Parts for your 1987 Suzuki Jimny-Drive belt tensioner

1987 Suzuki Jimny drive-belt-tensioner — what’s actually fitted?

For the 1987 Suzuki Jimny (SJ410/SJ413, also known locally as Sierra/Samurai), a separate spring-loaded drive-belt tensioner isn’t used. Factory documentation shows the engine runs traditional V-belts, and belt tension is set manually by moving the alternator (and, on air‑con models, by adjusting a simple idler). That’s confirmed by the Suzuki SJ410/SJ413 Factory Service Manual (Maintenance and Engine sections), common workshop references like the Haynes Owners Workshop Manual for SJ413/Samurai, and Suzuki’s electronic parts catalogues for the 1987 model year. None of these list a standalone automatic drive-belt tensioner for the alternator/water pump belt on this generation.

Why no tensioner? In this era, Suzuki kept things simple: individual V-belts with manual adjustment. The alternator pivots on a bracket and slides on a slotted arm, once the belt deflection is set, the bolts are tightened. On models fitted with A/C, the compressor belt uses an adjustable idler with a threaded adjuster, but it’s still a manual setup rather than a modern spring-loaded serpentine-belt tensioner. This approach suits the Jimny’s rugged, minimal design, is easy to service with basic tools, and avoids extra moving parts.

What owners should do instead of replacing a “tensioner” is include belt checks in regular servicing. Inspect belt condition and tension, adjust via the alternator bracket (and the A/C idler if fitted), and replace belts that show cracks, fraying, glazing or excessive stretch. After any adjustment or new belt fitment, recheck tension after the first short drive as a fresh belt can bed in and slacken slightly.

• Common symptoms of poor belt tension: cold-start squeal, dim lights at idle (slipping alternator belt), rising temperature in traffic (water pump belt slip), visible belt wear or shiny glazing.
• Quick tips: use a straightedge to check pulley alignment, tighten the alternator pivot and lock bolts firmly, and follow the deflection spec in your workshop manual. On A/C versions, tension the compressor belt with the idler’s adjuster bolt, then lock it down.

FAQs

Does a 1987 Suzuki Jimny have a drive-belt tensioner?
No. The alternator/water pump belt is tensioned by moving the alternator on its slotted bracket. Air‑conditioned models add a simple adjustable idler for the A/C belt, but there’s no spring‑loaded automatic tensioner on these engines according to Suzuki’s SJ410/SJ413 factory manuals and parts catalogues.

How do you adjust the belt on a 1987 Jimny?
Loosen the alternator pivot bolt and the slider/lock bolt, lever the alternator out to set belt deflection per the manual, then tighten the bolts. For A/C belts, adjust the idler using its threaded adjuster until the belt is correctly tensioned, then lock it. Recheck after a short drive.

Can a modern automatic tensioner be retrofitted?
It’s uncommon and usually not worth the hassle. The factory V‑belt system is simple, reliable and easy to set with basic spanners. Unless doing a custom serpentine conversion with aftermarket brackets and pulleys, sticking with the stock manual adjustment is the practical choice.