Petter A1 restoration

Here is the first post of my Petter A1 that I have been given to restore. Here it is when I first laid eyes on it:



It's a bit hard to make out but the serial number is 1517038


Other than that I have no idea of its history, where it came from or how long it has been like this. Since then I have got it onto a makeshift trolley for moving it around easier and acquired a shed to keep it in the dry.

Things I have found so far:

• It turns over fairly smoothly so I presume it isn't totally seized internally.
  
• The carb linkages and moving parts are all stuck.
  
• I don't think it has any compression. I can't be sure without taking some more things off to see but I think the exhaust valve is stuck.
  
• Having done some research on timing the engine, there is no click from the magneto at TDC. Is this a bad sign?
  

So it looks like there are going to be a lot of things on my to-do list!

Chris

It can only get better, looks a good project sounds like there's a lot of parts that need freeing up.

Alan

That’s most likely late 1952 based on my own engine.
Stuck exhaust valve is pretty much nailed on and not too difficult to fix.
The impulse spring of the magneto is best checked after removing from the engine as the floating coupling may be broken.

Having had some free time over the weekend to make some progress, I thought I ought to post an update!

Freeing up the dipstick


Still plenty of oil in the sump!


Removing the fuel tank


Removing the top cowl


Quite a lot of corrosion on the cylinder head


Loose corrosion brushed off


Removing the cylinder head bolts


Needed gentle tapping and slowly freeing off due to corrosion on one of the studs


Cylinder head removed, not too bad inside



Exhaust valve freed up, now moves as it should


Bore seems to be in good condition



Carb removed for cleaning and freeing up

How’s it going Chris?

Hi Andy, was going to come on here today to post an update as it happens! I don't always have a lot of free time to work on this, especially now as the evenings are getting shorter

Carb has been taken off the manifold and separated to see what's what:





Float valve is nice and free as is the throttle lever. I have also freed up the choke lever by repeated soaking in oil and gently working free. I'll probably get a new spring for it as this one is quite rusted up.

I have also removed the magneto as that is the next thing to look at as I have no idea whether it works.



The impulse coupling does not click when rotated so I taken the cup off to have a look:



It all looks pretty rusted up in there, maybe a new spring is required?

I have had a look at the other bits but I am struggling to understand how it actually works. I can't seem to find any videos or guides on what is supposed to do what. Is the arm meant to be sitting outwards and jam against one of the pins to wind the spring up? Should it be loose and free to move?



Any help gratefully received!!

Yes the arm must be free to move, at low speed it should collide with the post at the bottom in your bottom picture and wind the spring to the point where it trips. At higher speed over 165rpm the centrifugal force throws the arm out so it misses the post. If the spring isn't broken it should be fine after a good soak in paraffin.
You carb looks to be a good one, I've just refurbished the one that came with my W1H

Thanks Andy, that's really useful

I'm going to give things a good soak and clean in paraffin and see where are from there!

Chris

You might find this helpful if you haven't already found it.


Also

I have some generic info on magnetos plus some WICO stuff.
PM me with your email address if you would like copies

Evening, looking at the state of your magneto your main concern is going to be the coil, I don't know the readings required but you should check the continuity of the coil to make sure its sound as that will be your most expensive item to replace or repair.

Maryalice

maryalice wrote:Evening, looking at the state of your magneto your main concern is going to be the coil, I don't know the readings required but you should check the continuity of the coil to make sure its sound as that will be your most expensive item to replace or repair.

Maryalice

Thanks for that, that is something I do need to check as I have nothing to go on!

I have seen posts/videos on testing the coil, I believe I need to see a figure of around 5.something at the 20kohm resistance setting on the multimeter.

I wouldn’t be concerned as the bsa bantam coil conversion is under £15

Quick update: managed to have another look at the impulse coupling yesterday. Now that things have been freed up and oiled, the spring and pawl move OK now and I can get the pawl to jam against the stop to wind the spring up. It needs quite a bit of strength turning by hand to release the pawl and get it to snap but it does work again.

Meant to look at the coil resistance too, but as I don't have a multimeter at home it'll have to wait to later in the week until I have access to one again.

cknotty wrote:
Meant to look at the coil resistance too, but as I don't have a multimeter at home it'll have to wait to later in the week until I have access to one again.

Screwfix do some which are perfectly adequate for tinkering with engines.  Check reviews first!
I got mine from my local German discounter

Here are the results of the coil testing:





Not sure whether this is good or not, but I thought I'd connect up the lead and wind it up like I've seen in several videos, and it sparks!



I know there isn't a spark in the photo but I couldn't hold it and turn the magneto at the same time!

You want the meter set on the 20KOhms scale, should get around 3-5KOhms measuring from the HT lead to earth. looks like your getting 56Ohms which is very low.

I couldn't quite see the scale, but if you're getting around 3 to 5 kOhms as Steve says, that's probably good news.  
See also my comments in matt's thread about testing using a big gap.

https://ukengineforum.forumotion.com/t11128-villiers-mk12-issue#82815

Woodsman wrote:I couldn't quite see the scale, but if you're getting around 3 to 5 kOhms as Steve says, that's probably good news.  
See also my comments in matt's thread about testing using a big gap.

https://ukengineforum.forumotion.com/t11128-villiers-mk12-issue#82815

056 on the 200 Ohms scale

That looks more like LT, maybe a short then?  Can't see what you connecting to, I presume directly between the HT tab on the coil and earth. Try a couple more pictures please showing how you are connected.
Also don't understand how you are getting any spark with that low a resistance.
Keep at it ! You'll get there.

Woodsman wrote:That looks more like LT, maybe a short then?  Can't see what you connecting to, I presume directly between the HT tab on the coil and earth. Try a couple more pictures please showing how you are connected.
Also don't understand how you are getting any spark with that low a resistance.
Keep at it ! You'll get there.

Thanks Paul! I did another check with the multimeter set to 20k as mentioned earlier & got a value of 0.02, so it does seem low. This was between the HT tab at the top of the coil and one of the screws on the body where one of the coil wires is attached.

I'll try again with a new spark plug and see how I get on - got to get the carb back together!

On another note, are there any places where I can get a head gasket? SEP is currently showing out of stock

cknotty wrote:
I did another check with the multimeter set to 20k as mentioned earlier & got a value of 0.02, ....

Your first pic shows a reading of 0.005 when range set to what looks like 2K.  Doesn't seem right.  
As you change ranges you should get the same figure(ish) with the decimal point moved.
Are you sure the meter is OK?

Thread resurrection! Having bought up some replacement bits I took some time off work to make some progress with this:

Magneto back on and timed: I now get a satisfying clunk at TDC! Tested with a new plug and lead, and I am getting a spark

Carb now all freed up and put back together with a new gasket.

The engine didn't have an exhaust silencer fitted but came with a spare manifold and cast iron silencer attached. The carb didn't match up to this manifold unfortunately (possibly an older manifold for a Solex carb?), so the silencer was removed (with a lot of persuasion!) and is now on the manifold that was on the engine originally.

I am now regrinding the valves and cleaning off all the carbon deposits on the inside of the head so then hopefully I can refit the head with a new gasket.

Chris