Abstract:
A method for reducing noise in an engine is disclosed whereby a camshaft phaser is modified by a lockout to limit the movement of the phaser during operation. The lockout is inserted into the phaser&#39;s gear without removing the front engine cover using a novel method.

Description:
BACKGROUND 
     Modern day automobile engines have become sophisticated machinery controlled by computers to handle virtually all aspects of the operation of the vehicle. In recent years, the control over various aspects of the engine have increased to the point where almost every movement or operation of the engine is governed or monitored by a computer. The present invention relates to a particular aspect of the engine&#39;s operation under the control of the vehicle&#39;s onboard computer, or engine control unit (“ECU”). 
     One key characteristic of a vehicle&#39;s engine is the power generated by the engine, which is a function of the degree and extent that the intake and exhaust valves open, how long the stay open, and the timing of when they open and close. If the valves open slightly longer and/or a slightly later in the ignition cycle, or if they are opened for a prolonged portion of the cycle, the engine will exhibit a distinct muscle-car rumble with an accompanying high-rpm horsepower. Conversely, reducing the opening of the valves and opening them slightly earlier results in a smoother engine percussion with a steady idle, good low-rpm torque, superior fuel economy and lower emissions. Traditionally, the control of the valve movements and timing in all aspects have been controlled by a camshaft with carefully calibrated lobes that pushed the valves open at exactly the right time and maintain the opening for the desired duration. 
     In today&#39;s engines, camshaft phasers play an important role in a key aspect of the cam timing: the camshaft&#39;s position relative to the crankshaft, and thus the position of the pistons connected to it. If one advances or retards the cam slightly relative to the crankshaft, the valves will open and close sooner (or later) relative to the piston coming up in the bore. When the cam advances earlier, the engine will sound smoother but will lack top end horsepower. “Retarding” the cam, i.e., turning it so the valves open and close late, is better for horsepower but results in what some consider to be an overly loud, disruptive noise (albeit one that some vehicle owners prefer). Traditionally, engine manufacturers set a certain amount of cam advance or retard while designing the engine. This could be accomplished by moving the whole cam sprocket gear one tooth forward or backward on the timing chain, or through aftermarket adjustable sprockets that could be rotated relative to the camshaft&#39;s original position. 
     A cam phaser is an adjustable camshaft sprocket mounted on the chain, and can be turned by means of a computer-controlled solenoid. Rather than pre-setting a certain amount of advance or retard, the computer can advance the cam or cams in situ at low rpm to enhance driveability, and retard the cam or cams at high rpm for more horsepower. Cam phasers may be specially designed for a particular engine, and computer-controlled cam gears for specific engines have the ability to adjust camshaft position (and thus valve opening and closing) while the engine is running. In the case of Ford modular engines that use two camshafts, two cam phasers are used. To actuate the cam phaser, engine oil is pressure fed to the cam phasers through a series of passageways in the cylinder heads and camshafts. The engine computer controls a pair of solenoids that adjusts this oil flow into and out of the cam phaser&#39;s control chambers, giving the ability to retard the cams in some cases up to 60 degrees or crank rotation. 
     When the cams are retarded approximately 20-40 degrees during part throttle engine operation, it takes less power to turn the engine over. This helps to increase the engine&#39;s fuel efficiency. Another power benefit is that the cam phasers allow the camshafts to always be in the optimal position for maximum power, regardless of what the engine&#39;s rpm is. The engine thus in able to generate more torque and horsepower and extends the high rpm powerband by, in some cases, an extra 800-1000 rpm. 
     However, one downside of stock cam phasers it is that they are exceptionally sensitive to changes, specifically the reduction of, oil pressure. Since the cams can theoretically be retarded by up to 60 degrees, when an issue arises, it causes the cam phaser to no longer have controlled movement. This can cause “knocking” or excessive engine noise if there is interference between the cam and the piston. This minimal piston to valve clearance also limits most engines to fairly small cam profiles with very little overlap. Thus, a solution is needed to address the issue of excessive movement with inadequate clearance due to the wide range of movement resulting from the camshaft phaser. In addition to this, the rapid, and violent action of the cam phaser moving from each end of the mechanical limit without control can cause the cam phaser to separate from the camshaft causing severe engine damage. 
     SUMMARY OF THE INVENTION 
     The present invention is a camshaft phaser noise repair kit and method that, when combined with a recalibration of a vehicle&#39;s onboard computer, allows for a reliable, economical repair of an engine&#39;s variable camshaft timing phaser. The mechanical elements of the present invention physically limit the movement of the camshaft phasing when installed in the camshaft, reducing the volume of oil needed for camshaft phasing adjustment. The elements also limit the total travel rotation of the phaser, which eliminates or reduces the failure of the phaser system and prevents engine damage while reducing noise. The camshaft phaser uses engine oil pressure to hydraulically control the camshaft phasing. Over time, normal engine wear causes a reduction in supplied oil pressure, specifically at idle, and the result is a loss of control of the camshaft phasing. This loss of control can lead to engine failure if not addressed as the internal pieces of the camshaft phaser impact as a result of a lack of oil pressure. The repair kit of the present invention avoids costly dealer repairs and can be installed by the vehicle owner economically, and the fix permanently limits the camshaft phasing so as to implement a one time repair. 
     The kit of the present invention includes a lockout component that is inserted into the phaser. Made from a high strength material such as 6061-T6 billet aluminum, the mechanical lockouts fit directly inside the factory-installed cam phaser with no further modifications necessary. These lockouts also prevent failure in the cam phaser when using aftermarket springs that use increased force when compared with stock springs, allowing for the use of aftermarket camshaft profiles. By locking the factory cam phaser, the engine can use higher duration and lift camshafts that would otherwise cause issues with the piston to valve relationship. The lockout completely precludes the phaser from moving, which allows for greater durability in applications where the cam phaser might be more prone to failure in racing environments with aftermarket springs and camshafts. 
     To implement the new settings with the lockouts installed, the engine control unit is reflashed with a kit included programmer that allows for proper engine calibration with the updated, limited range in camshaft phasing. The ability to update the ECU via a remote database, such as by accessing the internet, allows a user the opportunity for quick and inexpensive access to appropriate recalibration datasets needed for newer or unknown factory calibrations that the OEMs may have released after the device is installed. For example, when transferring files from the update server to the programmer connected to the ECU, the internet update applications acts as a simple pass through application to communicate or exchange the data. The update server determines the proper files needed by the programmer that matches the calibration data currently used in the vehicle, and encrypts the files via a propriety encryption scheme using an encryption key known only to the programmer and update server. The programmer receives the encrypted data and decrypts the files using this encryption key. The encryption key is preferably a dynamic random key that is regenerated each time the programmer establishes communications with the update server via the update application. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a kit embodying elements of the present invention; 
         FIG. 2  is an elevational view, partially cut-away, showing the position of the wedge tool and chain; 
         FIG. 3  is an elevational view, partially exploded, of the cam phaser and cam shaft; 
         FIG. 4  is a perspective view, partially exploded, of the lockout and phaser; 
         FIG. 5  is a perspective view, partially exploded, of the phaser with the lockout installed; 
         FIG. 6  is an elevational, cross sectional view of the chain after the wedge tool is removed; 
         FIG. 7  is a perspective view of the coupling of the programmer with the engine control unit through the vehicle&#39;s dash. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     For certain vehicles, the most common failure or issue with the engine is the cam phaser, and specifically cam phaser knock. Cam phaser knock usually results in the eventual failure of the cam phaser due to excessive movement, which causes the pin in the phaser to fracture the housing of the phaser, and in extreme cases the entire assembly can fail and damage the engine. The present invention addresses this problem by ensuring that the cam phasers do not suffer premature failure. It will reduce or eliminate any knocking noise heard from the front valve cover/timing cover area related to the phasers. The present invention comprises a cam phaser lockout kit and method for updating a Ford modular engine using the same. The kit is an engine modification that permanently modifies the camshaft phaser and uses a recalibration to adjust the engine&#39;s timing in accordance with the changes to the phaser. 
       FIG. 1  illustrates the components of the kit, including two mechanical lockouts  10 , a data storage device  20  such as a CD-ROM, camshaft phaser bolts  30 , a wedge tool  40  including a tether or cable  42 , and a programmer  50 , which can all be shipped in a shipping container  60  for ease of delivery. To implement the method and kit of the present invention, a synopsis of the complete installation will be set forth below. 
     To install the phaser repair kit, the vehicle&#39;s battery is first disconnected and all of the components necessary to access valve covers are removed. Once all other components are removed, the valve covers are removed although the front cover can be left in place. 
     The kit includes a timing chain wedge tool  40 , shown in  FIG. 1 . The first step is to carefully fix the timing chains while the phaser is modified. The wedge tool allows for locking of the timing chains  110  on a vehicle without having to remove the front cover  120 . Once the valve covers are removed, the wedge tool  40  is dropped into position between the chains  110  ( FIG. 2 ), and a long screwdriver or similar tool can be used to further drive the wedge tool  40  into a tightly wedged position between the chains  110 , effectively immobilizing the timing chains. The wedge tool includes a small notch in the top surface to allow a tool such as the screwdriver to be used to push the piece into place. The immobilization of the timing chains  110  can be verified by using a light tugging on the wedge tool&#39;s cable  42  to ensure that the wedge tool is firmly engaged with the chains  110 . The wedge tool  40  has two sides, one flat  44  (which goes up against the fixed guide) and one  46  with a curve to it (which goes up against the pivoting guide). The shape of the wedge tool  40  allows it to engage the chains  110  without being pushed all the way through the chains. Once the wedge tool  40  into place, the pull cord  42  is left hanging out of the top of the engine so that once the repair is complete, the cord may be pulled swiftly to dislodge the wedge and allow it to be easily removed. 
     Once the wedge tool  40  is firmly in place, one of the sections of chain is paired with a tooth on the phaser  80  using, for example, a mark  70  on the phaser from a felt pen and a mark  72  on the chain from a felt pen. These alignment marks ensure that the phaser  80  is returned to the exact same orientation that it occupied originally. 
     Once the wedge tool  40  is in place and the alignment markings are made, the large camshaft bolt  120  holding the phaser  80  to the camshaft  90  is removed and the camshaft phaser  80  is removed ( FIG. 3 ). 
     The next step is to insert the lockout  10  into the phaser  80 . The phaser is secured in a vice to hold the assembly in place as the bolts are removed to release the cover  95 . It is preferable to remove four of the five bolts holding the phaser together and loosen the remaining long bolt. One of the long bolts goes through the assembly and comes out the other side where it holds the spring for the phaser assembly in tension. This bolt will be left in place and only loosened to allow the rear cover  95  to rotate out of the way. After the bolts are loosened, one can remove the phaser assembly from the vice and place it on a workbench, where the remaining bolts can be removed by hand. 
     The cover plate  95  is rotated on the remaining bolt  98  of the phaser  80 , cautiously as there is a spring-loaded small check valve  105  that can be disconnected by release of the spring potential energy. Care is needed to prevent the valve  105  from dislodging from the phaser during this step (See  FIG. 4 ). When the cover plate  95  is rotated away as shown in  FIG. 4 , the inner compartment of the phaser  80  is exposed showing five vanes  88  adjacent five lugs  86  within the compartment. Between adjacent lugs  86  and vanes  88  is a cavity  89 , and the mechanical lockout  10  is sized to fit into this cavity and occupy the cavity with a snug fit. The lockouts  10  are precision machined to fit into a selected one cavity  89  better than the rest. Once the optimal cavity  89  is identified, the gear and lockout  10  will experience a slight preload that will resist movement of the lockout  10 . Note that the invention will work with the lockout  10  in any of the cavities  89 , but the tightest fit is preferred. 
     Once the lockout  10  is installed in the cavity  89  ( FIG. 5 ), the cover plate is returned to its original position and the bolts are re-inserted and tightened, taking time to ensure that the check valve  105  is securing in place. The cover plate  95  is secured to the back on the gear. The gear is now re-installed back into the engine ( FIG. 6 ). The first step is to slide the phaser  80  back in place under the timing chain  110 , paying attention to make sure the alignment marks  70 ,  72  are aligned. Once the phaser  80  and chain  110  back in place and lined up one can slide the phaser back onto the front of the camshaft snout. If the camshaft  90  has moved after taking the phaser  80  off it may be necessary to spin the cam over slightly to get it to line up. Stock cams have a plug in the back of the cam that can be used with a ⅜″ extension and ratchet to move the camshaft  90 . Aftermarket cams usually have a hex built into the cam core itself for this purpose. 
     After returning the phaser  80  to the camshaft  90  and aligned, one can proceed to installing the bolt  30 . It is important to ensure that the phaser  80  is fully seated on the cam snout and that the pin is engaged in the camshaft. Once the phaser bolt  30  in place, the wedge tool  40  can be withdrawn by pulling on the cord  42  to remove it from the engine. The next step will be torqueing the camshaft bolt  30 . In order to torque the bolt  30 , it may be necessary to utilize a second ratchet (preferably a breaker bar) installed on the crankshaft bolt to hold the engine from spinning over when the bolt is torqued. With the crankshaft held in position the camshaft phaser bolt  30  can be adequately torqued to its proper limit. After the camshaft bolt  30  is torqued the remaining components removed to begin the procedure can be reinstalled. 
     To install the new timing data into the engine&#39;s ECU, the programmer  50  is plugged into the OBD-II port  200  (typically located beneath the steering column) with the engine off ( FIG. 7 ). Ensure the cable  205  is securely connected and does not become disconnected during the session. The vehicle is placed in accessory mode by turning the key forward kept in that position until the procedure is complete. The display on the programmer  50  will produce prompts to transfer the data. 
     The components of the repair kit physically limit the camshaft phasing when installed. This limits the total travel rotation of the phaser which eliminates the failure of the phaser system and prevents possible engine damage. The vehicle&#39;s ECU is reflashed with the included programmer unit using an update application that allows for proper engine calibration with the limited range in camshaft phasing. The update server encrypts these files via a proprietary encryption scheme using an encryption key known only to the programmer and update server. The programmer decrypts the files with this key. The encryption key may be a dynamic random key that is regenerated each time the programmer establishes communications to the update server via the update application. 
     The kit includes a programmer unit  50  that is used in conjunction with the installation of the mechanical parts. The programmer unit  50  reads the installed factory calibration from the ECU, and then generates an altered calibration. The altered calibration adjusts the engine parameters to allow for the limitation of the camshaft phaser travel which prevents error codes and/or limited power mode(s) that would be associated with the limited camshaft phaser travel from the installed mechanical parts. 
     Example 1 
     The following calibration data is from a production file (AL3A-14C204-BJB) used in a 2009 Ford F-150 with the 5.4 L 3V SOHC V8 Engine. 
     Calibration Disclosure—Variable Camshaft Timing Hardware Disable 
     Purpose: Disables Camshaft Position System Performance diagnostics as camshaft phasing will be fixed with Repair Kit installed. 
     Ford Parameter Name: P0011SW 
     
         
         
           
             “VALUE: 02” change to “00”=disables DTC P0011
 
Purpose: Disables Mode6 reporting for VCT system as camshaft phasing will be fixed with Repair Kit installed, and data will be unnecessary or erroneous if reported.
 
Ford Parameter Name: TESTIDMAP_4
 
             “VALUE: 110001101001” change to “110000001001”=disable VCT Mode6 reporting
 
Purpose: Disables VCT hardware configuration in ECU. Similar result to P0011SW alteration.
 
Ford Parameter Name: VCAMHP
 
             “VALUE: 01” change to “00”=disables VCT hardware configuration
 
Purpose: Disables VCT configuration in ECU. Similar to VCAMHP alteration.
 
Ford Parameter Name: VCT_CONFIG
 
             “VALUE: 03” change to “00”=disables VCT configuration
 
Purpose: Disables OBDII reporting for VCT system as camshaft phasing will be fixed with Repair Kit installed. Similar to P0011SW alteration.
 
Ford Parameter Name: VCT_OBDII_SW
 
             “VALUE: 01” change to “00”=disables OBDII reporting for VCT. 
           
         
       
    
     Calibration Disclosure—Drivability Improvements/Engine Speed Limit Raised 100 RPM 
     Purpose: Raised to prevent rev limit stutter on high mileage vehicles that have slower shifting transmissions. 
     Ford Parameter Names: ESL_CTL_LMT 
     
         
         
           
             “VALUE:5250” Add+100
 
Ford Parameter Name: NLMTHI_0
 
             “VALUE:5700” Add+100 
           
         
       
    
     Additional spark advance (+1 deg) 
     Purpose: Raised to smooth engine running (NVH) 
     Ford Parameter Name: SPK_ADD 
     
         
         
           
             “VALUE: 0” Add+1 
           
         
       
    
     WOT Fuel delay set to zero 
     Purpose: Decreased to improve performance at wide open throttle. 
     Ford Parameter Name: FN 1311 
                                                                                                                                     RPM                1000   1666.667   2333.333   3000   3500   3750   4000   4500   5000   5500                        5   7   7   7   7   7   7   7   7   7   7       4   7   7   7   7   7   7   7   7   7   7       3   7   7   7   7   7   7   7   7   7   7       2   4   4   4   4   4   4   4   4   4   4       1   0   0   0   0   0   0   0   0   0   0                    
All set=0
 
All set=0.
 
     Desired Idle Speed raised 25 RPM 
     Purpose: Raised to smooth engine running at idle (NVH) 
     Ford Parameter Name: IS_DRBASE 
     
         
         
           
             “VALUE: 525” Add 25 RPM
 
Ford Parameter Name: IS_NUBASE
 
             “VALUE: 600” Add 25 RPM 
           
         
       
    
     The forgoing description is intended to be illustrative but not limiting. The present invention is not limited to the foregoing descriptions and figures, but rather is intended to accompany and include any and all modifications and substitutions that would be recognized and apparent to one of ordinary skill in the art.