| The following technical bulletins were published by AERA. |
| | REAR MAIN ROPE SEAL ALTERNATIVE | Rear Main Rope Seal Alternative
The AERA Technical committee supplies the following information on a rear main rope seal alternative. The information provided below was collected over many years. This information is feedback from people like you. People tell us these seals have worked fine for them but will they work for you? AERA expresses no guarantee that they will work 100% of the time but the seals listed below have proven to be the most successful.
During installation, offset or rotate each seal half ? to 3/8 from the main cap parting line. Place dab of anaerobic gel on the ends of the seals that will butt together. Lubricate the seal lip with straight 50 W oil or a bearing assembly lube as those lubes that will stay in place until the engine is started. Seal manufacturers do not recommend white grease alone, because they have seen too many failures from dry startups. This is especially true in rebuilt engines that sit on the shelf for long periods of time before being put into service. This is why you may have seen chunks torn out of the contact face of the seals that have
leaked. If you have ever seen a Ford 390 or 460 tear the whole lip off the seal, it happened because it was dry started and stuck to the crankshaft.
Engine to Detroit Enginetech FM ROL Victor Actual
Be repaired Application
Buick 231 17200 S-1389 BS-40613 RS-29470 JV-742-V Jeep 225
Buick 350 17043 N/A BS-40032 RS-29130 JV-618 Ford 460
Buick 455 17042 N/A BS-30135 RS-29050 JV-730 Ford 200
GM 265/283 17053 S-0629 BS-13241 RS-29005 JV-728 Chev 250*
Caddy 365 17032 S-1196 BS-40245 RS-29040 JV-606 Dodge 318
Ford 312 17032 S-1196 BS-40245 RS-29040 JV-606 Dodge 318
Olds 260 307
330 350 403 17175 N/A BS-6141 RS 29310 N/A Ford 292
Olds 350D
400 425 455 17043 N/A BS-40032 RS-29130 JV-618 Ford 460
Pontiac 301 17091 N/A BS-40048 N/A JV-616 GMC 637
Pontiac 350 17043 N/A BS-40032 RS-29130 JV-618 Ford 460
Pontiac 455 17008 N/A BS-40012 RS-29115 JV-600 Caddy 500
* Install a .090 (2.290 mm) diameter wire in the groove, behind the seal.
It has also been reported that replacing the timing case rope seal with a National seal Part #450446 has proven effective on 455 Buick engines. On engines which use rope anti-rotation holes in the block and cap, fill them with RTV and let dry over night.
The AERA Technical Committee | | CYLINDER BLOCK WATER LEAKAGE | Cylinder Block Water Leakage & Counterbore Repair On
All Cummins Series Engines
This bulletin provides Cummins Engine Company's guidelines for:
A. Applying Cummins Sealant, Part No. 3801048 or equivalent
B. Detecting cylinder block water leaks
C. Repairing the cylinder block counterbore
A. APPLYING CUMMINS SEALANT
Cummins Sealant No. 3801048 or equivalent is effective in preventing coolant from leaking through the joint seal between the cylinder liner and cylinder liner counterbore. It has a pastelike consistency when initially dispensed and hardens with exposure to air at room temperature. It is oil resistant and has a temperature resistance from -75 to 400?F continuous operation and up to 500?F for short periods.
1. Clean the mating surface of the cylinder block and the liner using a suitable hydrocarbon solvent such as naptha, methyl ethyl ketone (MEK) or trichlorethane 1,1,1 (methyl chloroform).
CAUTION: Naptha and methyl ethyl ketone (MEK) are flammable materials and must be used with care. Do NOT use starting fluid as a cleaning agent.
The cylinder block and liner must be free of oil as sealant will not bond to an oily surface.
2. Apply a small bead of sealant 3/64 to 1/16 to the liner flange or cylinder block counterbore before installing the liner (Fig. 1). On engines using counterbore spacer rings, the sealant should be applied to both upper and lower ring surfaces.
NOTE: Excessive amounts of sealant should not be used as this could cause problems in the cooling system, such as plugging the corrosion resistors or cooler cores.
3. The sealant will start curing about 10 minutes after application. For best results, the cylinder liner should be installed as soon as possible after applying the sealant and no longer than one half hour after application to the counterbore.
4. When the liner is installed in the block, the sealant will spread and fill voids between the counterbore and liner, creating a watertight seal. Sealant will not affect the liner protrusion.
5. When using sealant with liner shims, apply it as described above and place the shims on the liner before installation. a small bead of sealant applied to the liner flange will hold the shims in position during installation of the liner.
6. Excess sealant can be removed from the cylinder block surface by using a hydrocarbon solvent.
B. DETECTING CYLINDER BLOCK WATER LEAKS
Sometimes cylinder liner counterbore leaks are mistaken for cylinder head gasket leaks. The following procedure is recommended to determine the cause of the leak:
1. Remove the cylinder heads.
2. Clean the cylinder block deck surface.
3. Plug all water passages.
4. Secure the cylinder liners in the block by using liner clamps. Space the clamps so that an even load will be applied to the liner. Refer to the applicable engine shop manual for liner clamp part numbers and torque values.
5. Fill the cylinder block water system and apply 5 to 10 psi pressure to the block system for 3 to 5 minutes.
6. Check for leakage between the cylinder liner flange and the block.
7. If no leakage is observed and the liner protrusion is within specifications, assemble the engine using the appropriate head gaskets. Refer to the engine shop manual for correct liner protrusion specifications.
8. If leakage is observed then:
a. Measure and record the liner protrusion on all liners.
b. Remove the plugs from the water passages and the liner clamps.
c. Remove the cylinder liners.
d. Check the liner upper counterbore and remove all burrs, dirt and foreign material.
9. If the liner protrusion is not within specifications, the counterbore should be resurfaced and the proper thickness liner shims installed to retain proper liner protrusion. Apply Cummins Sealant No. 3801048 or equivalent and assemble engine.
10. If the liner protrusion is correct and there are no visible major cracks, measurable erosion etc., apply sealant as above and assemble the engine.
DETERMINING WHEN BLOCK REQUIRES SALVAGE
The following information should be used to determine whether or not a block requires repair or salvage. Blocks with counterbore cracks can be used without repair or salvage operations when:
1. Circumferential cracks do not extend to a cylinder head capscrew hole or a water jacket hole. See Fig. 2.
2. Circumferential cracks do not extend beyond one half the width of the counterbore ledge from the radius. (Fig. 2).
3. The counterbore runout and depth are within specification limits to obtain proper liner protrusion by installing liner shims or oversize spacer rings where applicable.
C. CYLINDER LINER COUNTERBORE SALVAGE
The cylinder liner counterbore requires salvage when:
1. The counterbore runout or depth is not within specifications. Begin by removing material from the upper counterbore ledge per standard procedure as outlined in the applicable engine shop manual. For K/KTA engine series refer to Service/Parts Topic 80T 22-6. Remove material from the counterbore ledge using the proper tool until the runout or worn condition has been removed. The cutting depth should not exceed the worn limit counterbore depth listed in the applicable engine shop manual.
Install the proper thickness liner shims to obtain liner protrusion. On some KT/KTA-1150 configurations and on all KT/KTA-2300 and KTA-3067 engines it is possible to vary liner protrusion by the use of oversize counterbore rings. Any combination of oversize rings and shims can be used to obtain correct protrusion. Shims must be installed between liner and counterbore ring. Apply Cummins Sealant No. 3801048 or equivalent and assemble engine.
2. The cylinder liner counterbore must be enlarged and either a counterbore salvage sleeve or oversize liner (on models with oversize liners) installed when:
a. The cracks extend more than one half the width of the counterbore ledge surface from the radius to the sealing edge (Fig. 3).
b. Radial cracks are present in the counterbore and/or extend to one or more capscrew holes.
NOTE: Cracks extending into a capscrew hole can be repaired using the capscrew thread salvage tool kit, Part No. 3375195 or equivalent.
3. The cylinder block should be replaced when:
a. Radial cracks in the counterbore extend to the water jacket.
b. Radial cracks extend to lubricating oil or water passages.
c. Any counterbore cracks in Section C that extend beyond the maximum cutting depth for sleeving.
The AERA Technical Committee | | INSTALLATION OF CARBURIZED GEARS | Installation Of Carburized Gears in NT, NTC, NTA & K
Series Cummins Engines
Due to the carburization method now used for hardening crankshaft
and camshaft gears, it is necessary that these gears be heated in
an oven prior to installation.
CAUTION: The use of a heating torch, or means other than a
heating oven, is not recommended for expanding gears during
installation.
Carburized gears should be heated in a pre-heated oven at 400^F
(205^C) for a minimum period of one hour before installation.
It is also recommended that when heating any type gear for
installation, where possible, an oven instead of a torch should
be used.
The AERA Technical Committee
September 1975 - SPB 30
##END## | | CYLINDER HEAD CAUTION | Cylinder Head Caution For
1997-2000 GM 5.7L VIN G Engines
The AERA Technical Committee offers the following information on a cylinder head caution for 1997-2000 GM 5.7L VIN G engines. This information should be considered while the heads are removed from the engine for service work.
If heat cleaning or straightening, do not exceed 400°F (204°C) of temperature and avoid a direct flame process.
Check the heads for flatness .003 within any 6.0 and a max of .004 (0.1mm) as shown in Figure 1. Repeat checking procedure on cylinder block with a max of .004 (0.1mm).
If the heads require surfacing, ensure shop personal is aware and understand that the minimum thickness on these heads is 4.732 (120.20 MM) as shown in Figure 2.
If the measured valve guide to valve clearance indicates wear beyond service limits, the current available repair from GM is to fit with over size stem replacement valves. Or, a thin wall guide liner may also be considered at this time.
When the cylinder head is being serviced for a valve job, GM states the intake valves are to be replaced (do not grind). Intake valves are of an ultra light design and have insufficient material for grinding. (REPLACE ONLY is GM?s recommendation).
Reseating the cylinder head seats can be accomplished using conventional accepted method as they can be ground or machined.
Refacing Angle for Valves & Seats:
Intake valve NA
Intake seat 46°
Exhaust valve 45°
Exhaust seat 46°
Starting with the 1999 model year, the valve stem seals are color coded to indicate specific location. Intake seals are black in color and the exhaust seals are brown in color. Be sure to use the valve stem oil seal installer Part # J42078 for proper installation of the valve seals.
The AERA Technical Committee | | PREMATURE PISTON DAMAGE | Premature Piston Damage On
GM 2.5L (151 CID) TBI Engines
AERA members should consider the following when a GM 2.5L (151CID) TBI (Throttle Body Injection) has been diagnosed with premature piston failure.
Most often the pistons are damaged near the crown (top) whenever the engine has been subject to improper combustion. Improper combustion can be the result of an incorrect air/fuel ratio, improper ignition timing, a malfunctioning computer or EGR (Exhaust Gas Recirculation) system. Even if the EGR valve itself is operating, a blocked passage in the cylinder head or intake manifold can still lead to piston failures. When the piston hasnot yet failed, an early sign of damage is a blue discolorationof the wrist pin.
It is important to clean all passages in the intake manifold whenever the cylinder head of an engine is remanufactured. If the manifold is not removed with the cylinder head, AERA recommends that the installing mechanic verify that passages are free of debris. Several machine shops have reported repeated
piston failures because the EGR passage was plugged.
For additional information see AERA Bulletins: TB 400, 374
The AERA Technical Committee | | CHANGE IN PISTON PIN TO PIN BOSS FIT | Piston Pin To Piston Fit Change On
Continental F-400, F-600 & Y-400 Engines
The piston pin bores have been changed as listed below:
Engine From To
-----------------------------------------------------------------
F400 .8597-.8595 .8594-.8592
F600 .8597-.8595 .8594-.8592
Y400 .7088-.7086 .7087-.7085
The AERA Technical Committee |
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