Li150 seized. What do you think.

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dragoonpvw
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Posts: 36
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Main scooter: Lambretta Li 150
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So here is where I am and where I have been.ImageImageImageImageImageImageImageImageImage

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dragoonpvw
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Posts: 36
Joined: Thu Oct 25, 2018 5:02 am
Main scooter: Lambretta Li 150
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New piston, crank, seals, head rebore to 57.6, clean all rust offer head and repaint along with cowling etc. New stainless hardware. Clutch cable etc. I think I should be going in a short time. ImageImage

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Warkton Tornado No.1
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I don't know if it's not been mentioned before, but, if I missed it, I should apologise. Either that barrel has been aluminium sprayed or it appears to be one of the cheap Indian barrels that are available.

If it is the latter, I would advise you to thoroughly check the ports. If the new crank & seal plate are silk purses, then Indian barrels are usually the pig's ear.

They can be made to work well, but take a lot of time in tidying & optimising (particuarly the transfers) to get the best from them. I realise you are not after a street racer, but having got this far, it seems you should @ least check timings, head volume, squish etc. There is also the added satisfaction to be gained in knowing that the finished result is the best that it can be. You did say you were an engineer, didn't you? ;)

You could post some images of the bore for us to comment further......
dragoonpvw
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Posts: 36
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Main scooter: Lambretta Li 150
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Don't worry, its the original innocent barrel. I cleaned it by wire brushing all the rust off it, painted it with engine paint to keep it looking clean and preventing rust. I had it overbored to 57.6, 3rd oversize then I fettled it by cleaning and chamfing all the ports. I am going to do the squish and timings next few days .The exhaust port was 20% blocked ny carbon so the engine should be so much happier after cleaning and the inlet was pretty cruddy too. I couldn't get it blasted nearby so it was all done with wire tube brushes, what a pain but I am really pleased with how it came out. The faces were in great shape as I don't think the head has ever been off since new. The original gaskets had 55 year old shellac on them, It took about three days soaking with a special gasket remover and gently scraping them every few hours and reapplying to get them off without any scratching or damage to the mating surfaces. It was worth it as the bike is still pretty much original. I will find out how perfect as I used a new head gasket and fitted it dry per spec , I will do a leak down to see. I have learned a lot in the last few weeks and am pretty comfortable making sure everything will be right. Im not an engineer, I am a photographer, but I was on chieftains in the Army so my mechanic work started there, I do all the maintenance on a bunch of family vehicles, from a 1971 rolls to a 45 foot diesel yacht. Not my vehicles but parents. I just was called in by a local garage to work on a 1961 Rolls as there are no mechanics around that can work on them. I think I am lucky , as I love doing it.
Anyway, I think it looks pretty good as I did all the work myself except for the boring.
dragoonpvw
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Posts: 36
Joined: Thu Oct 25, 2018 5:02 am
Main scooter: Lambretta Li 150
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This is the before and afterImageImageImageImage

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wrecklessrobbie
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Joined: Thu Jan 09, 2014 7:34 pm
Main scooter: li150
Location: York
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You have done a very good job of cleaning the engine. Very impressive :D
dragoonpvw
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Posts: 36
Joined: Thu Oct 25, 2018 5:02 am
Main scooter: Lambretta Li 150
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Got it in today, should be running by Monday, making sure all rattles and squeaks are gone. Then timing tomorrowImage

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holty
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Location: east yorkshire
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very nice job, well done on a methodical rebuild, its nice to see such attention to detail.
dragoonpvw
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Posts: 36
Joined: Thu Oct 25, 2018 5:02 am
Main scooter: Lambretta Li 150
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Success. three kicks to start then first kick every time after. A little smoke at first but probably burning off assembly lube, a little uneven idle at 2100rpm and its a bit bright to see my timing light. Nevertheless, total success so far. Dead chuffed. I might need to learn how to adjust the carb as the exhaust is breathing freer and all the ports are cleaner too. Any advice on a methodical step by step to get it running smoothly. Thanks for the input guys. You guys, piston ported videos on you tube and a bit of the sticky manual and I went from never putting gas into a lambretta two months ago to complete rebuild.
paul d
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Joined: Thu Jun 30, 2011 10:00 am
Main scooter: T5 172 Tv 240
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Result! Great to see a project finished. You did well!
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