The problem in review: Our project vehicle, a late-model work pickup, exhibits overheating during operation. After the truck has been running for a while, the needle on the temperature gauge slowly creeps up toward the red zone. When the truck is in the garage, coolant is found to be slowly leaking out onto garage floor.
With a leak identified, the water pump, radiator and thermostat removed, and the coolant-temp sensor checked, work can now begin on installing the new radiator, water-pump, thermostat, fan-clutch and related accessories. DIY Difficulty Rating for Repair: A thorough check and straightforward repair to the cooling system should take about a day and a half. We give it a difficulty rating of 2 on a 5-point intermediate-level scale. In our demonstration, the repair took about 9 hours over a period of two days. Project time may vary considerably depending on make, model and specific parts being repaired.
Important: Included below are the steps in this automotive procedure as shown in the episode. These steps are general guidelines that are applicable to most vehicles. With any particular vehicle, there may be procedures, specifications, settings, tolerances, components, etc. that are specific to that vehicle. Always consult your vehicle's service manual when undertaking significant automotive repairs. Following are the major steps in the in the coolant system repair as shown in the episode.
Materials:
Vehicle service manual
New radiator and radiator-cap
New water pump
New thermostat
New fan-clutch
Associated gaskets
Replacement hose
Replacement drive belt
Gasket sealant
Autmotive wrenches
Screwdrivers
Razor knife Steps: - Using a razor knife, remove the old gasket and sealer from all mating surfaces where the old water pump was mounted (figure A). Finish up the cleaning using a scrub pad.
- Unfasten and remove the coolant reservoir from the vehicle (figure B) so that it can be cleaned. To clean the reservoir, flush the interior with ammonia.
- Plug the manifold opening with a rag (figure C) to keep debris out during the remainder of the repair work.
- The next step is to install the new thermostat into the housing (figure D) and install the associated gasket. It's critical to ensure that the thermostat is installed in the right direction. Typically, the spring portion is installed toward the engine. Check your service manual to be sure.
- Place some sealant on the thermostat housing (figure E) to seal the thermostat gasket. A thin, even layer of sealant is all that's needed.
- The new water pump has two gaskets. One of them goes inside its backing plate. The backing plate comes dry from the factory. Apply some sealant to the backing plate of the new water pump (figure F).
- Install the first gasket (figure G) and tighten down the backing plate.
- Add some sealant to the outside of the plate (figure H), and install the second gasket.
- The next phase is to install the new fan clutch. Like the thermostat, the fan-clutch must be installed in the proper orientation. A common mistake is to install it backward. Before taking the blade off the old clutch, use a marker to make a mark on the fan indicating the proper positioning of the new clutch (figure I).
- Remove the bolts from the old clutch, and lift the fan off of the old clutch (figure J).
- Place the fan on the new clutch -- with the blade in the proper position -- and bolt it in place (figure K).
- When replacing the fan clutch, make certain that the center-hole (figure L ) is the proper size for installation. If the hole is too large, the fan will wobble, and will cause the new water pump to wear out quickly. In some cases, a spacer is required for exact fit.
- With the fan assembly complete, re-install the thermostat and its housing (figure M). Remember to remove the rag you placed in the opening to keep debris out of the engine.
- Apply sealant on the surface where the water pump mates to the block (figure N).
- Re-position the water pump, and replace the bolts according to their layout in the template devise earlier (figure O).
- With the pump and bolts in their proper positions, tighten the bolts down securely (figure P).
- Next, install the new radiator (figure Q). This new radiator has transmission cooler-line fittings (figure R) so that the radiator can help cool the automatic transmission. It also has clips at the bottom where the fan-shroud attaches.
- With some help from an assistant, carefully lower the radiator into position (figure S) so that it rests on the bottom mounts.
- Tighten the two top bolts to attach the radiator to the truck frame (figure T).
- Install the new lower-radiator hose onto the water pump (figure U), and connect the other end to the radiator.
- Attach the new bypass hose (figure V). In our case, this hose was cut to size to prevent binding.
- Re-install the water-pump pulley.
- Install the fan-shroud next. In this case, the fan and clutch assembly are held loosely inside the shroud as both components are lowered into position together ( figure W).
- With the shroud in place, bolt the assembly back on.
- Next, install the new drive belt (figure X) using the diagram made earlier to ensure proper installation.
- Install the coolant return line (figure Y) using the appropriate size wrench.
- Install the new upper-radiator hose.
- Finally, refill the system with fresh coolant (figure Z).
- Install the new radiator cap.
- With the job complete, start the engine and let it run for a while to check the system. Give the vehicle a road-test, staying close to home until you're certain the newly refurbished system is running OK.
RESOURCES :
The Complete Idiot's Guide to Trouble-Free Car Care
Author: Dan Ramsey
ISBN: 0028635833
Alpha Books
How Cars Work
Author: Tom Newton
ISBN: 0966862309
Publisher: Black Apple Press
Auto Repair for Dummies
Author: Deanna Sclar
ISBN: 0764550896
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