Delta 11-990 Drill Press Parts: A Measure-Before-You-Order Guide

All Posts setup maintenance Noah Carter Last updated on August 31, 2026

The V-belt on your Delta 11-990 started slipping mid-hole, you opened the belt cover expecting a quick part number lookup, and half the entries came back marked no longer available. That is the reality of Delta 11-990 drill press parts today: this is a discontinued 12 inch bench press, some components are still stocked, and others you will size generically. The machine is worth the effort, because the cast-iron head and tilting table outlast most of what replaced them, and almost every wear item can be matched if you measure before you order.

The Delta 11-990 is a 12 inch bench drill press (Delta’s own manual calls it exactly that), a 115V, 1/3 HP, belt-driven benchtop machine that shipped with a magnetic-base work lamp, a column-mounted utility tray, and a tilting cast-iron table. It runs five speeds from roughly 620 to 3100 RPM on a 1/2 inch capacity chuck, with about 2 to 2.5 inches of quill travel. Delta produced it in more than one type (Type 1 and Type 2, plus an 11-990C variant), and the type stamp matters when you order.

Here is the direct answer: to get the right parts, read the model and type number off the plate, measure the failed component, then order through Delta Machinery or a genuine Delta parts reseller when the item is still stocked, and cross-reference a generic equivalent when it is not. Start where most owners start, the belt and the chuck, then work through the spindle, spring, and switch.

How do you read the model and type number?

Find the specification plate on the head and record the model (11-990) and, critically, the Type number, because Delta parts diagrams split by type. The plate also lists 115V and the amperage draw (about 6.5 A) and the 1/3 HP rating, all of which help confirm you are matching the right switch and motor parts. Genuine Delta parts diagrams for the 11-990 are broken into Type 1 and Type 2 listings on resellers such as eReplacementParts, Fix.com, and Sears PartsDirect, and picking the wrong type is the most common reason a part shows as fitting online but does not seat on the bench. If your plate is worn, the original Delta part number on the head casting or the belt cover (for example the instruction manual is part number 903709) can help pin the vintage.

What belt does the Delta 11-990 take?

It uses a single V-belt between the motor and spindle step pulleys, and Delta listed it under its own part numbers (the parts lists reference belt numbers such as 1310047 and 1343782). Those factory numbers frequently show as no longer available, which is exactly why you measure. Pull the old belt, record the top width and outside length, and match a standard V-belt to those figures. There is a replacement V-belt sold specifically for the 12 inch Delta 11-990 that removes the sizing step: Delta 11-990 replacement V-belt.

Verdict: this direct-fit belt is the first part to buy because it is matched to the 11-990’s pulley centers, so you avoid guessing length against a discontinued factory number. The honest flaw is that a fresh belt will not cure a hard vibration if your step pulleys are already chipped or the spindle bearings are rumbling, so inspect those while the cover is open. Who should skip it: if your press has been retrofitted with an aftermarket link belt that already runs smooth, skip the replacement and just keep the link belt tensioned.

How do you handle the chuck and spindle?

Treat the chuck and the spindle as a matched taper problem, not two random parts. The 11-990 uses a 1/2 inch capacity keyed chuck seated on a Jacobs taper spindle, and owners replacing the spindle have confirmed a JT33 taper works on this machine (one owner fit a WEN 4212B-059 JT33 spindle as a direct cross-reference when the Delta spindle number 134376 proved hard to find). That gives you two clean paths: replace just the chuck with a 1/2 inch JT33 keyed chuck if the jaws are worn, or replace the spindle if runout traces to a bent or pitted shaft. To pull the chuck, lower and lock the quill, then tap the chuck off its taper with a wedge or drift. Compared with the belt, the chuck is a comfort fix rather than a stop-work failure, so prioritize the belt, then address bit slip with a fresh chuck of the same taper.

Which small parts wear out, and where do they come from?

Work through the remaining wear items by measurement and by type-correct diagram:

Quill return spring: the side-mounted coiled spring that lifts the quill. Match by housing size and the roughly 2 to 2.5 inch travel if the Delta part is unavailable.
Step pulleys: measure step diameters, bore, and keyway if a pulley is cracked. Confirm the type before ordering, since Type 1 and Type 2 hardware can differ.
Switch: a standard toggle switch with a safety lock key on many units; match the 115V rating and amperage from the plate.
Chuck key: the original 1/2 inch key (Delta number 1313104) often reads as no longer available, so a standard 1/2 inch drill press chuck key is the simple substitute.
Feed handles and hex jam nuts: commodity threaded hardware; match thread and length.

For sourcing, Delta Machinery and its parts line (reachable through deltamachinery.com and the historical 1-800-223-7278 service line) remain the first stop for genuine parts, backed by eReplacementParts, Fix.com, and Sears PartsDirect diagrams. When an entry reads no longer available on all of them, that is your signal to size the part generically.

Delta 11-990 versus a modern bench press: is it worth keeping?

Keep it. Head to head against a current entry-level bench press, the 11-990 wins on the parts that matter to feel and longevity: a real cast-iron head and table, a smooth quill, and a tilting table with clamp slots. A new machine wins on one thing here, a live parts catalog where everything is in stock. The honest flaw of the Delta is right there in the diagrams: several original numbers, including the factory belt and the original chuck key, show as discontinued, so ownership means measuring and cross-referencing rather than one-click ordering. Who should skip the 11-990: if you refuse to measure a belt or identify a taper and want guaranteed in-stock parts forever, skip it and buy new.

Concrete takeaways:

Record the model and Type number first, because Delta diagrams split by type and the wrong type wastes an order.
Buy a direct-fit 11-990 V-belt, or measure top width and outside length to match a standard V-belt.
The chuck is 1/2 inch on a JT33 Jacobs taper, so a JT33 chuck or a JT33 spindle cross-reference fits.
Start at Delta Machinery and genuine Delta resellers, then size generically for anything marked no longer available.

FAQ

What belt fits the Delta 11-990? A single V-belt sized to the machine’s pulley centers. Delta listed factory numbers (such as 1310047 and 1343782) that often show as discontinued, so measure the old belt’s top width and outside length, or buy the replacement V-belt sold for the 11-990.

What size and taper is the Delta 11-990 chuck? It is a 1/2 inch capacity keyed chuck on a JT33 Jacobs taper. You can replace just the chuck with a matching JT33 unit, or replace the spindle, since a JT33 spindle cross-reference has worked for owners.

How many speeds does the 11-990 have? Five, set by moving a single belt across step pulleys, spanning roughly 620 to 3100 RPM. Confirm against your own inside-cover chart, since printed values can vary slightly by type.

Why do so many 11-990 parts show as no longer available? The machine is discontinued, so Delta and its resellers no longer stock every original component. Common items still turn up, while others (like the original chuck key and factory belt) are frequently gone and must be matched generically.

Where do I buy genuine Delta 11-990 parts? Start with Delta Machinery through deltamachinery.com, then check genuine Delta parts resellers such as eReplacementParts, Fix.com, and Sears PartsDirect, which host the Type 1 and Type 2 diagrams.

Does the Type number really matter when ordering? Yes. Delta splits the 11-990 diagrams into Type 1 and Type 2, and some hardware differs between them, so read the Type off the plate before ordering pulleys, switches, or spindle parts.

Can I still get a manual for setup and parts reference? Yes. Delta’s 12 inch bench drill press instruction manual for the 11-990 (part number 903709) is available as a free download and includes assembly, operation, and an exploded parts view.

References

Delta 11-990 12 inch Bench Drill Press Instruction Manual (Delta Machinery, part no. 903709): https://www.mikestools.com/download/Delta_Drill_Press_Owners_Manuals/Delta_11-990.pdf
Delta 11-990 12 inch Drill Press factory parts list: https://www.mikestools.com/download/Delta-Parts-Lists/11-990-12-Inch-Drill-Press-DP2B.pdf
eReplacementParts, Delta 11-990 OEM parts diagrams: https://www.ereplacementparts.com/models/drill-press/delta/id739782/11-990-type%202/
OSHA, Woodworking eTool, Drill Press: https://www.osha.gov/etools/woodworking/production/machines-tools/drill-press
Canadian Centre for Occupational Health and Safety (CCOHS), Drill Presses: https://www.ccohs.ca/oshanswers/safety_haz/metalworking/drillpresses.html