Cam break in issue
Thread Starter
Drifting
Joined: Dec 2004
Posts: 1,714
Likes: 42
From: Austin Texas
Cam break in issue
Tonight I set out to perform my new cam break-in. I was being so very careful. For the lube I still had some of the thick black breakin lube, I used Crower Cam saver lifters and Joe Gibbs BR oil. Preset the timing advance and it started right away and a buddy was keeping the rpm at around 2k.
The problem is that 5 minutes in to the process an oil leak developed at the base of the fancy two piece timing cover I just installed. I tried to tighten it and coax a seal but it wasnt going to happen. So, I shut it down.
My question is what would you have done? and or have I made an error in the break in? Over the 20 min break in I would have probably leaked half a quart or so and didnt want to risk it. My intention is to repair the leak and resume the break in procedure.
The problem is that 5 minutes in to the process an oil leak developed at the base of the fancy two piece timing cover I just installed. I tried to tighten it and coax a seal but it wasnt going to happen. So, I shut it down.
My question is what would you have done? and or have I made an error in the break in? Over the 20 min break in I would have probably leaked half a quart or so and didnt want to risk it. My intention is to repair the leak and resume the break in procedure.
Pro
Joined: Jul 2010
Posts: 691
Likes: 25
From: Boynton Beach Florida
Your doing exactly what is recommended. Leaks and other problems can arise with a fresh start up. I have always heard and was taught in automotive school if something comes up shut it down, don't idle it down just stop the engine rotation. Find the problem, fix it then start it up and resume 2-2400 rpm break in. The rpm is of most importance since that is the only way oil will splash off the crankshaft counter weights to lube the cam while the new metal materials are wearing against each other.
When I installed my cam a year ago I didn't have a torque converter cover so I installed a nice chrome one. As soon as I started the car the most God awful noise was heard, naturally I'm thinking I royally screwed something up but once my nerves settle a little bit I figured out it had to be the inspection cover. I shut the engine off, got under the car and ripped that thing out and started it back up, problem solved, finished the break in and everything has been smooth sailing since then.
When I installed my cam a year ago I didn't have a torque converter cover so I installed a nice chrome one. As soon as I started the car the most God awful noise was heard, naturally I'm thinking I royally screwed something up but once my nerves settle a little bit I figured out it had to be the inspection cover. I shut the engine off, got under the car and ripped that thing out and started it back up, problem solved, finished the break in and everything has been smooth sailing since then.
Thread Starter
Drifting
Joined: Dec 2004
Posts: 1,714
Likes: 42
From: Austin Texas
Here is another factor then, it is probably going to be a few days before I can make the repair and continue the break in. I guess I don't really have much of a choice at this point.
Pro
Joined: Jul 2010
Posts: 691
Likes: 25
From: Boynton Beach Florida
Well, luckily the cam can't tell time. In theory the cam lube is sticky and stays on the cam during most of the break-in. The only thing you can really do for peace of mind would be pull the distributor and using a homemade tool or the Moroso primer tool to spin the oil pump for a few minutes to bring some oil to the cam journals.
Truthfully if you ran it for at least 5 minutes and get it fixed in a few days with the fact that it fired up immediately I would get it started again and immediately get the idle speed screw on the carb up to rpm and let it finish up. I'm certainly not making light of the importance of the cam break-in procedure but I do believe there has been a certain amount of over hipe put into these things by the cam makers to help cover them.
If you think about it, when you removed the old cam, how long had it been since the engine last ran? and was the cam dry or did it have oil on it? Most of the time if a lobe gets whiped during the break in it was improper valve lash not lack of oil or break-in lube, unless of course if you let it idle then you deserve a whiped lobe lol
Truthfully if you ran it for at least 5 minutes and get it fixed in a few days with the fact that it fired up immediately I would get it started again and immediately get the idle speed screw on the carb up to rpm and let it finish up. I'm certainly not making light of the importance of the cam break-in procedure but I do believe there has been a certain amount of over hipe put into these things by the cam makers to help cover them.
If you think about it, when you removed the old cam, how long had it been since the engine last ran? and was the cam dry or did it have oil on it? Most of the time if a lobe gets whiped during the break in it was improper valve lash not lack of oil or break-in lube, unless of course if you let it idle then you deserve a whiped lobe lol
Thread Starter
Drifting
Joined: Dec 2004
Posts: 1,714
Likes: 42
From: Austin Texas
Thinking back over my assembly, I believe my error was not putting RTV on both sides of the front and rear rubber oil pan gasket pieces.
The leak is either the bottom of the two piece timing cover OR the front rubber oil pan seal and I know I did not use RTV on the pan seal.
I was so pumped up to be done with this project and drive the car.
Thanks for the kind words.
The leak is either the bottom of the two piece timing cover OR the front rubber oil pan seal and I know I did not use RTV on the pan seal.
I was so pumped up to be done with this project and drive the car.
Thanks for the kind words.
Pro
Joined: Apr 2008
Posts: 596
Likes: 6
From: Irving Texas
Not to highjack this thread but........
What are the physics behind the mysterious cam-break in procedure???
I understand the rpm is to get oil to the cam......but for 20 minutes?
All I know is that my neighbors absolutely hate me when I break-in engines.
Shouldnt the two pieces of steel break-in almost immediately? Its not like we are cutting a metal groove......it's just two pieces of steel rubbing on each other.
I read somewhere that old non roller cam engines were NOT broken-in from the factory.
Am I just getting grumpy in my old age....or can I just break-in an engine for 10 mins?
What are the physics behind the mysterious cam-break in procedure???
I understand the rpm is to get oil to the cam......but for 20 minutes?
All I know is that my neighbors absolutely hate me when I break-in engines.
Shouldnt the two pieces of steel break-in almost immediately? Its not like we are cutting a metal groove......it's just two pieces of steel rubbing on each other.
I read somewhere that old non roller cam engines were NOT broken-in from the factory.
Am I just getting grumpy in my old age....or can I just break-in an engine for 10 mins?
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Not to highjack this thread but........
What are the physics behind the mysterious cam-break in procedure???
Shouldnt the two pieces of steel break-in almost immediately? Its not like we are cutting a metal groove......it's just two pieces of steel rubbing on each other.
I read somewhere that old non roller cam engines were NOT broken-in from the factory.
Am I just getting grumpy in my old age....or can I just break-in an engine for 10 mins?
What are the physics behind the mysterious cam-break in procedure???
Shouldnt the two pieces of steel break-in almost immediately? Its not like we are cutting a metal groove......it's just two pieces of steel rubbing on each other.
I read somewhere that old non roller cam engines were NOT broken-in from the factory.
Am I just getting grumpy in my old age....or can I just break-in an engine for 10 mins?
the break in period at the higher RPM allows the new lifters to spin as they move up and down and wear this pattern into the bottom of the lifter.....if the lifter isnt spinning it is wiping your cam lobe....
Johnt365 you will be fine if its a long time sitting just reprime the engine with oil and start all over again, good luck bob
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Melting Slicks
Joined: May 2009
Posts: 3,079
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2024 C3 of the Year Finalist - Unmodified
From what I have read, there was no carb on the engine and they used natural gas direct to the intake manifold. The engine was started and run without coolant for only a few minutes...just to listen for noises. They were obviously playing the odds. After that, let the public and the dealers solve any problems.
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Just fire it back up and continue the cam break-in.
Happens all the time on start-up.
Oil leaks, water leaks, fuel leaks. My previous cam change had both fuel and water leaks.If you need to shut it down then just shut it off and fix the leak. The important thing is to get the rpm right back up once it fires again. Its the low/slow rpm that kills a flat tappet cam. Low rpm won't make the lifter rotate enough and it will wear a groove pattern that will quickly kill that lifter. But a shut down and start-up with a fast return to higher rpm shouldn't be harmful.
But really now all you can do is restart and hope the cam lives. Only alternative is to replace the cam and if this one fails you will have to do that anyways. So why not try and finish the break in for another 20 min > 2,000 rpm?
Good luck,
cardo0
