Anyone ever try that? I got one jug that shows zero, nada, zilch for compression. Maybe I'll have to come up with a suitable piston as well. I know it's a taboo kinda thing but has anyone ever done that just to get by for 6 months to a year until funds afforded a complete rebuild? Downside other than having to pull the engine again in less than a year?
Rednecks, white trucks and Pabst Blue Ribbon beer!
A cylinder with no compression at all probably has something else wrong with it than worn rings. I suppose it's possible the rings (or piston) is damaged, but I'd first pop the valve cover and check the rocker arms and pushrods to make sure they're not broken/bent. You can't compress something that ain't gettin' into the cylinder in the first place because the intake valve won't open.
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-O-----O- Keith
'67 F-100 2WD SWB ~ '69 F-100 4WD SWB w/7" chop ~ 1975 F-250 Ranger XLT Supercab Camper Special My '67 restoration video -> Posting and you!<-a MUST watch for all!!
I have a friend who could get away with it. He once sanded a bearing that was so tight it locked the engine up when tightened until the engine would turn, finished the engine and ran it... that was something on the order of 10 years ago and he drove it for about 5, last we heard the car was still running. If I had done it, it would have put a rod through the block in 10 minutes I have no doubt.
Antidotes aside, while I see no reason you could not re-ring just one cylinder, I also do not see any real good reason to do so, rings and bearings are not that expensive and you will be one set of head bolts away from having the other head off anyway...
As Keith said if you have one completely dead cylinder, particularly if oil does not improve it it is probably valves and not rings anyway.
I was thinking flat cam lobe, broken rocker, or a collapsed lifter to name a few. The rods were straight as I remember when I pulled them out. I didn't see anything (though I wasn't looking) wrong with the rockers either. I would suspect that a lifter would make noise, right? But maybe not a flattened cam lobe? I dunno, I guess some wrenching is in order no matter what I find.
Rednecks, white trucks and Pabst Blue Ribbon beer!
Have you thought about getting a used engine to get you by. I know several 360's have been put up for sale and most have been inexpensive. By the way where do you live,someone may have one and live close enough to help you out. John
1968 Ford Ranger Lb
2007 Harley Electra Glide Classic
Actually HD, I was planning on this engine getting me by until I could come up with a 300 sick to put in it. At this point unless a 300 just happens to fall into my lap, it looks like a rebuild/partial rebuild is in order for the 360. The truck may have just made my mind up for me! I'll tell you guys what, maybe I'll just freshen up this 360 and if it makes enough of the right kind of power, I may just keep it. As stated before, I'm not really looking for a power house but I don't want to be let down when I do need a little "umph". The 300 six would have the edge only because of a slight gain in mpg and the fact that the truck came with a six in it. As I've gotten older I find that I like having older rigs that are as stock as possible. Besides you really don't see many of them with the original six in them anymore. Everyone yanked them out to put 390's and such in them.
Last edited by Fordlorn on Fri Oct 31, 2008 7:44 pm, edited 1 time in total.
Rednecks, white trucks and Pabst Blue Ribbon beer!
It'll be in the valvetrain. Rarely will you see a piston cause zero compression. The piston would have to be broken (which would have caused a noise) or have a hole in it.
Exhaust valve to be precise, these old engines were never built for unleaded fuel.
Do a compression test on all cylinders and if they are all even, not sure how high they should be (130-150psi?) pull off the rocker covers and crank the engine over by hand until both valves on that dead cylinder are close and stick a rubber tipped blow gun in the spark hole and see where the air comes out. I would bet on the exhaust.
If you are going to rebuild heads for it use the 75/76 heads that came with induction hardened seats, different valves. 360/390s anyway.
thats the heads we used when we built the Merc. 7 years and no problems yet. it doesn't work for a living anymore though.
cheers to lower gas prices,, down to $.90 a litre here was 1.25+ this summer
Collecting 67-72 Ford/Mercury trucks since 1980, collecting 73-79s since 1990 when the 67-72s started drying up. Now I'm culling the herd. None of my 67-72 will ever be for sale! They will need a big hole in the ground.
Update. I finally pulled the offending head off this morning, after I ruled out the flat cam theory. I pulled the valves in the bad cylinder and can find nothing obviously wrong with either one. I did notice however, that the exhaust valve seemed to be slightly receeded. I doubt it could make for a dead cylinder but it was slightly noticeable. Can't find anything wrong with the piston or bore, so I guess I'll have to rule that out. The stems were a little sloppy in their guides as well but nothing I haven't seen on other high mileage engines that still ran decent. The springs on the two questionable valves felt about as weak as the rest of the springs on the head, so I can't blame the springs either, don't know if springs could cause this kind of problem anyway. Anyone know how much seat recession is allowed? All the exhaust valves seem to be in a little too far anyway, just by looking at them.
Rednecks, white trucks and Pabst Blue Ribbon beer!
Fordlorn wrote:Update. I finally pulled the offending head off this morning, after I ruled out the flat cam theory. I pulled the valves in the bad cylinder and can find nothing obviously wrong with either one. I did notice however, that the exhaust valve seemed to be slightly receeded. I doubt it could make for a dead cylinder but it was slightly noticeable. Can't find anything wrong with the piston or bore, so I guess I'll have to rule that out. The stems were a little sloppy in their guides as well but nothing I haven't seen on other high mileage engines that still ran decent. The springs on the two questionable valves felt about as weak as the rest of the springs on the head, so I can't blame the springs either, don't know if springs could cause this kind of problem anyway. Anyone know how much seat recession is allowed? All the exhaust valves seem to be in a little too far anyway, just by looking at them.
sounds to me like you found the problem without even knowing it. That recessed looking exhaust valve is probably not sealing(contacting) seat when cam lets it back up again. Valve train movement isn't really very much, and when the valve seat is burned up as well as the valve.. there goes your compression. since you already have it apart, find an old used head and tear it apart, see if any of the exhaust valves are recessed, if not, clean it up and use it.
to do it right you should take your old head and get it cut down for hardened seat inserts and get that head rebuilt. It depends how much you want to spend.
Hey nothing wrong with diagnosing your problem without even realizing it. We nevr learn anything unless we try right.
Collecting 67-72 Ford/Mercury trucks since 1980, collecting 73-79s since 1990 when the 67-72s started drying up. Now I'm culling the herd. None of my 67-72 will ever be for sale! They will need a big hole in the ground.
I got one jug that shows zero, nada, zilch for compression. Maybe I'll have to come up with a suitable piston as well. I know it's a taboo kinda thing but has anyone ever done that just to get by for 6 months to a year until funds afforded a complete rebuild? Downside other than having to pull the engine again in less than a year? 
sounds to me like you found the problem without even knowing it. 
That recessed looking exhaust valve is probably not sealing(contacting) seat when cam lets it back up again. Valve train movement isn't really very much, and when the valve seat is burned up as well as the valve.. there goes your compression. since you already have it apart, find an old used head and tear it apart, see if any of the exhaust valves are recessed, if not, clean it up and use it. 