1800: Fuel Tank Drain Plug

[Thomas Mitchell]

Good Evening,
This is my first post here so forgive me if I do something out of turn.
I had to drain the fuel tank on a 1968 P1800S that I purchased recently. The drain plug was "stubborn", and I damaged it while removing it. I am trying to locate a replacement with no luck so far. I have attached some pictures of the plug that I removed. There was a small plastic strainer located above it in the fuel tank that dropped out when I removed the plug. Not sure why that was there, but I will put it back with the new plug.
Many thanks for your help.

[c1800]

That’s not the drain plug, it’s to hold the fuel filter in. Check with Brookhouse Volvo for a replacement. They don’t seem to list one, but they may have one used or know where to get one. You might have to reuse the old one. The plastic strainer is the fuel filter , probably best to get a new one and replace it while you’re at it.


https://classicvolvoparts.co.uk/part...Fuel_Injection


Actually there is typically an actual drain plug on the tank, it’s a 1/8” NPT plug with a 1/4 “ square, that you can put a wrench on.

[Thomas Mitchell]

Well that explains a lot. I was searching for the wrong part! Thanks for setting me straight. I pulled that one because it was at the lowest part of the tank. Seemed to make sense at the time.
So does the suction tube for the fuel line attach to the internal filter housing somehow? The filter just slides in up to a stop, but it doesn't seem to be sealed in any way. Just pressed by the plug against the stop in the tank. I've never seen this kind of configuration before (This is my first Volvo)
Any guidance would be appreciated.

[c1800]

Despite yours being a ‘68, your tank might be from a ‘70 and later. Dont think the 68 had that filter arrangement.

Regardless here’s a link to a website full of information.


https://volvo1800pictures.com/wordpress/

[Ron Kwas]

Thomas;

Welcome to this forum!

I too believe that is not the original Tank...the version with the big Plug with mini sump and Pre-filter above was actually originally fitted in a much later injected 1800ES (from I believe '73 [you could check the PNs vs chassis numbers on the gcp.se site if you wanted to research this]...so if you were to inspect that Tank carefully, I expect you'd also find a fuel return fitting on it, now unused and [hopefully!] blocked off) .

Beware! ... the thread on a new replacement Plug you will get from Volvo might/likely will! be off by just a little (11.5TPI vs 11TPI..what it should be! ...and these will be made of steel, so this will be the big hint that it is wrong!), because these are made to fit new replacement Tanks from china, (where they can screw up a junkyard!)....that is why, if it was me, I'd clean up the Plug which was removed, which I know fits, and which in your case doesn't look too terrible from what I see in the pix, and reuse that with some fuel compatible gasket sealer applied.

Here is what Jim Perry ran into (his pix shown with his kind permission):


More here: https://www.sw-em.com/Fuel_Tank_Notes.htm#1800ES_Tank

Cheers from Connecticut!

[Thomas Mitchell]

Thank you very much for the additional information Ron. And please pass on my compliments to Jim Perry for the excellent photographs.
I was able to locate what appears to be an original replacement Volvo brass plug (image attached). Once C1800 informed me of what I should be looking for, the job was much easier.
I had to resort to using a reverse thread extraction tool to remove the original plug. Do you know if there is a specific 11mm tool for installing/removing this? I'd like top avoid butchering another one if at all possible.
Many thanks for your assistance,
Tom M

[Ron Kwas]

Thomas;

I would sacrifice an inexpensive 3/8" socket extension, and grind just enough away to fit.

Cheers

[Thomas Mitchell]

Originally Posted by Ron Kwas

Thomas;

I would sacrifice an inexpensive 3/8" socket extension, and grind just enough away to fit.

Cheers

Well worth the sacrifice.
Thanks again for your help.
Tom M

[Derek UK]

I note a different part number on Jim's and your pictures so I hope you replacement fits OK.