Fuel delivery question regarding fuel pump

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How does one measure the proper pushrod length required to take up the gap? What is the proper measurement of gap from pushrod to rocker?

 
They make an adjustable pushrod for measuring length. Say your heads were milled .030" a pushrod .030" longer would be required to take up the slack. A stud mount rocker conversion with guide plates would have been ideal for drivetrain stability and adjustabilty. I'm suprised for the money you paid they didn't do that conversion. I would make sure you don't have any loose rocker arms first before you do anything else.

 
They make an adjustable pushrod for measuring length. Say your heads were milled .030" a pushrod .030" longer would be required to take up the slack. A stud mount rocker conversion with guide plates would have been ideal for drivetrain stability and adjustabilty. I'm suprised for the money you paid they didn't do that conversion. I would make sure you don't have any loose rocker arms first before you do anything else.
Would the pushrod need to be longer or shorter? Seems to me that if you take material off the head the push rods would need to be shorter. Also it was mentioned that the cam was changed, if the base diameter of the lobes is different than stock then that would affect pushrod length too.

Lastly when you have an engine built you don't really know what you are getting. Today most shops are interested in volume vice quality and they tend to cut corners. I learned that the hard way, wrong bearings and pushrods lengths were installed on my motor.

 
They make an adjustable pushrod for measuring length. Say your heads were milled .030" a pushrod .030" longer would be required to take up the slack. A stud mount rocker conversion with guide plates would have been ideal for drivetrain stability and adjustabilty. I'm suprised for the money you paid they didn't do that conversion. I would make sure you don't have any loose rocker arms first before you do anything else.
Would the pushrod need to be longer or shorter? Seems to me that if you take material off the head the push rods would need to be shorter. Also it was mentioned that the cam was changed, if the base diameter of the lobes is different than stock then that would affect pushrod length too.

Lastly when you have an engine built you don't really know what you are getting. Today most shops are interested in volume vice quality and they tend to cut corners. I learned that the hard way, wrong bearings and pushrods lengths were installed on my motor.

I'm no expert on pushrod lengths by any means, but something is definately wrong there or you have some loose rocker arms. Then again maybe I'm just ignorant lol.

 
They make an adjustable pushrod for measuring length. Say your heads were milled .030" a pushrod .030" longer would be required to take up the slack. A stud mount rocker conversion with guide plates would have been ideal for drivetrain stability and adjustabilty. I'm suprised for the money you paid they didn't do that conversion. I would make sure you don't have any loose rocker arms first before you do anything else.
Would the pushrod need to be longer or shorter? Seems to me that if you take material off the head the push rods would need to be shorter. Also it was mentioned that the cam was changed, if the base diameter of the lobes is different than stock then that would affect pushrod length too.

Lastly when you have an engine built you don't really know what you are getting. Today most shops are interested in volume vice quality and they tend to cut corners. I learned that the hard way, wrong bearings and pushrods lengths were installed on my motor.

I'm no expert on pushrod lengths by any means, but something is definately wrong there or you have some loose rocker arms. Then again maybe I'm just ignorant lol.
I am no expert either that's why I ask these questions. I try to learn everything that I can on this forum. I remember a 289 that was in a new car we got and the valve train was really noisy. Turned out that they just need to set the proper lash and everything quieted down. I am thinking that this is probably the problem here.

 
I would think if heads were milled the pushrods would end up too long, how would that create extra noise? Am I think about this wrong?

 
I would think if heads were milled the pushrods would end up too long, how would that create extra noise? Am I think about this wrong?
Nope, not wrong.

I think Chuck knows what's going on here...

 
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While they're at it, have the shop look at the seal for the water outlet/thermostat housing. Looks as if someone sealed it with RTV instead of putting a gasket.

FYI - if the bog on acceleration remains after these yokels get your valvetrain done right (they certainly failed the first time, as that video proves), check the color/size of the accelerator pump cam on your Holley's throttle linkage:

20-12.jpg


I was getting a bog on acceleration with the '78 Mark V when I first put a Holley 4160 on its 400. I think it had the pink cam on the carb when I started, and I had to go up a few sizes. The problem is gone at all but the most aggressive requests for WOT, which have a bit of a bog. One size up or a slightly different cam pattern would probably do the trick.

-Kurt

 
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Tougher to do right with OEM non-adjustable "shoe" rocker. You will need a appropriate dial indicator set up, and know what the proper preload for the lifters you are using is. It varies somewhat from vendor to vendor. Basically with the lifter on the base circle (lowest place) and the pushrod in place, at zero lash, the dial indicator on the pushrod side of the rocker at the oil hole and parallel to the pushrod, tighten the bolt to spec. while looking to see how much the dial indicator moves. Compare that to the pre-load value desired. If it is significantly out of spec., too deep/too long, do the math to determine how much too long. Check one intake and one exhaust. If it is about .015 to about .050 too long you may be able to use rectangular shims between the bottom of the fulcrum and the pedestal on the head. The option is a shorter pushrod. If the pushrod is too short (I don't see that in your case, unless they were changed?), a longer pushrod is the only realistic solution. The common pushrods come in .050 length increments($). The not so common ones can be anything you want ($$).

Here is one alternative process from Comp Cams.

"Setting Hydraulic Lifter Pre-load (Non-Adjustable Valve Train)

COMP Cams® recommends using an adjustable pushrod to check the pre-load . Typically, only one cylinder needs to be checked in this process . After applying lube, install the adjustable pushrods and assemble the valve train . Using the same procedure mentioned earlier, adjust the intake and exhaust valves to zero lash by changing the length of the adjustable pushrod for precise fitment. Order a pushrod that is .020"- .070" longer than the pushrod length at zero lash to ensure the proper pre-load."

Ask the "mechanic" how much the heads were milled (have they been milled before?) what the installed spring heights are, and what procedure was used to break-in the cam and lifters. Then tell him the symptoms and ask how he proposes to resolve the problem.

Remote starter switch to turn the engine using the starter (key off). http://www.autozone.com/autozone/accessories/Tools-Garage-and-Equipment/Remote-Starter-Switch/_/N-25eo

The "mechanic" should be doing this. Pull the valve covers, key off, rotate the engine to see if some of the rockers never have the slack taken up. If so, I doubt it is good news. Next step is pull the intake to inspect the lifters and cam lobe surfaces

One example of break-in procedure. http://www.cranecams.com/uploads/breakin/548e.pdf

I hope it all works out. Chuck

 
If the heads were milled, wouldn't the pushrods be too long. That being the case, why would I have so much clatter? They did replace a few bent pushrods but I have no idea how they decided on length. I will call in the morning and ask.

Is there an option to buy a rocker arm that can be adjusted to set gaps properly? I will take the car elsewhere to do this. I am getting a bit frustrated with the whole thing to be perfectly honest because I turned in my lease and I don't have time to leave my car in the shop. I should not have had to adjust rear and front float but I did. This is really starting to piss me off. Went and asked my friend about his newly rebuilt Cleveland and he sold the car a week ago with engine for 1600, I was bumbed because it was going to be mine.

 
Is his the correct method. I like videos because it is a lot easier for me to follow. In other words, I am not a by the book kind of guy. I have successfully torn my sporty apart a gazillion times and this should be easy. https://www.youtube.com/watch?v=piifbQtCzno

 
Yes

IF YOU HAVE ADJUSTABLE ROCKER ARMS

From the factory a 351c has bolts that hold the rocker down without the ability to adjust them like in the video.

The adjustment is made with a different length pushrod.

c9zx gave you a link to the work-around conversion to convert a 351c to adjustable type rockers like the video.

you need to look to see what your rocker arm style is.

Regards

Paul

 
I am planning to buy the bits and pieces needed to put on adjustable rockers. Was hoping to find a kit with all the parts. Can't find one at Summit. IS there a standard push rod? 5/16 or 3/8 for a 72 Cleveland or take out and measure?

 
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What ratio rocker arm is required for a 351?

 
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351C and 429/460 use the same rocker and are 1.72 ratio.

Ralph, was the valvetrain quiet when you brought it home, and got progressively louder with use?

 
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