www.stationaryengineforum.net
Please log in , the forum is open to guests who are now able to view every section, feel free to become a member , you will then be able to post and reply to topics.

Timing a Petter. Carbon plug

View previous topic View next topic Go down

Timing a Petter. Carbon plug

Post by Pettercutter on Sat Aug 17 2013, 16:27

I have got my Petter AS 3BHP running few days ago but had trouble starting it today. On removing the plug I found it heavily fouled with carbon. I suspect the timing so reread the Petter Instruction book and confirmed that the impulse starter should click just before the piston reaches TDC. This seems about right but the manual goes on to say that you can check the timing with the impulse trip out of action by turning the engine in the wrong direction and then with a thin piece of paper (Rizla...) between the points the exact instant of the breaker opening can be determined and at this point the magneto is in the position where the spark is delivered to the cylinder.

When I do this I get a completely different story and the paper comes loose with the flywheel miles away from the arrow marking 20 degrees before TDC.

Any idea why this might be so and would this cause the carbon buildup?

Pettercutter
Born to be wild
Born to be wild

Posts : 28
Join date : 2013-06-20

Back to top Go down

Re: Timing a Petter. Carbon plug

Post by Villiers on Sat Aug 17 2013, 16:34

Sounds like the timing is way out then, about all you can do is time it up "backwards" with the rizla and see how you get on from there. Am I right in saying your AS has the gear driven mag? I know the AHM is chain driven and if the chain is loose this could affect the timing when turned backwards.

And just make sure you are using BLUE Rizla papers, green ones are too thick.....Wink 

Villiers
Life Member
Life Member

Posts : 975
Join date : 2010-01-02
Age : 48
Location : Just outside Diss

http://www.rcoleplumbingservices.co.uk/

Back to top Go down

Re: Timing a Petter. Carbon plug

Post by Pettercutter on Sat Aug 17 2013, 17:00

OK I gave it another go and think I see what I did wrong...I read that you turn the engine backwards and kept going backwards till the gap opened up but now see that yo go backwards to put the impulse trip out of action then go forwards to get the points to open up.Doing this I can get the firing point to about 15 degrees before TDC...but I have run out of movement on the magneto as it is turned as far as it can go clockwise. Having lost the original magneto coupling (OK I may as well admit it, burnt..) the new one we made might be slightly off so that would explain why I can't get to the exact 20 degree before TDC point. It runs at present although I am sure it should run smoother than it does.

Pettercutter
Born to be wild
Born to be wild

Posts : 28
Join date : 2013-06-20

Back to top Go down

Re: Timing a Petter. Carbon plug

Post by Pettercutter on Sat Aug 17 2013, 17:04

And yes the Rizlas are blue!Very Happy 

Pettercutter
Born to be wild
Born to be wild

Posts : 28
Join date : 2013-06-20

Back to top Go down

Re: Timing a Petter. Carbon plug

Post by Villiers on Sat Aug 17 2013, 17:04

http://www.ebay.co.uk/itm/GENUINE-LISTER-PETTER-TD113-MAGNETO-COUPLING-327041-/261252906835?pt=UK_BOI_FarmingEquipment_RL&hash=item3cd3e2ff53

Bloody good price though!!

Villiers
Life Member
Life Member

Posts : 975
Join date : 2010-01-02
Age : 48
Location : Just outside Diss

http://www.rcoleplumbingservices.co.uk/

Back to top Go down

Re: Timing a Petter. Carbon plug

Post by michael3 on Sat Aug 17 2013, 20:57

If the AS is anything like the A1, ie gear driven mag, you may need to move the mag on or back one tooth to give yourself the timing range you want.

michael3
Expert
Expert

Posts : 77
Join date : 2013-05-13

Back to top Go down

Re: Timing a Petter. Carbon plug

Post by Pettercutter on Sun Aug 18 2013, 08:50

OK will have a look into it but not for a while now as I have to go away for a few weeks...will try again in the autumn. Thanks to everyone for chipping in! cheers James

Pettercutter
Born to be wild
Born to be wild

Posts : 28
Join date : 2013-06-20

Back to top Go down

Re: Timing a Petter. Carbon plug

Post by Sponsored content Today at 15:59


Sponsored content


Back to top Go down

View previous topic View next topic Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum