Bottom Floor Repair

[S2Jay]

The pic below shows a separation on the bottom of the body, just behind the right front wheel opening.
My first question is whether this would be considered a relatively common condition to be expected after 55 years and 40K some odd miles [~ 64K kilos] and xx years storage, or is this an indication of something more serious?

The nest question of course then would be how extensive does the repair need to be.
My unexperienced eye would suggest that I could just mix up some 2-part body filler w/hardener, maybe mix in some chopped strands of mat and be done. Or does this need to be opened up for more serious work?

[mikealdren]

I had exactly the same issue on the floor of the +2 I am rebuilding, probably some idiot jacking the car badly.

It was an easy repair from the inside, I feathered the inside edges of the cracks and added plenty of chopped mat. From the outside, I supported it with a flat piece of 'non stick' plastic which left a pretty good surface on the underside, the resin penetrated the cracks and I may not even refinish it with a new tissue surface as it will be covered in mastic by the time I finish.

[Andy8421]

You may have a combination of problems.

The round-ish hole in the floor looks to be an example of a misplaced jack, the lengthwise split looks more like the result of water in the car causing the ladder frame to rust and expand, splitting the glassfibre. It could of course be a combination of both, or perhaps the floor damage has let water in to rust the ladder frame.

Good luck.

[h20hamelan]

Mrdoow did a premium job, about 7 years ago. He did his from the underside. If you attempt it from the underside, a good vacuum cleaner is your friend. You are not making an airplane so dont need 3hg.

The problem is, now that the glass is exposed to air and moisture. So any open fibres should be removed.
Second, as you have no strength there and let’s face it, 3oz of chop strand below your feet and 80mph
Reinforce with some glass ribs towards the bobbins and chassis.

Remember, strength is in the fibres not the resin. The more resin, the more brittle. So buy a £10 roller and exprel any excess goo, grind away after.

[S2Jay]

Thank you all very much for your responses. Your information, insight and recommendations are very valuable & just the sort of background & info that I need to proceed with a better perspective of the type & extent of the damage.

Having now looked farther back along that seam, it appears that this entire seam may have originally split further back & then been repaired. It may well have suffered from multiple abusive jacking attempts by previous owners. I have no info about how many p/o's there may have been by 1984 when I met this car. I could only speculate that the p/o from whom I obtained it was not a DIY type, whether a "car guy" or not. I only know that the synchro in 2nd was no longer performing its assigned duties and that the car had met an object more solid than itself dead center on the front bumper at some time in its past. There seems to have been only minor damage from this [cracked & repaired bumper], but I begin to question that assumption the farther into the depths of the body I get. In any case, it has always driven & braked well & straight with no odd tire wear issues, so I cannot & do not complain & have always felt that I got a decent & appropriate deal when acquiring this S2 from what appeared to be a geek in a suit atop the parking garage of his office on Wilshire in downtown L.A. But I digress.

Attached is a new pic attempting to show the greater length of the seam in question & how it now appears that there may have been 1 or more repairs attempted. This is in case anyone with a more experienced eye can offer any better interpretation as to the possible extent of the damage & if this would affect the type of repair to be made.

I will have a look from the top side to see how it looks from the inside, and may even try to address it from both sides to strengthen it a bit. My repair may now need to be postponed until ongoing work on the "firewall" [cosmetic only, but I have always considered this to be a relative term with regards to a Lotus with but a thin layer of fiberglass for fire "protection"] & suspension is completed.
Again, thanks to all who have offered input. The quality & amount of expertise offered openly here is always amazing & a modern marvel.

[Andy8421]

Further to my earlier post and to your recent picture, along with your jacking hole, I am afraid the symptoms you have are consistent with a rusting ladder frame. The fact the split continues along the bottom of the sill is a bit of a giveaway. This is more likely if the car has been kept outside for part of its life, and more common in convertibles which are more likely to leak and have soggy carpets - If this is the case, the repair is a bit of a pig of a job. In your case, the floor damage could have been the catalyst.

Have a look here:

https://lotuselan.net/forums/viewtopic.php?t=1979

[S2Jay]

Andy8421

Thanks much for your reply & link to the other post. That is a great description & detailed guide.
I am/will be a bit surprised if the rust is that bad on this car, since I “think” [as opposed to know for sure] that it has always been a Southern California car, at least it has been since 1984 [and even if it were a “So Cal car”, then it could have been kept near the coast & left outside exposed to the highly corrosive salt water atmosphere]. However, I have not really found any signs of significant rust anywhere on the frame & front suspension that I have dismantled & have been cleaning & refreshing [a project long delayed due to other issues not related to the car].

In any case, I now better understand the need to open the sill area, inside & out. Unfortunately that project will need to wait until I have completed the mechanical work part of this rebuild that I am doing now. Thank you much for the assist with this.