Sagging bottom

[RichC]

I'm in Discovery mode currently with my new acquisition 50 /734 and uncovered a 4" crack in GRP below battery running fore and aft alongside the chassis mounting plate. From underneath the bootfloor is seen to sag aft of the mounting plate and you can pick up the rear of the car quite a bit. Has anyone witnessed this before & if so ,what is the common remedy?
My thoughts run to fabricating a larger mounting plate before I tackle the rather major GRP repair... is that necessary & if so how big?? or is it just that at some time in the past some fat b****** has sat on the OSR wing?
I think the resultant flexing would be quite alarming on the bumpy roads of GB today if left alone.
I remember dealing with similar problems on the GRP body of a clan crusader I rebuilt years ago so am comfortable with the idea of getting the right thickness of GRP for the balance of strength and flexibility, if that's all that is commonly employed .
Cheers,
RichC the Newby (for now)

[gerrym]

RichC, any chance of a photo of the fibreglass split. By chassis mounting plate, do you mean the rear extension of the chassis horizontal section (aft the curved tubes)?

I think the chassis "plate" is more than adequate here. Most probably all that is needed is a competent repair of the GRP. Both to restore the original shape (ie support the existing sagging) and to restore strength. Is it possible to ascertain how the damage originated. My boot floor damage was almost certainly caused by PO, reversing exhaust pipe into external obstruction, with the silencer mounts taking the damage.

Regards

Gerry

[Jason1]

Hi Rich

Holes in boot floors seem common due to broken donuts causing the shaft to fly through the boot floor.

See elan-plus-f13/boot-floor-fibreglass-repairs-pop-rivets-t16428.html

for some impressive repairs.

Jason

[RichC]

Hi jason,
thanks for the link to the scary stuff. I feel empowered to tackle it properly now. ( well maybe not RIGHT now , but sometime in the summer ...
cheers, & thanks again for your help.

p.s. I'm pretty sure you may have heard of the old trick for unseizing clutchplates , but just in case, I've found that selecting 4th gear , depressing clutch pedal and turning over ignition has worked for me. You'll hear the bang as the starter motor clears the plate from flywheel...

Rich C

[Jason1]

Hi Rich

p.s. I'm pretty sure you may have heard of the old trick for unseizing clutchplates , but just in case, I've found that selecting 4th gear , depressing clutch pedal and turning over ignition has worked for me. You'll hear the bang as the starter motor clears the plate from flywheel...

Yes tried that at the weekend but with limited spare it is a bit hairy.

Jason

[RichC]

The good weather over the bank holiday allowed me to get down to it!
first picture shows the splits from beneath

before- note the bootfloor sagging aft and to both sides of chassis mounting, especisally on RHS

main split seen more clearly after a dose of sanding - continues up the back of the bootwell- likely to be result of past rotoflex failure. small hole below and to right

after a liberal application of several sheets of fibreglass matting and lots of resin

And with all the cosmetic surgery pictures I'll show you the sagging bottom BEFORE and AFTER

notice the sagging boot obscures chassis plate . the exhaust pipe sags too and you can see RH flange of chassis

P4300003.JPG (30.57 KiB) Viewed 1128 times

Before fibreglass repairs commenced , i put a jack under a 4x2 joist running diagonally across from under RH wing floorpan seam across the exhaust box to middle of rear valance seam and jacked the back up a good 5 inches I reckon, and watched as the sagging bottom was raised to its original position. Afterwards, I released the jack slowly and to my relief , it stayed there! You can see the exhaust sits higher & closer to the chassis plate ( blocking view of RH flange now) . and the sagging bottom has disappeared!

likewise from the other side

and after treatment

P5060003.JPG (52.46 KiB) Viewed 1129 times

.

RichC