Triumph · 1970–1977The Stag Archive

Servicing / Engine Oil & Filter

Changing the engine oil & filter on a Triumph Stag

By Nathan Devonshire

The single cheapest thing you can do for a Triumph V8 is change its oil often. Clean oil doesn't just keep the bearings alive — it prolongs the timing chains, a known Stag weak point, because the chains and their tensioners rely on good oil pressure and clean oil.

Why, and how often

The Triumph V8 thrives on frequent oil changes. Change the oil and filter every ~3,000 miles or annually, whichever comes first. Most Stags cover far fewer miles than that in a year, so in practice this is an annual job — usually done at the start of the season, or on lay-up.

Steps

  1. 01. Warm the engine, then raise the car

    Warm the engine to operating temperature (warm oil drains better and carries out more contaminants), then stop it. Chock the wheels, raise the front and set on axle stands.

  2. 02. Drain the sump

    Position the drain pan under the sump plug, remove the plug and let it drain fully. Clean the plug and renew its washer.

  3. 03. Renew the spin-on filter

    Unscrew the old spin-on filter (oil will spill — pan ready). Smear clean oil on the new filter's rubber seal and spin it on hand-tight, then about three-quarters of a turn more — no more.

  4. 04. Refit the sump plug

    Refit the sump plug with a sound washer, nipped up firm but not overtightened.

  5. 05. Refill with fresh oil

    Refill with roughly 5 litres of 20W/50 through the rocker/cam-cover filler, then check the dipstick and bring it to the mark. Don't overfill.

  6. 06. Start and leak-check

    Start up — oil pressure should show promptly; if not, STOP and investigate. Check the filter and sump plug for leaks. Re-check the dipstick after it settles.

  7. 07. Dispose and log

    Dispose of the old oil and filter at a recycling centre; log the date and mileage.

Read next

This is a general guide and not a substitute for the official Workshop Manual. Confirm all figures and torques against the manual for your engine and market.