removing the mag pinion the casing had to come off as did all the oil pipes and thus the return from the sump. Not sure if this drained the sump adequately - probably not - but I will drain it from the plug - is there a plug - I forget? I know what you mean and it may be a good shout. The oil build up could prevent the mag turning fast enough to generate that vital initial spark.
That's exactly the issue with wet Sumping when the Sump is full of oil you'll do well to get the crank spinning up fast enough to catch a spark you only need about 100 to 150ml of oil in the sump 3 or 4 pumps of the hand pump should suffice (if you got one) otherwise use a mechanics syringe there should be a drain plug either on the side of the crankcase near the bottom or underneath.....but just for a test start it doesn't matter if there's oil in the sump or not providing you stop the engine after 30 seconds or so after it starts (if it starts)......give it ago
A slightly blocked pilot hole avoided easy starting my 1932 M9 in the beginning. After cleaning all the little holes in the carburetor very accurately, the motorcycle is starting normally with the first or second kick.