apollotrance1

I have started back at the beginning. I did a compression check and it came back at 75, 25, 25, 45, 45, 90. Could the timing be that bad to throw off the compression that bad? I am beginning to think that the previous owner messed with the cam and gears and set them incorrectly.

DFlintstone

Of course any effect of ignition timing on compression would be minimized with the plugs out. But seriously, sure. The intake valve needs to open right for the cylinder to "take a gulp", and the exhaust needs to close right to compress it.

But in post #1 you said it had been running. I would say those numbers are in the "it might run, but why bother, range. Are you familiar with a spark plug "anti-fouler"? It's a little extension, screws into the plug hole, then you screw the plug into it. If you had, say, one really bad valve guide or one cyl that was oil fouling your plug, you can use one of those and it might actually keep the plug firing well enough to make that cylinder useful.

I wonder if the PO didn't intentionally install those short plugs with the idea that having them recessed, so they might duplicate the action of an anit-foulers.

I'm going to guess you never saw it run, and if you had there would have been allot of blue smoke. I guess there is a chance though that carbon that fell in the cyls. when you changed to the proper plugs is preventing things from sealing. (an I mentioned before).

I'd probably go ahead and pull the head. Doubt I'd even bother with a "wet" test. (the two 25's together suggest a head gasket problem ALSO). How many miles?

To see if the chain slipped you can check the "crossover" of the rockers, after you pull the valve cover. At TDC the exhaust should be closing as the intake is opening. I'm not sure that test is "dead nuts" on, but the timing mark should be darn close to tdc when they are balanced. (you can also feel with a straw or something in the cyl to verify that that the tdc mark on the balancer is correct).

Sorry btw. I'm at 263K, heading toward those #'s myself.

apollotrance1

I am familiar with a anti-fouler. Even after I pulled the original plugs there was no oil on it, as well as the new plugs I put in after cranking it over and over as I tested the engine.
The truck ran, and I even drove it, so your guess is wrong. There was NO smoke at all, and I even did the tested the rings by dropping a tad bit of oil directly in the spark plug tunnel into the cylinder. I checked the chain by taking off the valve cover and turning the balancer and the valves were opening and closing properly as it hit TDC. I even went backwards a tad bit to check the slack in the chain, and the valves moved immediately.

DFlintstone

Hey Fantastic! Very glad to be off the mark. So those 25's being together sounds like the head gasket. You wrote, "I even did the tested the rings by dropping a tad bit of oil directly in the spark plug tunnel into the cylinder. " Guess that's called a "wet" test. I suppose since there is hope that the lower end is OK I WOULD do the wet test as well. The more info the better when you pull the head. Just to be through, since you have the cover off I'd check two rockers, (on 1 or 6), and verify the mark on the balancer. It's only a matter of turning a bolt. (e-fan comes right out to get room for the wrench)

(btw, for the wet test I find a length of small vinyl tube is handy to blow a couple tablespoons of oil in the hole)

apollotrance1

When the cover was off before, I set the balancer to TDC by the marks, and the valves on #1 were closed. I a continued to turn it, they started to open. I will be pulling off the head tomorrow after I get out of class. I dont remember seeing it, but are the bolts holding the head to the block use a special socket? I remember someone mentioning they needed spline sockets to get it off, but I dont recall seeing that kind of bolt head.

DFlintstone

Maybe someone who's done a 4.0 can chime in. As far as I know you will just need a deep well for the ones with studs. I think mine are all regular hex.

You might want to hit the manifold bolts with some pb ahead of time. Especially where the exhaust ones hit the head, and the nuts holding the pipe.

DFlintstone

The "crossover" of the rockers, would be checked at the top of the exhaust stroke. (as exhaust closes, and intake is opening). Of course one or six will be at tdc on compression while the other is on exhaust. Once I put a straight-edge across the rockers, then turned the engine back and forth via the crank pulley bolt.
The "6 million $ question" would be, is that right on TDC for a 4.0. Maybe someone here more familiar with the valve timing would know.

apollotrance1

As far as I know, I think the lifters are bad. After I pulled the head, I check the valves. All looked to be how it should be. I am going to clean out these lifters and change the oil.

DFlintstone

A really good look at the gasket, (and surfaces), especially between 2 & 3. Would be next. With 25 lbs in those two there is almost certainly something going on there. Wire brush /wheel the head, suspect areas. Rag & solvent. I would use killer light and magnification to look for cracks.What I do is set the head just right and put Kerosene, (or diesel, or cleaning solvent), Into the ports. A bit messy, a big tray, old tub or shower pan would be handy. Without spilling it on the piston side, you put it in the port and see how it leaks past the valves. A good one will just soak/wetten out around the edge of the valve. Course if it's dripping or running through it's done. Also you can get an idea of warpage with a regular straight edge,(level/framing square) and a feeler gauge. There is a spec somewhere but of course flat is the goal, .035--.040 would be pretty not flat. You go both long ways and side to side.

If I had two 25's with a wet test I might just take my head to the shop, ask them to look it over. Or If it held kerosene well, I saw no cracks, and it was better than .035 I might just stick a new gasket on it and give it a go! (but I'm shamefully cheap).

apollotrance1

I did the liquid test for the valves and nothing ran through. The gasket looked good between 2and 3 with no cracks in the head at all. I think the lifters were leaving the valves open to get bad compression. I have cleaned out all the lifters and will be putting them back in within the next day or 2.

DFlintstone

Great! What did you use?

apollotrance1

Mineral spirits for the leak test

DFlintstone

Sounds good. A little weeping/soaking out is expected. If you smear oil, thicker the better, 90w or stp ect, on the cylinder walls you can turn the crank via the bolt to move a piston up then down. This can help get any particles up out of the space between the top of the piston ind the top ring. You might wipe that with a clean paper towel and look for sign's of that carbon from your plug holes.

Also feel for the "ring ridge". near the top of the cylinder there the rings stop moving up. Not great if you can catch your fingernail in it. Also look real good at the cylinder walls for bad spots, scoring/cracks.

I would still lean toward a head/head gasket issue, would be new to me for lifters to be responsible for your readings. I would look into the specs for worpage/flatness. Maybe somebody else here can help. Wonder what a shop would charge to check it out. Also new valve stem seals....I would do that myself, I think you can rent a spring compressor, Also with the valves out you can examine it better.

apollotrance1

Bout to head home and drop in these lifters and see what happens. I would take this head to a machine shop and get done up but it is a renix. I am now in the process of "gathering" stroker parts for my Jeep. So is it even worth dropping in new lifters??? I heard that valve seals should be replaced, but there is no oil in the cylinders.

DFlintstone

When they get worn out it will normally smoke. One sign is if it smokes when you first start, because when you parked it hot, oil ran down.

It's up to you..I didn't price them but I suspect they might be cheap. 1/2 the time I have them because they come in the head gasket set. Not a big deal to change them and with the valves out you can inspect the head better. Also if it's not flat and you need to surface it you need the valves out to properly clean it after.

It's been a while, I think you can test a lifter by putting it upright in oil and working it with a dowel or something. Should pump up hard.

Found this an cleaning lifters. Not sure out of what.

http://www.dsmtuners.com/forums/arti...s-cleaning.htm