Engine Engine rebuild suggestions

#261
Alex;s what? speed shop?
Lunati is one of the better manufacturers IMO
Well worth the cost
Hobbies are expensive
You get a new fuel sender for your 83 on order yet?
I used to give nice DVOMs away (couple of years ago I would have sent you one)
I had a friend at Autoliv that cleaned out their old buildings and they had way too many DVOMs hanging around
Same as their electrician, told me their heat shrink tubing had a shelf life and he threw a few hundred bucks worth of it in the dumpster
Course I took all that too
 

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#265
limp said:
When I did mine I purchased 1 new solid lifter ( per the instructions i read) to take the measurements with the Adjustable pushrod tool to measure. I had better luck using my old pushrods to get a more precise measure than the pushrod tool, but my pushrods were really close to stock length.
Yes, I read about taking an old hydraulic lifter apart and making it solid for the measurement, but I was " unsuccessful in this endeavor.... LOL
6.248 if I recall was stock length and I used 6.250......
The claim is that you can perfect your valve/pushrod contact with a combination of pushrod length and shims... My valve contact is really close but not perfect, but my rocker/valve geometry is just right which is more important in my opinion....
DSCF0832.JPG
Click to expand...

So for my situation-- new lifters, new cam, new heads (heads are new to me- valves shimmed to equal height) using the original stock pushrods, is it normal that one would be snug and the other rocker arm would be loose? Is it normal to only shim some rocker arms and not all? What would cause the difference?
 
#268
Here is what I did...
The specs are 1/4-1 turn to 22 ftpds after zero lash...
I dont like the twist the pushrod method, I prefer to move the pushrod up and down very very slightly with very little pressure... All your trying to do is have no movement or very little... Sometimes the twist method allows the lifter to compress a bit AND you can get to zero lash and still be able to twist the pushrod.. At least this has been MY experience....
I do each piston one at a time, do not jump around... Do both of the valves at one piston before moving on..

rotate your engine by hand with the spark plugs out...
Adjust the intake as the exhaust starts to open
Adjust the exhaust as the intake starts to close...

Do not be in a hurry, take your time... I did mine at least 3 times.. At the end I felt I was getting a pretty good feel on what was correct....

Don't think they will be all 1/4 turn or all 1 turn, these or between these is spec so thats OK.....

My understanding is the rocker shims are more for getting the contact point correct on the valve, but then you have to play more with pushrod length.
If a shim will help you get to torque specs if one is out, by all means use one....or two.....

Simple basics here, lets not try to make it hard.. Were not building 6000 hp drag cars......
 
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#269
That is kind of my point. On number one cylinder, where I'm testing this, I can get to 0 lash on one valve, but not on the other. That's why I think I need longer pushrods, but just wanted to know if it's normal that on the same cylinder, one rocker gets to 0 lash and the other doesn't.

As a reminder-- upgraded to TFS Stage 1 Cam, GT40P heads. New head gaskets from Felt Pro. Stock stamped rockers.
 
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#270
JulianR said:
but just wanted to know if it's normal that on the same cylinder, one rocker gets to 0 lash and the other doesn't.

As a reminder-- upgraded to TFS Stage 1 Cam, GT40P heads. New head gaskets from Felt Pro. Stock stamped rockers.
Click to expand...
Same exact setup I built....
I did NOT say that was normal... get 0 lash then torque down with the specs to see where you are..
Did you at least set one of your pairs of valves using the system in my post??
My guess is you are not at 0 lash correctly...
 
#271
Have not had time to try your method, but had 5 minutes over lunch and went and looked at the engine again. It looks like I was wrong and I do have pushrod play at BOTH exhaust and intake valves. So, I need longer pushrods.

Now the next issue is-- everyone online seems to sell a length checker tool. But I don't see any places that list 5/16" valves of incremental length that I can order. TFS is the only one I found that has that-- but they're on back order expected in June :)

So, my plan is, I have a pretty good up/down play in my pushrods now. Autozone sells my pushrods that are .150 longer than stock. They are Melling MPR-376 pushrods. They seem to fit many different makes as OEM. But they're 5/16" and same end style as my OEM but are 6.390" length. $5 each. I'm going to buy a couple and put them in. If at 0 lash, when I torque them down I'm still within the 3/4 ratchet turn-- I think I'll call it good. Thoughts?
 
#273
Well, just for an update, still haven't found time to measure the new pushrods I got, however, I was able to snag a GT40 upper/lower intake for $50. Will need to clean it up and such, but pretty happy. I do believe it's from an earlier explorer, not later, but it does have EGR and fuel injectors.
 
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#274
Morning, made some time last night to work in the garage. Here's what I did.

All my new hydraulic lifters are oil free.
Rotated the engine until both intake/exhaust lifters on cylinder 1 were at the bottom. Put in my new Autozone 6.390 pushrods in and got the rockers to 0 lash. Then, set my torque wrench to 20ft lbs. It took about 2 full turns to get them to torque.

Replaced the new pushrods with the stock ones. 6.248
Got the rockers to 0 lash
Don't recall what it took at 20 ft lbs to get to torque, but was within spec, however, I could still move the pushrod up/down a bit after rocker arm was at full torque.

My theory is I need about a 6.3 pushrod. However, they're pretty expensive for just a stupid rod :) Wish I could try one before buying the whole set.

Now I understand about the adjustable pushrod to measure a perfect fit-- however, whatever number I find that's perfect, I think either that size won't be available or will be like $200+ which is crazy where the stock are like $90. Also, given all the youtube I've watched, everyone seems to be doing it differently which leads me to think most have it wrong anyway and still getting by :) At this point, I'm trying to find another pushrod of the same type but smaller size I can once again try.
 
#275
When you say you can still move the pushrod up and down a bit, do you mean they are loose or you can " push" on it up and down a bit..
I found a set of 6.250 with a 080 wall thickness at summit or Jegs I used.....
 
#276
I can move it up/down a bit.

That's the next thing I wanted to try. If the theory is true, stock ones are 6.248, NAPA sells one that's spec 6.25. Maybe that'll help? though I think there's more slack.

I also read that different manufacturers measure the pushrods differently. There's like 3 ways. I don't want to learn that I spend $200 on a set that has a spec of 6.3 but is actually 6.275 :)
 
#277
If you had ZERO lash, then you had between 1/4-1 full turn to torque, ( 22 ftpds) then you are set...
Your lifters need to pump up with oil pressure..
I " think " that is why your getting some lifter movement after you have done this...
 
#278
Right now, I think my pushrod is too short. I am torqued to 20 ft lbs but not because the rocker is pushing on the pushrod, but because the rocker bolt has bottomed out. The slack is not much, but it's there. Yes the oil will pump up the lifter but isn't that what goes in to the preload?
 
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