340 Lifter failure, now what

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Was something else changed to prevent this(wire retainers coming out) from happening again?
 
PRH said:
Was something else changed to prevent this(wire retainers coming out) from happening again?
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I will be changing pushrod length. The ones that were in there had no preload on the lifters. I will be measuring for new pushrods that provide correct .020 to .050 preload.
 
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I would like an opinion on my current 284/484 purple cam.
 
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Generally, performance cams like that from a “cam grinder” would have .0020-ish lobe taper(front to rear).
MP cams typically have closer to .0010-ish lobe taper.
Less taper = less lifter rotation.

The wear pattern on your cam is fairly well centered on the lobe, which is typical when there is less lobe taper.

My suggestion is to very carefully verify that each lifter has some positive rotation every time it goes up/down.
It doesnt need to move much...... but it has to move.
I would also use cam lube on the lifter faces and treat the first start up like you would to break in a new cam.

If any of the lifters don’t turn...... it won’t live.

As far as “wear” goes..... looking at pics on my phone....... it looks okay.
 
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Just hate you have to go through all this. I might be doin the same thing. I need to pull my intake and see whats goin on also.
 
PRH said:
Generally, performance cams like that from a “cam grinder” would have .0020-ish lobe taper(front to rear).
MP cams typically have closer to .0010-ish lobe taper.
Less taper = less lifter rotation.

The wear pattern on your cam is fairly well centered on the lobe, which is typical when there is less lobe taper.

My suggestion is to very carefully verify that each lifter has some positive rotation every time it goes up/down.
It doesnt need to move much...... but it has to move.
I would also use cam lube on the lifter faces and treat the first start up like you would to break in a new cam.

If any of the lifters don’t turn...... it won’t live.

As far as “wear” goes..... looking at pics on my phone....... it looks okay.
Click to expand...

I lubed the sides of the lifters in motor oil and the faces of them with Crower’s ZPaste and acting as if new break in... if I ever get to that point while sorting rockers, shafts, and pushrods. Oh and when installing each lifter I verified that it could easily rotate in the bores and move up and down etc. so as long as the cam rotates them... should be ok.
 
Wvbuzzmaster said:
I lubed the sides of the lifters in motor oil and the faces of them with Crower’s ZPaste and acting as if new break in... if I ever get to that point while sorting rockers, shafts, and pushrods. Oh and when installing each lifter I verified that it could easily rotate in the bores and move up and down etc. so as long as the cam rotates them... should be ok.
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Hmmmmm
Im not big on using used parts in particular flat tappet cams. I have had to many bad experiences in past decades. For the cost of cam and some gaskets I would have replaced it.
Only time and miles will tell.
I wish you the best of luck.
 
512Stroker said:
Hmmmmm
Im not big on using used parts in particular flat tappet cams. I have had to many bad experiences in past decades. For the cost of cam and some gaskets I would have replaced it.
Only time and miles will tell.
I wish you the best of luck.
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I drove the car to where it is sitting so I might not be a fan of potential shortcuts... I am also not wanting to pull the engine. (Yes I know I could pull rad and grill but still have a stock torque converter). I looked at each lifter that came out to make sure it had a decent rotational looking wear pattern and they all did. I was hoping to see the cam looking prettier than it does... but it is what it is...
 
Wvbuzzmaster said:
I drove the car to where it is sitting so I might not be a fan of potential shortcuts... I am also not wanting to pull the engine. (Yes I know I could pull rad and grill but still have a stock torque converter). I looked at each lifter that came out to make sure it had a decent rotational looking wear pattern and they all did. I was hoping to see the cam looking prettier than it does... but it is what it is...
Click to expand...
Maybe I missed it
How many miles on the cam?
 
Wvbuzzmaster said:
I lubed the sides of the lifters in motor oil and the faces of them with Crower’s ZPaste and acting as if new break in... if I ever get to that point while sorting rockers, shafts, and pushrods. Oh and when installing each lifter I verified that it could easily rotate in the bores and move up and down etc. so as long as the cam rotates them... should be ok.
Click to expand...
With the push rods installed, preload set and the intake off rotate the engine to ensure that each lifter is rotating properly. Dont get nuts with the number of crank rotations or you will kung fu your breakin procedure.
I dont think this is going to work.
Best of luck.
 
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What type lifters did you get? Hopefully something more heavy duty with snap ring retainers instead of those ridiculously weak *** wire retainers.
 
Wvbuzzmaster said:
I will be changing pushrod length. The ones that were in there had no preload on the lifters. I will be measuring for new pushrods that provide correct .020 to .050 preload.
Click to expand...

Correct according to whom? That seems like an awfully light preload setting.
 
If the circlips popped out & are the paper clip variety, you probably had lifter pump up. Pushrods collateral damage....
 
Wvbuzzmaster said:
I will be changing pushrod length. The ones that were in there had no preload on the lifters. I will be measuring for new pushrods that provide correct .020 to .050 preload.
Click to expand...
You might peruse the utube vids on "rocker arm geometry". good info on pushrod length needed.
 
Bewy said:
The 'best' FT hyd lifters [ solids also ] in this day & age of cam/lifter failures are factory lifters [ or lifters at least 25 yrs old ] that have been re-faced. We have been re-facing lifters here for decades because of the high cost of new ones.
The problem was never the oil, but the oil companies saw an opportunity....
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None.

Buy some enginetech off ebay @54 bucks and break'em in.
 
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