Fuel Sender Fitting

[Trevor]

I am trying to fit GD supplied CAI fuel transmitter into GD supplied tank with GD supplied M5 machine screws.
The tank has a 43 mm diam. hole top left but no fixing boss or threads.
The tank material is not thick enough to tap.
Will a Rivnut ( 6 of them ) give a good enough surface to enable the gasket to seal satisfactorily?
When everything else is welded into the tank this seems a very poor and possibly dangerous arrangement.
Or am I missing something?
Trevor

[Trevor]

OK
I took the plunge and tried drilling & tapping the tank.
Even though 2 threads of engagement. x 6 should be good enough as long as they all hold without stripping.
Just need a M6 left hand tap now to fit turnbuckle for tank straps can anyone help if I send you the bar ?
Trevor

[Glyn_Turner]

Trevor

I have drilled and tapped the tank for M5 bolts, and it seems to be holding without any problems. I have also used Blue Hylomar on the gasket, and fibre washers under the bolt heads to ensure a good seal with no leaks.

Not sure what you mean re the tank straps.

Best regards

Glyn

[oglyoodoo]

I had the same problem and additionally the large hole for the supplied sender was much too small so I had to open out the hole... Just hope I have got all the masses of swarf generated by the hole saw out!
As regards fixings, I didn't think there would be enough meat to tap the tank directly so I decided to make a ring to fit inside the tank. This is made out of a piece of 1/8" stainless 75mm OD and 48mm ID and has 6 tapped M4 holes for the sender and two M3 tapped holes for two M3 CSK screws that are used to secure the ring to inside of the tank. I have cut a sawcut in one place across the ring the idea being that you spring the ring sufficiently to get it over the edge of the Tank hole and then rotate it into the tank, without dropping it in!. It is then secured inside the tank using the two M3 CSK screws. You then have 6 decent M4 tapped holes for the sender. Everything is ready but it has yet to be installed permanently. Another 2 days wasted!!

Denis

[RichardG]

Makes you wonder why the tank doesn't have the threaded holes in the first place...

[Trevor]

Denis
What a proffesional !! That seems an awful lot of work when all it really needs is for GD to use 3mm plate at that point - the stainless is a pig to drill though.
I had to open up the hole as well - across the wide part of sensor only. I used 50 mm wide sticky tape on the inside for each hole to catch some of the bits but will have to flush out anyway.
Now that I have done it I am reasonably happy the 6 screws with two threads will be OK
Glyn
I am using 40 mm wide stainless tank straps and intend using a turnbuckle to pull the two ends together, I can tap a normal M6 thread in a barrel for one end but the left hand thread for the other was my concern. I have since managed to find one of my suppliers who can do it for me.
I just didn`t like the idea of pulling down via various holes in the strap and as I have left over from a previous job excess male tunbuckle parts I thought I would put them to good use.
Thanks for the responce
Trevor

[madjohnny]

Anyone tried these? We use similar things in work and you simply drill the fractionally too small and then the nut is pressed in, but you could probably mount them from the inside of the tank utilising a G clamp to install them.'

Just a thought. Web page attached.

http://www.rivetwise.co.uk/productra...clinchnuts.htm

[craigh]

I used self tappers,they are just as effective and some hylomar

[oglyoodoo]

John

I think those Clinchnuts are pretty good but they rely on the material into which they are installed flowing into the recess under the head. Great for Alloy and other soft metals but it would be pretty difficult to get the stainless to flow without an enormous amount of pressure. Has any body tried it at home with sucess??
The other similar alternative would be a hank bush which you can set in place with a ball from a bearing. These usually have small raised points at the 6 corners to stop them rotating but in hard stainless I have found it hard to make them grip. Perhaps Craigs idea is simplest but I hate self tappers.... I'll do anything to avoid them... Just a personal thing you understand.......

Denis

[Grease Monkey]

Any reason why no ones pushed the rivnut angle? I've a load of M4 inserts and SS bolts that should do the trick nicely (When i eventually get my dials )