www.ukengineforum.forumotion.com
Please log in , the forum is open to guests who are now able to view most sections, feel free to become a member , you will then be able to post and reply to topics.

Join the forum, it's quick and easy

www.ukengineforum.forumotion.com
Please log in , the forum is open to guests who are now able to view most sections, feel free to become a member , you will then be able to post and reply to topics.

Petter A1 - Firing Problems

2 posters

Go down

Petter A1 - Firing Problems Empty Petter A1 - Firing Problems

Post by Ally's_Engines Thu Apr 16 2015, 11:47

I am making some improvements to my Petter A1 before rally season. I re-ground the valves, and after a re-assembly I gave it a test run. It pops fine and dandy, but there seems to be smoke coming out of the choke hole in the carb every time it starts. Do you think I have messed the tappet clearances when I was valve-grinding? Have I not ground the inlet valve enough? Any help is much appreciated.

Cheers,
Ally

_________________
You Tube channel: https://www.youtube.com/channel/UCYAohYdQQQy2TbKsIltrTKg
------------------------------------------------------------------------
1951 Petter A1, 1965 JAP model 6, 1950's Villiers mk10 compressor set, WW2 Douglas FT35, 1960's ATCO Villiers Lawnmower and Petter A2
Ally's_Engines
Ally's_Engines
Born to be wild
Born to be wild

Posts : 39
Join date : 2014-01-12
Age : 24
Location : Brechin, Angus

Back to top Go down

Petter A1 - Firing Problems Empty Re: Petter A1 - Firing Problems

Post by Woodsman Thu Apr 16 2015, 16:42

Hi Ally,
Tappet clearance should be 10 thou. Our newly acquired A1 was way out when we checked. If you have a nice matt line around valve and seat you should be fine.
I would have thought that lapping the valves would effectively lengthen the valve stem since the valves would be sitting lower in the seat. So the tappet clearance would be reduced and the inlet might open a little early. Best to check as it's an easy adjustment to make.

_________________
Regards Paul
Tha can alus tell a Yorkshireman - but tha can't tell him much.
Woodsman
Woodsman
Admin

Posts : 2656
Join date : 2014-08-24
Age : 72
Location : God's own county

Back to top Go down

Petter A1 - Firing Problems Empty Re: Petter A1 - Firing Problems

Post by Ally's_Engines Fri Apr 17 2015, 11:21

Hi Paul
I checked the clearance and it is at 10 thou on the dot. I'm just going to give her a long run and see if that makes any difference. Thanks for your help...

Regards,
Ally

_________________
You Tube channel: https://www.youtube.com/channel/UCYAohYdQQQy2TbKsIltrTKg
------------------------------------------------------------------------
1951 Petter A1, 1965 JAP model 6, 1950's Villiers mk10 compressor set, WW2 Douglas FT35, 1960's ATCO Villiers Lawnmower and Petter A2
Ally's_Engines
Ally's_Engines
Born to be wild
Born to be wild

Posts : 39
Join date : 2014-01-12
Age : 24
Location : Brechin, Angus

Back to top Go down

Petter A1 - Firing Problems Empty Re: Petter A1 - Firing Problems

Post by Woodsman Sat Apr 18 2015, 10:55

Hi Ally,
Can you feel it blowing from the carb on the compression stroke if you put you hand over the inlet? That might indicate that the inlet valve is not seating properly.
You could also check the gasket - maybe it's leaking across from exhaust port?

_________________
Regards Paul
Tha can alus tell a Yorkshireman - but tha can't tell him much.
Woodsman
Woodsman
Admin

Posts : 2656
Join date : 2014-08-24
Age : 72
Location : God's own county

Back to top Go down

Petter A1 - Firing Problems Empty Re: Petter A1 - Firing Problems

Post by Ally's_Engines Sun Apr 19 2015, 15:14

I'll give that a try thanks Smile

Ally

_________________
You Tube channel: https://www.youtube.com/channel/UCYAohYdQQQy2TbKsIltrTKg
------------------------------------------------------------------------
1951 Petter A1, 1965 JAP model 6, 1950's Villiers mk10 compressor set, WW2 Douglas FT35, 1960's ATCO Villiers Lawnmower and Petter A2
Ally's_Engines
Ally's_Engines
Born to be wild
Born to be wild

Posts : 39
Join date : 2014-01-12
Age : 24
Location : Brechin, Angus

Back to top Go down

Petter A1 - Firing Problems Empty Re: Petter A1 - Firing Problems

Post by Sponsored content


Sponsored content


Back to top Go down

Back to top

- Similar topics

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