[alkon]

I am working on my 96 Sentra with a 1.6 liter engine. After changing the head gasket, I reinstalled the timing chain. I know that it is critical to have the chain timed to the cam and crank gears correctly. I even took pictures of the set up prior to breakdown and marked the chain and sprockets before removal. After putting the engine back together again, it failed to start. I have tried to do the logical things to see why the thing won't start (e.g., are there any electrical or vacuum connections that I forgot). After looking for quite some time, I determined that the problem has to be back with the timing chain.

Here are my questions:

1. When the engine is turned and returned to TDC, should the marks on the cam gears and chain return to their original positions? Mind did not return to their original positions. I am thinking that this is normal.... but I am not sure.

2. When I took the head out, several of the "caps" on the valve lifters fell out. I returned them to what I thought were their original positions. But I realize I may have made errors in where they were placed. Because of this, I checked the valve lash of all of the valves. All of them checked within specs except one exhaust valve. It read .022 inches; the specs show a maximum of .017 inches. How much of a problem with this excess in valve lash? Also, any suggestions on how I can get it back into specs?

Thanks for any assistance on this problem.

 

[I'm Slow]

this might sound stupid but i would make sure that the spark plugs are connected in the right order on the distrubutor because ive heard that the haynes manuel is wrong

 

[alkon]

Plugs and wires are in correct order

this might sound stupid but i would make sure that the spark plugs are connected in the right order on the distrubutor because ive heard that the haynes manuel is wrong

Thanks for your reply. I double checked the plugs and wires and they are in correct order.

 

[Kindfiend]

Here are my questions:

1. When the engine is turned and returned to TDC, should the marks on the cam gears and chain return to their original positions? Mind did not return to their original positions. I am thinking that this is normal.... but I am not sure.

2. When I took the head out, several of the "caps" on the valve lifters fell out. I returned them to what I thought were their original positions. But I realize I may have made errors in where they were placed. Because of this, I checked the valve lash of all of the valves. All of them checked within specs except one exhaust valve. It read .022 inches; the specs show a maximum of .017 inches. How much of a problem with this excess in valve lash? Also, any suggestions on how I can get it back into specs?

Thanks for any assistance on this problem.

I don't think one exhaust valve out of spec would cause those problems. The marks should line up on the chains and sprockets. If they aren't lining up the same as when you put them back in, it sounds like you missed a tooth. When I put my chains back doing the same job, the one of the marks was one link off and the car started and still runs fine. So, basically, I'm not sure what happened, but you may need to dive back in and see what went wrong.

 

[DaDusterDude]

I don't think the valve lash should be a problem unless it is really wrong. It would make quite a bit of noise, but it should still run. As a side, I haven't checked the lash on mine and it seems to be louder than I think it should. How did you check the lash? With these engines can you just stick the feeler gauge in while it is running and hang the valve and check for drag? Also do you know what they are supposed to be at. Once you get it running you might want to check again to make sure everything is still good because every setting I have ever seen is when everything is warm.

Is it even attempting to start? To check if your issue is electrical you can check to make sure you have spark. I suppose do the same for fuel. I'm too lazy to think real hard now about how many turns, but if everything did at one point line up then it should be able to line up again. Don't actually start the car but turn the engine over by hand a bunch of revolutions and you should see everything line up at one point. Any wierd noises or leaking from anywhere? If the head gasket was changed that could possibly be the problem too if for some reason it isn't sealing... How is the coolant level? Coolant real foamy and look like a milkshake? Can you have someone look for vacuum leaks while you try to start it?

 

[MagicPie]

Here are my questions:

1. When the engine is turned and returned to TDC, should the marks on the cam gears and chain return to their original positions? Mind did not return to their original positions. I am thinking that this is normal.... but I am not sure.

2. When I took the head out, several of the "caps" on the valve lifters fell out. I returned them to what I thought were their original positions. But I realize I may have made errors in where they were placed. Because of this, I checked the valve lash of all of the valves. All of them checked within specs except one exhaust valve. It read .022 inches; the specs show a maximum of .017 inches. How much of a problem with this excess in valve lash? Also, any suggestions on how I can get it back into specs?

Thanks for any assistance on this problem.

1: after you turn the engine to TDC the marks will not line up again for many many turns so this is normal

2: Dont think this is a problem

the engine likely lacks compression take out the fuse for the fuel pump and try cranking the engine this will allow oil to cirruclate and get on the cylinder walls therfore making compression then replace the fuse it should start up after a few tries

 

[alkon]

Another question

My question about the timing chain came as a result of changing my head gasket. Here is another related question: When changing the head gasket should I have used a sealant to fix the gasket to the head? I read in another post of an individual recommending this. I didn't think it was necessary as I was able to place the gasket correctly on the head without use of an adherent.

 

[cwruck05]

I am working on my 96 Sentra with a 1.6 liter engine. After changing the head gasket, I reinstalled the timing chain. I know that it is critical to have the chain timed to the cam and crank gears correctly. I even took pictures of the set up prior to breakdown and marked the chain and sprockets before removal. After putting the engine back together again, it failed to start. I have tried to do the logical things to see why the thing won't start (e.g., are there any electrical or vacuum connections that I forgot). After looking for quite some time, I determined that the problem has to be back with the timing chain.

Here are my questions:

1. When the engine is turned and returned to TDC, should the marks on the cam gears and chain return to their original positions? Mind did not return to their original positions. I am thinking that this is normal.... but I am not sure.

2. When I took the head out, several of the "caps" on the valve lifters fell out. I returned them to what I thought were their original positions. But I realize I may have made errors in where they were placed. Because of this, I checked the valve lash of all of the valves. All of them checked within specs except one exhaust valve. It read .022 inches; the specs show a maximum of .017 inches. How much of a problem with this excess in valve lash? Also, any suggestions on how I can get it back into specs?

Thanks for any assistance on this problem.

No question is a dumb question. No answer is a dumb answer.

 

[Kindfiend]

My question about the timing chain came as a result of changing my head gasket. Here is another related question: When changing the head gasket should I have used a sealant to fix the gasket to the head? I read in another post of an individual recommending this. I didn't think it was necessary as I was able to place the gasket correctly on the head without use of an adherent.

I didn't use it since the gasket has sealant on it already. Just make sure the head is seated correctly by torqing the head bolts, loosening them, and tightening them again.

 

[wes]

As stated the marks will not align unless you get the correct number of turns just right. You can count the links between the marks to make sure they are correct. If you were way off you'd hear NASTY sounds when trying to crank it over. Did you possibly flip flop the hoses going too/from the fuel rail? And unplug and reconnect all harness connections.

You SHOULD NOT use any type of gasket sealer, just make sure the head and block are flat and that they were clean. Ideally you want to use a torque angle meter rather than a torque wrench and folow the FSM specs to the T.

 

[fritzfry]

my exhaust cam was a roller off and it wouldn't start. when i realigned the chain it started right up.