Villiers Lightweight 515H difficulty starting!

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ChrisHGTV
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Villiers Lightweight 515H difficulty starting!

Hello all,

My first post as a member - I acquired a circa 1966 British Anzani Lawnrider from Clive (Many thanks Clive!) that I'm in the process of restoring/preserving.  It's a wonderful machine and so far enjoying the project, though I seem to be buying new tools for each operation at the moment!  
 

So my issue I wonder if anyone can advise on - the problematical engine.  So far I have thoroughly cleaned everything, new spark plug, electronic ignition, new carb float needle, the part the needle goes into, new air filter, gaskets, fresh oil etc.  I have had it running and it sounds fine but it's really reluctant to start.  The carb (b10/1) seems to have a tendency to flood with fuel leaking out of the strange brass "breather" in the bottom section.  I have the pilot screw adjusted as per the handbook two turns out from closed and holding the throttle open about 1/3.  I have a good spark, timing is fine, valves all move etc and it does run.  I'm assuming it's the carb that's the issue but at a loss what to look for or try next, any ideas?

Many thanks!

Chris

wristpin
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Two thoughts. You mention

Two thoughts. You mention “the valves moving” but did you have them out , check the condition of their faces , reface them and recut the seats - if necessary,  or at least lap them in and set the correct clearances?. Secondly, ignition timing. You mention electronic ignition and timing - is it an original electronic system or just an after market trigger unit replacing the contact breaker points and condenser?

I’m not aware that the Lightweight was ever fitted with an electronic / solid state system from new but if it has and follows the setup of other Villiers engines the timing is fixed so there’s nothing to be done there.  If it originally had points and condenser it’s wise to ensure that that the stator is positioned to give the correct timing before removing the points and condenser and installing the trigger module.

Either way, it’s my experience that electronic systems do require higher cranking rpm than points systems - good firm sharp pull from the compression point  - not a snatch.

Probably a good idea to eliminate the flooding  - perhaps lapping the float needle to its seat with some metal polish will settle it.

 

 

ChrisHGTV
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Thanks for the reply wristpin

Thanks for the reply wristpin.  Hmm I've not had the valves out, just inspected with the head off, as best as I could see with a torch.  Maybe I should give them a proper check etc as you suggest.  The electronic ignition is aftermarket from George at Villiers Parts.  He sent very clear instructions which I followed - so set to TDC both valves closed compression stroke and then line up the arrow on the flywheel to the mark on the casing at 12 o'clock.  So hopefully timing should be ok.

Ill have another look at the carb...

So, a couple of things to check - many thanks I'll report back!

wristpin
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That’s interesting as I wasn

That’s interesting as I wasn’t aware that there was an electronic stator available for the Lightweight. If it’s the “original” Villiers/Wipac unit my experience on other engines factory fitted with them from the outset  is that they do need a more determined pull over to fire them up than the same engine with the points system. 

When it comes to valves, I’m a great believer that to get the best out of an older engine, having the valves “ spot on” is time well spent compared with time wasted fiddling around with carburettion and timing on an engine that may be feeling it’s age. I learnt a lot many years ago from a man who would say “ remember VICTOR” - valves , ignition, carburettion  - in that order. 

ChrisHGTV
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Ah ok, let's take a look at

Ah ok, let's take a look at the valves then!  So the head is off again and I just need to pick up a tool tomorrow to compress the springs to remove the valves.  I have a valve lapping kit so that's a job for tomorrow!  It seems daft not to do it anyway seeing as the engine is bolted to my workmate and everything is accessible.  Thanks again!

wristpin
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Valve clearances 2-6thou” for

Valve clearances 2-6thou” for both which is a fairly generous margin so I’d aim for 5 as they tend to close in use.  Before you start on the valve removal, check the tappet clearances as it will give you a rough idea what you may be faced with. If ,for instant, you can’t get even a half thou feeler in you will know that you will have to remove at least the maximum allowance from the stem - plus whatever you may have to remove from the valve face and seat .

With the valves removed, clean them up and if you have any concerns post some images . Most tins of valve grinding paste have a coarse and fine end. The general rule of thumb is that if the valve won’t clean up with the fine paste, don’t grind away with the coarse - have them refaced and the seats skimmed.

 

 

ChrisHGTV
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It lives!  Many thanks for

It lives!  Many thanks for your wise words wristpin.  I checked and cleaned up the valve seats and adjusted the gaps.  The exhaust wasn't too far out but the intake was way out - the gap too large so I think a new valve had been fitted at some point and not fully installed/adjusted.  Both gaps are now 5 thou.  With the head off I also checked that the timing marks on the flywheel still lined up, all was fine.  I used some autosol  on the float needle and seat and raised the needle a tad.

A couple of good pulls and it started!  So thanks again for steering me towards the valves wristpin, I'm sure that was the main issue.

I had to make a new tool to compress the valve springs- a bit of dremel work on a £2.69 door trim removal tool from euro car parts did the job.

I also picked up a useful trick (can't remember where I saw it) - I used 3 small zip ties to compress each spring to install.  Worked extremely well.

So now on to the rest of the machine!

 

 

 

wristpin
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I also picked up a useful

I also picked up a useful trick (can't remember where I saw it) - I used 3 small zip ties to compress each spring to install.  Worked extremely well.

Valve spring ties. You may have seen it on this forum. A while back, another member used it successfully on a Villiers F12 and posted images . If you find  a “ full fat” Lightweight overhaul manual you will see that the long obsolete Villiers valve tool is a modified pair of square nosed pliers. 

All good that it’s up and running with less effort.