LCGB Forums

Hi all, after some opinions please..

I recently had my TS1 240 engine rebuilt, the engine casing needed a small amount of welding around the head stud holes...sorted..

I had the barrel re honed, head skimmed and the gasket profiled to match perfectly.

New bearings, seals, gaskets etc etc.... ran like a dream, very responsive, sounded fantastic...I was over the moon...

Anyway, on the way to Brid, 35 miles approx., pulled in to a garage for a much needed smoke break and refill of fuel.

roughly 20 mins later, tried to start it...nothing, tried again and a strange squeaking noise is coming from the engine, every time I kick it over the same awful noise and no attempt at firing..

Luckily my wife was kind enough to bring me out a spare scooter and a great weekend was had...I haven't had time to strip the engine yet, so I just wondered if anybody has any ideas what could possibly have happened when standing still in a garage with the engine turned off...

Thanks in advance

Trevor

With respect to the welder, Lambretta crankcases can be a sod to weld.

The alloy comprises zinc to help the casting process, which results in porosity. Then there’s the two stroke oil that will be ingrained.

Then the welding itself can so easily set up stresses that relieve themselves after a bit of heating & cooling.

So sorry, but I’d suspect the squeaking as a 'whistle' due to an air leak....

Thanks for the advice, I will attempt a leak test before I start ripping it down...losing heart a bit now with it, brought the engine as a running lot...all together I think its covered a mere 50 miles (that's being generous) and a total of £2200 .....

don't get too down, could just be the head come loose.
you were going to re torque the head anyway.

fingers crossed...

positive vibes. its what tuned scoots run on.

Even with a slightly porous weld you would still get some fuel and air into the cylinder and there would still be compression, it would at least show some form of life kicking it over. The loose head suggested by Derek (Scooterlam) is the more likely culprit...hopefully..

I would say Head loose with the Squeaking noise , dont get down matey least you got there and enjoyed Brid

The only time I've heard squeaking from a Lambretta the head needed re-torqueing. Most likely culprit after a rebuild.

Could be the stud pulling out of the crankcase as well, so it would be wise to check that.

Thanks guys appreciate the feedback... I will give it a go the weekend and let you know how I get on.

OK I'm going for another root cause. Flywheel parted company with the boss or possibly woodruff key sheared.
These are "awful" squeaking noises.

^... I too wondered about the ignition, woodruff or crank side of things.

Probably not the issue as i'd agree sounds like a loose head issue..........., but just thought i'd throw this in.

We had a squeaking noise coming from the cylinder on a GP this summer (same noise you get with a blown head gasket or loose head). After stripping the cylinder and 'flushing down' the cylinder and head faces and re- 'threebonding' the base gasket and cylinder head it was still squeaking. Eventually we found it to be a bent conrod ??

CHRIS in MARGATE wrote:OK I'm going for another root cause. Flywheel parted company with the boss or possibly woodruff key sheared.
These are "awful" squeaking noises.

I helped strip an engine down in a German garage last year due to symptoms above (not mine) , only to find head , barrel and piston all good. It was indeed the flywheel trying to part company. From now on will always check flywheel first

Lots of things to check, start with the easiest first just getting someone to kick it over while you listen can save loads of time.
personally I would give it two coats of "looking at" before I dropped it and started stripping.

Just a quickie... haven't yet had time to look at the scooter, work is a bit mad, but I haven't given up and I will feedback the results when I eventually get round to it...thanks again.

Ok, well finally checked the engine...full marks to you all that suggested the head bolts. ..
All 4 were finger tight at best with one stud having come completely out of the barrel when tightening.

I've spoken to a friend today who is going to fit a helicoil to hold it in properly...

Thanks again guys really appreciate your help...

Well done for getting it sorted.

I'm going back to crocheting !!

Well done. And especially thanks for following through with feedback.