Id love some nice shiny heads. Dont think theres anything available right now. Wonder if the new heads could be drilled to accommodate the 430 style oiling.. Cant help but wonder what caused that guide to wear like that. Probably should pull both heads and go through them as a set.
Available but maybe more than you need Just do a standard rebuild on what you have. Glad you found it
If you have the fundage, going through both heads, new guides, valve job, clean up mill, and maybe some bowl blending/smoothing, not too much cost for the returns.
Wow never saw that much winky winky . Briz good meeting you at the car show. Glad you found the issue.
Thats almost like a 11/32” valve was put in the stock 3/8” guide! I would for sure pull both heads and disassemble them to inspect everything!
I did the full port n polish job back in 11 or 12. Put in bigger valves with smaller stems. The cost should be min to go through these assuming I dont have to buy any new valves. Now finding a local place that will do the work may be another thing completely.
What was used when the heads where rebuilt, a guide liner, or a solid guide? and also where the heck did all of that material go? I wonder how the cylinder is going to look once the head is pulled. measure all the valve stems carefully. Anything more then .001” of ware showing up anywhere on the valve where it rides within the guide and the valve is toast!
I really dont remember but I think we used bronze guides. We'll probably see later today what the innerds look like if I get that far.
Its odd to me that there is so much play all around the valve stem. If it was due to side loading the valve you'd think it would be worn in an oval shape.
The guide liner must have fallen down. Its either smashed into the valve head or it broke apart and went out the exhaust.
I ALWAYS put a 1/8th. inch lip at the bottom of the guide to help hold the guide liner in place. The guide liner coming out of place has been a very real problem over the years because of the sideloading of the valve. Greatly reduced with roller rockers. Tom T.
Got as far as pulling the hood. Wife had chores for me and then the daughter needed the oil changed in her Honda. Tomorrows another day
Yup. Are you sure that the head GOT guidework? Didn't just slide the new small-stem valves into the old big guides and didn't notice that they're all sloppy? Did the new valves get new keepers and retainers? OEM Buick keepers and maybe the retainers are "special"; replacement valves would almost certainly require new keepers if not retainers. Is there appropriate oil supply to/through the rocker shaft? Shaft not plugged with sludge? That guide is wiped. New guide(s) means grinding the seat(s) so they're concentric. Multiple seat grindings will sink the seat, and remove any hardened layer (deliberately hardened, or work-hardened through use) on the head casting, which probably means hardened insert(s) needed. And if you can save the valve from the known-bad guide, it'll be a miracle. I'd expect stem wear, and the face is likely to be beat-up. The chances of metal fatigue where the head meets the stem are tremendously increased, because the valve will be bending to fit the seat every time the cylinder fires, AND it would be running hotter'n hell due to poor heat transfer to the ill-fitting seat and guide. In my shop, that valve would be scrap, without question. How the rest of the guides are, and the valves therein, will have to be determined during disassembly. I would not count on a "minimum cost" repair until after that inspection is done. And we haven't begun talking about the rocker arms where they push on the valve tips yet. Again, that'll have to be inspected during disassembly.
Like stated above. been running these heads for 10 years. Have no oiling issues. Stock rocker bar and the 430 rockers dont show any excessive wear on the tips. It does run lash caps. had hardened seats installed when they were ported and rebuilt. You are correct, only time will tell. I'll talk with the guy that did the work this week to get his take on it.
Heads are off. Fished the valve out and put it back in the head for safekeeping and reference. On the surface they dont look bad and the cylinders are clean. Pulled each lifter and they are clean smooth and shiny. That rules out a bad cam. So I have an extra 290-08 and lifter set for just in case. Does look like its been running fat and much blow by judging by the color on the piston tops and amount of grime in the valley. Had this completely apart this time last yr and it was spotless when I reassembled it.
Once you start getting enough oil into a chamber then during the overlap period and with enough run time it will make its way back to the valve Intake plenum and then start to show up in the other cylinders and there spark plugs.
