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Ok so I bought another LUV, 79' 4x4. Was told it needed a head gasket, turns out after further inspection the head was cracked. Not a huge deal, I've got an extra head off of my 79'. I've removed and installed several engines in these LUVS but never tore into one or any other motor for that matter. Didn't seem like it would be too difficult so I went for it. Everything went fine, no major hangups, untill I went to start it. It cranks, but no fire. almost sounds like it's free winding, or no compression. Anyone have any Ideas on what I might have done????? Thanks in advance.

Start with the basics. The Luv's engine is pretty simple, all things considered.

1. Is it getting fuel? Do you know you're getting gas to the carb and to the cylinders? Did you make any changes to the carb during the head swap?
2. Does it have compression? Simple test, and gauges are cheap. This can also tell you if you have the valve timing wrong.
3. Does it have spark?

If those three things check out, then you need to start looking at what could've changed during the head swap. Two of the most common mistakes people make are messing up the valve timing (not making sure everything is aligned correctly when you put together the timing chain assembly) and ignition timing (are you sure your distributor isn't off or turned 180 degrees from where it should be?).

Provided everything up there checks out, come back and we can help you further. However, I'd wager you've made a simple mistake during reassembly.

It is getting fuel. I tied the the timing chain to the gear with tie wire so it didn't move any teeth. When I went to bolt it to the cam I did have to turn the motor over a little to get the gear lined up with the cam. I did adjust the ignition timing but it didn't change anything. Valve timing makes sense. What guages do I need to buy? Thanks for your help

You'd need a compression gauge. They're about $30, but I'd bet that your local part store can rent one to you for a lot less. They screw into the spark plug hole and then you turn over the engine through a cycle on that cylinder and the gauge will hold the compression reading. This can tell you if your valves are closed when they should be....it's not 100%, especially if the valve timing is only off very slightly, but it can point you in the right direction.

I'd bet that you have the valve timing off a tooth or two. Grab a comp. gauge, run the test (10 minute job tops for all 4 cylinders), then go from there.

If everything is lined up like it's supposed to be, you shouldn't have to move the cam or crank at all to get the gears to bolt back on.

Also, double check your ignition timing. Rotate the engine to the TDC timing mark on the crank pulley and double check where your rotor is. I can't tell you how many times that I would have bet good money on something being put back together correctly (I was SURE), and it turns out I did something silly. Not saying that's the case here, but it's good to have your bases covered.

How do you correct valve timing, if that's the problem?

You'll have to take the timing cover off of the front of the engine, remove the timing chain, line up the timing marks, and reattach the chain.

It's absolutely critical that it's exactly right. You can't 'ballpark' valve timing and get the truck to run (albeit poorly) like you can carb settings, ignition timing, etc.

Ok so pretty sure I know where i messed up. When I put the new head on the cam wasn't lined up the same as the old one so I turned the crank to match it. I read a thread on her that said that if the crank is positioned at 0 and the cam mark was lined up then #4 should be in firing position. I've got it at zero and the cam is lined up. #4 is ready to fire so it looks like everything is good, iono, shoulda known better than to dig in on this.

There ya go. Line it up like it's supposed to be and you should be good to go.

Don't feel bad about messing up.....that's how you learn. The Luv's engine is a good place to learn...it's one step above a lawn mower in terms of simplicity.

I didn't change anything that's how it was the first time i checked it. Do I need to undo the cam from the chain and move the crank back to how it was? or should it be good to go and maybe I should start looking at something else?

Are you sure they're lined up? Are they lined up with tension on the chain? That engine needs to be at TDC on #4 with the marks lined up. One tooth off will mess you up.

What do you mean about it not being lined up before?

So it wasn't lined up when you took it apart? If that's the case and you're absolutely sure what the position of everything was, put it back that way. How far off are we talking?

I didn't know to line the crank and head up before I seperated them. The new head wasn't lined up like the one I took off it was just a couple teeth off so i turned the crank to make it line up.

Well, that's to be expected when swapping heads. You're positive it's lined up with tension on the chain? Did you run the compression check yet?

You know, another quick way to check this is to turn the engine until it's lined up like you're going to take apart the timing chain (#4 TDC). Then, once you're sure the bottom end of the engine is at TDC on #4, check your valves on the #4 cylinder. Are they completely closed? (ie - no pressure on the rocker arms)

Sounds like you have the cam timing right but its hard to tell without being there. You line up the timing mark on the crank pulley at 0, then the cam mark (behind the gear, a line on the camshaft) should line up with a mark on the head (its sorta on the rocker arm bracket, and is straight up and down anyway). #4 should have a tad bit of slack on both valves, and #1 will have tension on one of the valves. The distributor will be pointing at the #4 contact on the cap as well. If any one of these things is a bit out of whack, you need adjust the cam timing.

My guess is you have it right, if you tied the cam gear to the chain and didn't let it slip at all on the cam gear the whole time, even if you turned the crank a little it should still be lined up. My guess is that you need to check the valve clearance. This would be especially true if you swapped cams, rockers, or anything between the heads and did not readjust the valves afterward. It sounds like you took enough precaution with the timing, but your valves are adjusted too tight and not closing all the way. A compression test will help verify what is happening as well.

After several head swaps now, I now just remove the cam and rockers when swapping the head over. Then you can drop in the cam lined up exactly with the gear wired to the chain, and bolt the rockers back on over it. You have no valves hanging down to bump the head gasket or get bent on the pistons, and it is a lot easier to turn the cam to line up with the gear.

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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)

MEPR: Man, my 4x4 makes all other LUVs look good

Well now I've got it cranking good, just can't get it to fire. Replaced plugs, wires,cap,rotor,points,condenser,coil and ballast resistor. I didn't move the dist, so ignition timing shouldn't have changed. It's backfiring and popping so I think it's getting fuel, just no fire. Any Ideas?

This is a shot in the dark, but happened to me once on a truck I bought not running. Swap the plug wires at the cap with the ones directly across from them, so 1 for 4 and 2 for 3. It is possible to get the cam timing exactly 180 degrees off and have it look like everything is right. You can't put the disti in wrong, so swapping the plug wires will "correct" the spark timing in relation to the valve timing. With all the cam timing confusion just seems like its possible, even if pretty unlikely. Its an easy thing to check though. If it starts popping back thru the carb when you swap the wires, swap them back and look elsewhere.

The other thing is point gap can be really touchy. If you have that off it will pop and backfire but not run. Double double check the gap. Also I've gotten a couple of bad out of the box condensors, but they usually cause a no-fire problem.

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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)

MEPR: Man, my 4x4 makes all other LUVs look good

800xl if you were here I'd kiss you!! Not really, but I'm sure you understand. When I got the truck I took the cap off with the wires still attached. I thought something was up cause the #1spot had the longest wire and the #4 had the shortest. Now it all makes sense!!!!!! I switched them and it fired right up. holy freakin cow!

Lol, glad to hear you got it running. Its been a few months since I been around here, I'm just glad to see I'm not losing my touch. You gotta watch out for that 'dreaded prior owner' disorder. After owning several luvs, on a new one I pretty much look for anything that looks like it was taken apart and assume it has been screwed up.

_________________
95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)

MEPR: Man, my 4x4 makes all other LUVs look good

I hear ya there, this is my 6th one(pretty sure i've found my 7th) and at least once with all of them I've wanted to open a vein (fuel line) light a match and watch her burn. However I've always figured it out, well with the help of everyone here on a lot of it, and have yet to light one up.

I have one parts LUV that is a rusted out beat up wreck body-wise, it has gained several dents since I got it so that the LUV I was working on did not have to suffer.

_________________
95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)

MEPR: Man, my 4x4 makes all other LUVs look good