Differences
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| techtalk:ref:engmech01a [2018/08/31 11:04] – [Timing Inspection Hole and Plug - Sealing and Thread Repair] hippysmack | techtalk:ref:engmech01a [2024/01/14 16:45] (current) – hippysmack | ||
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| * These are aluminum internal (case) and steel external (plug) threads (5/ | * These are aluminum internal (case) and steel external (plug) threads (5/ | ||
| - | * It is a common occurrence to damage these threads or for them being found to be damaged. Whoever threaded the plug in last may have not taken the time to insure proper thread starting before using a wrench to install the plug and cross-threaded them. Over tightening the plug can crack / stretch the threads and thermal expansion can warp and gall them ((hippysmack)). Sometimes the threads get corroded and galled to the point that removing the plug takes the threads out with it. You can't be certain that the threads haven' | + | * It is a common occurrence to damage these threads or for them being found to be damaged. Whoever threaded the plug in last may have not taken the time to insure proper thread starting before using a wrench to install the plug and cross-threaded them. Over tightening the plug can crack / stretch the threads and thermal expansion can warp and gall them ((hippysmack)). Sometimes the threads get corroded and galled to the point that removing the plug takes the threads out with it. You can't be certain that the threads haven' |
| - | * The threads can appear to strip for no apparent reason. The problem with drain and timing plugs are the same. ((Dr Dick of the XLFORUM | + | * The threads can appear to strip for no apparent reason. The problem with drain and timing plugs are the same. ((Dr Dick of the XLFORUM |
| - | * Common occurrences include: ((Dr Dick of the XLFORUM | + | * Common occurrences include: ((Dr Dick of the XLFORUM |
| * No problems the last time the plug was installed. | * No problems the last time the plug was installed. | ||
| * No problems when the plug was pulled out last. | * No problems when the plug was pulled out last. | ||
| * But when trying to re-install the plug and with little to no torque, the threads did strip. | * But when trying to re-install the plug and with little to no torque, the threads did strip. | ||
| - | * You may have had it out 100 times before and can’t understand what happened now. ((Dr Dick of the XLFORUM | + | * You may have had it out 100 times before and can’t understand what happened now. ((Dr Dick of the XLFORUM |
| **Case in Point**: | **Case in Point**: | ||
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| * Below is a case drain (left) and a Colony acorn style timing plug (right). | * Below is a case drain (left) and a Colony acorn style timing plug (right). | ||
| - | |See this undercut unthreaded area? \\ All oil plugs are made like this in Milwaukee. ((Photo by Dr Dick of the XLFORUM | + | |See this undercut unthreaded area? \\ All oil plugs are made like this in Milwaukee. ((Photo by Dr Dick of the XLFORUM |
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| * If there was no undercut, the threads would have incomplete form next to the underside of head. These incomplete threads wouldn’t allow the flat sealing face of the plug to contact the case before the threads were bound up in the tapped hole. So, the malformed threads get cut away by the undercut. The (necessary) undercut is where the problem comes from. The tapped threads in the case run the length of the hole except that there is a (one thread) counter-bore in the front of the case. | * If there was no undercut, the threads would have incomplete form next to the underside of head. These incomplete threads wouldn’t allow the flat sealing face of the plug to contact the case before the threads were bound up in the tapped hole. So, the malformed threads get cut away by the undercut. The (necessary) undercut is where the problem comes from. The tapped threads in the case run the length of the hole except that there is a (one thread) counter-bore in the front of the case. | ||
| - | * In both positions, when the plug gets put into the hole (hand tight) to the sealing surface, there are a few aluminum threads that end up in the undercut of the plug. The plug thread in this area doesn’t have a mating thread when you tighten the plug. It is unsupported. ((Dr Dick of the XLFORUM | + | * In both positions, when the plug gets put into the hole (hand tight) to the sealing surface, there are a few aluminum threads that end up in the undercut of the plug. The plug thread in this area doesn’t have a mating thread when you tighten the plug. It is unsupported. ((Dr Dick of the XLFORUM |
| - | * The aluminum threads above the undercut do mate to the plug. Then, you put the wrench to it. Under the tightening torque, the aluminum female threads (that are in contact with the male plug threads, above the undercut) get slightly deformed. The aluminum threads, in contact with the plug, get yanked towards the aluminum threads that are just hanging free in the undercut. This creates a sort of cross-threaded condition in the case. A deformed thread just above a non-deformed thread that lives in the undercut. At this point the plug is tight, as in (the last time you tightened it). ((Dr Dick of the XLFORUM | + | * The aluminum threads above the undercut do mate to the plug. Then, you put the wrench to it. Under the tightening torque, the aluminum female threads (that are in contact with the male plug threads, above the undercut) get slightly deformed. The aluminum threads, in contact with the plug, get yanked towards the aluminum threads that are just hanging free in the undercut. This creates a sort of cross-threaded condition in the case. A deformed thread just above a non-deformed thread that lives in the undercut. At this point the plug is tight, as in (the last time you tightened it). ((Dr Dick of the XLFORUM |
| - | * The next time you remove the plug, (this time) something is present that was too subtle to notice when you break the plug free. It turns freely out about 1/8 turn and then gets too tight to remove by hand so you put the wrench on it and spin the plug out. ((Dr Dick of the XLFORUM | + | * The next time you remove the plug, (this time) something is present that was too subtle to notice when you break the plug free. It turns freely out about 1/8 turn and then gets too tight to remove by hand so you put the wrench on it and spin the plug out. ((Dr Dick of the XLFORUM |
| - | * It’s right here that the stripping has begun. It got tight because the plug was forcing the deformed female threads back into sync with the non-deformed female threads that live in the undercut. So, the deformed threads get flexed back by the undercut threads as they need to get back in sync for the plug to unscrew. This force of synchronization flexes the undercut threads also. Flexing a piece of cast aluminum back and forth will cause it to break or let loose. ((Dr Dick of the XLFORUM | + | * It’s right here that the stripping has begun. It got tight because the plug was forcing the deformed female threads back into sync with the non-deformed female threads that live in the undercut. So, the deformed threads get flexed back by the undercut threads as they need to get back in sync for the plug to unscrew. This force of synchronization flexes the undercut threads also. Flexing a piece of cast aluminum back and forth will cause it to break or let loose. ((Dr Dick of the XLFORUM |
| - | * So, it’s not necessarily the design of the oil plug that causes the damage but more of the way the wrenching gets done over the years. Because the damage gets done on the previous in / out cycle, it gets hidden by time the next fatal in / out happens. That’s why it seems to strip out of the clear blue sky. ((Dr Dick of the XLFORUM | + | * So, it’s not necessarily the design of the oil plug that causes the damage but more of the way the wrenching gets done over the years. Because the damage gets done on the previous in / out cycle, it gets hidden by time the next fatal in / out happens. That’s why it seems to strip out of the clear blue sky. ((Dr Dick of the XLFORUM |
| - | + | |Timing inspection hole location on a pre-91 engine case \\ (centered between the two cylinders on the left crankcase) ((photo by trafetto of the XLFORUM | |
| - | + | ||
| - | |Timing inspection hole location on a pre-91 engine case \\ (centered between the two cylinders on the left crankcase) ((photo by trafetto of the XLFORUM | + | |
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| ===== Temporary Repair Options ===== | ===== Temporary Repair Options ===== | ||
| - | In an emergency or as patch until you can have a permanent solution done, here are some possible ideas in the Sportsterpedia to keep you riding ([[techtalk: | + | In an emergency or as patch until you can have a permanent solution done, here are some possible ideas in the Sportsterpedia to keep you riding ([[techtalk: |
| ====== Installing the Plug ====== | ====== Installing the Plug ====== | ||
| - | * **Torque value**: 10-15 ft. Lbs. (14-21 Nm) on a dry plug with good threads in the case. ((Jordan1200 of the XLFORUM | + | * **Torque value**: 10-15 ft. Lbs. (14-21 Nm) on a dry plug with good threads in the case. ((Jordan1200 of the XLFORUM |
| * You should use anti-seize on the plug threads before installing it to help prevent galling and damage upon the next removal. The anti-seize will add pre-load to the threads so you should also lower the torque applied when installing the it to avoid a new problem with a broken or stretched bolt. ((Hippysmack)) | * You should use anti-seize on the plug threads before installing it to help prevent galling and damage upon the next removal. The anti-seize will add pre-load to the threads so you should also lower the torque applied when installing the it to avoid a new problem with a broken or stretched bolt. ((Hippysmack)) | ||
| - | * The threads can strip easily so be careful with it. Clean the threads for both the plug and the hole, thread the plug into the case using fingers only, then snug up to "firm plus a little more". Regarding the "just snug": you have to trust this stuff. Too tight and you got a problem. The plug has fine threads that resist loosening from vibration. " | + | * The threads can strip easily so be careful with it. Clean the threads for both the plug and the hole, thread the plug into the case using fingers only, then snug up to "firm plus a little more". Regarding the "just snug": you have to trust this stuff. Too tight and you got a problem. The plug has fine threads that resist loosening from vibration. " |
| * The plug and the case threads are different metals and torque will usually always side towards the metal on the plug. This leaves the aluminum case threads more vulnerable to damage from over-torque. | * The plug and the case threads are different metals and torque will usually always side towards the metal on the plug. This leaves the aluminum case threads more vulnerable to damage from over-torque. | ||
| * Blue Loctite can also be used to seal the threads ((IronMick)) but it also adds more torque necessary to remove the plug. If you know you already have a certain amount of thread damage (as in when you installed the plug last), increasing torque while removing the plug may add to that damage. | * Blue Loctite can also be used to seal the threads ((IronMick)) but it also adds more torque necessary to remove the plug. If you know you already have a certain amount of thread damage (as in when you installed the plug last), increasing torque while removing the plug may add to that damage. | ||
| - | * If you can't spin the plug in or out by hand, don't put a lot of torque on it. It may not hold on the next seating. You my want to GENTLY retighten it or try chasing the threads first. ((Dr Dick of the XLFORUM | + | * If you can't spin the plug in or out by hand, don't put a lot of torque on it. It may not hold on the next seating. You my want to GENTLY retighten it or try chasing the threads first. ((Dr Dick of the XLFORUM |
| - | * The first time you loosen one of these plugs it may be real tight. Don't make the mistake of over-tightening when you install it. You'll probably find that they get tighter all by themselves. ((Dr Dick of the XLFORUM | + | * The first time you loosen one of these plugs it may be real tight. Don't make the mistake of over-tightening when you install it. You'll probably find that they get tighter all by themselves. ((Dr Dick of the XLFORUM |
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| ====== Permanent Repair Options | ====== Permanent Repair Options | ||
| - | * In theory, the best advice is to split your cases and have it done proper by your local machine shop. ((MTD of the XLFORUM | + | * In theory, the best advice is to split your cases and have it done proper by your local machine shop. ((MTD of the XLFORUM |
| * However, the foregoing is under the assumption the engine is assembled. This would obviously not be as big of an issue with the engine out and the case split. Repairs of the timing inspection hole are much easier for you or most machine shops without the flywheel in the way or concerns of metal shavings getting into the engine. | * However, the foregoing is under the assumption the engine is assembled. This would obviously not be as big of an issue with the engine out and the case split. Repairs of the timing inspection hole are much easier for you or most machine shops without the flywheel in the way or concerns of metal shavings getting into the engine. | ||
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| * Try an [[techtalk: | * Try an [[techtalk: | ||
| * Try [[techtalk: | * Try [[techtalk: | ||
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| ===== Chasing the Existing Threads ===== | ===== Chasing the Existing Threads ===== | ||
| - | See also the [[techtalk: | + | See also the [[techtalk: |
| - | * A tap and a die is normally used to chase the threads in the case and on the plug respectively back to their original shape / cleanliness and usually done with plenty of good cutting oil. \\ However, for this application, | + | * A tap and a die is normally used to chase the threads in the case and on the plug respectively back to their original shape / cleanliness and usually done with plenty of good cutting oil. \\ However, for this application, |
| ==== Tools Needed ==== | ==== Tools Needed ==== | ||
| * You can generally purchase these at most machinist supply stores online cheaper than you can buy them from motorcycle supply stores 'made for Harleys' | * You can generally purchase these at most machinist supply stores online cheaper than you can buy them from motorcycle supply stores 'made for Harleys' | ||
| * They do not have to be expensive. They simply have to be the right size and shape for your application. | * They do not have to be expensive. They simply have to be the right size and shape for your application. | ||
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| |**5/ | |**5/ | ||
| - | |{{:techtalk: | + | |{{techtalk: |
| * **Choosing the right tap** | * **Choosing the right tap** | ||
| - | * A bottoming tap only has a very short taper on the end to allow it to get inside the hole. It will immediately cut the threads before it bottoms out into the flywheel. ((Whitewalls of the XLFORUM | + | * A bottoming tap only has a very short taper on the end to allow it to get inside the hole. It will immediately cut the threads before it bottoms out into the flywheel. ((Whitewalls of the XLFORUM |
| - | * A tapered (not to be confused with tapered thread) or plug style tap has a longer tapered end. The tapered end does not cut any threads and it will bottom out against the flywheel before the threads are finished cutting. It is designed to help you center up in the hole for tapping new threads. If you continue turning from that point, you risk back pressure on the tap which could crack the case. If you aren't planning on doing this again, you could cut off the taper ((iNSaNeSHaNe of the XLFORUM | + | * A tapered (not to be confused with tapered thread) or plug style tap has a longer tapered end. The tapered end does not cut any threads and it will bottom out against the flywheel before the threads are finished cutting. It is designed to help you center up in the hole for tapping new threads. If you continue turning from that point, you risk back pressure on the tap which could crack the case. If you aren't planning on doing this again, you could cut off the taper ((iNSaNeSHaNe of the XLFORUM |
| * **Choosing the right die** | * **Choosing the right die** | ||
| * You can use a standard round or a hex die. Either will do the job and possibly be held in your palm for use. But, if your threads are bad enough to need repairing this way, you probably need to buy the wrench for it. | * You can use a standard round or a hex die. Either will do the job and possibly be held in your palm for use. But, if your threads are bad enough to need repairing this way, you probably need to buy the wrench for it. | ||
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| * **Thick lube or grease** is needed to catch and hold the shavings and keep them from flinging through the engine case. You will need to clean the threads after your done repairing them. Using compressed air from the engine out through the hole will not work while using lube since the shavings will cling to it and not be blown out of the hole. | * **Thick lube or grease** is needed to catch and hold the shavings and keep them from flinging through the engine case. You will need to clean the threads after your done repairing them. Using compressed air from the engine out through the hole will not work while using lube since the shavings will cling to it and not be blown out of the hole. | ||
| * **Optional Items**: | * **Optional Items**: | ||
| - | * **Panty Hose**: Stuff a small piece (3" - 4" long) of panty hose into the hole prior to any work (between the flywheel and the case while allowing a small amount to be gotten to later with a pick). Make sure the material is not in the way of your work. You wouldn' | + | * **Panty Hose**: Stuff a small piece (3" - 4" long) of panty hose into the hole prior to any work (between the flywheel and the case while allowing a small amount to be gotten to later with a pick). Make sure the material is not in the way of your work. You wouldn' |
| ==== Thread Repair ==== | ==== Thread Repair ==== | ||
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| ===== Using an Aftermarket Drain Plug or Bolt with Longer Threads ===== | ===== Using an Aftermarket Drain Plug or Bolt with Longer Threads ===== | ||
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| The factory timing hole plug can be up to app. 1/2 the length of the threads in the case on Evo engines and the entire length minus a couple threads on IHs. If you have stripped threads in the front half of the case, chances are the threads in the rear half of the case hole are still good. | The factory timing hole plug can be up to app. 1/2 the length of the threads in the case on Evo engines and the entire length minus a couple threads on IHs. If you have stripped threads in the front half of the case, chances are the threads in the rear half of the case hole are still good. | ||
| * Aftermarket 'drain plugs' can be purchased at auto parts stores and can be a suitable replacement for the factory plug. | * Aftermarket 'drain plugs' can be purchased at auto parts stores and can be a suitable replacement for the factory plug. | ||
| - | * You'll need to check the O.D. of the head and make sure it will seat properly to the machined mating surface in the case. If it's too big, you may need to round sand or grind the head diameter slightly with a grinder. ((jordan1200 of the XLFORUM | + | * You'll need to check the O.D. of the head and make sure it will seat properly to the machined mating surface in the case. If it's too big, you may need to round sand or grind the head diameter slightly with a grinder. ((jordan1200 of the XLFORUM |
| - | * While using a bench grinder, mark one flat of the head with a sharpie marker to verify when you've made a complete rotation of the drain plug. This visual helps in allowing you to keep the head the same diameter all the way around. Keep nice even pressure while turning the plug against a medium grit wheel and clean the edges on a wire wheel (with light pressure applied). ((jordan1200 of the XLFORUM | + | * While using a bench grinder, mark one flat of the head with a sharpie marker to verify when you've made a complete rotation of the drain plug. This visual helps in allowing you to keep the head the same diameter all the way around. Keep nice even pressure while turning the plug against a medium grit wheel and clean the edges on a wire wheel (with light pressure applied). ((jordan1200 of the XLFORUM |
| - | * Some, if not all, aftermarket drain plugs are longer than the stock plug and will catch those last few threads in the rear of the hole. ((IronMick of the XLFORUM | + | * Some, if not all, aftermarket drain plugs are longer than the stock plug and will catch those last few threads in the rear of the hole. ((IronMick of the XLFORUM |
| - | |The head may be larger than the original but it can be ground to fit with a bench grinder. ((photos by Jordan 1200 of the XLFORUM | + | |The head may be larger than the original but it can be ground to fit with a bench grinder. ((photos by Jordan 1200 of the XLFORUM |
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| - | |Measure the heads on the old and new plug, grind the new one if needed. ((photos by Jordan 1200 of the XLFORUM | + | |Measure the heads on the old and new plug, grind the new one if needed. ((photos by Jordan 1200 of the XLFORUM |
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| ===== Cutting New Threads for an Oversized Plug ===== | ===== Cutting New Threads for an Oversized Plug ===== | ||
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| * **First, clean the work area** so as to not induce outside trash / debris into the case. If there is trash in the threads, you can use a 90° angled pick to scraped them loose and cut a small piece of rag or panty hose to shove thru the middle of hole, pack it in and then turn counterclockwise and outward as in the pics above. Any loose debris within the hole can get shoved into the case with the next steps if not cleaned out first. | * **First, clean the work area** so as to not induce outside trash / debris into the case. If there is trash in the threads, you can use a 90° angled pick to scraped them loose and cut a small piece of rag or panty hose to shove thru the middle of hole, pack it in and then turn counterclockwise and outward as in the pics above. Any loose debris within the hole can get shoved into the case with the next steps if not cleaned out first. | ||
| * **Debris control**: | * **Debris control**: | ||
| - | * **Compressed air method**: Blow regulated air into the crankcase, adjust the air pressure so there' | + | * **Compressed air method**: Blow regulated air into the crankcase, adjust the air pressure so there' |
| - | * __On IH engines__, connect a regulated air hose to the crankcase breather. ((rivethog of the XLFORUM | + | * __On IH engines__, connect a regulated air hose to the crankcase breather. ((rivethog of the XLFORUM |
| * __On frame mount Evo engines__, this is a little more involved. The carburetor needs to come off to get the crankcase breather holes (one in each head). Either plug both of them with a 1/2" bolt, remove the cam cover vent at the oil tank and blow air into that hose. Or plug one of the breather holes and blow air into the other one. | * __On frame mount Evo engines__, this is a little more involved. The carburetor needs to come off to get the crankcase breather holes (one in each head). Either plug both of them with a 1/2" bolt, remove the cam cover vent at the oil tank and blow air into that hose. Or plug one of the breather holes and blow air into the other one. | ||
| - | * **Grease method**: Cover the case hole and drill bit with thick lube or grease to catch the chips. Inducing compressed air will not be effective while also using grease since the chips will be stuck in the grease and not blow out. These are aluminum shavings, not steel. The steel moving parts inside the engine should consume any minor amount of aluminum that does get in there. And it will come out with the next fluid changes. ((IronMick of the XLFORUM | + | * **Grease method**: Cover the case hole and drill bit with thick lube or grease to catch the chips. Inducing compressed air will not be effective while also using grease since the chips will be stuck in the grease and not blow out. These are aluminum shavings, not steel. The steel moving parts inside the engine should consume any minor amount of aluminum that does get in there. And it will come out with the next fluid changes. ((IronMick of the XLFORUM |
| * **Cut and stuff a small piece (3" - 4" long) of panty hose into the hole** prior to any work (between the flywheel and the case while allowing a small amount to be gotten to later with a pick). Make sure the material is not in the way of your work. You wouldn' | * **Cut and stuff a small piece (3" - 4" long) of panty hose into the hole** prior to any work (between the flywheel and the case while allowing a small amount to be gotten to later with a pick). Make sure the material is not in the way of your work. You wouldn' | ||
| * **Insert a 1/2" steel expansion plug (freeze plug)** into the hole for more protection and against the panty hose to keep from rolling the panty hose up on the bit and also to help guard against chips into the engine. This will allow the bit to spin against it instead of the nylon. Just make sure to grease the freeze plug also. | * **Insert a 1/2" steel expansion plug (freeze plug)** into the hole for more protection and against the panty hose to keep from rolling the panty hose up on the bit and also to help guard against chips into the engine. This will allow the bit to spin against it instead of the nylon. Just make sure to grease the freeze plug also. | ||
| - | * **Lube the drill / reamer bit**, especially in the flutes, with some thick assembly lube or grease. The grease on the bit should also help minimize snagging the material. You could also grease the panty hose but the dry material will probably catch and hold more debris. When the job is complete grab the panty hose with a hook pick and needle nose pliers (so you don't let go of the panty hose) and pull it out while turning it counterclockwise to help remove the chips from the threads. Any foreign material not already caught up in the threads should be stuck to the panty hose. ((Whitewalls of the XLFORUM | + | * **Lube the drill / reamer bit**, especially in the flutes, with some thick assembly lube or grease. The grease on the bit should also help minimize snagging the material. You could also grease the panty hose but the dry material will probably catch and hold more debris. When the job is complete grab the panty hose with a hook pick and needle nose pliers (so you don't let go of the panty hose) and pull it out while turning it counterclockwise to help remove the chips from the threads. Any foreign material not already caught up in the threads should be stuck to the panty hose. ((Whitewalls of the XLFORUM |
| ==== This Can Be Done with a Hand Drill or a Reamer ==== | ==== This Can Be Done with a Hand Drill or a Reamer ==== | ||
| - | |||
| * Either of which needs to run in straight or you'll end up with a leak. | * Either of which needs to run in straight or you'll end up with a leak. | ||
| - | * **The Colony oversized plug** has 11/ | + | * **The Colony oversized plug** has 11/ |
| * **Centering up**: In order to get a good seal on the new plug, the hole will have to be drilled or reamed straight with the existing hole center line. You can take your chances, eyeball it and hope for the best. But, it's better to use a 5/8" bushing pressed against the sealing edge of the hole with one hand while drilling / reaming through it with the other to keep the new hole from straying. | * **Centering up**: In order to get a good seal on the new plug, the hole will have to be drilled or reamed straight with the existing hole center line. You can take your chances, eyeball it and hope for the best. But, it's better to use a 5/8" bushing pressed against the sealing edge of the hole with one hand while drilling / reaming through it with the other to keep the new hole from straying. | ||
| * A standard 5/8" bushing has an O.D. of 7/8" (.875" | * A standard 5/8" bushing has an O.D. of 7/8" (.875" | ||
| * This may not be as big of an issue on pre-91 models due to the hole sitting higher up off the gear case. However, the hole sits low enough on 91-03 models that a bushing O.D. larger than the machined recess will cause the hole to be off center as the O.D. will rest on the gear case top and not low enough to center up. So, for these year cases (and prior years for safety), the O.D. of the bushing will need to be turned down (just enough to clear the outside of the case) to roughly match the recess unless you can find a thin walled 5/8" bushing. It's cheaper to take a standard bushing to a machine shop than to have them make one from scratch. | * This may not be as big of an issue on pre-91 models due to the hole sitting higher up off the gear case. However, the hole sits low enough on 91-03 models that a bushing O.D. larger than the machined recess will cause the hole to be off center as the O.D. will rest on the gear case top and not low enough to center up. So, for these year cases (and prior years for safety), the O.D. of the bushing will need to be turned down (just enough to clear the outside of the case) to roughly match the recess unless you can find a thin walled 5/8" bushing. It's cheaper to take a standard bushing to a machine shop than to have them make one from scratch. | ||
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| === Drilling the Hole === | === Drilling the Hole === | ||
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| ===== Tapping Threads for a Bigger Plug ===== | ===== Tapping Threads for a Bigger Plug ===== | ||
| - | * You can re-thread the case hole with a 1/4" NPT pipe tap and change to a regular pipe plug. ((MTD of the XLFORUM | + | * You can re-thread the case hole with a 1/4" NPT pipe tap and change to a regular pipe plug. ((MTD of the XLFORUM |
| * This '71 XLCH case was tapped for a M20 X 1.5 drain plug. | * This '71 XLCH case was tapped for a M20 X 1.5 drain plug. | ||
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| - | | Aftermarket drain plug on a '71 XLCH ((phot by Whitewalls of the XLFORUM | + | | Aftermarket drain plug on a '71 XLCH ((phot by Whitewalls of the XLFORUM |
| ===== Installing Thread Inserts ===== | ===== Installing Thread Inserts ===== | ||
