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MB base gasket issues - please read if you have fitted one
Posted: Tue Mar 30, 2010 7:22 pm
by Knowledge
I have become aware of a number of failures of the new MB base gaskets, leading to serious engine problems. They look like this:
If you have fitted one recently, I would strongly recommend changing it immediately. Under load, the gaskets disintegrate (more like, evapourate) causing leaks that can lead to seizure and piston failure. Scooters fitted with this gasket have lasted less than 200 miles before dying (expensively).
Broady is aware of the problem.
Please don't risk it.
Re: MB base gasket issues - please read if you have fitted o
Posted: Tue Mar 30, 2010 7:33 pm
by Train Driver
ARE THESE ENGINES YOU HAVED WORKED ON AND FOUND THIS OUT OR IS IT SOMEBODY TOLD SOMEBODY ETC,
I PULLED MY RAPIDO APART BECAUSE I LISTEN TO OTHERS WHO IT TURNED OUT WOULDN'T KNOW A RAPIDO IF IT FELL ON THEM

Re: MB base gasket issues - please read if you have fitted o
Posted: Tue Mar 30, 2010 7:54 pm
by Knowledge
I saw this with my own eyes. It was not an engine I dismantled, but it was still "as-removed" and the piston has gone around the rings near the exhaust port, and there was the start of a hole just above. The base gasket had just dissolved. There wasn't even anything to scrap off the face of the barrel/casing interface.
There are 7 known cases of engine failures, and all had the same issues with the base gasket not being there when the engine was split. All used the new MB base gasket.
I don't do scare-mongering, but this seems to be a serious problem.
Re: MB base gasket issues - please read if you have fitted o
Posted: Tue Mar 30, 2010 8:05 pm
by minotaur
i fitted one in the new year, smothered both sides with blue gasket sealant, do we think this may help....
Re: MB base gasket issues - please read if you have fitted o
Posted: Tue Mar 30, 2010 9:05 pm
by soulsurfer
What symptoms would you notice from the base gasket leaking?
Re: MB base gasket issues - please read if you have fitted o
Posted: Tue Mar 30, 2010 9:09 pm
by Ian Hepworth
soulsurfer wrote:What symptoms would you notice from the base gasket leaking?
leaks on the floor, leaks on the base of the cylinder, leaks from the cowls, air leaks, over revving, pinking.
Re: MB base gasket issues - please read if you have fitted o
Posted: Tue Mar 30, 2010 9:14 pm
by Ian Hepworth
This is the story, we have been told by JB and another dealer that some gaskets have failed, we have been onto the manufacturers, on paper (no pun intended) these latest spec gaskets should be perfect.
Since asbestos was banned the gasket manufacturers haven't been able to make anything manmade that is better, or so we're told!
We've fitted a quite a few of these gaskets on engine rebuilds with silicone sealer and have had no problems.
We use the same material in our exhaust gaskets which have proved to be excellent, and can be re-used up to 30 times when dyno testing (that's the exhaust on and off 30 times).
The information came to us a week ago, since then the manufacturers have made a new tool and we are going to now be using a copper and or alloy base gasket (like the T5 ones).
Anyone who's had a problem can have a replacement no problem. We are fully computerised so we know who has had what and when.
Please email
shop@mbdevelopments.co.uk if you need to get hold of us.
PLEASE don't PM me about this. If you want to get in touch about this the email address is as above.
Re: MB base gasket issues - please read if you have fitted o
Posted: Tue Mar 30, 2010 10:00 pm
by Knowledge
Thanks Eden. I knew there had been a thread where disintegrating base gaskets had been mentioned, but I couldn't remember the title. It was Chris who was on the phone to Mark at the very time that JB called Broady.
The symptoms were difficulty in starting and sluggish running, but others were not detected in time and just siezed: one would not come loose and JB had to remove the barrel and piston as one unit once all the studs were removed. As a result, he assumed the base gasket had fallen apart during the rather rough extraction. When the same engine failed again, he was able to take it apart in a more controlled manner and discovered the problem.
Re: MB base gasket issues - please read if you have fitted o
Posted: Tue Mar 30, 2010 10:17 pm
by Train Driver
Like Ian says if you have a problem speak to your supplier/dealer, mark and his staff are very understanding if you need real help just ask direct, i do