LCGB Forums

Hi, I'm wondering if the is anyone in the Reigate area who might be able to help my brother get his standard DL150 started.
It is standard except Varitronic and I rebuilt the engine resently.
We have replaced the float and needle in the 22mm dellorto but still seems to be flooding.
It has plenty of fat spark and will fire up only to die as if flooded.
I don't live anywhere near so if the is anyone in he area who could help he would be pleased to make it worth while.
Please pm me a message and I will pass on his number.
Thanks
Tim

I think this was happening to my Lis125.

I started from the spark plug and worked towards the carb.

New plug and check gap, although I was getting a spark with the old plug it was soaked with fuel.

Check the choke is functioning properly and adjusted so it turns off.

Then it's the carb. Check the jets are all clean and are correct

The float and needle are correct and not damaged.

Then the air mixture screw should be I think 1/2 turn out but it needs to be adjusted where it runs best.

Then the throttle needs to be adjusted on the end of the throttle cable so you have a tickover.

Then try starting it. No throttle. It's very tempting to give it some in anger but it will just flood again.


I think your brother needs to try these things himself first and report back.

There are far more informative people on here than me but these are some of suggestions given to me when I had a similar problem.

From my basic knowledge these are things that your going to encounter very often with a Lambretta so I think it's a good idea to have a go at it yourself and get to know your machine.

Good luck
Kris

Serendipity I'm working in Reigate on Monday (near the railway station), should be finished by 5pm and happy to drop in if you PM me an address. No guarantee of success mind Does he have tools?

CambTim wrote:Hi, I'm wondering if the is anyone in the Reigate area who might be able to help my brother get his standard DL150 started.
It is standard except Varitronic and I rebuilt the engine resently.
We have replaced the float and needle in the 22mm dellorto but still seems to be flooding.
It has plenty of fat spark and will fire up only to die as if flooded.
I don't live anywhere near so if the is anyone in he area who could help he would be pleased to make it worth while.
Please pm me a message and I will pass on his number.
Thanks
Tim

sounds like the classic Jetex carb problem. The float is either rubbing against the inside face of carb fuel bowl or the float is binding on the pivot pin .

you need to meticulously check that the float can move freely throughout its range and carefully check that that it cannot rub against the side of the fuel bowl. you'll probably need to carefully dress the edges of the float with some fine wet n dry or jewelers files the same goes for the new needle . make sure it is not rubbing unduly on one side of the bore and preventing the tip of the needle from seating properly

johnnyXS wrote:

CambTim wrote:Hi, I'm wondering if the is anyone in the Reigate area who might be able to help my brother get his standard DL150 started.
It is standard except Varitronic and I rebuilt the engine resently.
We have replaced the float and needle in the 22mm dellorto but still seems to be flooding.
It has plenty of fat spark and will fire up only to die as if flooded.
I don't live anywhere near so if the is anyone in he area who could help he would be pleased to make it worth while.
Please pm me a message and I will pass on his number.
Thanks
Tim

sounds like the classic Jetex carb problem. The float is either rubbing against the inside face of carb fuel bowl or the float is binding on the pivot pin .

you need to meticulously check that the float can move freely throughout its range and carefully check that that it cannot rub against the side of the fuel bowl. you'll probably need to carefully dress the edges of the float with some fine wet n dry or jewelers files the same goes for the new needle . make sure it is not rubbing unduly on one side of the bore and preventing the tip of the needle from seating properly

As Chris says you must not give it the slightest throttle or it will over fuel it with the choke on. That is providing the carb has been set up properly with a slight gap of the throttle slide

It's sounds like he is running the standard SH1/22 Dellorto carb

yes I must have missed that Kris but everything I said still applies for both carbs The jetex is a dellorto clone . There is only a limited range of reasons a float needle valve doesn't shut off . damaged needle tip or valve seat, Detritus on the valve seat, sticking needle , sticking float pivot and float rubbing on the fuel bowl sides and not forgetting the float pivot being too wide for the gap between the pivot pin posts which is what mine suffered from