My Subaru Brat cranks but won't start. Is it the fuel pump?

Short answer: Spray a little starting fluid or put a splash of gas in the carb. If it fires briefly, it's a fuel problem. With the key on, listen for the pump and check for power at its connector. Owners say the control unit should power it with the key on. Test the pump on the battery. Then check the fuel filter, lines and the carb float level, and make sure the battery and alternator are healthy.

Symptom: The engine cranks normally but won't start, or starts only after fuel is poured into the carburetor.

What to check first

1. Try a small amount of fuel in the carb. If it fires briefly, the problem is fuel delivery.
2. Key on: listen for the pump and test for 12 volts at its connector.
3. Pull the pump and run it straight off the battery.
4. Replace the fuel filter and check lines for clogs or cracks.
5. Check the float level and the throttle linkage, and test the battery and alternator.

Likely causes

1. Fuel pump not getting power. On second-generation Brats, a fuel pump control unit powers the pump with the key on, according to the factory manual an owner quoted. A bad unit or connection means no fuel.
2. Failed fuel pump. The pump can be tested by connecting it straight to the battery.
3. Clogged fuel filter or line. A clogged filter or line can starve the carburetor.
4. Carburetor float or linkage set wrong. The float sets the fuel level in the carb. Set too low, there's too little fuel to start.
5. Weak charging or battery. A weak alternator or battery can leave the pump without enough voltage to push fuel while cranking.

What it usually costs

Owners in these threads didn't post prices. Pumps, filters and hoses are generally inexpensive parts.

Is it safe to keep driving?

Leaking fuel near a hot engine is a fire risk. Fix leaks before driving, and don't pour fuel into the carb with the engine hot or near sparks.

DIY or shop?

Very DIY-friendly: testing power, the pump, filter and lines needs basic tools and a test light.

Recalls, bulletins and complaints in plain words

• Related recall: NHTSA lists 78V181000 for some 1979 Brats: a tube in the fuel vapor system could clog, letting pressure build up in the tank until it bulges and cracks, which could leak fuel. That's a fuel tank issue, not a no-start cause, but worth checking on an early truck. NHTSA's lookup returned no recall data for several later model years, so check your VIN. Check your VIN at nhtsa.gov/recalls. If your car is part of a recall, the dealer fixes it for free.
• Plain words: The complaint count below shows how often owners reported problems that mention these words to NHTSA. A count is not proof of a defect.
• NHTSA complaints: 0 keyword-matched complaints for Subaru Brat 1978–1987 (of 1 unique complaints queried, NHTSA complaints API by model year, queried 2026-10-31; keywords: start, fuel, stall, carb) (NHTSA returned no data for 10 model-year queries). This counts complaints that mention these words. It is not a defect finding.

What owners report

• In Looking for fuel pump information. on Reddit r/subarubrat, a second-generation Brat owner whose pump wasn't pumping asked what tells it to run. Another owner said that per the factory manual, the fuel pump control unit powers the pump whenever the key is on, and suggested pulling the pump to test it on the battery and checking for power at the connector.
• In '86 Subaru BRAT Won't Start. Possible Fuel Issue? on Reddit r/askcarguys, an owner of an '86 Brat with a new Weber carb found it cranked fine but wouldn't fire until a splash of gas went down the carb. Commenters suggested a clogged filter or line, a weak pump not getting enough voltage, the float level and the throttle linkage. The owner said the alternator also seemed to be failing.

Quick tip

Prove it's fuel first, then work back from the carb to the tank. Don't buy a pump until you know it's getting 12 volts.

Vehicle focus: Subaru Brat, 1978-1987.

Safety / mechanic note

Fuel leaks are a fire risk. Verify with a mechanic.