Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing MulFab and Petrol Tanks

Thanks Nick,

I presume that the stresses must come from the chassis flex then as the three points of contact are crosshead both sides of the rad and the cross bar between the inner wings or valences as Morgan like to call them. Perhaps a modified top mount might help, I'll have to get my thinking cap on! First though I think is to ascertain what force direction is causing the issue. When I get a chance I will have an investigative look! and report back. Odd though when you think that a plastic and alloy original can last reasonably well yet the forces applied can rip off an aluminium welded bracket from what must be a much stronger item of equipment!

In may 2022 I replace the tank of 2005 PLUS 4. The previous tank was made of aluminium and got leakage in the upper part. It was replace by a stainless tank made by MULFAB. No problem at this date. Welding is fine and gasket provided for fuel pump.

All this concentration on beefing-up the welding and using stronger bobbins are, in effect, attempts to make the radiator a structural part of the chassis. As the chassis is flexible, this approach is likely to bring its own problems. An old-school engineer once explained to me that if a component wants to move - let it - just control its range of movement. Then you do not create any new stresses and avoid component failure. Perhaps a solution could be a larger hole in the top bracket and a bobbin loosely fitted and free to move. I'm interested to hear opinions.

It's surprising how much support and restraint hoses give, they need fitting & fettling properly too

FWIW I spent some time fitting my SiFab rad. There wasn't much clearance to be had each side between inner wings and positioning the cross bar support bracket was critical. Instructions suggested the bracket should face to rear of bar but this simply wouldn't have worked on my car. Another variable was whether the bracket weld to bar was above or below cross bar which varied it's relative height slightly. It took a while as to achieve best choice (lower position) required end to end reversal of cross bar. This allowed no preload strain on bobbin of top mount despite side brackets positioning rad as high as possible (to give best ground clearance), whilst also allowing some clearance with inner wings, something of a balancing act. The care was justified though as 15,000 miles later no chaffing of rad sides seen suggesting it doesn't move that much.