Tick Tick goes the magnum.

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Slantsix64 said:
yes factor lifters, i installed them with the oil hole facing up.
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Well, all I got is like I originally told you. Hydraulic rollers need a bit of preload. If I remember right, you can depress those plungers close to 1/4" so .080" isn't much in the grand scheme of things. Some cam makers recommend as much as 2 full turns down. All I've ever read, heard, seen and DONE is put more preload on a hydraulic roller than a standard flat tappet.

Are you 100% SURE you're measuring correctly? How are you doing it?
 
RustyRatRod said:
Well, all I got is like I originally told you. Hydraulic rollers need a bit of preload. If I remember right, you can depress those plungers close to 1/4" so .080" isn't much in the grand scheme of things. Some cam makers recommend as much as 2 full turns down. All I've ever read, heard, seen and DONE is put more preload on a hydraulic roller than a standard flat tappet.

Are you 100% SURE you're measuring correctly? How are you doing it?
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yes i believe so i even triple checked I verified TDC at the number 1 cylinder added my push rod checker until there was no slack i got 6.905 i even double checked that by using the stock magnum pushrod which is 6.900 and there was a little play, so i knew my reading of 6.905 was correct. then added 0.030 for preload total of 6.935.
 
Slantsix64 said:
yes i believe so i even triple checked I verified TDC at the number 1 cylinder added my push rod checker until there was no slack i got 6.905 i even double checked that by using the stock magnum pushrod which is 6.900 and there was a little play, so i knew my reading of 6.905 was correct. then added 0.030 for preload total of 6.935.
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Depending on thread pitch, .030 is around like 1/4 turn down. I know yours is non adjustable, I'm simply giving that as a point of reference. That's a very light touch with preload. I believe it needs more. I believe I would listen to Hughes.
 
Did you replace the cracked rocker arm mentioned in post 14? Are there any other damaged rocker arms?
Use your adjustable checking pushrod and check every single pushrod length, all 16 of them. Maybe your numbers are good for the cylinder you are checking but far enough different for another cylinder that different lengths will be required. This is possible.
Assume nothing and check everything at this point.
 
Bobzilla said:
Did you replace the cracked rocker arm mentioned in post 14? Are there any other damaged rocker arms?
Use your adjustable checking pushrod and check every single pushrod length, all 16 of them. Maybe your numbers are good for the cylinder you are checking but far enough different for another cylinder that different lengths will be required. This is possible.
Assume nothing and check everything at this point.
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yes i did check all the rockers for cracks, i only check the exhaust and intake push rods on the number 1 cylinder will check the others. I did notice even though it is chattering with the 6.935 pushrods its about 40 percent less chatter than running the longer 6.965 push rods. So i believe i am getting close. i will upload a video shortly
 
I just noticed your location is Twilight Zone. Lol.
A video never sounds right. Hard to tell what is normal and excessive that way.

Less chatter from shorter pushrods does not make sense unless the noise is all from the valves hanging open popping through the intake, running into retainer to guide clearance issues, or maxing out and binding the rocker arm travel. You may need to have someone get a fresh set of eyes on it, and not just local joker.
 
Bobzilla said:
I just noticed your location is Twilight Zone. Lol.
A video never sounds right. Hard to tell what is normal and excessive that way.

Less chatter from shorter pushrods does not make sense unless the noise is all from the valves hanging open popping through the intake, running into retainer to guide clearance issues, or maxing out and binding the rocker arm travel. You may need to have someone get a fresh set of eyes on it, and not just local joker.
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hahah yup the twlight zone AKA Los Angeles i seen on the magnum swap form the wrote this about lift with factory heads, i did use the hughes spring and retainer kit

There is a persistent rumor that the Magnum engine will not tolerate camshafts with higher than .520 lift due to retainer/lock to valve guide clearance issues. This is not true. While max lift is related to cam duration and other factors, we are using a .550+ lift cam in our shop car, did not need to flycut the pistons, and have more than the minimum clearance.
 
Heres two videos its less noisey than before with the longer push rods, honestly most of the sounds is coming out the carb lol


 
Hard to tell from the videos but I think that noise is under the carb, not coming from the carb.
Hopefully measuring every pushrod location individually will find a problem somewhere.
 
Bobzilla said:
Hard to tell from the videos but I think that noise is under the carb, not coming from the carb.
Hopefully measuring every pushrod location individually will find a problem somewhere.
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so, i was measuring all the pushrods one rocker i noticed has alot of side to side play removed it and saw the push rod was bent. greaaat sounds like i have alot of issues to figure out, what would cause a push rod to get bent?
 
Slantsix64 said:
so, i was measuring all the pushrods one rocker i noticed has alot of side to side play removed it and saw the push rod was bent. greaaat sounds like i have alot of issues to figure out, what would cause a push rod to get bent?
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Piston to valve contact. Not much else, really.
 
RustyRatRod said:
Piston to valve contact. Not much else, really.
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Great well this is my brothers motor and he does not do any research on parts hes putting together no measuring done. Think he went a little crazy on the lift this time around.
 
Time for more details about the engine.
Is it a stock lower end, or is it aftermarket pistons? What heads are on it and were they used, rebuilt used, or some kind of new replacements?
 
Bobzilla said:
Time for more details about the engine.
Is it a stock lower end, or is it aftermarket pistons? What heads are on it and were they used, rebuilt used, or some kind of new replacements?
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Bobzilla, Motor has stock pistons engine had 78,000 on it, stock heads upgraded with hughes valve springs. im going to check all the exhaust pushrods because there at .533 lift and compare them to the intake which is .507 see which are bent
 
Found only two push rods that were bent on the driver side cylinder head exhaust side, so found my problem will a stock magnum handle .533 lift nope not in my case, probably going to pull the camshaft and regrind the original one it came with under .500 in the .480-.490 range lift thanks guys on all the help i guess it all makes sense in the end.
 
What head gaskets are you running? If they're thin maybe you can put a much thicker set on and keep your cam. You'd better pull those heads anyway and make sure the valves weren't bent.
 
Check retainer to guide clearance too. That's a lot of lift for stock heads with uncut guides. If the retainers are hitting the guides, that could be both your noise and problem with bent pushrods. When the retainers hit the guides, it becomes solid and "something" has to give, which is usually the pushrods.
 
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