Not able to reach zero lash extensions even with lifters pumped up

[Broncobowsher]

Is the cup in the lifter up against the retainer. The little wire clip that keeps the cup from coming out the top.
If it is against the retainer, the pushrod is indeed too short.
If it is not against the retainer, the lifter isn't pumped up. That can happen when the cam is on the lobe and the valve spring pushes the cup down. Worse with new lifters that still have air pockets in them. Soaking doesn't remove the air pockets. A vacuum pot should do it, running the engine will do it.

I can't see enough detail in the pictures if the plunger cup is compressed or against the retainer.

 

[joshua]

Is the cup in the lifter up against the retainer. The little wire clip that keeps the cup from coming out the top.
If it is against the retainer, the pushrod is indeed too short.
If it is not against the retainer, the lifter isn't pumped up. That can happen when the cam is on the lobe and the valve spring pushes the cup down. Worse with new lifters that still have air pockets in them. Soaking doesn't remove the air pockets. A vacuum pot should do it, running the engine will do it.

I can't see enough detail in the pictures if the plunger cup is compressed or against the retainer.

They are used lifters and at the top. Like I said I even swapped lifters around, and the locations that reached zero lash still reached zero lash even with different lifters. And the locations or cylinders(how ever you want to map them) that didn’t reach zero still didn’t reach zero lash even though the lifters I swapped into those locations were able to reach zero lash on different cylinders. I was constantly running a drill to keep oil pressure up. It’s a fresh motor with a fresh pump and holding 60 psi with drill at very low rpm.

What I’m trying to say is, the cylinders reaching zero lash are always reaching zero lash no matter of combo of musical lifters I throw at them. And the cylinders not reaching zero lash are always falling no matter what musical lifter I throw in there. I really hope that makes sense.

 

[joshua]

I overnighted those rods, hopefully be here by Tuesday. I’ll report back what happens with the fit.

 

[73azbronco]

I find it odd you need longer pushrods if head or block was machined. Leads me to think the heads did not come with the block. Oh, stock cast iron heads?

 

[joshua]

I find it odd you need longer pushrods if head or block was machined. Leads me to think the heads did not come with the block. Oh, stock cast iron heads?

It’s very odd I agree. Yes stock cast heads. I checked the stamping on them and it would go with this era mustang engine. I’m kinda wondering if I need a different cam. Does this look like the rocker has really high lift?

 

[Broncobowsher]

My guess at this point, the cam is a regrind. Since material isn't added for what is worn/damaged, the base circle has to be trimmed to get the lobe lift.
That is all I can think of for a reason for needing a longer pushrod on what sounds like a fairly stock engine.

 

[73azbronco]

bingo, thats the answer, cam has been ground under size.

 

[joshua]

bingo, thats the answer, cam has been ground under size.

Yes I figured it is the cam, was said in an earlier post. But it’s an after market cam. I worried that the lift is so high that they made the base circle lower for insulation purposes.

 

[nvrstuk]

I can't see any of your pics besides the small size...

Can you put a dial indicator inside the valley and measure the actual travel of each lifter?? W/O load on the lifters and visually being able to measure against the side of the lifter you could verify if all the exh and all the int lift #'s are the same which might help determine if/why some of the lifters "might" be moving more than others in case ... that's why some of the lifters seem to be moving against the pushrod and others aren't? You can also check it against the actual cam grind numbers

 

[joshua]

I can't see any of your pics besides the small size...

Can you put a dial indicator inside the valley and measure the actual travel of each lifter?? W/O load on the lifters and visually being able to measure against the side of the lifter you could verify if all the exh and all the int lift #'s are the same which might help determine if/why some of the lifters "might" be moving more than others in case ... that's why some of the lifters seem to be moving against the pushrod and others aren't? You can also check it against the actual cam grind numbers

I searched the numbers, they came up with random jargon and ai guesses. But yes I do have a dial indicator.

 

[nvrstuk]

I searched the numbers, they came up with random jargon and ai guesses. But yes I do have a dial indicator.

Least you can check consistency of each lobe btw exh & intakes then.

 

[Broncobowsher]

Yes I figured it is the cam, was said in an earlier post. But it’s an after market cam. I worried that the lift is so high that they made the base circle lower for insulation purposes.

Probably more to do with the core they started with.

 

[joshua]

Least you can check consistency of each lobe btw exh & intakes then.

I’m almost thinking I should just get a different cam

 

[Broncobowsher]

I’m almost thinking I should just get a different cam

If you have no idea what the cam is ground to, it might be a good idea. Not just the pushrod stuff, but how well will it actually run? The regrind might be a performance regrind in a direction you don't want.

 

[DirtDonk]

Expensive guess though.
How much does a roller cam cost these days? Maybe 500 and up?

You may end up going that way anyway, but since you say you have a dial indicator, why not just check the one you have first.

 

[73azbronco]

man I'm not sure with the specs you could search back to find what it is or does best. I mean AI links back to here for answers

 

[m_m70]

I thought I read somewhere that when converting some blocks to roller cams from flat tappet that they needed had a reduced base circle cam???? Not sure, it was some time ago...Your '87 should have came with a stock roller cam though right? not sure if they are even interchangeable....

 

[joshua]

I thought I read somewhere that when converting some blocks to roller cams from flat tappet that they needed had a reduced base circle cam???? Not sure, it was some time ago...Your '87 should have came with a stock roller cam though right? not sure if they are even interchangeable....

Yes, it was definitely made a roller from the factory. It has the raised flanges in the cast where it is tapped for the spider bracket. And the lifter bores are much taller.

 

[nvrstuk]

By measuring the lift of each lobe, you would 100% rule out whether it was potentially a lifter(s) or the cam or both.

Cams aren't cheap & that's half of your purchase... 16 lifters to go with it. Just mentioning it is all. Confidence that you're headed. The right direction is great also...

 

[joshua]

If you have no idea what the cam is ground to, it might be a good idea. Not just the pushrod stuff, but how well will it actually run? The regrind might be a performance regrind in a direction you don't want.

@nvrstuk I tagged you because you must of snuck in a post while I was typing.

I hear that. But I don’t see any evidence of anything else to support performance. Especially running the stock stamped rockers. But ya it was for a mustang so who knows.

I did order the pushrods through scamazon. As I tried to over night a set of rods from JEGS, but apparently they won’t ship it the 17th And Amazon will be here Saturday with free returns if I don’t open them.

I will be measuring with the dial indicator this weekend, because I got a little frustrated with the whole debacle and Saran wrapped the engine to work on other parts of the bronco. And don’t want to cut it back off until I get the new lifters as well.