After enduring funky health issues and finally back and doing stuff, the Coronavirus now has me unemployed with lots of time on my hands and little $. Got around to tearing down the original 292 out of my ‘58 Ranchero. The heads are big G and look ok. Plan on having them cleaned and magna fluxed to be sure they aren’t cracked. My main question is should I reuse the original valve springs and valves and poor boy it? Never have done a y block before and looking for wisdom in this area. I have a second runner 292 with mismatched heads and was planning on swapping them out once these are done. Thanks.
What’s your plan? Is a machine shop involved? Did it smoke a lot after you came down a slight grade and stepped on the gas? If not your guides are ok and may last a lot longer than most think; clean everything with a wire brush, lap the valve and seat, install new seals, and drive it some. I’ve had a shop replace or install “false” guides and lapped in the original valves and was ok. If the valves need grinding you can have the shop do it all and you assemble if you have the tools. Good luck.
Way too many heads get a “ valve job” when not necessary! Everytime a machine shop grinds on your valves and heads, material is removed. By all means do a valve job if really needed. Like Jimmy Six says, check them out, clean them up, lap them in, check again. I have done many “ overhauls” and didn’t have a “ valve job” done, with success. Bones
If there isn't a lot of guide wear and it is just a driver, I'd grind the seats and faces, install seals and run it. I am not a fan of lapping valves as that doesn't address valve angle and seat width. Fortunately I have an ancient valve grinder and seat stones/pilots/driver setup. But, I'll be the first to admit, I'm cheap. Given my past experience with Y-blocks, which includes very few that were found to have cracks, I would do a close visual inspection and skip the Magnaflux.
Instead of spending the money for "Magna-Flux", go to your welding supply & get a "Dye-Chek" kit for around $35.00+/- , FOLLOW THE DIRECTIONS, & you will be able to check your heads(& probably the next 10 sets as well!!) You will find it useful for checking for cracks in non-ferrous metals as well. Just another "low-buck" tip for the troops....
You guys have all the answers!! Should have let you know this as well. Ranchero sat in a field for 30 years or so WITHOUT SPARK PLUGS IN! Seized like no other too. Cylinders had surface rust and one cylinder had what appeared to be the blown head gasket prize. Pan off and crank etc dry, only oil. The $100.00 runner runs ok, heads are mix matched. Thought heads swap and a good minimal cleaning, I’d have a less worrisome power plant till I return to work and throw $ at rebuilding the block. Thanks again fellas!! W.
Nothing wrong with mismatched heads. We were running a 351 Cleveland in our 1/2 mile dirt track 1982 tbird a few years ago, and one head cracked from overheating. So I put on a 2v head because that's what I had. So one 4v, one 2v head. Lap time was Quicker!
spray them with oven cleaner. rinse with hot water. make certain everything is real clean . lap the valves install new seals.
Depends how picky you are, though valve springs are not expensive and are often overlooked. They have an "installed height" spec, shim them up as required to achieve this.
A little trick I learned that makes lapping the valves in much quicker. Just put your lapping compound on the valve and stick them in place and chuck up the valve stem in your cordless drill. does a nice job , just pull on the drill a little for pressure. I did a 64 Mercury 390 that had been parked for 30 years in a garage so it hadn't been exposed to the weather . The valve guides were good and it had some pitting on the face of the valves so I just lapped them in and put new valve stem seals. It has been towing a nostalgic travel trailer for 4 years now all over the south.
But it will show you the seat width...so you can see if they need to be ground, or not. The answer to the original question, is "it depends". If the heads are in decent condition, and you don't plan to put more than 10-20k miles on it, then you can get away with quite a bit of "poor boy". If things are really wore out, or you want it to last forever, then you kind of have to spend money. I got lucky on the 292 I overhauled a few years ago, someone had done a valve job on it not too many miles before I got it, so I just cleaned the heads up and put them back together, and it worked great. But I did need to change the cam bearings, and put rings in it.
Top end oiling can be problematic for a number of reasons on Y blocks. I'd tear down the rocker arm shafts and look for signs of wear from lack of oil. If so, I'd look real close at the valve guides, and the rocker assembly. There's an oil passage from the head to the block and it's worth looking at that on both engines if you're swapping heads. Those can be relived. There's a pad on one end of the head, with a standard factory dimension, measuring that will let you see if they've been milled before, and how much. Heads crack for a variety of reasons, but over milling non posted heads and higher compression is a common y block deal. Here's a start on head info. I don't remember the stock pad height, but if someone here doesn't, someone at yblocksforever will. http://www.ford-y-block.com/cylinderheadchart.htm http://forums.y-blocksforever.com/Default.aspx
The “ book” tells you to not “ spin” the valves while lapping them in. If you spin them , it can hide bad spots, says the book! I have not really wrapped my head around how it hides bad spots..... but, the book! I’m sure it’s correct, because they actually make a hand cranked machine that turns the valve about 90 degrees back and forth. You can apply pressure and turn the valves back and forth, and get a good surface real quick with these little machines. I have heard they have electric powered ones, but I have not see one. I just use my old hand cranker. Edit: went on Amazon and found an air powered one for $47! PS: after I lap my valves , clean them, inspect them, assembled the head, I test the valve to see it it will hold gasoline. A properly seated valve will hold gas. Bones
Yeah I read the book that said that in high school auto shop in the 60's . I think it was chiseled out on a stone and Moses carried it around. I have been using the cordless drill trick for years on street cars and race cars. I always put a spark plug in the hole and fill the chamber with mineral spirits and let them set over night . If they are full the next morning they are not leaking. I used to race round track enduros . 500 laps on a half mile dirt track in a stock motored car. We would pull a car out of the junkyard and do a valve lap , dingle berry hone job . New rings and bearings .New timing chain and oil pump, a new stock cam and lifters. A set of 29 dollar z-28 valve springs and let her eat. It was about durability not so much speed as you put a hundred cars on a half mile track racing for $ 5,000 and see how much speed you can get. We never had an engine failure. We have had to have a front end loader put the car on the trailer because of a crash, but otherwise they always finished and always passed tech at the end.
That's a good point brought up about rockers & shafts. Loosen up an adjuster and slide the rocker over and inspect the underside of the rocker shafts, this is where the load is. They will likely be scored and galled badly due to lack of lubrication.
Maybe it didn't apply to the y-blocks, but wasn't there a trick that involved rotating the rocker shafts 180° to put the unworn surface on the bottom? Maybe it required some other modifications to assure getting oil flow to the valvetrain? For that matter, maybe it worked for a Studebaker . . .
You mean Squirrels old avatar pic,,,,,? Yeah,,,it was cool . His expression looked like ,,,,,, “oh well,,,,who cares “,,,,LoL. Tommy
Old but very effective tool which is for valve lapping. One step forward and two steps back. It was one of fathers tools I kept. He was born in 1913 and passed on in 1963.
Hmmmm I replied to y’all in thanks and now it’s gone?!? Try again. Thanks Fellas!! Car was a field find w/ seized 292. No spark plugs in the heads when found and found spark plugs welded by rust in it’s bed. After pulling it down, found evidence of a blown head gasket and those rubber temp expansion plugs!! Anybody’s guess how the block is as it had some water in the passenger side of block to head. Car has been garaged over the last year so water has been in it for a long time. W.
I still remember one day in junior high shop class, small engine repair. Mr. Meins, our instructor, at one point produced a small green metal can of Clover brand compound and a showed me how to lap the valves in an old Clinton engine. It even started and ran when I was done!
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