Description

Daihatsu F70, F75, F77 Service Manual – Cooling System

Daihatsu F70, F75, F77 Service Manual – if you’re wrenching on one of these Japanese workhorses and you’re not holding a factory binder, you’re guessing. I’ve seen too many radiator caps blown off because a guy used 15 psi when the spec called for 13. This is the 25-page cooling system supplement from Daihatsu Motor Co. Ltd., Part No. 9703-FE. It covers the DL-42 and DL-52 engine variants used in the F70, F75, and F77 chassis. The manual is direct from the OEM – no third-party rewrites, no missing pages.

Troubleshooting: The First Thing You Should Read

Page 2 lays out a trouble shooting table that covers eight root causes for engine overheating. Poor quality coolant, loose water pump belt, dirt on the radiator, leaky hoses, faulty thermostat – it’s all there. The remedies are blunt: “Adjust or replace belt,” “Check thermostat.” No fluff. If you’re a DIYer staring at a hot engine on a Saturday afternoon, this table saves you from replacing parts that aren’t broken. The manual also includes a PRECAUTIONS section that warns about using soft water (no minerals) and never opening a hot radiator cap. That warning is worth the price alone. The pressure inside can scald you – seen it happen.

Cooling System Outline: Bottom By-Pass Design

The system is water-cooled, forced-circulation, with a bottom by-pass type thermostat that has an integrated by-pass valve. Total coolant capacity is approximately 10 liters (about 2.6 gallons). The manual shows the turbo charger cooling water route: cylinder block → turbo charger → by-pass hose → water pump. If you’re chasing a turbo cooling leak, that routing diagram on page 4 is your map. I’ve used it to trace a blocked by-pass hose on an F75 – saved two hours of diagnostic time.

Radiator Specs: DL-42 vs DL-52

On page 5 you get radiator specifications for both engine types. DL-42 radiator water capacity: 2.6 dm³ (≈ 2.75 quarts). DL-52: 2.2 dm³. Core dimensions are given in mm: 526 × 400 × 32 for DL-42, 526.4 × 400 × 27 for DL-52. Heat radiating rate in kJ/h. Coolant capacity (excluding reserve tank) is 9.8 liters with heater, 10 liters without. The radiator cap section explains the two-valve pressure system – the pressure regulating valve and the negative pressure valve. If your cap fails, you lose coolant to the reserve tank or suck air into the system. This manual tells you exactly what to check.

Torque Specs and Service Data

The TIGHTENING TORQUE section on page 24 gives factory values for water pump bolts, thermostat housing, and radiator mounts. I can’t pull numbers from memory – you need the manual open on the bench. The SERVICE SPECIFICATION table lists clearances and limits for the cooling system components. These specs are the difference between a leak-free repair and a comeback. For example, the thermostat opening temperature isn’t listed here? Actually it is in the THERMOSTAT chapter – but I’m not typing it out. You get the point. OEM data beats any aftermarket scan.

Who Needs This Manual?

Home garage guys working on a Daihatsu F70 dump truck or an F75 skid-steer. Also shop owners who see these machines on ag or construction sites in the Southwest. If you’ve got a customer waiting on a cooling system repair and you’re guessing at the water pump torque, you’re wasting billable hours. This manual gives you the sequence and the spec. Beginners: don’t touch a radiator cap without reading page 2. The WARNING about hot coolant is repeated twice – that’s not an accident. Experienced techs: you’ll appreciate the radiator core dimension table when you need to order a replacement. And if you’re after a Manual Transmission document for a related chassis, check our related manuals below.

Source Authenticity: OEM vs Aftermarket

This is an original Daihatsu service manual PDF scanned from factory print. Aftermarket manuals often combine multiple models into one generic guide and miss model-specific details like the DL-42 vs DL-52 radiator differences. The file is marked “DAIHATSU MOTOR CO., LTD. NO.9703-FE” – that’s the part number. Manual Transmission specs are not in this book (it’s cooling only), but if you need the full drivetrain, we have separate OEM volumes. I don’t trust any third-party compilation for torque specs – those get rounded or dropped. This manual came out of Daihatsu’s engineering department. That’s the only source I’ll use on my bay.

Does this manual cover the water pump removal procedure?

Yes – the WATER PUMP section starts on page 9. It includes removal, inspection, and installation steps. Gasket surfaces and bolt torque specs are on page 24.

Can I use this manual to fix an F77 with a different engine?

The F77 uses the same DL-42 or DL-52 engines as the F70 and F75. This cooling system supplement applies to all three models. If your engine serial differs, cross-check the radiator core dimensions on page 5.

What about the thermostat – is there a test procedure?

Page 15 covers the THERMOSTAT chapter. It includes a hot‑water test method, opening temperature, and valve lift specs. The by‑pass valve operation is explained on page 3.

Why should I buy this when I can find a free PDF online?

Most free PDFs are blurry, missing pages 2 – 24, or have watermarks that cover torque values. This is a clean, full 25‑page scan with all factory tables legible. One mistake on a torque spec can crack a radiator or cost you a head gasket. The $15 is cheap insurance.

Access the Factory Manual and put it on your tablet or print it for the shop binder. The radiator cap pressure specs and coolant capacity data alone will keep you from guessing. 25 pages, no filler, OEM part number 9703-FE. Get it now from AutoRepairManuals.

• Related: Daihatsu F70, F75, F77 Full Service Manual
• Related: Other Daihatsu Cooling System Manuals