Can a damaged crank be repaired or buy new?

Anything related to Lambrettas... ask tech questions, post helpful info, or just read and learn.
alanscottj
registered user
Posts: 960
Joined: Fri May 23, 2014 6:54 pm
Main scooter: Lambretta GP SS250 Casa
Contact:

When putting a spare engine together recently I managed to damage the crank by tapping the crank into place using a rubber mallet. Big lesson learned :roll: anyway, when I put the mag housing in place the crank turns but then jams up :oops:

So, can I get it repaired? It's a Mec Eur crank and fairly new so it would be nice if I could salvage it :D
Lambretta Series 2 Rat - RB260, SuperTourer, Cyclone 5 gearbox ๐Ÿ˜Ž๐Ÿ‘
User avatar
HxPaul
registered user
Posts: 1110
Joined: Fri Dec 06, 2013 1:58 pm
Main scooter: lambretta Li 150
Location: Halifax,Yorkshire
Contact:

First of all,are you sure that the crank is damaged ? If the oil seal plate hasn't been fit perfectly square you can get these symptoms.If it were my engine I would strip it down and remove the crank and seal plate and check that the plate is seated square.
Chris in Margate
registered user
Posts: 379
Joined: Thu Sep 03, 2009 7:53 pm
Main scooter: Lambretta 1964 225 Special
Contact:

I think you might struggle to damage your crank by persuading it into place with a rubber mallet. As said take it out and inspect it and check the oil seal plate and drive side bearing; they are a highly likely cause of your problem.
alanscottj
registered user
Posts: 960
Joined: Fri May 23, 2014 6:54 pm
Main scooter: Lambretta GP SS250 Casa
Contact:

I LOVE YOU GUYS!!!!

I have just taken the plate off and the crank spins freely with the mag housing in place! Before I removed the plate I had a close look and when I ran my finger around the edge I could feel that one side was ever so slightly higher than the other.

Thank you :D
Lambretta Series 2 Rat - RB260, SuperTourer, Cyclone 5 gearbox ๐Ÿ˜Ž๐Ÿ‘
Minority
registered user
Posts: 673
Joined: Wed Feb 01, 2012 2:00 pm
Main scooter: Li230 S3
Location: Perth, Western Australia
Contact:

Great result!, but I would still look at pulling the crank into place rather than helping it with a mallet.
Chris in Margate
registered user
Posts: 379
Joined: Thu Sep 03, 2009 7:53 pm
Main scooter: Lambretta 1964 225 Special
Contact:

I certainly would never advocate belting it with a mallet but I have always gently tapped and rotated as I inserted and then pulled it in.
hendy
registered user
Posts: 859
Joined: Mon Jul 07, 2014 10:34 am
Main scooter: lambretta li 125
Location: Tyne and Wear
Contact:

I had a similar problem caused by a too-thick halite gasket pushing the plate against the crank web. I resolved by using a new gasket from mb developments which are only 0.7mm thick.

It could also be that your crank is slightly wider than original. If so you can get mag housing gaskets up to 1.5mm thick from mb developments.

I don't work for mb developments :D
User avatar
HxPaul
registered user
Posts: 1110
Joined: Fri Dec 06, 2013 1:58 pm
Main scooter: lambretta Li 150
Location: Halifax,Yorkshire
Contact:

hendy wrote:I had a similar problem caused by a too-thick halite gasket pushing the plate against the crank web. I resolved by using a new gasket from mb developments which are only 0.7mm thick.

It could also be that your crank is slightly wider than original. If so you can get mag housing gaskets up to 1.5mm thick from mb developments.

I don't work for mb developments :D
MEC halite gaskets are bad for this,they seem to be a lot thicker than the cheaper Indian ones.
alanscottj
registered user
Posts: 960
Joined: Fri May 23, 2014 6:54 pm
Main scooter: Lambretta GP SS250 Casa
Contact:

Cheers troops, lesson learned! I notice in Sticky's he writes in bold 'do not hammer' :roll: Managed to get crank in and mag housing and front sprocket all fitted today and it all looks good.

Every day's a school day :D
Lambretta Series 2 Rat - RB260, SuperTourer, Cyclone 5 gearbox ๐Ÿ˜Ž๐Ÿ‘
Lamaddict
registered user
Posts: 854
Joined: Wed Jan 07, 2009 8:35 pm
Contact:

Or use a pin punch at the end of the crank. I love hearing the noise change when the crank is fully home, clunk, clunk, click.
Post Reply Previous topicNext topic
  • Information
  • Who is online

    Users browsing this forum: No registered users and 22 guests