Connecting Rod Breakage Explained

Transcription

1 August 2009 Helping you fix it right the first time - every time Connecting Rod Breakage Explained Currently Applies To: General Information EDITOR S NOTE: This article replaces Why Do Connecting Rods Break? in the November 05 issue of ServiceNews Connecting rods are specifically made to withstand brutal forces and temperatures. Yet, every once in a while, they bend or break and wind up as cool conversation pieces for a coffee table or desk. Why? For a connecting rod to bend or break, either the engine must hydrolock or the connecting rod bearings must fail. When troubleshooting a bent or broken connecting rod, here s some food for thought: Hydrolocking is the number one culprit for connecting rod breakage. It happens when the volume of liquid that s entering the combustion chamber (water or fuel) exceeds the chamber s volume. Since liquids don t compress, the piston stops before it reaches top dead center (TDC). But the crankshaft keeps on turning from inertia, so as a result, the connecting rod bends and gets shorter. With each compression and power stroke, that rod flexes. You won t always notice anything wrong, until it finally gives out and breaks from metal fatigue. Hydrolocking can happen if you re driving through deep, standing water that s above the level of the air intake, or you re driving fast enough through it to splash water over the hood. It can also happen if you re driving through deep, standing water and someone driving the other way splashes water over your hood. Vehicles with cold air intake systems are especially vulnerable to hydrolocking since the air filter is mounted down low to draw air from the bottom of the engine compartment or the front of the radiator. Water sucked into the air filter gets sucked right into the engine. If you suspect hydrolocking, check to see if the air cleaner element and air cleaner housing are wet. Often times, there ll be dirt or mud from the road deposited on the inlet side of the air cleaner element or even in the intake air duct. Keep in mind, hydrolocking isn t a manufacturing defect so it s not covered by warranty. If hydrolocking is the problem, your service customer needs to contact his or her insurance provider; it s considered accidental damage. Although it s rare, sometimes a bad ECM/PCM or fuel injector can cause too much fuel to enter a cylinder, causing hydrolocking and resulting in a bent rod. Before that happens, though, there are usually some sort of driveability problems that crop up and remain after the engine is fixed. (cont d)

2 Connectiong Rod Breakage Explained... (cont d) A bent connecting rod might not show any symptoms until it actually breaks. But a sure-fire indicator is the carbon line it leaves on the cylinder wall. A normal connecting rod leaves a carbon line that s about 6 mm deep. A bent connecting rod, since it s shorter, leaves a second carbon line that s even deeper. CARBON LINE (6 mm DEEP) SECOND CARBON LINE (DEEPER THAN 6 mm) Connecting rod bearings fail for lots of reasons. To find out what really caused a rod bearing failure, you ve got to take apart all of the rod bearings and main bearings and compare them side by side. If all or most of the bearings and journals show similar damage (scoring, exposed copper, or heat discoloration), the likely culprit is oil starvation, poor maintenance, customer abuse, or running the engine with an aftermarket power booster (a nitrous oxide setup, supercharger, or turbocharger). If just the bearing or journal for the failed rod looks bad, but all the other ones look good (no scoring, exposed copper, or heat discoloration) and the crankshaft journals are smooth with no heat discoloration, then that particular bearing/clearance would be suspect. S/M Fix: Stall Speed Information Currently Applies To: Fit You need to tweak the Specifications section and Automatic Transmission section of the Fit S/M. The stall speed info is wrong. Make these changes to your copies of the S/M; they ve already been made in ISIS. Page 2-9: Change the torque converter stall speed info to read like this: Item Measurement Qualification Standard or New Service Limit Torque Converter Stall speed Check with vehicle on level ground 2,200 rpm 2,050 2,350 rpm Page , step 8: Change the stall speed info to read like this: Stall Speed rpm Specification: 2,200 rpm Service Limit: 2,050-2,350 rpm 2 of 8 August 2009

3 Got VSA DTC(s)? Reseat the VSA Modulator-Control Unit Connector Currently Applies To: 09 Odyssey Got a vehicle in your shop with any of these DTCs? VSA DTC 27 (steering angle sensor) VSA DTC 84 (VSA sensor neutral position) VSA DTC 86 (F-CAN communication) VSA DTC 104 (sensor cluster) DTC U0122 [F-CAN malfunction (PCM-VSA modulator-control unit)] Before you get into heavy troubleshooting, try reseating the VSA modulator-control unit 47P connector. Then clear the DTC(s). To reseat the connector, push down on the orange lever; the connector unplugs itself. Then align the connector to the unit, and pull up on the orange lever until it clicks into place. It s that easy. CLICK A poor connection can cause these and other DTCs, and simply reseating the connector and clearing the DTC(s) will often do the trick. But if it doesn t... then refer to the applicable DTC troubleshooting in the 09 Odyssey S/M or ISIS. August of 8

4 Rearview Camera, Seat Heaters Don t Work? Check No. 30 (10 A) Fuse Currently Applies To: Odyssey If you re working on a vehicle because the rear climate control panel, the rearview camera, the seat heaters, and the outside temperature indicator in the MID or information display aren t working, check for a blown No. 30 (10 A) fuse in the driver s under-dash fuse/relay box. That fuse controls those circuits. Repair the harness if needed, and wrap it with a piece of EPT foam for added protection. Reinstall the control panel, and replace the No. 30 fuse. If everything now works right, you re done with this repair. If the No. 30 fuse was OK or you ve still got problems, then continue with normal system troubleshooting. DRIVER S UNDERDASH FUSE/RELAY BOX If the No. 30 fuse is blown, pry out the rear climate control panel above the driver s B-pillar and look for cut wires in the harness about 1 to 2 inches from the end of the green 5P connector. The metal bracket behind the control panel has sharp edges that can cut through the harness sheath and into the wires. SHARP METAL EDGES No. 30 (10 A) FUSE Wrap harness with EPT foam. S/M Fix: Heated Windshield Wiper Area Function Test Currently Applies To: Ridgeline The Heated Windshield Wiper Area Function Test in the applicable Ridgeline S/M needs a bit of tweaking. It doesn t tell you what outside temperature turns the heated windshield wiper area on and off. Change the note at the beginning of the test to read like this NOTE: The system only works when the outside ambient temperature is below 39 F (4 C), and turns off when the ambient temperature is above 45 F (7 C). Before testing, check the No. 14 (20 A) fuse in the under-hood fuse/relay box, No. 30 (10 A) fuse in the under-dash fuse/relay box, and the heated windshield wiper area relay in the under-hood fuse/relay box. Mark up your copies of the S/M to reflect this change. It s already been made for 09 models in ISIS and will be included for earlier models as well. REAR CLIMATE CONTROL PANEL 4 of 8 August 2009

5 ETM Fix: Heated Windshield Wiper Area Defogger Currently Applies To: Ridgeline You need to do a bit of tweaking to the Ridgeline ETM. The Heated Windshield Wiper Area Defogger section doesn t mention at what outside temperature the defogger turns on and off. Mark up your copies of the ETM to look like this: Page 64 Add the text shown in red. S/M Fix: DTC P0135, P0141 System Troubleshooting Currently Applies To: Accord V6 Page of the Accord V6 Supplement has a couple of errors in the system troubleshooting for DTC P0135 (primary HO2S [sensor 1] heater circuit malfunction) and DTC P0141 (secondary HO2S [sensor 2] heater circuit malfunction). In step 3, the question Is DTC P0135 or P0141 indicated? should read Is the fuse OK? In step 7, the NO response to the question Is there continuity? should read Go to step 8. Mark up your copies of the S/M to reflect these changes. They ve already been made in ISIS. Pages 64-1 and 64-2 Add the same text on these pages. The 09 Ridgeline ETM includes these changes. They ve also been made to the Ridgeline ETM in ISIS, and we ll be including them for earliermodel ETMs as well. New HDS Software Release: Version Currently Applies To: General Information During the week of August 3, every Honda dealer was shipped a new HDS software release on CD. This CD has a white label with lime green lettering that reads HDS VER , and it s dated August Your system administrator should have this software already loaded onto the master server. Here s the lowdown on : It provides system coverage for the 10 Accord, Civic, CR-V, Element, Fit, and Ridgeline. It supports S/B , Product Update: Lock-Up Clutch Judders Between MPH for the Odyssey. IMPORTANT: Make sure this software gets installed on all HDS devices right away. Your dealership will be considered out of compliance if it s not done within 3 business days of receipt. Also, any repairs done with out-of-date HDS software might not be covered under warranty. August of 8

6 Chain Case Cover Oil Leak? Here s the Fix! Currently Applies To: Accord, CRV, Element. Some chain case covers did not seal well against the chain case from the factory, causing some leakage. If you have a service customer s vehicle with a leak in this area, the fix is simple: Remove the chain case cover, and clean off any oil and sealant, making sure both contact surfaces are completely dry. Any old material or oil left behind will prevent proper sealing. Apply a new bead of Honda Bond (P/N , H/C ) according to the instructions, and reinstall the chain case cover to the proper torque specs (12 N m, 8.7 lb-ft). To avoid a repeat of this issue, proper cure time is essential, so be sure to wait at least 30 minutes before you add any oil, and at least 3 hours before starting the engine. VIEW THROUGH RIGHT FRONT WHEEL WELL CHAIN CASE COVER DRIVESHAFT ASN (0908) 6 of 8 August 2009

7 Dead Battery? Check for Excessive Parasitic Draw Currently Applies To: Ridgeline Got a vehicle in your shop with a dead battery? Before you consider battery replacement, first check for excessive parasitic draw. A parasitic draw of 25 ma or less is considered normal. If you re not sure how to do this, take a look at Excessive Parasitic Draw? Check If the B-CAN System Is Awake in the July 08 issue of ServiceNews. If you re reading a normal parasitic draw, troubleshoot the charging system. If you re reading an excessive parasitic draw, hook up the HDS and select BODY ELECTRICAL from the System Selection Menu, Security from the Mode Menu, and then Data List from the Security Mode Menu. Scroll down the list to In-bed Trunk Lid Knob Switch, and check the switch position. - If the switch position is ON, check to see if the lip of the rubber cover for the In-Bed Trunk lid handle switch is tucked into the lid opening; this can cause the switch to stay on, and draw enough current to discharge the battery. If the lip is tucked, use a pocket screwdriver to release it, then recheck the parasitic draw. If the draw drops to normal, you re done with this repair. If the lip was OK to begin with or the draw stays the same, then continue with normal system troubleshooting. IN-BED TRUNK LID HANDLE SWITCH RUBBER COVER LIP - If the switch position is OFF, pull the No. 7 (7.5 A) fuse from the under-hood fuse/relay box and recheck the parasitic draw. If the draw drops to normal, replace the under-hood fuse/relay box and check the draw again. If the draw is now normal, you re done with this repair. If the draw stays the same or it never dropped to normal when you pulled the No. 7 fuse, then continue with normal system troubleshooting. UNDER-HOOD FUSE/RELAY BOX NO. 7 (7.5 A) FUSE August of 8

8 Trouble Resetting That Power Window Control Unit? Check This Out Currently Applies To: Accord, Civic and Civic Hybrid, CR-V, 09 Fit, 10 Insight, Odyssey, Pilot, and Ridgeline Having trouble manually resetting a power window control unit? Here s a procedure that we ve found works every time. IMPORTANT: You must do this manual reset from the power window switch of the affected window. For example: If you re resetting the driver s power window control unit, you must do it from the power window master switch. And if you re resetting the front passenger s power window control unit, you must do it from the front passenger s power window switch. 1. Turn the ignition switch to ON (II). 2. Lower the window all the way down with the power window switch. 3. Open the driver s or front passenger s door (it doesn t matter which). 4. Do each bullet in this step within 5 seconds of each other. Do this entire step a total of four times. This step clears the control unit s memory. Turn the ignition switch to LOCK (0). Push down and hold the power window switch. Turn the ignition switch to ON (II). Release the power window switch. 5. Make sure the auto-up feature doesn t work. If it still works, redo step 4, paying close attention to the 5 second time limit for each bullet. NOTE: Steps 6 and 7 teach the control unit the window settings needed for the auto-up/down feature. Keep in mind, if you re resetting the front passenger s power window control unit, you can t work the front passenger s window from the power window master switch until that control unit has learned the window settings. 6. Lower the window all the way down with the power window switch. 7. Pull up and hold the power window switch until the window goes all the way up, then keep holding the switch for 1 second. 8. Make sure the auto-up/down feature works right by lowering and raising the window with the power window switch. If it doesn t work right, repeat this manual reset several times, paying close attention to the 5 second time limit for each bullet in step 4. If that still doesn t work, then troubleshoot the power window circuit. Youth Educational Systems 2009 American Honda Motor Co., Inc. - All Rights Reserved. Published by AHM Parts and Service Communications, 1919 Torrance Blvd., Torrance, CA All suggestions become the property of American Honda Motor Co., Inc.; sending a suggestion gives Honda permission to publish it without further consideration. ASN (0908)