Re: 440 Cam is tight
[Re: CYACOP]
#499783
10/17/09 07:26 PM
10/17/09 07:26 PM
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Joined: Sep 2003
Posts: 815
PNW
Danan
super stock
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super stock
Joined: Sep 2003
Posts: 815
PNW
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OK, I'll take a stab at this..
First off, is it tight with a little oil on it or is it tight with thick assembly lube? I've tried several methods of freeing up cams, and I'm not enthused about any of them. I heard one good way to do it is to grind slots in the journals of an old cam and then dress the edges so they are clean and flush with the bearing circumference. You then insert this 'tool' and slowly turn it until it cuts/scrapes the high spots down. This seems like a good idea but I always forget about making the 'tools' and always pitch my old cams. Otherwise, I've scraped bearings and even sanded them when I was trying to just knock an edge down. I suppose you could try to find an old bearing scraper, but I've never seen one for sale, so I don't know how likely that would be.
That said, providing you aren't running a lot of spring pressure or high rpm, you should probably be okay if one journal has a bit of a tight spot. The cam doesn't take a lot of abuse in a street engine, and I got 100k plus miles out of a truck engine with a pretty tight cam. I normally don't suggest allowing components to 'self-clearance', but it worked in this instance. I've found that small blocks are WAY worse than big blocks when it comes to misalignment in the cam bores. Just one of many reasons to build a big block! Keep us posted..
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Re: 440 Cam is tight
[Re: Danan]
#499787
10/17/09 09:22 PM
10/17/09 09:22 PM
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Joined: Feb 2005
Posts: 3,958
SW Fla.
CYACOP
OP
master
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OP
master
Joined: Feb 2005
Posts: 3,958
SW Fla.
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Quote:
OK, I'll take a stab at this..
First off, is it tight with a little oil on it or is it tight with thick assembly lube? I've tried several methods of freeing up cams, and I'm not enthused about any of them. I heard one good way to do it is to grind slots in the journals of an old cam and then dress the edges so they are clean and flush with the bearing circumference. You then insert this 'tool' and slowly turn it until it cuts/scrapes the high spots down. This seems like a good idea but I always forget about making the 'tools' and always pitch my old cams. Otherwise, I've scraped bearings and even sanded them when I was trying to just knock an edge down. I suppose you could try to find an old bearing scraper, but I've never seen one for sale, so I don't know how likely that would be.
That said, providing you aren't running a lot of spring pressure or high rpm, you should probably be okay if one journal has a bit of a tight spot. The cam doesn't take a lot of abuse in a street engine, and I got 100k plus miles out of a truck engine with a pretty tight cam. I normally don't suggest allowing components to 'self-clearance', but it worked in this instance. I've found that small blocks are WAY worse than big blocks when it comes to misalignment in the cam bores. Just one of many reasons to build a big block! Keep us posted..
Im doing a slightly more than a stock build on a fresh lower end including pistons. I did have the shop install them and cannot tell extactly which journal is causing the problem or weather or not its an alighnment of the bore. Whats the best way to to cut the slots in the old cam? With a hacksaw? Yea Im thinking I dont want to spin one of the bearings, they are lubed with just motor oil.
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Re: 440 Cam is tight
[Re: Neil]
#499788
10/17/09 09:24 PM
10/17/09 09:24 PM
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Joined: Feb 2005
Posts: 3,958
SW Fla.
CYACOP
OP
master
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OP
master
Joined: Feb 2005
Posts: 3,958
SW Fla.
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Quote:
Check your cam bearings for any nicks or burrs. I paid the shop to install my last set and learned my lesson. Just one more part I will be doing myself from now on.
Neil
The bearings all look and feel fine, I think I would have felt something when I lubed them with my finger all the way around.
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Re: 440 Cam is tight
[Re: 440newport]
#499790
10/18/09 12:05 AM
10/18/09 12:05 AM
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Joined: May 2007
Posts: 1,443
Maryland
Dads426
pro stock
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pro stock
Joined: May 2007
Posts: 1,443
Maryland
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On our 340 the machine shop mushroomed the front of the rear cam bearing (from hitting it in). Scraped the edge of the bearing and the cam turned fine. There were noticable shiney spots on the front of the bearing when the cam was test fitted and wouldn't turn. Look carefully at the entire bearing.
2012 422 Allstars NSS Champion
2013 422 Allstars NSS Champion
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Re: 440 Cam is tight
[Re: Dads426]
#499791
10/18/09 08:24 AM
10/18/09 08:24 AM
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Joined: Feb 2005
Posts: 3,958
SW Fla.
CYACOP
OP
master
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OP
master
Joined: Feb 2005
Posts: 3,958
SW Fla.
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Update: Took my 4 1/2" grinder to the old cam and made the tool. Duct taped the lubes so I wouldnt cause more damage with nicks and reamed the bore. Took very little. Cleaned out the holes and checked new cam and moves like it should. Thanks for the help, I appreciate your feedback. 
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Re: 440 Cam is tight
[Re: CYACOP]
#499792
10/18/09 12:17 PM
10/18/09 12:17 PM
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Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
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Glad you got it. I used to use a fine brake hone but after a prior thread on this touting the ease & advantages of slotting an old cam & how it worked for you on my next one that's what I am going to do.
live every 24 hour block of time like it's your last day on earth
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