2nd hand lifters in worn/mismatched lifter galleries? Does the lifter look like it could have jammed in the open valve position.?
I don't mind using second hand myself but I probably wouldn't swap from motor to motor with particular wear items.

 

See, that's the thing: If it were a single lifter/valve causing me issues, I'd assume that were the problem. But it was all 16(12 of which were clear marks) valves which were touching.

Unfortunately, I wasn't able to get it back together with empty(air-filled) lifters and give it a test run this weekend, so I don't know if that would have fixed it. I'm leaning towards /not/ though -- I'm thinking that as a valve wears, the valve stem becomes taller compared to the rocker arm(when seated closed), which means that a lifter will start out 'fully extended' and over the life of the engine it will slowly shrink; if it didn't, the worn valve would not seat anymore.

If this is true, then my lifters(which came from running with a /more/ worn set of valves should easily have taken up the extra slop and worked right... and this problem could only have been caused by it taking up /too much/ slop and driving the valve into the piston.
Also, I know none of them got 'stuck', because when I tested this engine before putting it in my truck(see the video in the first post), I had the valley pan off and was watching them all move.

Now, this leaves only three options:
1. Cam. Perhaps the cam is either wrong or incorrectly ground?
2. Pushrods: These came out of this engine I'm working on. They are straight. But could they be aftermarket/longer pushrods someone put in? I'll have an answer on that tomorrow.
3. Rockers: Again, these came out of the engine. Could they be higher ratio rockers? I'll have the answer tomorrow(well, my dad will compare them for me and let me know what he sees).

I don't see anything else. If I have to, I can always put a shim under each rocker-seat; effectively reduce the max height it can push open, but I don't want to do that until I know /why/ this happened in the first place.

 

Sounds like your on track, I hadn't read/noticed before that you had seen marks on the piston, that's a huge clue.

Can you put your old cam back in?

 

Yes and no - I have a known-good cam from my other engine, but the one from this engine was the core that got sent out to be reground.

Edit: Just learned -- The push rods and rockers are stock.
This means either the lifters, cam, valve stem height... or a combination of those.

One thing I'm going to try is shim the rocker arms and see if that works.

 

It's really starting to sound more and more to me like a cam issue. Both the very high lift and how they make it. To get higher lift out of a regrind they have to reduce the base circle. This means the lifter travels further down not further up then stock. If the lifter is traveling down far enough that it's coming to the top limit if it's hydraulic adjustment then the valvetrain will be noisy, even more so if the lifters you reused can't reach the top of there adjustment do to internal varnish buildup. They may even get stuck at full extension. These issues combined with the hi lift, or maybe just cause of the high lift may cause the valve to open too far and may not close all the way.

 

That issue will be solved; I've cleaned all the lifters. Somewhat surprisingly, I found no varnish or other stickyness; just oil. And all of them appeared to be in good shape internally.
Of course, now it's filled with air, so I don't know how it'll work until they fill with oil.
I have PMed typefour and asked him about the cam; I need to know before Friday whether the cam is usable -- right now it's trivial to pull it and stick a stock one in, though I really don't want to do that(I mean... the Typ4 cam sounds so cool, and should give me a good 10% better performance)

 

Were the heads or block faced? That could be another cause if too much was taken off either.

 

Nope; I did have to aggressively clean the old headgaskets off with a wire wheel, but that can't have taken more than .0001 off, if that...
The only thing I did to the heads was have them hot-tanked and a new set of valves ground to match, and the valves are apparently within spec*

* After taking the heads off and cleaning the gasket, I checked the deck-to-valve stem height which should be 5.720-5.730. I did this with a test indicator in the quill of my manual mill; used the knee to get my nominal 5.725 and then checked each with the indicator. I found that most were within spec, though a couple were up to .02 higher/taller -- I'm guessing that they wore in to where they seated correctly.
Also, the ones which were out of spec on the high side had no worse or better pattern on the cylinder face than the ones which were at the minimum of the spec.
I checked the head that came out of this engine and they varied by at least that much one valve to the next, so I'm not too concerned.

 

I was revisiting this thread n advance of starting work on my own unknown 7.3 that I bought for the turbo. Also considering a Typ4 cam. I know from your later thread that you ended up with a rebuilt motor from a machine shop. What was the story on this project? Did you figure out why the valves contacted the cylinders? What about the cam?

 

I wonder if Delta Screwed up and sent Russ one of my cams?? The valve lift on my cam is .410/.412, and you are getting .411" with .274" of lobe lift. If you were to have installed my cam a tooth off (Meaning advanced, or in the stock location, dot to dot), you could very well come into contact with the piston.


Its obvious that its marked 206 (That's the torque cam, my grind is a different number) but the lobe lift is way off. I wonder if they got it confused with my grind.


I would put it back in the engine and degree the cam, post the numbers. We would be able to tell then.

 

I've got the cam handy, but degreeing the cam in the engine won't be possible for a couple of months -- too much snow between engine and shop.
However... I'm thinking about 'degreeing' the cam by itself -- stick it in the 4th axis on a mill at work, use that to give me my angle, and use an indicator in the spindle to find my height.
If I were to do this, I'd have to use the middle of the keyway as my reference point(0 degrees), and then all of the numbers doubled(to correspond to crankshaft rotation), shifted etc.
I would be able to provide angles, direction, pictures etc... but I'm not sure I know enough to convert the angles.

Any thoughts?

 

I have a question did you check you valve lifters could you have a bad one? and are they setting in the block right?

 

Do note the date on the last post here... Almost 2 years ago.

I've tried a couple of times since to get the cam working in another engine with varying issues.

That being said, I'm thinking that this was a combination of two things:
1. This cam is, as best I can tell, a J2/idi performance stage 1 cam, not a Typ4/Russ torque cam. The difference is that the J2 seems to have a little more lift... and be designed to run 1 tooth off. It /should/ have more or less worked dot-to-dot, though, but....
2. Valve recession. I've recently learned that valve recession is absolutely key when working with IDIs. Stock, you have perhaps .030 between the valve and the piston coming up, and if you have tolerances stacking up(piston/conn rod/bearing slightly taller than normal, valve on the low side), you can get contact.
These heads were "rebuilt" at a local place who, I'll bet, did not know/check the tolerances. They just put new valves in, got them at the right angle, and called it good. Unfortunately, this doesn't seem to be good enough - you need to actually machine the valves or seats down enough to meet the recession spec. Or bad things will happen.

Now, with a stock cam with less lift, this might be less of a problem, but when you put in a cam which effectively has the most lift you can get away with before piston/valve contact anyway... you can see where being even slightly out of tolerance will cause valve contact.

 

The J2 cam and R&D Stage 1s are actually different cams. The J2 is a bit closer to what the R&D Stage 2 is.


Also sorry to hear about your engine. You can't win...

 

Didn't know that.
So... who makes the J2 cam then?