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Discussion Starter #1
Ok, first, sorry for starting a thread for every little problem I have with my truck...but, they're really kinda big problems (like bent pushrods)...and, seperate issues, so for people maybe searching for answers later, it'll be easier to find.

OK, well...I've got a 79 with a 400 that I just put a cam in. During the break in period, I lost oil pressure due to several lifters that jumped out of their bores due to severly bent pushrods.


My question is simply...do you have to go with shorter pushrods (or likewise, shims under the rocker arms) in order not to bend pushrods with a bigger cam? The cam I went with is just under .500 lift, and I changed springs with it anyway...and lifters. Some of the lifters had stuck plungers, which I think is part of the reason I bent pushrods...plus, I tightened the rockers down 3/4 of a turn...which is a little further than recomended...but I've seen recomendations that high before. I'm wondering if it was because the pushrods were too long (factory pushrods)...or, soley because of the stuck plungers, or tightening the rocker arms down just a hair too far, or a combination of everything. I would think that if it was a problem with the pushrods being too long, they all would have bent...but, only like 6 or 7 did, but they bent bad. I've got a new set of lifters coming from summit under warrenty, along with a pushrod length checker. Any and all input is welcome as always...thanks for the help. Jared
 

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If they were comp cams lifters, thats part of your problem. I've had all kinds of problems with their lifters and many others also have. I like there cams, but never again with their lifters.........
 

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A lot of comp cams parts are junk..... making parts over seas and what not has really affected their quality.... here not to long ago, buying a set of valve springs from them was a crap shoot.....
 

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Did you change the spring retainers?

You can't keep the rotating retainers that IIRC come on the exhaust springs from factory.;)
x10.

Other comments: 3/4 turn preload is still 'OK'..so I doubt that is your problem.

Lifters can 'appear' frozen simply due to being fully pumped up and not relieving..that you cannot push some by hand does not mean for certain they are 'frozen' or stuck.

Factory pushrods are not that great and 'stock' aftermarket replacement pushrods are junk. I use Cranes.

=I'm betting on the wrong spring/retainer setup as the cause. Were all of the bent pushrods on exhaust valves?
 

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x10.

=I'm betting on the wrong spring/retainer setup as the cause. Were all of the bent pushrods on exhaust valves?
Is this only for other than stock springs and only on M-blocks?
 

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I've got a Comp cam with .514 lift intake and exhaust, and I haven't bent any pushrods in the motor. Been driving it for about 600-700 miles since I put the cam in.

I'm with BMC69 in thinking that it's probably a spring/retainer issue.
 

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Is this only for other than stock springs and only on M-blocks?

Ya know Ox..I've seen the rotator retainers on some 302s nd 351Ws..most 351m and 400 truck engines (and some others too, like Lincolns). But I don't recall ever seeing any in an FE (FTs yes..but not FEs) and I don't recall ever running acroos any in a 460 either..and certainly not in a 429.

In my experience over the years, the 351m and 400 are the least forgiving of all Ford engines when it comes to using stock valve springs with aftermarket cams. Remember..the stock 351m/400 cams have a weenie .425 lift on average.
 

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Ya know Ox..I've seen the rotator retainers on some 302s nd 351Ws..most 351m and 400 truck engines (and some others too, like Lincolns). But I don't recall ever seeing any in an FE (FTs yes..but not FEs) and I don't recall ever running acroos any in a 460 either..and certainly not in a 429.

In my experience over the years, the 351m and 400 are the least forgiving of all Ford engines when it comes to using stock valve springs with aftermarket cams. Remember..the stock 351m/400 cams have a weenie .425 lift on average.

Just curious cause I did not do anything like that when I did the 460, but my memory was shot when I 8. Thank god for the net, I get to look up stuff before I sound stupid.

I would have done springs if the motor saw more than 50 hours per year running time tops.
 

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Discussion Starter #12
Well, the springs I went with are factory replacement springs, on the original retainers and locks. The motor probably won't see 5000 rpm, so going with a higher pressure spring for 5x the cost seemed a little much. There's no bind in the springs, intake or exhaust. They all tightened up fine...and, yeah, I don't think that 3/4 of a turn would cause that either. The bent pushrods were a mix of intake and exhaust...and, again, I think that if it were a pushrod problem, all of them would have bent with the first cranking of the engine. I too have heard bad things about comp lifters...but I've already got a new set coming, so I'll give them one more shot.

As far as trying to compress the lifter plunger, I was using a vice and a small socket in the center...and if that won't do it, then I would say it's stuck.

I'm at the piont now where I don't really care...I'll replace springs, retainers, pushrods, and rocker arms if I have to. I really, really don't want to have to do all that, and sink that much more money into it, but I will.
 

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Well, the springs I went with are factory replacement springs, on the original retainers and locks. The motor probably won't see 5000 rpm, so going with a higher pressure spring for 5x the cost seemed a little much. There's no bind in the springs, intake or exhaust. They all tightened up fine...and, yeah, I don't think that 3/4 of a turn would cause that either. The bent pushrods were a mix of intake and exhaust...and, again, I think that if it were a pushrod problem, all of them would have bent with the first cranking of the engine. I too have heard bad things about comp lifters...but I've already got a new set coming, so I'll give them one more shot.

As far as trying to compress the lifter plunger, I was using a vice and a small socket in the center...and if that won't do it, then I would say it's stuck.

I'm at the piont now where I don't really care...I'll replace springs, retainers, pushrods, and rocker arms if I have to. I really, really don't want to have to do all that, and sink that much more money into it, but I will.
a set of Comp Cams #972 springs costs 68 bucks. They have less load at .490 lift than the stock springs at same lift ..and..hellooo..won't bind at that lift. Go with all same stock intake retainers on all 16 and use the comp springs and yr golden.
 

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Ok, please don't be offended but what process did you use when doing the cold adjustment of the valve preload? Is it something you have done before?

Just making sure it was done by rotating the motor through properly and adjusting the valve train in the proper order with each lifter on the "heal" of the cam when that rocker preload was set?

The only way 7-8 push rods will bend is something going into a real bad bind...I know, stating the obvious
 

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Discussion Starter #19
Cam is set up right, and yes I set them up by rotating the motor over, and doing the appropriate rocker arms at the right time. What I'm not sure I did right, is tighten the bolt to the proper spec. This is honestly the first time I've done this myself, but, I've read a lot on it, and feel comfortable doing it...or, thought I did, lol. Everyone has to have their first time getting into it, and I have done a lot of other things on a motor, but, specifically, this is my first time setting up rocker arms, and lifters. The whole timing chain, and even the actual cam install, I'm good with, along with the oil pump, water pump, all that crap is easy...it's just this rocker arm business that's got me at a standstill. I'm hearing different things...I've got a manuel, but didn't really use it (I know, I know...) but that was only because I heard so much of the same thing from everywhere, that I felt good wth it. Now, I hear otherwise...

Anyway, thanks for the input, and I think I'm gonna get the new lifters, and a new set of pushrods, perhaps factory length, and then soak the lifters for about 15 minutes, then put it all together, and tighten the rocker arm bolt to 25 lb/ft...none of this half a turn crap.

As for the two threads...I just kinda figured since the other started about oil pressure, and high volume pumps, and this was pretty much a seperate issue, that it should merit a seperate thread.
 
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