Parts for your 1998 Subaru Forester-Drive belt tensioner

1998 Subaru Forester drive-belt-tensioner — is it actually used?

For the 1998 Subaru Forester (SF, EJ-series engine), a conventional spring-loaded accessory drive-belt tensioner isn’t used. Technical references including the Subaru Factory Service Manual for 1998 Forester (Engine Mechanical — V-belt/drive belt and Air Conditioning — Compressor Belt sections), together with Gates and Dayco application catalogues for this model year, specify two separate accessory belts with manual adjustment: the alternator/power-steering belt is tensioned via the alternator’s adjuster, and the air-conditioning belt is tensioned by an adjustable idler pulley assembly. None of these sources list a standalone automatic accessory-belt tensioner for this vehicle.

That’s why a “drive-belt tensioner” part often isn’t relevant to a 1998 Forester’s accessory drive. If a catalogue shows a tensioner for this year, it’s commonly the timing belt tensioner (inside the timing cover) or the A/C belt’s manual idler assembly being described loosely. Subaru’s late-’90s design stuck with separate belts and screw-adjusters for simplicity, cost, and reliability — a very typical setup before the brand moved to a single serpentine belt with an automatic tensioner on later models.

What owners and techs should do instead under the bonnet:

• Inspect both accessory belts for cracking, glazing, fraying, or rubber dust, replace if worn or noisy.
• Set tension using the alternator adjuster (alt/PS belt) and the A/C idler jackscrew (A/C belt). Avoid over-tightening — that can knock out alternator or power-steering pump bearings.
• Spin and listen to the A/C idler pulley, replace the pulley/bearing if rough or noisy.
• Check the alternator pivot and lock bolts are snug, and that pulleys track true.
• After new belts are fitted, recheck tension after a few hundred kilometres once they bed in.

Technical sources referenced: Subaru Factory Service Manual (1998 Forester, Engine Mechanical — V-belt/Drive Belt, Air Conditioning — Compressor Belt), Subaru EPC/parts diagrams showing the alternator adjuster bracket and A/C idler assembly, and Gates/Dayco accessory drive catalogues noting manual tension for this model year.

Popular questions about 1998 Subaru Forester drive-belt-tensioner

Does a 1998 Forester have a drive-belt tensioner?
No automatic accessory-belt tensioner. The alternator/power-steering belt is tensioned using the alternator’s adjuster hardware, and the A/C belt uses an adjustable idler pulley. Some listings mix this up with the timing belt tensioner, which is a completely different part inside the timing cover.

What do you replace if the belts squeal on a 1998 Forester?
Start with fresh belts if they’re glazed or cracked, then set the tension correctly using the adjusters. If squeal returns, check the A/C idler pulley bearing, alternator pulley alignment, and that the crank pulley/harmonic balancer hasn’t separated. Over-tightening is a common cause of noise and premature bearing wear, so set the tension, run the engine, and recheck.

Is the timing belt tensioner the same as a drive-belt tensioner?
Different systems. The 1998 Forester’s timing belt uses a dedicated hydraulic/mechanical tensioner under the front covers. The accessory “drive” belts for the alternator/PS and A/C are external and manually adjusted, there’s no spring-loaded accessory tensioner on this model.