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Rolls V-7?

DrEntropy

Great Pumpkin
Platinum
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Corniche wouldn't idle, compression in the A4 hole (starboard bank, rear cylinder) varied wildly. Sometimes on first stroke it'd go to 120 then fall off, sometimes nothing. always leaked down quickly. Yesterday the rocker cover came off, the exhaust valve is apparently a bit out of adjustment... :oops:

Not sure if it has a collapsed lifter (a notorious problem) a bent rod, maybe both. The exploration continues.

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EDIT: My bad. That's the intake valve for the cylinder.
 
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From the look of the valve tip it has been this way for a looong time.


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Partner pal just found the "what" for the miss, now must find the "why." Lifter is fine in its bore. We're likely to see the head removed before knowing just what caused the bent push-rod. Seems the valve galling/sticking in the guide would be about the only cause. Owner of the car has to make some decisions...

This is a stopping point 'til some time next week.

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Should have said it wouldn't idle as smoothly as it should. Running off idle it pulled like a mule on steroids in spite of one dead hole. At some point in the car's past (it hasn't been driven much in years, if not a decade or more) someone convinced the owner to get rid of the SU setup for a Carter 4-BBL... likely to (erroneously) eliminate or mask the miss. It would almost smooth out as the Carter carb was fiddled with. No idea who/when that swap was done, the SU's and intake are MIA. A real shame.

We'd seen the car at our shop once in the late 90's for brake work, never after that. No clue whether it'd already had the induction swap then or not. But I think we'd have noticed an un-Rolls like idle, that kind of thing wouldn't have been ignored. It would have at least been noted on the invoice, our copy has no such note.
 
Partner pal just found the "what" for the miss, now must find the "why." Lifter is fine in its bore. We're likely to see the head removed before knowing just what caused the bent push-rod. Seems the valve galling/sticking in the guide would be about the only cause. Owner of the car has to make some decisions...

This is a stopping point 'til some time next week.

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Yowee that mama is BENT!
 
Valve moves freely in the guide, Marvel oil down intake to cover the valve head and no leaking past it. The mystery cause remains.
 
I wonder if the gap at the lifter allowed the rod to jump out of the cup at the bottom - the way it is bent sure looks like it was pushed down on the edge of that cup - there might even be a witness mark.
 
Possible, JP. Tho no witness marks on either end of the rod. Funny thing is, it didn't make any outwardly audible noise or rattle while running, even using a stethoscope. It appears the lifters were "substituted" with something other than Rolls ones at some point, they don't have the right oil galley holes. There was a Chrysler lifter that fit, a Rolls Owners Club bulletin was warning against their use, that was decades ago. But we're uncertain what this set is just yet. Time will tell. The biopsy goes on. :unsure:
 
Now it is OFF with its HEAD(S)!!

Both hydraulic pumps were leaking, the accumulators as well. Some really "creative repairs" done to the A/C system, wiring butchered, bent up steel and aluminum piping to accomplish bypassing original evap valve and who knows what else. No refrigerant to recover tho.

That bent rod will NOT come out without removing the head first.

"We must go further!"
 
Any update?
Heads are off, going to machine shop. Hydraulic pumps are two different types, one original, both really crudded up with goo to the point it was difficult to get them apart. On top of that, the replacement one had apparently had its castellated nut tightened with a CHISEL(!). Took time to file the chisel-displaced material smooth enough to use the tool to remove the ring nut. It was so tight and corroded the tool was the only way to undo it. Pumps and accumulators are cleaned up and instead of rebuilding here, they'repacked up and going for exchange. That saves hours of fussing.
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Welcome to my world, Doc.
Been in it for a few decades now. Seems the hydraulics on these cars are ALWAYS the most neglected system. Or the most cobbled.
 
Now for the sorting of the loom! A LOT of impromptu "free expression" with regard to the wiring over the decades, apparently. A genuine nightmare.

Told partner: "Cut the BLUE wire!!!" :LOL:

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