jlawley97 Posted August 2, 2019 Report Share Posted August 2, 2019 So I have a 1989 z24i and I was driving along and then it just died and like I heard metallic sound. I tried to pop the clutch and start it again and it just like backfired a few times and went out again. I checked if the chain was snapped then tried to start it again and it wouldnt start back up, except every once and a while an extremely loud pop. The chain seems fine and the valves look ok. Some people said it might be timing but that is spot on too. One thing that i did notice is that when i was at top dead center for cylinder one like the one where the distributor pointing to spark plug one the lobes are up as if it were the exhaust stroke which made me wonder how it was ever running in the first place. so i spun the distributor around and now it runs, awfully, but it runs for a second. I have no idea what is going on here. For reference this is what I used to make sure everything is in line and correct http://www.infamousnissan.com/forum/showthread.php?t=26853 it just doesnt make sense that the cylinder 1 would be sparking when the exhaust valve is opened. So thats why spun around the distributor. And the way I see it there is no possible way for me to have jumped the timing in a way where everything lines up(like in the above post) AND the timing be EXACTLY 180 degrees off. I am so confused to be honest I know i am kind of all over the place so if someone could just walk me through how i am supposed to have everything lined up. this is it at top dead center and the distributor sparking cylinder one 1 Quote Link to comment
datzenmike Posted August 3, 2019 Report Share Posted August 3, 2019 There are 2 TDC on a 4 stroke engine. The one you want is the compression stroke on #1 piston. The front most lobe (exhaust) should be around 8 o'clock as viewed from the front and the second lobe (intake) at about 4 o'clock. Give or take. Both should be pointing down not up. If yours are generally pointing up at 10 and 2 then you are on the exhaust stroke. You can't spin the distributor around without taking the oil pump and drive spindle out and turning it and putting back in. You can loosen and turn slightly to set the timing*. The rotor on the distributor has TWO pointers. At TDC the top one intake plugs, should be pointing generally at 9 o'clock as viewed from the left fender looking in. The other abut 4 o'clock for the exhaust plugs. The rotor should be #1 intake at 9 and the #1 exhaust at 4. Check that ALL your wires go to the correct plug. They alternate intake , exhaust, intake.... *You probably just messed with the timing this is why it still sort of runs. You'll need to reset with a timing light and learn not to make random adjustments. 1 Quote Link to comment
jlawley97 Posted August 3, 2019 Author Report Share Posted August 3, 2019 The problem is that it was running and driving absolutely fine before and i set the correct timing on it with a timing light than just stopped. The timing hasnt changed whatsoever so like how was it even running before? thats what I dont get because the way i set it up is that the crankshaft is at 0 and the camshaft set like how i have it in the above, then the distributor half moon is like how it is below so the distributor is pointing at the I1 and E1 1 Quote Link to comment
jlawley97 Posted August 3, 2019 Author Report Share Posted August 3, 2019 something even weirder i just noticed that on camshaft the one in the picture. When that peg is pointing up so are the cam lobes for cylinder one I have another head laying around and when its peg is pointing up the lobes for cylinder one are pointing down this is so weird. 1 Quote Link to comment
datzenmike Posted August 3, 2019 Report Share Posted August 3, 2019 3 hours ago, jlawley97 said: The problem is that it was running and driving absolutely fine before and i set the correct timing on it with a timing light than just stopped. The timing hasnt changed whatsoever so like how was it even running before? thats what I dont get because the way i set it up is that the crankshaft is at 0 and the camshaft set like how i have it in the above, then the distributor half moon is like how it is below so the distributor is pointing at the I1 and E1 If at TDC, drive spindle like above, cam lobes up and rotor pointing to E1 and I1 it can't run. If the lobes are up, you are firing a cylinder during the cam over lap position, basically just starting the exhaust stroke. So you are mistaken or not describing it properly. 1 Quote Link to comment
jlawley97 Posted August 3, 2019 Author Report Share Posted August 3, 2019 are there different cams for the z24 and the z24i? because there does not seem to be when i look it up but then how does my cam shaft have the peg up and the lobes up when everyother one is the peg up and the lobes are down(for cylinder one). I know what to do at this point, just crank it 180 degrees and then redo the oil pump but i just want to know about the cam shaft now like if you refer to 2 photos above that show the camshaft sprocket and then lobes being up on cylinder one that is what i am referring to. couuld the cam shaft have broken? because i see no other way that this could happen 1 Quote Link to comment
datzenmike Posted August 3, 2019 Report Share Posted August 3, 2019 The Z series cams are all the same. There are 2 TDC positions. One with the cam lobes UP and one with the lobes DOWN. You want the compression stroke where the lobes are down and valves closed. Take the #1 exhaust plug out and push a plug of Kleenex in the hole. Turn the engine with a large wrench. When the Kleenex pops out you are on the compression stroke. Find the timing scale behind the pulley near the alternator and set to TDC with the timing scale at 0. Check that the front two cam lobes are pointing downward and both valves are closed. This is the beginning of the firing stroke so the rotor should be pointing at or near the #1 intake and exhaust plug wires on the cap. Generally to 9 and 4 when you look from the driver's side fender. Do you have this????? 1 Quote Link to comment
jlawley97 Posted August 3, 2019 Author Report Share Posted August 3, 2019 no i understand all this. There is something weird going on, Ill take pictures of the cams to show you what is going on. 1 Quote Link to comment
jlawley97 Posted August 18, 2019 Author Report Share Posted August 18, 2019 Okay I am finally back and found out the issue. That little peg on the cam shaft had come out. is there anyway to make sure that never happens again ?? Quote Link to comment
datzenmike Posted August 18, 2019 Report Share Posted August 18, 2019 Use a large washer to cover it. Tighten bolt to 90-120 ft lbs. 1 Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.