Almost there, problems starting

Anything related to Lambrettas... ask tech questions, post helpful info, or just read and learn.
User avatar
spannerman
registered user
Posts: 56
Joined: Wed Jan 07, 2009 8:56 pm
Location: PRESTON,LANCS.
Contact:

have similar problem with an Li125, rebored 150cylinder, rejetted carb(SH1-18) to what it should be . on points system .on starting up takes some persuading to rev, once started its a bit flat like over rich ,no oil as all joints are good. once hot refuses to start ,any ideas on that one please
User avatar
HxPaul
registered user
Posts: 1110
Joined: Fri Dec 06, 2013 1:58 pm
Main scooter: lambretta Li 150
Location: Halifax,Yorkshire
Contact:

spannerman wrote:have similar problem with an Li125, rebored 150cylinder, rejetted carb(SH1-18) to what it should be . on points system .on starting up takes some persuading to rev, once started its a bit flat like over rich ,no oil as all joints are good. once hot refuses to start ,any ideas on that one please
You say you've re-jetted the carb to what it should be,what jets have you put in.Its suggested for a standard Li 150 with an SH-18 the main should be 105,the pilot should be 45,the atomiser should be 5899-1 and the slide should be 5914-2.The choke jet,or starter jet is a standard 50.
Scooterdude
registered user
Posts: 796
Joined: Sat May 28, 2016 4:51 pm
Main scooter: Lambretta LI 125 S3
Location: Skaville
Contact:

Just a thought. I know you say you've done a leak down test a while ago but could it be possible your drive side oil seal has let go?
User avatar
spannerman
registered user
Posts: 56
Joined: Wed Jan 07, 2009 8:56 pm
Location: PRESTON,LANCS.
Contact:

yes thats how its jetted,plus new viton drive seals seals fit saturday,gonna do another pressure check as been out for short jolly and now taken exhaust of to get cleaned as a possible cause
User avatar
spannerman
registered user
Posts: 56
Joined: Wed Jan 07, 2009 8:56 pm
Location: PRESTON,LANCS.
Contact:

apologies it looks like ive hijacked a post ,so sorry for that ,just seems same issue
Scooterdude
registered user
Posts: 796
Joined: Sat May 28, 2016 4:51 pm
Main scooter: Lambretta LI 125 S3
Location: Skaville
Contact:

Don't want to tell you how to suck eggs but do the leak down test before you change the seals, that way you'll know.
Chris in Margate
registered user
Posts: 379
Joined: Thu Sep 03, 2009 7:53 pm
Main scooter: Lambretta 1964 225 Special
Contact:

He's using PWK 28.
Change the petrol and then rev the nuts out of it for a while; it might just be assembly grease and oil.
Must fix exhaust leak though.
User avatar
spannerman
registered user
Posts: 56
Joined: Wed Jan 07, 2009 8:56 pm
Location: PRESTON,LANCS.
Contact:

ref sealing joints I use HOLTS FIREGUM (sparingly)
User avatar
coaster
registered user
Posts: 3125
Joined: Wed Jan 07, 2009 12:35 pm
Location: London and Norfolk
Contact:

All the above are valid suggestions although I think a blowing seal is probably unlikely on a new build and you say it passed a leak down test. Are you using an air filter on the PWK and if so have you tried starting without it? Pattern PWK carbs like OKO need to have the float height set carefully, I forget the measurement but you should find reference on the ScootRs site. For the leaks, re-assemble using gigh temp silicone.
User avatar
spannerman
registered user
Posts: 56
Joined: Wed Jan 07, 2009 8:56 pm
Location: PRESTON,LANCS.
Contact:

firstly apologies to tippo88 on hijacking his post ,secondly as stated earlier have had exhaust cleaned out,was told there was a lot of crap came out of it ,(didnt seem that heavy when i took it out) Thirdly before refitting exhaust did pressure test for 10 mins (no leaks) only usually do 2 mins,and lastly it started up immediately ,sounds ok now, proof of pudding ,test ride tomorrow .
Thanks for all the help /suggestions hopefully this info will help others
Post Reply Previous topicNext topic
  • Information
  • Who is online

    Users browsing this forum: Google [Bot] and 24 guests