Can you help with compression #'s

[J4intheGorge]

The truck is built and I love looking at it in the driveway. Now if I can only get it running. Here are my compression numbers:

#1 - 55 psi, 65 after oil down the hole
#3 - 155
#5 - 155
#7 - 160
#2 - 155
#4 - 155
#6 - 155
#8 - 155

Can I make this truck run well without a rebuild. Is it worth tearing into over one low cylinder? If not, should I rebuild this one or find a replacement? It runs like heck but I think it's more than just because of one cylinder. When you guys swap motors, what do you put in? Another 360? Anyone in Oregon have a motor they're getting rid of? I'll post a pic soon and you'll understand why I want it running. Thanks much.

[FSJ Guy]

AFAIK, no change in pressure with/with out oil and low pressure like that is indicative of bad valves or a worn lobe on the camshaft.

Does it run now?

[pineymike]

Does it smoke? In a pinch{no money} you could make it run fairly good on 7 cyls I would losen the rockers and pull the plug wire,It's dicey tho mite cause more damage?If your going to replace the engine why not?:eek:

[Herk]

Running on 7 cylinders you're only sending 12.5% of your gas out the tailpipe. About 5 cents a mile or 20 MPD (miles per dollar). A new engine is $3000 or so, giving you a 60,000 mile break even point. Since it will blow up well before then, just run it.

May the innocent babes of the environmentally conscious liberal scum choke on your fumes.

[shackwrrr]

well if you loosen the rockers so the valves dont open then hows that cylinder going to suck anything. then hed be gettin 12.5 increase in fuel mileage

[Herk]

Until a lifter comes loose, then he gets a 100% loss in oil pressure.

[J4intheGorge]

Does it smoke? In a pinch{no money} you could make it run fairly good on 7 cyls I would losen the rockers and pull the plug wire,It's dicey tho mite cause more damage?If your going to replace the engine why not?:eek:


It doesn't smoke out the tailpipe but smokes at the exhaust manifold which is on the replacement list. I can get it to fire and run real rough in the driveway. Can't drive it though without a bunch of spitting and coughing (the truck of course) which is after the carb rebuild. I may have someone look at it. I want to be able to drive it to town (freeway) and wanting to off-road the #@$! out of it goes without saying. If I loosen the rocker won't it be all sloppy in there? I just don't think a rebuild is worth it when the 360 is so easy to come by, among others. Does PCV, charcoal canister, air cleaner hoses (seem to plug in to the bottom back of the air cleaner, all make a difference or should it still run well enough to drive it?

[shackwrrr]

acually someone may have been in there and tightened the rockers too much or there is something bent in there.

[Headhoncho]

1. Pull the valve cover and check your rocker arms or the bridge isn't broken.
2. Check height of the valve stem where it makes contact with the rocker arm that it's not worn down.
3. Spin pushrod to make sure it's not bent. May have to remove and roll across flat surface to tell.
4. If all above is good than rotate engine by hand and notice the amount of lift at the rocker arms compared to the adjacent cylinders. If less than others the cam/lifter could be shot.
5. If backfiring through the carb it could be a burned valve.
6. Check antifreeze and oil, could be blown head gasket into either area.
7. A lot of blow-by could be burned piston/rings or cracked rings.
8. Hope your dad's a TV repairman and that he has an "awesome set of tools" :p

Hope any of this helps.

JR