Well, it ate another distributor gear....
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
Well, it ate another distributor gear....
At least this time I didn't drive it...:mad:
Ran it for 20 minutes or so so I could bleed the cooling system.
Decided to pull the dist. and check it out.
Sure enough it was chewing into the bottom 3/8" of the gear....
I'm going back and fourth trying to figure out why on earth its doing this.
Nothing is "raised" from stock, I had absolutely no problems with my previous HR cam.
This SR has a cast gear for use with a cast dist gear.
I DO have a LOT of oil pressure: 80+lbs cold, 75lbs hot cruising 3000rpm.
40lbs idle. (900-1000rpm)
I'm not sure what to do next, looks like it may end up sitting for a while. :'(
Thanks for any suggestions.
:cheers:
Ran it for 20 minutes or so so I could bleed the cooling system.
Decided to pull the dist. and check it out.
Sure enough it was chewing into the bottom 3/8" of the gear....
I'm going back and fourth trying to figure out why on earth its doing this.
Nothing is "raised" from stock, I had absolutely no problems with my previous HR cam.
This SR has a cast gear for use with a cast dist gear.
I DO have a LOT of oil pressure: 80+lbs cold, 75lbs hot cruising 3000rpm.
40lbs idle. (900-1000rpm)
I'm not sure what to do next, looks like it may end up sitting for a while. :'(
Thanks for any suggestions.
:cheers:
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
Re: Well, it ate another distributor gear.... (ld85)
No, I used another MSD iron gear. The melonized gear has the wrong shaft diameter (stock chevy .49x"?). For some reason MSD thinks they need .500" shafts. :confused:
The weird thing is, is that it is just doing it to the bottom of the gear, like its not far enough in, OR maybe the cam is walking too far? I noticed ~1/16" of endplay....is this WAY to much?
Thanks!
I got frustrated enough tonight to just leave it alone. I've spend the rest of the night working on a '96 Neon 2L SOHC. I have to take the head off and get it repaired (read: broken timing belt).
I certainly enjoy working on "old tech" a LOT better! :lol:
Add that to the fact that my '93 lincoln continental blew a head gasket and decided to drain antifreeze out the mufflers and I have had HORRIBLE automobile luck in the last month.
:mad
Any suggestions?
The weird thing is, is that it is just doing it to the bottom of the gear, like its not far enough in, OR maybe the cam is walking too far? I noticed ~1/16" of endplay....is this WAY to much?
Thanks!
I got frustrated enough tonight to just leave it alone. I've spend the rest of the night working on a '96 Neon 2L SOHC. I have to take the head off and get it repaired (read: broken timing belt).
I certainly enjoy working on "old tech" a LOT better! :lol:
Add that to the fact that my '93 lincoln continental blew a head gasket and decided to drain antifreeze out the mufflers and I have had HORRIBLE automobile luck in the last month.
:mad
Any suggestions?
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Re: Well, it ate another distributor gear.... (VETDRMS)
Two thoughts. First, that IS a lot of play for a roller cam. It should be more like .008"-.010". BUT, I don't think that is wearing out gears.
Second, have you changed intake manifolds in the process? Is the distributor new? Because you are losing only the bottom of the gear, makes me think the distributor is riding too high in the engine. A new manifold, particularly, can cause that. Some performance distributors have an adjustable collar that locates the distributor on the manifold, to set the depth, for that very reason.
On the gear. I bet it wouldn't be a major operation to bore a gear to .500".
As an after thought, all that great oil pressure does put an extra load on the distributor gear. Good luck, and...
RACE ON!!!
[Modified by CFI-EFI, 9:00 AM 4/3/2004]
Second, have you changed intake manifolds in the process? Is the distributor new? Because you are losing only the bottom of the gear, makes me think the distributor is riding too high in the engine. A new manifold, particularly, can cause that. Some performance distributors have an adjustable collar that locates the distributor on the manifold, to set the depth, for that very reason.
On the gear. I bet it wouldn't be a major operation to bore a gear to .500".
As an after thought, all that great oil pressure does put an extra load on the distributor gear. Good luck, and...
RACE ON!!!
[Modified by CFI-EFI, 9:00 AM 4/3/2004]
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
Re: Well, it ate another distributor gear.... (CFI-EFI)
No, its a not a bronze gear and it doesn't require one (cast cam gear)
CFI-EFI This is the same distributor and the same intake that I put nearly 2500 miles on with my HR cam, no wear issues.
The only difference is the cam...
CFI-EFI This is the same distributor and the same intake that I put nearly 2500 miles on with my HR cam, no wear issues.
The only difference is the cam...
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Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
Re: Well, it ate another distributor gear.... (CFI-EFI)
CFI-EFI Yes, I too am afraid its the cam. I can see some wear on the teeth so it looks like its coming back out. :( I reset the distributor tonight without a gasket and kind of moved it over a bit and ran it for 2-3 minutes. Took it out and it was digging pretty bad into one side only. Sounds to me like the cam gear is non-concentric.
What kind of recourse do I have? As far as warranty goes, is Comp usually pretty good about this stuff? I bought it through summit so at the very least I'm sure I could get it RMA-ed.
Do you think any of the debris did any damage anywhere?
Thank you all for all your help, much appreciated.
:cheers:
What kind of recourse do I have? As far as warranty goes, is Comp usually pretty good about this stuff? I bought it through summit so at the very least I'm sure I could get it RMA-ed.
Do you think any of the debris did any damage anywhere?
Thank you all for all your help, much appreciated.
:cheers:
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
Re: Well, it ate another distributor gear.... (VETDRMS)
CFI-EFI No, the heads are the same (AFR), the only work I had done was port work. They were also flat milled .006", just enough to clean the deck surface.
I did lower the quench by .010" by using a set of Cometic .030" gaskets.
Other than those two things: .036" lower, no changes.
Some good news: I got the head pulled off my 2.0L SOHC Neon and after 100,000+ miles you can still see the cross-hatch on the cylinders and there is only light scuffing from the skirts. Their are however little eyebrows where the valves kissed the pistons when the timing belt let go. Also the belt was a mess, it looks as if it was pulling of teeth one by one for some time now. I'm sure that explains some of the issues it was having. But, all-in-all it looks good and I'm taking the head in for repairs this week :yesnod:
I am not looking forward to putting it back together however, disassembly was less then enjoyable.
:cheers:
I did lower the quench by .010" by using a set of Cometic .030" gaskets.
Other than those two things: .036" lower, no changes.
Some good news: I got the head pulled off my 2.0L SOHC Neon and after 100,000+ miles you can still see the cross-hatch on the cylinders and there is only light scuffing from the skirts. Their are however little eyebrows where the valves kissed the pistons when the timing belt let go. Also the belt was a mess, it looks as if it was pulling of teeth one by one for some time now. I'm sure that explains some of the issues it was having. But, all-in-all it looks good and I'm taking the head in for repairs this week :yesnod:
I am not looking forward to putting it back together however, disassembly was less then enjoyable.
:cheers:
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Re: Well, it ate another distributor gear.... (VETDRMS)
I did lower the quench by .010" by using a set of Cometic .030" gaskets.
Other than those two things: .036" lower, no changes.
Other than those two things: .036" lower, no changes.
RACE ON!!!
[EDIT] On second thought, maybe it doesn't raise the manifold. At a minimum, the heads are lowered in relation to the manifold, and that can throw the port alignment off. If you were to shave the intake side of the heads or the manifold, that would drop it back down lower into the "vee" to realign the ports. THAT would drop the distributer, also. Ask your machinist.
[Modified by CFI-EFI, 9:33 AM 4/4/2004]
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Well, it ate another distributor gear.... (VETDRMS)
I had problems with my roller cam eating distributor gears too so I emailed Comp Cams and they told me my cam needed the hard RC60 stock chevy distributor gear. I have tested a number of gears and most are in the RC 20-30 range but GM also has a hard 60 gear and it worked. After 3 years of running it looks great. I ordered it from the local chevy dealer,
Thread Starter
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
Re: Well, it ate another distributor gear.... (CFI-EFI)
CFI-EFI Thanks, I made a typo and it has only been "lowered" by .016" not .030". Something without a doubt is amiss, I have gotten quite good at pulling the motor and can have it out in an hour and half now. :lol:
Norval
Did your comp rollers have the cast gear? I'm assuming the RC60 gear is the "melonized" gear? I may try that and see how it does, at $24 its worth a shot and may save me from pulling it out. The cam gear does have some "shiny" color on the gear, but It doesn't look worn down.
If push came to shove the cam gear would obliterate the distributor gear, no?
Thanks again!
Norval
Did your comp rollers have the cast gear? I'm assuming the RC60 gear is the "melonized" gear? I may try that and see how it does, at $24 its worth a shot and may save me from pulling it out. The cam gear does have some "shiny" color on the gear, but It doesn't look worn down.
If push came to shove the cam gear would obliterate the distributor gear, no?
Thanks again!
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Well, it ate another distributor gear.... (VETDRMS)
They want the distributor gear to go before the cam gear but the 2 must be close or one will chew the other. If the distributor gear is being eaten then they are not close enough and you need a harder gear.
I had a severe problem with a built 355, it ate gears in a few miles but once I went to a hardened gear all problems went away.
I had a severe problem with a built 355, it ate gears in a few miles but once I went to a hardened gear all problems went away.
