Banjo bolt fitting stripped in aluminum radiator

Hi friends , for my 1990 xjs v12 convertible .
so I managed to strip banjo bolt fitting inside my new alum radiator . Did read Vinnies fix with helicoil etc , but is there anything newer out there.? Hope the longer one from the jag improver might help ,
thanks gina

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@Jeff_Schroeder, you recently addressed this, in a manner.

If you have the luxury of fitting the next size up for whatever it is that needs to be fitted, then why not just tap the stripped hole for the next size up fitting? It’s a better solution than a helicoil.

kind regards

It’s a special hollow banjo bolt. No way to go larger.

You mean “a normal bolt but with two holes drilled in it and a flat inner surface on it’s head because it’s been half parted-off on a lathe”.

It’s not that special. The only bit here that is special is that it wants plating so the inside doesn’t rust.

kind regards

It has to fit the banjo fitting it goes thru. A larger diameter won’t.

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Yes - will post later today, in a time crunch.

Quickly though - I’ve done three of these installs with the Alumiworks “cheap” radiators, and they all have turned out great.

The banjo bolt has to be cut down / no collar needed as it will be too high and both the top and bottom plates need to be cut off the radiator so that the unit sits at factory height underneath the factory core support.

You tap the banjo bolt hole / and now shorter banjo bolt (will post pics later), and use two self-centering bonded washers (the washers with a rubber washer in the center).

Cooler lines are simply a revert back to the early style (more later), and there is no fab needed on the factory shroud to clear the black plastic engine fans with this method. Core support does need its holes enlarged for the bleed and banjo locations although




I went with aluminum from Wizard Cooling. Everything fit. “Plug-n-play”.

My banjo bolts all around my engine and my half moons were sourced from Ron Kelnhofer years ago. But I have purchased items from John_John and all are top quality

The issue with sealing these cheaper radiators is the bung’s mounting surfaces are not always flat. Even if you Dremel or file them to what appears to be true, more times than not factory thin or aftermarket thick copper washers won’t hold it shut.

For the price point though, you get a thicker core that’s very efficient, and takes an afternoon to fit.

The last re-core I did, to 4 rows, on an OEM was just over $800.00 - copper core material prices are insane.

Side note / personal pet peeve, I don’t ever put all electric fans in, always keep the engine driven fan in the V12. Jaguar themselves stuck to an engine driven unit all the way through the 6L as we all know.

From experience, the cycling of the the electric- only fan setups create heat spikes.

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I used Time-Sert to repair stripped threads on my IACV a while ago. Check it out and see if
It can help?

My radiator is from Wizard and fits perfectly.

In my view, the best fix begins with a trip t a welder with TIG skills. Fill the hole. drill, tap and all is well.

i would not rule out a helicol fix.