What is correct cam end play for Gen VI, and how do you set it?
02-11-2013, 10:22 PM
#11
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On mine thats the end play i have when the gear set was new, now i have .010'' after 80 hours of running dont know if is that too much, the extra end play that i have come from the torrington trust bearing.
02-12-2013, 10:35 PM
#15
Everything is new, but cam gear has 30 hours on it.
Checked it again with the cam gear installed and torqued, and now I have ZERO play. My cam gear does have the built in Torrington thrust bearing, so maybe that is by design, but I was expecting it to have a few thousandths.
Checked it again with the cam gear installed and torqued, and now I have ZERO play. My cam gear does have the built in Torrington thrust bearing, so maybe that is by design, but I was expecting it to have a few thousandths.
02-13-2013, 10:10 PM
#16
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sorry ive never used the Torrington in a gen 5 or 6 so im not sure if .000 is enough end play i would think .002 or .003. I allways hse the stock thrust plate and have no problems good luck...
02-13-2013, 10:50 PM
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Everything is new, but cam gear has 30 hours on it.
Checked it again with the cam gear installed and torqued, and now I have ZERO play. My cam gear does have the built in Torrington thrust bearing, so maybe that is by design, but I was expecting it to have a few thousandths.
Checked it again with the cam gear installed and torqued, and now I have ZERO play. My cam gear does have the built in Torrington thrust bearing, so maybe that is by design, but I was expecting it to have a few thousandths.
I remember mine when it was new at .003'' i canot fell the end play by hand you nead a dial gauge to see them.
Also on mine i open up a litle the cam edge plate dia because the gear does not turn freely when torque in place due to the rear retaining bearing ring (you can see them in the iner side dia of the bearing near the bearing cover) was a litle thicker then the bearing, that is was cause the 0 end play and the restriction if you heve one when you turn the gear by hand.
Thats a trust bearing and you need .003-.005'' end play, if they are too tight it wont last.
Sorry i dont have anny pic to show you what i am trying to explain hope thats can help you
02-14-2013, 08:31 AM
#18
Super MX,
The cam does turn freely, but I can feel a little bit of resistance when I turn it. This seems to be the case whether or not the gear is installed and torqued down, so I don't think it is because of the gear / torrington bearing. I pulled the cam back out and inspected it, and all seems fine there - cam journals don't have any burrs or high spots. Temp in my garage is about 45*, so it may just be the fact that the assembly lube is thick. I don't feel any binding at all when I turn it, just a little drag - in other words, it's not like you can just spin it and take your hand on it and it will continue to move. You have to continue to apply a little bit of force - maybe a foot lb or two at most. Probably normal - I talked to Bob Madera about it yesterday and he said he doesn't think I have a problem. He said in general you don't even have to check end play with a Gen VI cam retaining system.
I wish I had another cam handy to compare it to. What would really be nice would be to have the old cam that I was running before - it ran with the same timing gear for 30 hours with no issues at all. That would be a good comparison to make.
I'm probably way overthinking this whole thing, but it's the little things like this that keep me up at night.
The cam does turn freely, but I can feel a little bit of resistance when I turn it. This seems to be the case whether or not the gear is installed and torqued down, so I don't think it is because of the gear / torrington bearing. I pulled the cam back out and inspected it, and all seems fine there - cam journals don't have any burrs or high spots. Temp in my garage is about 45*, so it may just be the fact that the assembly lube is thick. I don't feel any binding at all when I turn it, just a little drag - in other words, it's not like you can just spin it and take your hand on it and it will continue to move. You have to continue to apply a little bit of force - maybe a foot lb or two at most. Probably normal - I talked to Bob Madera about it yesterday and he said he doesn't think I have a problem. He said in general you don't even have to check end play with a Gen VI cam retaining system.
I wish I had another cam handy to compare it to. What would really be nice would be to have the old cam that I was running before - it ran with the same timing gear for 30 hours with no issues at all. That would be a good comparison to make.
I'm probably way overthinking this whole thing, but it's the little things like this that keep me up at night.
Last edited by Budman II; 02-14-2013 at 08:39 AM.
02-14-2013, 11:24 AM
#19
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Super MX,
The cam does turn freely, but I can feel a little bit of resistance when I turn it. This seems to be the case whether or not the gear is installed and torqued down, so I don't think it is because of the gear / torrington bearing. I pulled the cam back out and inspected it, and all seems fine there - cam journals don't have any burrs or high spots. Temp in my garage is about 45*, so it may just be the fact that the assembly lube is thick. I don't feel any binding at all when I turn it, just a little drag - in other words, it's not like you can just spin it and take your hand on it and it will continue to move. You have to continue to apply a little bit of force - maybe a foot lb or two at most. Probably normal - I talked to Bob Madera about it yesterday and he said he doesn't think I have a problem. He said in general you don't even have to check end play with a Gen VI cam retaining system.
I wish I had another cam handy to compare it to. What would really be nice would be to have the old cam that I was running before - it ran with the same timing gear for 30 hours with no issues at all. That would be a good comparison to make.
I'm probably way overthinking this whole thing, but it's the little things like this that keep me up at night.
The cam does turn freely, but I can feel a little bit of resistance when I turn it. This seems to be the case whether or not the gear is installed and torqued down, so I don't think it is because of the gear / torrington bearing. I pulled the cam back out and inspected it, and all seems fine there - cam journals don't have any burrs or high spots. Temp in my garage is about 45*, so it may just be the fact that the assembly lube is thick. I don't feel any binding at all when I turn it, just a little drag - in other words, it's not like you can just spin it and take your hand on it and it will continue to move. You have to continue to apply a little bit of force - maybe a foot lb or two at most. Probably normal - I talked to Bob Madera about it yesterday and he said he doesn't think I have a problem. He said in general you don't even have to check end play with a Gen VI cam retaining system.
I wish I had another cam handy to compare it to. What would really be nice would be to have the old cam that I was running before - it ran with the same timing gear for 30 hours with no issues at all. That would be a good comparison to make.
I'm probably way overthinking this whole thing, but it's the little things like this that keep me up at night.
But on mine i was feel more restriction when the gear was torqued on vs non torqued. So thats why i have work a litle the cam retening plate due to the imperfection of the torrignton bearing.
If you have already run 30h with that gear and cam you are probably ok.
Just make sure you have no differrance when the gear is on non torqued vs the gear torqued on.
02-15-2013, 09:28 PM
#20
Measurements
I still wasn't quite convinced that I don't have an issue, so I set my mind to trying to get some answers. First thing I wanted to do was figure out what timing set I have. After some investigation, it looks like it is the same thing as the ones that Summit and Jegs both carry under their house names. For example, the one Summit lists is PN SUM-G6617-B => http://www.summitracing.com/parts/su...b/media/images
It is a double roller set that has an entrained thrust bearing built into the back of the gear.
Jegs also sells one under PN 20425. Jegs tech support couldn't really tell me much about required end play for their sets, but the guy at Summit claimed that these were designed to be run with zero end play. I wasn't completely satisfied, so I took it by a local speed shop that builds a lot of racing engines. His opinion was that at zero end play, you don't really have any way of ensuring that there is no excessive preload on the bearing, which could lead to failure. He thought I should have 0.002 or 0.003 at least.
So I took my micrometer out in the garage and took some measurements.
First I measured the depth of the nose of the cam protruding from the retainer. I got 0.115".
Next I measured the depth from the face of the torrington bearing to the surface of the gear that rides on the nose of the cam. For this I got 0.120".
That would indicate that I actually have about 0.005" PRELOAD on the bearing.
Just for grins, I took another measurement of the depth of the back of the gear that mounts on the nose of the cam, and got 0.107". I laid a straight edge across the face of the thrust bearing and slid a feeler gauge, and it sits between 0.002 and 0.003 above the edge of the gear. So that should give me a total stacked distance of about 0.109 - 0.110. Theoretically, that should show up as about 0.005 end play, so I am a little confused by this measurement.
I am going to try mounting a different timing gear on the cam that is in the engine, and I am also going to try a different Gen VI cam just for grins to see if I can isolate the problem.
It is a double roller set that has an entrained thrust bearing built into the back of the gear.
Jegs also sells one under PN 20425. Jegs tech support couldn't really tell me much about required end play for their sets, but the guy at Summit claimed that these were designed to be run with zero end play. I wasn't completely satisfied, so I took it by a local speed shop that builds a lot of racing engines. His opinion was that at zero end play, you don't really have any way of ensuring that there is no excessive preload on the bearing, which could lead to failure. He thought I should have 0.002 or 0.003 at least.
So I took my micrometer out in the garage and took some measurements.
First I measured the depth of the nose of the cam protruding from the retainer. I got 0.115".
Next I measured the depth from the face of the torrington bearing to the surface of the gear that rides on the nose of the cam. For this I got 0.120".
That would indicate that I actually have about 0.005" PRELOAD on the bearing.
Just for grins, I took another measurement of the depth of the back of the gear that mounts on the nose of the cam, and got 0.107". I laid a straight edge across the face of the thrust bearing and slid a feeler gauge, and it sits between 0.002 and 0.003 above the edge of the gear. So that should give me a total stacked distance of about 0.109 - 0.110. Theoretically, that should show up as about 0.005 end play, so I am a little confused by this measurement.
I am going to try mounting a different timing gear on the cam that is in the engine, and I am also going to try a different Gen VI cam just for grins to see if I can isolate the problem.
