IC 392 Valve Train issues

Got er running late last night. To solve the rocker/stand clearance issues I had to take the assy out and adjust some of stands. The hole in them is pretty big and there is room to adjust side to side and still get the bolt through. Also, I spun the engine over by hand to confirm that the loaded rockers had play when they were unloaded.

Before starting I verifyed oiling. I had very good flow at all rockers. One thing that I noticed was oil did flow slowly out from under the hollow oiling rocker on driver and passenger side. I loosened all the stands up and retorqued them, but it still happened. I guess the metal to metal interface of the stand and the head is not oil tight. The flow was very good up to rockers though, so I decided that it should not be a problem.

The valve train sounded really good and quiet. It seems to idle much stronger now and respond to throttle quicker. Also the exhaust note is much lower and stronger now. I didn't drive it much, just around the block to the other side of the street, no more parking tickets!

Is there any special driving mode I should follow to break the lifters into the cam?
 
There were obviously some design changes in the rocker stands over the years...but the p/n on the "different" stands did not change. The mounting hole diameter was one of the changes.

You must not observe any oil leakage from the base of the oiler stands...that will allow reduced "calibrated" flow to the rocker shafts. That location must be oil tight.

If some po has been into the motor, then they might have cut down the base of the rocker stand(s) in an attempt to create additional lifter preload. All too common, that is something I check on all the reconditioned stands I prepare.

Lifter "break-in" on an in-service cam...I run the motor at fast idle for 30 minutes then drive it. Are you seeing lifter/push rod rotation at all positions?? Rotational speeds May vary quite a bit, that is ok.
 
The rocker stands were all provided with the reconditioned shaft/rocker assys I received from ihon. I inspected them and none of the bases of the stands looked machined. They all had the semi-rough cast finish. The surface at the head where the oiler hole is looked flat.

If loosening and retorqueing the stands didn't work do you have any ideas on how to get the rocker to seal against the head? Maybe the shaft hole in the stand is off effectively making the stand too short?

I did not run the engine with the valve cover off, so I did not observe lifter and push rod rotation. Is this a "normal" check that should be done? It is possible to observe the lifter rotating?
 
If the stands showed evidence of machining marks on the base (flycutter), then they have not been cut down.

If the stand bolts are over-tightened, that will crack the surface under the thick flat washer and allow oil leak-by also. So it's a fine line between tight enough to seal the base and not crack through the bolt hole at the top.

With the engine running and valve covers off, you should see all push rods spinning slowly, if the push rods are spinning, then the lifters are spinning in their bores also as they should be. The johnson lifters have "crown" machined in to create that effect, as long as the cam lobe has a slope ground in also to impart the spin.

If measurement proves some of the stands you have are not the right stack height, then call Jeff and he'll send me a shipping order and I'll shoot out some more stands to ya asap from my location.
 
I pulled the rocker assys out for measurement on a surface plate. The oiler stand was about .010 in short, there was a clear gap. This is what was causing the oil to leak at the head/stand interface. In addition the stand at the rear of the shaft (relative to the head installed on the vehicle) was .004 short, and the stand at the front of the shaft was .003 short. I am really disappointed in the quality control of this reconditioned shaft That was supposed to be a bolt-in item, cost me a whole Saturday of extra wrenching. At some point the stands on that assy were machined down, but there is no evidence because as part of the reconditioning process the stands are bead blasted.

To solve the problem I measured the shaft hole to stand base distance of the stands from my old rocker shaft assys, checked them for flatness and picked the best ones to match with my "reconditioned" assy. Luckily my old stands were good, so I changed all three of the suspect ones. Checked the assy on a surface plate again and it was very flat, no gaps. I believe the reconditioned shaft is built up slightly over sized because the rocker stands were very difficult to remove and to turn to adjust the bolt holes and to align the bases. The oiler stand had to be driven off carefully with a punch, and driven on with a piece of pipe.

The rocker shaft assy was reinstalled and oiling checked with the oil pump drive tool. No oil leaking around the oiler stand. Just to be safe I pulled the other side to check it on the surface plate. Thankfully that one was good, so I put it back together and confirmed its oiling. There was a slight seep at the oiler, so I added 5 lbs of torque to all the stand bolts and then it looked good.

While it was apart I was able to see witness marks on all of the new push rod ends that confirm they are turning while the engine is running.

Got it all together sat night and have put about 35 miles on it so far. It sounds good, and runs very well. I hope it continues this way for a long time.

One question. I heard that the ratio of the intake rocker is different between the welded (1.5) and boat (1.6) style rockers. Is this true?
 
Moot,
sorry to hear you has issues with the rocker stands. Call Jeff tomorrow and he will take care of it. I know things do go wrong sometimes so all we can hope for is that things are made right. I know Jeff will or who ever will.

Good thing to come of this is your rig is happy and oiling. You played a big part in getting things right. Glad you didn't give up and kept on trucking. Thanks for sharing your project with us..

The rocker ratios are different a bit. The welded ones are different between the intake and the exhaust. Opinions differ here but I measured both and get about 1.7 and 1.75 for the welded and the overall opinion on the boats is they both are 1.6. The ratio difference will mainly effect lift a bit but only a small difference in duration @ .050.

I have a fixture setup that I intend to use for a rocker arm ratio validation study on both styles. I will measure the ratio from just opening to fully open and chart the data points for the record.
 
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I've found after looking at way more than 100 rocker stands (useable) in the last few days, that they varied somewhat from the factory as to "height". And I've also experienced the same leakage at the base and had to swap some stands around to cure the problem. But I've not ever had a new (nos) stand or two to compare that has not been "crushed" by being installed previously.

The "crush" is why they are difficult to remove and install. The rocker stands I recondition are all individually honed and inspected.

Four sets of nine reconditioned stands (two oilers, seven non-oilers) are on their way down to ihon tomorrow along with a bunch of other parts. All have been honed and test fit on a new rocker shaft. I do not glass bead anything, I mechanically clean all parts by hand prior to inspection for quality.

The reconditioned parts you received were provided through a different supplier, not from me. We are just now getting our own source parts into the inventory at ihon.

We're sorry you have experienced an issue with the parts you received, so replacements will be on the way to you once Jeff receives 'em from me. Or he can send me a packing slip and I'll drop ship a set to you directly. And all nine stands you receive this time will match for installed height...any I find that don't match are set aside and not shipped for any use. Once I have a set of nine "mis-match" stands, then those all get machined as a set and and used on my personal stuff, those never get shipped to a customer. The replacements will also all be the "large bolt hole" version so that you May adjust for side play as needed. About one half of our current reconditioned inventory are drilled with small holes.

edit: one of the oiler stands I've prepped for you will be a "small hole" version. Use that one to index the shaft from in relative position to the head. Every "set" of nine stands includes two oilers...the reason for that is so that the shaft assembly can be used on either side without having to disassemble/reposition any stands. Also...the "second" oiler stand (actually both) is cut away at it's base to clear the head of the head bolt, there is an interference point when mounting to the head if ya don't have the "cutaway" stand in the correct position.
 
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