Jupiter restorations.

[Srenner]

Hello David:

Screws are indeed countersunk with a flat top. Originals are slotted for a straight blade screwdriver. They would have had a large brass finishing washer and not sunk into the floor. Thread is 1/4" x 28 SAE, or American fine and were about 1/2" longer than the sum of the floor and nut. The new front floor joist on 715 uses a modern version of the factory threaded insert.

The factory pressed the inserts into the sheet metal and they can easily be spun. It's a good idea to run a thread chaser or tap through the insert prior to assembly and hold the nut underneath with a spanner or deep socket. If one does spin, it can be brazed into position.

I have not been able to find a finishing washer I like.The stainless ones are much too tall. MGAs came with an even larger steel floor washer.
http://mgaguru.com/mgtech/frame/fr110.htm

Cheers
Scott

[Forumadmin]

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Sorry for all the rallying mods. The extra blocks of wood were to support a toolbox.
The brass hinges were for a wooden cover long since vanished.
The earth strap goes to a battery cut off.
Also see the aluminium sheet which was originally wood. This covers the overdrive. The 1" square tube is an overdrive support and bridges the gap left when the floor support member (the bridge shape) was cut out.

[Andrew Henshall]

The JCL Spare Parts Manual says you need 26 countersunk screws & 26 cup washers, but my car's body frame only has 19 fixing points. See photo of my floor above. They fasteners are definitely 1/4", and I guess they should be Whitworth threads. I can't really tell what thread it is from my body frame because it has been gritblasted & painted, so for the few captive nuts that remain, there is very little thread left, and what's there is full of paint! I'm going to use countersunk screws with cup washers on top of the floor, and flat washers & Nylock nuts underneath the body frame.

Andrew

[Srenner]

Slot-drive 1/4" x 28 SAE is the correct factory screw for the floor. Your 715 is unmolested and very original. Remember, this is just post-war and many Unified fittings were finding their way into British automobiles. Using the MGA again as an example, floor screws are the same thread, but use a posi-drive (Phillips) driver. British cars moved from BSF/Whitworth to Unified to Metric from post-war to the early 70's.
Cheers

[David Kemp]

Thanks Scott I cleaned the threads with a tap & it took very little , one or two were a bit stubborn but most captive nuts were ok. My brother works in a mettle supply & is trying to match some captive nuts for me.
I have cut a floor, but are not quite happy so will make a mk 2 version. After cutting the floor out of ply a friend in the wood industry , suggested I would be better of using Thermolite for the floor as this is stronger & fire retardant. It is certified for bus use, so can't be too bad. Of course this was after I made my floor.

[Forumadmin]

This thread and post from the late Leo shows his battery set up.

[ajackson]

Of slight relevance to this thread, is the following:
viewtopic.php?f=7&t=3788
Andy

[David Kemp]

attached is a picture of my mk 1 floor. Mk 2 will be slightly better.

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[David Kemp]

I have two chassis 715 & 267 , Both have a different front engine support , are both correct or has one been modified?

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[David Kemp]

This is a photo of Javelin exhaust versus modern Alpha , no guess as to which is Jowett.

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[Srenner]

Hey David:

715 is factory standard. The other chassis is a mod to make the joint stronger. At this point in your restoration, it is likely a good idea to add some sort of additional bracing. Be sure to keep it low on the top side of the tube to clear the motor.

Cheers,
Scott

[Forumadmin]

Make sure you use stainless welding rod for the moly tube. I put a 45deg brace across the joint.

[David Kemp]

Could you please post a photo of your braces, Also hoe originally did the floor seal against the drive shat tunnel, Andrew has made an aluminium cover , what did Jowett do? Thicker floor? Mine is made of 1/2 inch ply. Should it be 3/4 ply?

[David Kemp]

these are the before pictures of parts I have soaked in molasses for two weeks. The molasses works brilliantly and is cheap $1 per litre from a pet food supply store.
Probably should have pulled them out of the mixture after it stop reacting approx 10 days. As leaving it too long just coats it in a varnish.

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[David Kemp]

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