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This page can help the "DO IT YOURSELF" car builder avoid common mistakes, making things easier and less frustrating. This page will continue to grow as we get time and information to add to it, so check back periodically. Send us your tips that might help others in the garage or the dunes. To send in a tip, click here.
HOT TIPS Radiator line connections, 101 There is a right way and a wrong way to connect radiator lines. Here are the basics: 1. Always place your radiator as vertical as possible, in the best location, oriented to get maximum airflow while moving. If possible, avoid depending solely on electric fans to do your cooling. Try to mount the radiator so it can get a straight shot breeze of air through the radiator as you drive, assuming your car setup will allow this. 2. Radiator fans need high current relays to turn them on and off as your engine management system dictates as the engine warms up. Almost all relays have a tiny pinhole in the bottom as a breather so condensation doesn't build up and rust things when you're in humid climates. In the desert you don't have to deal with humidity, so this hole should be sealed tight so dust and sand cannot enter the contact area. The same is true for your fuel pump relay. If you experience a fan that's non-operational, or a fuel pump that won't run, and you haven't filled these breather holes, just knock the relay with a wrench to shake out the dirt in the contacts. When you get home, replace the relay and fill the breather hole this time! 3. Assuming you mount your radiator
vertical like it's suppose to be, the top water connection is specifically to RETURN coolant to the radiator
from the motor. The top radiator hose
connects to the coolant exit on your motor, located on the top of a
Subaru motor, and typically on the top of the motor all other motors. The
bottom radiator hose connection is specifically to PROVIDE coolant to the
water pump on the motor, located on the bottom of a Subaru motor, near the area where
the dip stick goes into the oil pan on EJ20 and EJ25 motors. An easy way
to remember how to connect the radiator hoses to a Subaru motor is.... 4. When routing the coolant lines from the radiator to the motor, it's OK to route the lines left and right to get to where you need to go. But avoid routing the lines up and down with dips and rises to make your connections. The lines should have a gradual and consistent slope from the radiator to your motor. If you don't follow these simple guidelines to connect radiator hoses your car can be very temperamental when it loses the least amount of coolant. Air gaps in the top of the radiator manifold can promote the introduction of air into the cooling jacket of the motor. When these air bubbles arrive in the super-hot head/barrel area they can rapidly expand and create micro-bursts of pressure in the cooling system, potentially blowing up your radiator capillaries like a balloon, eventually leaking. To prevent air gaps and setup a radiator system for the best efficiency, here are two diagrams below that gives you the basics of what a sandrail needs. Using a burp tank setup helps prevent air entering your system and it allows the coolant to expand and contract in volume as the motor heats up and cools down. The first diagram shows a pressurized burp tank setup. These systems typically have no filler cap on the radiator, you add coolant through the burp tank filler cap. When you initially fill the system from the burp tank, the coolant enters the engine via gravity through the hose that's connected the heater return connection of the Subaru motor. Since sandrails don't have heaters, this connection works great to fill the motor via gravity. Air escapes through the Air/Water Bleed hose on the radiator as the coolant pushes it out of the motor. When filling the system, as coolant fills the motor with coolant you will see the burb tank level start to rise. When the burb tank level is even with the top of the radiator, start up the motor and bring the motor up to full temp, about 180 to 200F. As the water heats up the excess coolant will expand and escape through the overflow tube. The remaining fluid will be the correct amount of coolant for the system. After the motor cools down overnight, take a note about where the coolant level settles inside the burp tank, viewed through the filler cap. Some folks will mark that level with a felt marker on the side of the burp tank so they can remember the "normal level" when cold. That will tell you when to add coolant, and you will also know when you've got a leak, or maybe when the motor is consuming coolant (bad headgasket). For new motors it's a good idea to check the level on the first few weekend trips, when cold, to insure it's at the correct level. Generally speaking the burp tank coolant level should settle down to about 1/2 to 2/3 full when cold.
The setup below is an example of an UN-pressurized burp tank setup, which is more conventional. It's important to know this setup requires: 1. In this setup, if you run a thermostat (not recommended for sandrails) in your engine you must connect the engine water heater connection (located on the thermostat housing) to the water crossover tube on top of the motor. As the engine warms up this provides hot water to the thermostat, triggering the thermostat to open. 2. If you don't run a thermostat (recommended) you can block of the water heater connection, located on the thermostat housing. To remove the thermostat you'll need a substitute thermostat ring to hold the thermostat gasket (washer is available from Outfront), which prevents the thermostat housing cover from leaking.
The above setup with an un-pressurized burp tank allows more flexibility in locating the mounting place for the burp tank. Sometimes the burp tank mounting placement on the chassis is a problem. If you have little choice on mounting your burb tank this setup may be more desirable. This arrangement requires a filler neck on the radiator to fill the system with coolant. This arrangement requires that you always fill the radiator from the RADIATOR filler cap, not the burp tank as described for a pressurized setup. If you ever load your Subaru powered sandcar into the trailer and tow the trailer a distance, then find out your car won't start, you're likely the victim of a slipped timing belt. What likely happened was your tow straps were not tight enough, and the car rolled backwards, turning your motor over in reverse. This can make your motor skip a cog on the timing belt. To prevent this situation you need to know this crucial tidbit of info. ALWAYS trailer your car in neutral. If your straps come loose and the car rolls backward while in gear, being in neutral prevents the possibility of de-tensioning of the cam belt, so much so that the crank can slip a cog or two, maybe three. When the crank becomes out of time with your cams, your hosed. The car can't start, no worky! The worse part is that you have a high probability of bending valves if you slip a cog when cranking the motor, assuming you're using stock Subaru pistons. If you're using Outfront's "non-interference" pistons you won't bend valves in this scenario in most cases. But it still won't start until you re-time your cam and crank properly. If you don't know how to re-time your crank and cam yourself, this is a good thing to learn. This knowledge can save your weekend. SOHC setups are very easy, DOHC setups are a little more intricate, but not tough to learn. It's also nice if you have an Outfront exhaust setup so all this can be done without removing your exhaust, turbo, and intercooler. CV maintenance is an important part to prevent ruining a perfectly good weekend. It's recommended you inspect your CV's every 15th trip to the dunes, or at least once every 2yrs, whichever comes first. Inspection requires disassembly of the CV and wiping off all the grease so you can see the metal surfaces for wear, pits, or cracks. If it's your first time to inspect a CV it's recommended you consult with someone "in the know" so you can learn what you're looking for. Most of the reputable parts houses who sell CV's can help. Do not start this job without latex gloves to keep the grease off your hands, it's nasty stuff. Also, make sure you keep your axles and CV's off the ground and on a workbench so all the grease is isolated to the bench, and off your shoes. If you want to keep peace with the wife, tracking grease inside the house on the rug won't help. Also, before you pull your axles off, mark the the end of the axle for orientation, such as LO for "Left Outer" and RO for "Right Outer". For insurance you can also mark the other end of the axles LI for "Left Inner" and RI in case the other markings are rubbed off accidentally (it happens). This is to insure you reinstall the axles the same orientation so the twist of the axle continues twisting the axles in the same direction. After you have disassembled the CV's you need to clean them up as best possible. Using solvent, lacquer thinner, or gasoline will suffice, take your pick. Make sure each part is very clean, then inspect them for pits, cracks, and excessive wear. Again, your local parts house can help you determine what's excessive. It's best to keep all the parts for each CV together, separated from the other CVs, not mixing up the parts from all 4 CV's. When your CV's are ready to put together you need to assemble them in a certain order. There is a wrong way to assemble them. Here are some tips: 1. The cage opening is slightly larger on one side. The large side is the side you install the star gear from, it barely fits. 2. Before you put the ball bearings in, put the star in the outer case. Then insert the ball bearings in by twisting the star gear within the outer case to expose the bearing race opening. If the star doesn't move freely after you install each ball bearing, you've assembled it wrong. If this happens you likely have the star clocked one cog off. Take the balls out and reclock the star, moving the star one cog either direction. 3. When you have all the ball bearings installed and each CV matches these pictures, the next step is packing the CVs with grease. Before getting started with the grease, cut 1/2" X1/2" squares of duct tape, you'll need 24 of them for a set of 930's. Put a duct patch over each hole in the outer case, both sides. This will keep all the grease out of the holes, very important so the loc-tite on the bolts aren't compromised with grease upon installation. 4. Next, put on LATEX GLOVES. This can be a messy job for the novice. Keeping the new CV grease in the CV joint and off your hands is next to impossible, even for an experienced mechanic. Take your time, don't rush it. 5. Use a grease needle adapter, it makes the job of inserting the grease a lot easier. You can buy them for about $15 to $20 at Napa, Autozone, even Harbor Freight. If you have trouble with the zerk fitting coming out of your grease gun fitting while in use, duct tape can aid to prevent that from happening, or remove the zerk and screw the needle adapter onto the end of the grease-gun hose. 6. A common grease to use is Swepco, costs about $8/tube. Another common grease to use is Belray, which is about $22/tube. You can usually pack 2 CV's with one tube of grease. Many of the racers use a mix of 75% Swepco and 25% Belray. Just put the Swepco in first then put in the Belray if you want to use a mix. There's no need to hand mix the two greases buy hand, unless you want to get really messy. The CV will mix it up on the first ride. 7. If your job is a first time assembly, make sure the CV bolts are the right length for the transaxle side. If they are too long they can carve up the transaxle case, that's a bad thing. Sometimes using the wrong washers on the CV bolts (or forgetting the washers) will let too much bolt be exposed on the back side of the CV flange, which touches the transaxle. 8. If your job is a reassembly of worn CV's, make sure your bolts are clean and dry so the loc-tite will work best. Use carburetor dip to clean the used bolts, or aerosol can of brake cleaner, then hose them off and blow dry with air hose (if you're in a hurry). 9. After packing the grease in the CV, carefully put the CV's on the axle and put on the axle clips. When you've got both CV's on the axle and you're ready to install it on the car, remove the duct tape squares. Carefully reinstall the axles, slowly. If you have a buddy it helps if he holds one end while you install the other end. Be careful the CV's don't get twisted at too high of an angle during reinstallation. If they do you could lose a ball bearing, which is not good after you remove the duct tape patches. Install one bolt at 12 o'clock on each end first without Loc-tite by fingers, this will hold the axle in place so you can take your time with each bolt as you apply Loc-tite to each bolt as you go. Don't forget to remove the 12 o'clock bolts at the end and reinstall with Loc-tite. 10. Always use Loc-tite on each bolt. The "red" grade of Loc-tite is too strong, we don't recommend using it. The 'blue" grade of Loc-tite is best for most duning enthusiasts. "Blue" makes it easier to disassemble for inspections. The red type loc-tite is almost impossible to remove later, so avoid the red type. 11. Torque the bolts to 45ft lbs. When you get both CV's done on the first axle, test it by spinning the axle while in neutral, just to make sure the bolts clearances for the transaxle is acceptable. If the axle doesn't spin freely you should check the bolt lengths, or the washer thickness for each bolt. How do you insure your axles are long enough, or too long? Lift your car so the rear swing-arms are at full droop. Grab the axle and move it left and right, toward the trans, then toward the wheel. If you have at least a 1/4" of movement your axles are long enough. Then raise the swing-arm so the axle stub is at the same level at the transaxle flange, which is usually the shortest distance (you may need to remove your shocks to do this) between the wheel stub and trans. Then grab the axle and move it left and right again. If you have at lease 1/4" of play, your axle isn't too long. It's important to check the side-to-side play at the shortest distance between the swingarm flange and transaxle flange. Sometimes this can be slightly above or below the axle being level, so thoroughly check it for play through this "level range", insuring there is at least 1/4" of play throughout the range of swingarm travel. It's important that a large negative battery cable go to the transaxle or
engine-- not the chassis. Many buggy builders connect a battery ground cable
to the chassis only and rely on the engine/tranny making a ground to the chassis.
This is a bad idea, real bad. If the assy loses ground connection due to
powder coat insulation,
or bolts coming loose, you can damage other items like an ecu or throttle cable
because they are the only grounds left during high current demands (like
starting the engine). It's best to run a 0 gauge cable from the battery negative
to the transaxle to support the starter, and an additional smaller 8 gauge ground cable
from the battery negative to the chassis for the rest of the car as a precaution to bad
engine and/or trans ground connections over time. |
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