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1980 luv. Stock motor that I had professionally rebuilt. I removed and installed the motor for the rebuild. The motor won't start just pops and backfires out of the carb. Tried switching plug wires. Nothing. Seems to be getting spark as I pulled each plug wire and checked while cranking.
Took off the cam cover to check timing marks and noticed the time chain is not aligned with the mark on the sprocket see pic


Is this my problem? Don't know where to go from here...

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1980 Longbox Luv, rebuilt 1.8l, smog delete, weber carb, electronic ignition.

As long as the chain has the correct number of links between the crank gear setting mark and the cam gear setting mark when the engine is at #4 TDC it should be fine, the gear marks don't have to align with the chain setting links. The problem is you can't count links without removing the front timing cover.
Remove the plugs so you can rotate the engine by hand, then see if it will get to #4 TDC: crank timing mark at zero degrees, cam gear alignment dowel straight up, distributor rotor pointing to #4 plug terminal in the cap. If you can't get to all these conditions report back what won't align. If it gets close rotate the engine two complete revolutions & see if the cam returns to the exact same spot every time with the crank at zero degrees. If you can get the engine to #4 TDC & it returns to #4 TDC after exactly two complete revolutions the chain should have the correct number of links between the two setting marks.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

Ok here is what I got. Motor with #4 TDC. Pics showing cam allignment, distributor, and crank pulley timing marks.

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1980 Longbox Luv, rebuilt 1.8l, smog delete, weber carb, electronic ignition.

Looks like my distributed is off. Does that mean my oil pump is in wrong?

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1980 Longbox Luv, rebuilt 1.8l, smog delete, weber carb, electronic ignition.

1st pic- Looks like the setting mark on the cam & front rocker bracket align, if so this puts the cam in position for #4 TDC on the compression stroke;
2nd pic- Rotor is pointing to #1, not #4, so #1 plug will fire, but #1 combustion chamber has a partially open exhaust valve due to the cam position;
3rd pic- Crank timing mark is about 6 degrees before, not 0 degrees, so pistons 1 & 4 are not quite at the top of the stroke;
so your engine is NOT at #4 TDC since all three of the conditions I gave you previously are not met.
It appears the mechanic installed the cam 180 degrees out, or timed it to #1, not #4 as it should have been. This is a common mistake for those not familiar with Isuzu's #4 timing requirement. The usual fix is to swap the #1 & #4 and the #2 & #3 plug wires on one end to make the cam timing & ignition timing agree, then make a note of the change so that it doesn't get changed back. If you haven't already tried this wire swap it may allow the engine to start, but hold off until you do something else first.
I am concerned that the crank is not at 0 degrees when the cam is at #4 TDC, so you need to check to see if the timing chain is off one or more teeth. Do this: First rotate the engine the little bit to where the crank timing marks aligns with 0 degrees, the rotor should still point MOL to #1, take a pic of the cam position, best if from the front of the cam gear showing the gear alignment dowel- ideally it should be straight up and the cam and rocker bracket setting marks should still align. Next rotate the engine one full revolution until the crank mark again aligns at 0 degrees. The rotor should now be pointing to #4. Now take a another picture of the front of the cam gear showing the position of the alignment dowel. With the crank at 0 degrees the cam gear dowel (and the cam setting mark)should be straight up or straight down, if it's pointing to one side of straight up or straight down the chain is likely off one or more teeth.
If the cam gear dowel is straight up or straight down when the crank is at 0 degrees the chain is good, you can swap the plug wires, the engine should start. Make sure the valves are adjusted properly first.
If the cam gear dowel is pointing off from straight up or straight down when the crank gear is at 0 degrees your chain is off & needs to be corrected, contact the mechanic that installed everything incorrectly and see what he intends to do to fix it. Pulling the cam gear off, then rotating & resetting the chain the number of teeth it looks to be off might fix things to the point the engine will start with the plug wires swapped, but the cam will still be 180 degrees out & you don't know for sure the crank gear was indexed properly with the chain.
To fix it right first back off the valve adjusters or the rocker arm brackets so that all the valves are closed (this is so you can rotate the crank without the chance of a piston hitting a valve & can rotate the cam free of spring tension), then rotate the crank to 0 degrees so that the rotor is pointing to #4- this puts both the crank and ignition timing to #4 TDC. Next remove the front timing cover, cam gear and chain, then spin the loose cam until the setting marks align- this puts the cam timing at #4 TDC. Now reinstall the chain, indexing the crank gear and cam gear setting marks with the chain setting links- this puts the proper number of links between the crank and cam setting marks-, install the cam gear with the chain attached, this synchs the crank, cam & ignition to #4 TDC. Install the timing cover, release the tensioner, adjust the valves. With the plug wires back to the original position the engine should start.
The oil pan may have to drop to R&R timing cover, so I don't know if this work can be done with the engine in the truck.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

Crank at o degres the cam alignment Mark doesn't match up

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1980 Longbox Luv, rebuilt 1.8l, smog delete, weber carb, electronic ignition.

Went on full revolution. Rotor pointing at #4, her is a pic of cam gear sorry hard to get a good shot. It is not exactly strait up and down but pretty close.


I really appreciate the help. This is the reason I took it to a "professional" to begin with to avoid these problems...

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1980 Longbox Luv, rebuilt 1.8l, smog delete, weber carb, electronic ignition.

Try swapping the 1&4 and the 2&3 plug wires and retarding the dizzy as you crank it, it just may start no more than the chain is off. Whether you can get it to run well enough to suit you with the chain off that much is another story. The cam is definitely out 180 degrees and the chain is off at least one tooth, possibly more, which I think advances the cam too much by the direction it appears to be off, it may be off so much it just won't run right even if you correct the advance enough by retarding the dizzy to get it to start. I would inform the engine builder it's not together correctly, then if you can't get it to run let him fix it right.
If you haven't adjusted the valves do so before trying to start it.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

I really appreciate you taking the time to help. Will give it a shot by switching the plug wires.

Thank you.

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1980 Longbox Luv, rebuilt 1.8l, smog delete, weber carb, electronic ignition.

http://www.ebay.com/itm/1980-Chevrolet- ... 62&vxp=mtr
Buy this, it's a very good price.
It will repay it's cost many times over.
It will have everything I have been telling you along with pictures, you can even show your mechanic what he got wrong & how he did it.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

I got it it running!!! Thanks to you oldestisuzuist. I can't thank you enough. I owe you a few beers for

sure. It actually run pretty good but had to retard the timing quite a bit, it idle along nicely for about 20

mins or so. Sounds like a slight miss on the exhaust side of things. I will be talking with the guy who

rebuilt it for sure.

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1980 Longbox Luv, rebuilt 1.8l, smog delete, weber carb, electronic ignition.

If you decide to go ahead and use it with the cam advanced because of the chain being off you probably can't use a timing light to set the distributor advance, you'll probably have to just do it by ear- advance until it starts to ping, then back it off until it doesn't plus just tiny a bit more.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

Cranny....I don't know about the '80 engines but I have 'moved' the timing chain around the gears several times when I messed up and installed it wrong. It may be that you would want to re-align yours to get the timing marks etc. in agreement. On my '77, I rotated the engine until the master link appears up at the very top. If your present alignment allows it, get the crankshaft up to TDC first---you may have to rotate the engine several times to get the #1 piston up First, attach some wire through the chain links (both sides) a little below the cam gear so that you can be sure the chain does not fall down into the timing chain chase. Next, use a slender bar or a long screwdriver to push the chain tensioner towards the passenger side of the engine. There is an adjustment screw there that allows the chain to be tightened or loosened. Turn the nylon screw one way and the chain is tight , turn it the other way and it is loose. There is just enough play in the loose chain to accomplish the fix. Then remove the master link pin keeping the chain attached and wrapped around the cam gear. I have even put an old T-shirt rag on both sides of the chain down in the chase area to keep from losing the chain ends. Then you can raise the links on one or both sides with the wires to allow the cam to move left or right one link at a time. Then you can adjust the cam position if you need to. With the #1 at TDC, you can rotate the cam shaft with a pair of locked on vise-grips to where it is supposed to be according to the cam gear stamped marks. Or once you get the finesse of this, you can understand how to 'rotate' the chain around the crankshaft gear below if needed. By keeping enough slack in the chain to barely allow this movement you can re-center the alignment marks and get everything in place again. Also, with the wires and the t-shirt in place, and the chain not dissembled, I have even removed the cam gear from the camshaft completely. This will let you get the cam rotated around to the proper place a lot quicker. It takes a little prying to get the gear back on the shaft but it is faster. It works on my '77LUV and my '74 LUV/Toyota. The '74 has a 20-R engine in it. Good luck and don't be timid......

Appreciate that don, will give this a shot when I get a chance

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1980 Longbox Luv, rebuilt 1.8l, smog delete, weber carb, electronic ignition.

Remember this is an interference engine, if you rotate the cam & crank independently with any tension at all on the valve adjusters the piston may hit a valve.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.