Push rods are loose

keel · Jul 24, 2023

I just installed a TFS1 camshaft and a set of 3 bar GT40 heads on an otherwise stock block. The lifters were also replaced but are an OEM replacement from Ford. I am trying to reuse the stock push rods and rocker arms, but when I torqued them down, the rocker arms were very loose and I am able to jiggle the push rods up and down slightly. This would indicate to me that the cam might have a smaller base circle than the stock one but as far as I know, the TFS1 uses the same base circle as a stock cam. I'm wondering if this is normal with fresh lifters that have never been pumped up, or if I need longer push rods. Has anyone else running the same combo also had this issue?

bird_dog0347 · Jul 24, 2023

Any time you replace the cam and aren't using stock heads and cam you need to measure the pushrod length and get the correct ones.

keel · Jul 24, 2023

Where is a good place I could find push rods that are a little longer or custom length?

Kid wita 5oh · Jul 25, 2023

You need to get an adjustable push rod and find out what length you need. Then just order that length from summit or jegs or where ever

limp · Jul 25, 2023

keel said:
Where is a good place I could find push rods that are a little longer or custom length?

Smith Bros in Redmond OR....
I was able to make these work on my car

bird_dog0347 · Jul 25, 2023

keel said:
Where is a good place I could find push rods that are a little longer or custom length?

Agreed, you need the adjustable push rod and the modified "solid" lifter to test it with, then measure and order pushrods in that length. I think I still have the tools here from when I did my HCI install years ago and doubt I'll need them again since my new engine will be the 4.6 4V so if you want I could sell them to you.

Mustang5L5 · Jul 25, 2023

I concur. You will need to get an adjustable pushrod and make a solid lifter and check. Stock pushrods may work, but they may not be ideal.

I think this is the correct range you will need. Might be able to get off Amazon

https://www.jegs.com/i/COMP-Cams/249/7701-1/10002/-1

You can also get the priming tool that fits in the dist to spin the pump and prime the lifters, but the initial check with the adjustable pushrod needs to be made with a solid lifter (use one of the originals and flip the internal cup to make it solid.

keel · Jul 25, 2023

Do I need to add length to a zero lash measurement for hydraulic lifter preload?

@bird_dog0347 thanks for the offer but I already ordered the solid lifter and adjustable push rod kit from LMR .

limp · Jul 25, 2023

keel said:
Do I need to add length to a zero lash measurement for hydraulic lifter preload?

@bird_dog0347 thanks for the offer but I already ordered the solid lifter and adjustable push rod kit from LMR .

I gave up attempting to gut a hydraulic, and did the same thing....

Dan02gt · Jul 26, 2023

keel said:
Do I need to add length to a zero lash measurement for hydraulic lifter preload?

@bird_dog0347 thanks for the offer but I already ordered the solid lifter and adjustable push rod kit from LMR .

Yes you do if you don't have adjustable rocker arms, else the lifter will have to be at the edge of it's travel and you'll have a noisy valve train.

According to some instructions I found from Ford Racing the stock lifters have .140" of possible travel. It's been years since I setup my valve train but I think I ensured that each lifter was compressed around .050". My valve train is almost as quite as a stock engine.

I would suggest measuring with the solid lifter and then measure with a non-pumped up hydraulic lifter to determine what needed to add some preload.

keel · Jul 31, 2023

I got my adjustable push rod and measured the length to reach zero lash. The stock length push rods measured out to 6.250" and the adjustable rod measured out to 6.270" at zero lash. If I'm shooting for an extra 0.050" for preload, that brings me to ~6.320". However, push rods aren't very readily available in this length. I would like to step up to either a 6.300" or a 6.350" push rod because those sizes would be easy to get.
I read on a similar thread that anywhere between 0.030" and 0.080" of length past zero lash is acceptable, but this means that choosing the 6.300" puts me right at the bottom end of that range and choosing the 6.350" puts me right at the top end. My question is which push rod length would be best for my application between the two options I have outlined.

limp · Jul 31, 2023

Perhaps I am missing something here..........
The goal here is after reaching zero lash, you want 1/4-1 full turn on your rocker bolt to reach torque spec..
My engine goal was 1/2 to 3/4 to reach the torque specs...
Thats what you need for the correct length of your pushrods....
I would want to double check my torque number, but I believe it was 22 FtLbs......

keel · Jul 31, 2023

Okay I will try that approach then. Should be able to set the adjustable rod to 6.300" or 6.350" and then test to see how many turns to reach torque spec from zero lash.

limp · Jul 31, 2023

keel said:
Okay I will try that approach then. Should be able to set the adjustable rod to 6.300" or 6.350" and then test to see how many turns to reach torque spec from zero lash.

If you have established you zero lash number with your solid lifter, now use a hydraulic for your " turn for final torque number......
Look for good geometry on your rocker/valve/pushrod, then check your rocker arm to valve contact with some grease.....
Adjust your intake as the exhaust starts to open.....
Adjust your exhaust as the intake starts to close......
When working towards zero lash, the claim is todays modern synthetic oils make the " twist " method ( rolling the pushrod till snug) not as accurate as the up and down method until no movement.....
Take your time and don't get in a hurry....

keel · Jul 31, 2023

If my contact area needs adjustment how do I do that with the stock rocker arm set up?

limp · Aug 1, 2023

keel said:
If my contact area needs adjustment how do I do that with the stock rocker arm set up?

Personally, if its not way bad, for a simple street machine no biggie... I would guess that MOST of us do not have optimal valve contact...
A high lift, high spring rate, racing engine..... Probably a bit more of a concern....
The perfect contact mark is LESS important then good rocker geometry
" The pushrod length sets the preload, shims set the valve contact"
Do you have any pics?

https://www.summitracing.com/parts/fms-m-6529-b302/make/ford

keel · Aug 1, 2023

No pics yet, I will check valve contact when my push rods arrive instead of using the adjustable one to make sure I get an accurate reading. I set the adjustable push rod to 6.300" and it took a little over 3/4 of a turn to reach torque spec after achieving zero lash for all the rocker arms, so that is the length I settled on.

slow84lx · Aug 2, 2023

bird_dog0347 said:
I think I still have the tools here from when I did my HCI install years ago and doubt I'll need them again since my new engine will be the 4.6 4V so if you want I could sell them to you.

Nick, if you come across these in the near future and there is not already a taker send me a message or text.

limp · Aug 2, 2023

What wall thickness are your new pushrods? 060 is stock..

keel · Aug 2, 2023

I ordered the trick flow push rods on Summit which have a 0.080" wall thickness.

Push rods are loose

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still married haven't seen testicles in years

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I'm definitely not in the original hole

wrap a little cheese around it and its a done

still married haven't seen testicles in years

That is…until I whipped out my Bissell

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wrap a little cheese around it and its a done

mazing how much gas smell came from that tiny hole

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wrap a little cheese around it and its a done

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wrap a little cheese around it and its a done

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wrap a little cheese around it and its a done

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clean it good before insertion

wrap a little cheese around it and its a done

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