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Atolduso

Cam cap bolt doesn't want to go all the way down...

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I haven't run into this before and hoping someone can help here, I know there are two significantly longer bolts for the chain cover thing and those are in the right spot. All the others are the same size though correct?

This bolt unlike the others will not allow me to finger tighten it down, and with an allen key with light pressure it already has a good amount of resistance before it even seats, like its bottoming out. I obviously don't want to force anything so I figured I'd ask here and see what others think, it definitely doesn't seem right as it is currently. 

 

 

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Edited by Atolduso

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Next break loose each of the cam cap bolts in a criss cross pattern, taking note of the position of each one. You will find two different lengths, two long, 6 short. If you mix up the position later upon install and put a short one in a long hole you will pull out (strip) the threads when you try and tighten it down.

 

 

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Take it apart, make sure you do have the long bolts in the right places (fwd right side).  Make sure there is no crap in the bottom of the hole. Check all the bolts for damage (stretched threads).  Now the hard part.  Bottom tap all the holes.  You can gain quite a few additional threads in all of the cam cap bolt holes. Clean chips out of the freshly tapped holes.  Go buy longer bolts to take advantage of the additional threads in all of the holes.  You may have to custom trim the bolts to take advantage of all the threads without bottoming in the holes.  Of course you can do just the 1 hole in question but why no do all of them for good measure.

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Okay great thanks folks. I ran a tap through it and its fine now. Long bolts were in the right spots. Covered the head and blew it out with brake clean, it seems fine. It must have some bad threads or just some grit in there, but I have tightened it down without issue so I'm not going to worry about it much. 

It's an old bike that has been through several valve adjustments and cam chain changes so who knows. 

Edited by Atolduso
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19 hours ago, Noble said:

Take it apart, make sure you do have the long bolts in the right places (fwd right side).  Make sure there is no crap in the bottom of the hole. Check all the bolts for damage (stretched threads).  Now the hard part.  Bottom tap all the holes.  You can gain quite a few additional threads in all of the cam cap bolt holes. Clean chips out of the freshly tapped holes.  Go buy longer bolts to take advantage of the additional threads in all of the holes.  You may have to custom trim the bolts to take advantage of all the threads without bottoming in the holes.  Of course you can do just the 1 hole in question but why no do all of them for good measure.

This should be at the very bottom of the possible solutions.  Risk of damage due to chips or a broken tap is just not worth the risk since a simpler solution must exist. If the bike was together when you got it follows that something you have done has caused the incorrect fit. Find it!  I would take all the bolts out and then set them back in the holes with zero engagement of the threads.  The distance from the mating surface to the bottom of the flange on the bolt should be equal for all the bolts.  Play mix and match to get the bolts into the correct holes.  

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Well you have your opinion, I have mine.  Have you ever actually repaired stripped cam cap threads?  I have and the recommended approach works extremely well and can often prevent the need for Helicoil repairs.  The fact is repeated tightening of the cam cap bolts to spec or near or above spec can cause the threads to fail. Getting more threads prior to actual stripping is work but less work than repair later on. Unless ham fisted, breaking a tap us unlikely.  The tap drill hole is already there it just needs more threads. M6x1,0 bottom taps are sturdy enough I don't think breakage is a big concern.  Air or even WD40 will blow the chips out of the holes and some care with rags will keep chips out of the motor.  But maybe it is more about what I'm comfortable doing than what others are. Obviously it is a choice.

What is the simpler solution? Put the bolts on the correct places? OP said he already did that. I have to accept that he did and suggested he verify that first.

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While I didn't make any "new" threads further down, the tap method cleaned out the existing mess and fixed my issue, so I would say it was a great method!

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On 12/3/2018 at 4:03 PM, Noble said:

Well you have your opinion, I have mine.  Have you ever actually repaired stripped cam cap threads?  I have and the recommended approach works extremely well and can often prevent the need for Helicoil repairs.  The fact is repeated tightening of the cam cap bolts to spec or near or above spec can cause the threads to fail. Getting more threads prior to actual stripping is work but less work than repair later on. Unless ham fisted, breaking a tap us unlikely.  The tap drill hole is already there it just needs more threads. M6x1,0 bottom taps are sturdy enough I don't think breakage is a big concern.  Air or even WD40 will blow the chips out of the holes and some care with rags will keep chips out of the motor.  But maybe it is more about what I'm comfortable doing than what others are. Obviously it is a choice.

What is the simpler solution? Put the bolts on the correct places? OP said he already did that. I have to accept that he did and suggested he verify that first.

It doesn't matter if you have done a hundred of the taps jobs or if I have.  The question is does Atolduso feel comfortable doing the operation.  Since he needs help knowing what to do I believe he has not been busy tapping blocks in his spare time.  His was not the type of question you would ask if you don't have the experience. 

Edited by arc2arc

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  The first thing to check for is dirt or something else in the hole.     Everytime you screw in the bolt you push some more stuff into the hole it needs to be cleaned out every now and then.

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16 hours ago, arc2arc said:

It doesn't matter if you have done a hundred of the taps jobs or if I have.  The question is does Atolduso feel comfortable doing the operation.  Since he needs help knowing what to do I believe he has not been busy tapping blocks in his spare time.  His was not the type of question you would ask if you don't have the experience. 

And yet he listened to the suggestion made, accomplished the task with ease and had the outcome expected.
Serviceable threads no broken taps...because, its not that hard to do right, and very hard to do wrong.

No one was recommending he tig weld the old hole, drill and tap a new one aligned perfectly with the previous one.. Now that would be a bad recommendation for someone who did not have the experience and tools on hand.

Anyone that can screw in a light bulb can run a tap down an existing threaded hole, it is about as basic an operation as can be... And yes, there are some that should not attempt even that basic task having no ability natural or learned. No patience, and no desire to find some... ... they also should not have the cam caps off, or the valve cover, or the seat and tank....but that is not this..

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20 hours ago, Barry Ries said:

  The first thing to check for is dirt or something else in the hole.     Everytime you screw in the bolt you push some more stuff into the hole it needs to be cleaned out every now and then.

Will be doing that in the future for sure! Honestly junk in the threads is something I would have expected in a external hole like the header bolt, but in a clean environment like the head I didn't expect it to be bad. You are right it collected at the bottom. 

The only reason I have a full tap and die kit is because I'd had to use it maybe 5 times on my DRZ. 

Edited by Atolduso

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51 minutes ago, Atolduso said:

Will be doing that in the future for sure! Honestly junk in the threads is something I would have expected in a external hole like the header bolt, but in a clean environment like the head I didn't expect it to be bad. You are right it collected at the bottom. 

The only reason I have a full tap and die kit is because I'd had to use it maybe 5 times on my DRZ. 

  More often than not a dirty bolt hole can be cleaned out with a small screw driver and liberal use of WD 40.  But I also have a nice tap and die set because when you need them,  you really need them. 

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18 hours ago, Atolduso said:

Will be doing that in the future for sure! Honestly junk in the threads is something I would have expected in a external hole like the header bolt, but in a clean environment like the head I didn't expect it to be bad. You are right it collected at the bottom. 

The only reason I have a full tap and die kit is because I'd had to use it maybe 5 times on my DRZ. 

For those that don't know... there are many different types of taps, both in design and clearance , oversize and undersizes. Just a few common tap types are; 

  1. Thread cutting these are what most people will buy in store and online by default.,
  2. Thread forming  (think displaced metal, not removed)
  3. Thread chasing used to clean up a pre existing threaded hole with out undercutting existing threads. 


Running a thread cutting tap into a hole with damaged threads, the tap will cut though and across the damaged threads.... .
Using a thread cutting tap in a threaded hole that has galling or material from a damaged fastener, silicone or gasket garbage,  might be the better solution as the tap will "cut out" the material from the threads.
If the threads are just deformed, a thread forming tap or thread chasing tap might be the better option as they tend to "re-form" the threads back in shape vice just cutting through and across them leaving you with a less strong threaded hole. 

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I concur with Erik. I suggest one buy a thread restorer kit before investing in a tap and die kit.  Most home mechanics will need one many times more often than a true cutting tap and die.

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On 12/6/2018 at 1:45 PM, Atolduso said:

Will be doing that in the future for sure! Honestly junk in the threads is something I would have expected in a external hole like the header bolt, but in a clean environment like the head I didn't expect it to be bad. You are right it collected at the bottom. 

The only reason I have a full tap and die kit is because I'd had to use it maybe 5 times on my DRZ. 

if the hole has oil in the bottom it can stop the bolt hydraulically. I'm betting you blew it out with brake clean and it was ready then

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1 hour ago, ohgood said:

if the hole has oil in the bottom it can stop the bolt hydraulically. I'm betting you blew it out with brake clean and it was ready then

Good point, happens a lot with frame in motor top end jobs....and head bolts.... Clean your holes ....lol

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   If you are economically challenged, stuck somewhere without access to your good tools, or just cheap you can take a bolt and cut a groove along one side of the threads, then run a new nut up and down the threads a few times to straighten out the threads.       Now you can take the altered bolt and screw it into the hole, the stuff that is stuck in the threads and at the bottom of the hole collects in the groove and comes out of the hole.   

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20 hours ago, Barry Ries said:

   If you are economically challenged, stuck somewhere without access to your good tools, or just cheap you can take a bolt and cut a groove along one side of the threads, then run a new nut up and down the threads a few times to straighten out the threads.       Now you can take the altered bolt and screw it into the hole, the stuff that is stuck in the threads and at the bottom of the hole collects in the groove and comes out of the hole.   

It does work.... done it  many times for an odd thread hole I did not have a bottoming tap for at the time...

Its only for clearing dirt, silicone, ect from the hole.. not rehabbing threads.
Suggest you use a grade 8 fastener if you have one, run a grade 8 nut all the way up to the top before cutting the groove wither you use a grade 8 fastener or not (1/16" to 1/8" cut off wheel makes a nice groove., small triangle file works as well) If you have a thread file, run it across the fastener threads before you run the nut down.

Use your home made thread chaser by hand only...feel for the groove to pack up and the chaser to turn harder STOP..back it out now and clean the junk from the groove, use some more light lube in the threaded hole and run the chaser down again. 

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48 minutes ago, jjktmrider said:

Metric fasteners come in 8.8, 9.8 ,10.9 and 12.9 grades . Hold the cutoff wheel at an angle going up the bolt to make a positive relief and it'll cut fairly good as well .

 

.

Yes of course, good point and common SAE fasteners use non graded though grade 8 and metric commonly use non graded through  12.9  I felt clearly the take away was not metric and its grading or SAE and its grading ...it was use a harder grade... Sorry I thought that was clear, but perhaps not to all. 

And really there are many more marked grades of fasteners then just 8.8, 9.8 ,10.9 and 12.9 or SAE 2, 5, and 8
8.8, 9.8 ,10.9 and 12.9. And of course don't forget about ATSM fastener standards ..lol or Specialty fasteners from the likes of ARP that are not standardized in "grade" 
 

Quote

ARP manufactures fasteners from a wide assortment of materials ranging from popular stainless steel and 8740 chrome moly to exotic alloys that have been developed to handle space travel. 

You should also know that there are grades within specific alloys. For example, 8740 is available in four grades: 
1. SDF (guaranteed seamless and defect free).
2. CHQ (cold head quality). 
3. Aircraft. 
4. Commercial. 

ARP uses only the first two (SDF and CHQ), even though they cost more than double “Aircraft” quality.

STAINLESS STEEL: Ideally suited for many automotive and marine applications because stainless is tolerant of heat and virtually impervious to rust and corrosion. ARP “Stainless 300” is specially alloyed for extra durability. It’s polished using a proprietary process to produce a beautiful finish. Tensile strength is typically rated at 170,000 psi.

8740 CHROME MOLY: Until the development of today’s modern alloys, chrome moly was popularly considered a high strength material. Now viewed as only moderate strength, 8740 chrome moly is seen as a good tough steel, with adequate fatigue properties for most racing applications, but only if the threads are rolled after heat-treatment, as is the standard ARP production practice. Typically, chrome moly is classified as a quench and temper steel, that can be heat-treated to deliver tensile strengths between 180,000 and 210,000 psi.

ARP2000®: An exclusive, hybrid-alloy developed to deliver superior strength and better fatigue properties. While 8740 and ARP2000 share similar characteristics – ARP2000 is capable of achieving clamp loads in the 215,000-220,000 psi range. ARP2000 is used widely in short track and drag racing as an up-grade from 8740 chrome moly in both steel and aluminum rods. Stress corrosion and hydrogen embrittlement are typically not a problem, providing care is taken during installation.

L19: This is a premium steel that is processed to deliver superior strength and fatigue properties. L19 is a very high strength material compared to 8740 and ARP2000 and is capable of delivering clamp loads in the 230,000-260,000 psi range. It is primarily used in short track and drag racing applications where inertia loads exceed the clamping capability of ARP2000. Like most high strength, quench and temper steels – L19 requires special care during manufacturing to avoid hydrogen embrittlement. This material is easily contaminated and subject to stress corrosion. It must be kept well-oiled and not exposed to moisture.

AERMET® 100: With a typical tensile strength of 280,000 psi, Aermet 100 is a new martensitic super-alloy that is stronger and less expensive than the super-alloy austenitic materials that follow. Because it is capable of achieving incredibly high clamping loads, it is ideal for short but extreme environments like top fuel, funny car and some short track applications. Although Aermet 100 is a maraging steel that is far superior to other high strength steels in its resistance to stress corrosion, it must be kept well-oiled and not exposed to moisture.

INCONEL 718: A nickel based material that is in the high temperature, super-alloy class, it is found to be equally suitable in lower temperature applications. This material delivers tensile strengths into the 220,000 psi range and exhibits improved fatigue properties. Best of all, Inconel 718 is completely immune to hydrogen embrittlement and corrosion.

ARP3.5® (AMS5844): While similar to Inconel 718, these super-alloys are found in many jet engine and aerospace applications where heat and stress attack the life of critical components. The high cobalt content of this alloy, while expensive, delivers a material with superior fatigue characteristics and typically tensile strength in the 270,000 psi range. The immunity to hydrogen embrittlement and corrosion of these materials is a significant design consideration. These materials are primarily used in connecting rods where extremely high loads, high RPM and endurance are important factors – Formula 1, Winston Cup and CART applications.

CUSTOM AGE 625 PLUS®: This newly formulated super-alloy demonstrates superior fatigue cycle life, tensile strength and toughness – with complete resistance to atmospheric corrosion and oxidation. ARP is the first to develop manufacturing and testing processes for fasteners with Custom Age 625+. Best of all it is less expensive and expected to soon replace MP-35 as the material of choice in the high strength, super-alloy field. Typical tensile strength is 260,000 psi.

TITANIUM: ARP now offers special order fasteners made of an alloy (Ti6Al-4V) that is specially heat-treated (a process developed by ARP’s own Russ Sherman) and provides superior strength to other titanium alloys employed in racing and aerospace. The material has a nominal tensile strength of 180,000 psi, and is very corrosion resistant. The main advantage of titanium, of course, is its weight – which is about 40% lighter than a comparable fastener made of steel. Head studs and accessory bolts are ideal applications for this lightweight material.


http://www.americanfastener.com/wp-content/uploads/2013/11/American-Fastener-Tables.pdf

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