For all the regular posters u might remember me as the dunce who got called the oil pressure gauge a water temp gauge and as the guy who never really learned to use the search. Anyways im back to bother you n my absence was due to the fact that may car got totaled in nov and i finally got a replacement last month. The new car needs some tlc and the one of the heads had a busted valve. The guy I bought it from had the engine striped down to the block and although all the stuff came with the car ($1000) I decided to just rebuild it using my engine. The reason I just didnt drop my engine in was because mine got hit in the accident and took some damage. So anyway the exhaust cam on the left head got busted and i had to change it along with the sprocket. I cant remember if i fully rotated it while the head was off or not but now that its back on the block it wont turn past 2 stokes in either direction . It sounds as if someting is hitting when i try to turn it. I checked the pistons to see if any were in the way but all looked to be backed off enough. I would hate to have to break down everything again or to try and start it and break something. So any ideas?

P.S. my new baby is straight from japan baby. Thought that was PRETTY COOL

 

I found your problem....


Is the head bolted to the block while you're trying to turn the cam? I suspect yes, but then how do you know the cylinder position to say that the cylinder isn't interfering (this is an interference engine, in case you didn't know).

Honestly, and don't take this the wrong way, I get the impression that you should be sending this engine to a machine shop to be assembled.

 

if any of the pistons are at the top of the compression stroke, that is the problem. if you tried to turn it too hard, you probably already bent a valve. if you are POSITIVE that it's not a piston, then it's probably accident damage or a siezed up lifter. it sounds like you are using the head from your car with the new camshaft from the other car... if the head you are using had the cam broken inside it, then the head is obviously not likely to be good.

i'm thinking of a bunch of possible problems. also, you can't use those used cams from one engine with the used lifters from the other. or at least, it's highly discouraged

 

Yea it is a cam from one engine with a head from another. I looked through the spark plug holes if you were wondering how i checked for piston clearance by the way. But maybe one of them was to close after all. I tried to start it today after it was all wired up and everything. Rolled over but bla.. so close but no cigar. Nothing sounded to be hittting thank goodness or any problomatic noises. Though when I was turning the ignition I saw a light on the dash that was new to me. It may only be on the JSPEC cars but it was an horizontal oval with horizontal lines coming from both sides and vertical waves coming from the top of it. Anyone hav a clue what that means? Also when I turned off the ignition and took out the key the yellow lights on the side fenders were blinking for a few seconds. Like an emergency signal would. Does anyone no what that means or if its normal for a JSPEC car? Also if one of my headers isnt fully fastened on would that cause a car not to start even if everything else was in order?

P.S. Im flat broke and just trying to do my best to live the dream again with some guidance from the blunt zx service manual aka the bible. So please bear with me.

 

By the way the cam that was broken was only busted at the end where the cam gear bolts on and that was due to the cam gear being hit getting broken thus enough to crack the end of the cam shaft.

 

A non-fastened header would definately cause starting issues, but I think you have deeper problems with your car. I'll ask questions in the morning when my mind is clear and active.

 

you have a LOT of connections that could cause your no start problem. i hope you got the firing order right. but also, could be a much bigger problem, i agree.
but start off checking for spark, then fuel (this considering that you are confident that you got all the mechanical aspects right. like timing the cams). also, when i had my car that far apart, it took quite a bit of cranking to get it started. then it ran great. you may just need to crank a bit more, although, within reason.

dunno about all your lights. good luck with that

 

I appreciate any advice you guys have to give. Im pretty confident about my mechanic skills even though Ive never done something this in depth im not a noob to it. When putting everything together I took my time and rechecked everything repeatedly and checked the SM as well to make sure. The wiring im sure is all good seeing that again I used the service manual and even another car for reference. I'll admit it was late and I had borrowed a battery from someone briefly to try and start the car so I think I only cranked it about 5 times. I do plan to run a full check up on if its even firing and if its getting fuel just I was hoping for somewhat of a blessing I guess with a first try start. Still like you guys said there are alot of variables so its more assuring to ask opinions. Hey willkrom1990 when you had your engine put back together was there anything that you had to deal with before u got it started? And Im a get that header straighted out asap as well. Also im fairly knowledgeable with the spark plug and fuel system seeing that my car had once broken down due to a short in a wire and I spent 3 days going over every last possible thing why it wouldn't start before it turned out that the last wire I checked after checking every other singe one in the system was burnt out .

 

So it cranks but will not start?

1. Compression test. If the values aren't above 100, you have a serious problem. If they're not above 120 or so, you need to do some work anyway (could be a smashed headgasket, worn rings, etc). They should be higher, but 120 is acceptable, for the most part. Note: Even 75psi will still fire, but will have excessive blowby and will not fire under heavy loads (I know this from experience). This test is more for the purpose of making sure that you have the timing done right, because if it's not, you won't get any considerable compression (valves would be at least partially open on the compression stroke if this is why it won't start).

2. Fuel pressure test. Come to think of it, check to be sure your fuel lines are routed properly (I made this mistake when I was putting an engine back in once). The feed and return lines on the driver's side of the engine should NOT cross each other between where they enter the engine bay and where they connect to the rail. i.e. The front-most fuel line (which comes out of the fuel filter, I believe) connects to the front-most fuel connection. If you have them crossed, then your engine won't get any fuel because the feed line will be blocked by the pressure regulator (which only allows a one-way flow of fuel). If that's fine, get an in-line pressure gauge and search for one of my writeups on how to test the fuel pressure. It could be the case that your fuel pump control unit died. They are problematic on early Z's, and I've had one of these die on me out of nowhere.

I doubt it's a spark issue, but I'll recommend cleaning your PTU connections and CAS connections anyway.

 

what problems did i have when i first tried to start it?
i made a noob mistake that i'll never make again. on this car, you DO NEED the tubes coming from the air cleaners connected to the manifold to let it run. those vacum lines coming off of them are very important. this was my only hold up when starting the car for the first time after the head swap.
there arn't many other simple things like that that i can think of.

just test the compression, spark, fuel pressure, and fuel getting into the cylinders. one or more of those elements is obviously not present.

"Im pretty confident about my mechanic skills even though Ive never done something this in depth im not a noob to it. "

i wasn't doubting your skills. its always possible to make a mistake. often those with the greatest skills go too fast and forget something!

 

Well I was just putting that out there. Its good to have someone who is comfortable at watever it is there doing then some dunce who is just totally lost. Im a try n get the tool to do a compression test. hopefully they sell them at the store cuz i wanted one of my own anyway. I havent had the time to investigate anything as yet to give you guys feedback since ive been busy with work n my evenings have gone to stripping my wrecked car (landlord doesnt want all these cars laying around his place ). But my two lovely days off are almost hear n ill have all the time i need. Thanks again for all the advice

 

Oh I almost forgot to mention. I removed my EGR, PRVR, and AVI ****. Or should I say I just didnt add it. I thought about it when u mentioned the lines comin from the air intake tubes. I set everything up (bypassing) as everyone says so on the forums. Just one thing was that for the EGR selenoid valve the line that goes to that from the air intake I bypassed to the outlet on the throttle body that one of the other egr selenoid vaccume lines ran to. Dont no if thats ok or not but i didnt think it would effect starting.

 

Misrouted vacuum lines won't cause a Z to not start. I've started my Z with an intake hose off completely... small air leaks won't do it.

Compression gauges are available at Pep Boys, Auto Zone, Advance Auto Parts, and probably Sears and Home Depot even.

 

It should be pretty obvious I guess since your talking about checking for spark but wat exactly does PTU and CAS stand for?

 

power transistor unit
crank angle sensor

 

DUH I should wack myself for not guessing that right off the bat.

 

i obviously wouldn't ever say that you were wrong, but this has been my experience: when i cranked the engine with the intake hoses disconected, it would barely fire for just a few seconds and then cut right off. so, in a sense, your statement agrees with my experience, because it did start in some manner, but as soon as i put the hoses on, it ran perfectly. i really wouldn't say that it was "running" for me when i had the hoses off, and that is the ONLY thing that changed between when it didn't run and when it did.

my conclusion from the total of the write-ups that i've read has been that the EGR does more good then bad, so for most street cars it is preffered to leave it on. but i have read other write-ups that say differently, but the ones that said to leave it on sounded more convincing

 

Sorry I took so long to get back to you guys. I didnt have much time to diagnose the car and my net is out so im on a friends computer. Well to my amazment the exact same wire that had shorted out on my last car was causing this one not to fire. So now its sparking up and it sounds like she is ready to roar. But as i was giving it a few crank test (before I got it firing) I noticed the timing belt started slipping bit by bit. I inspected the blet before I put it on and its fine. I almost had a heart attack and thought that the exhuast cam that I couldnt get to fully rotate was still stuck and the belt was slipping over it. But I looked at all of the cam gears and they where all rotating freely. Im just hoping that the little the belt moved didnt cause me to ben my valves while I was cranking the engine. I dont no of any adjustable tension for the timing belt except the one that alows you to get it on and then it expands on its own accord to tighen the belt. maybe it sliped because there was so much strain on it while it wasnt firing. I have no clue. Some help here guys?

 

Not really true, actually. A malfunctioning EGR (which is common at the age of these cars) or an improperly set up EGR (i.e. one with misrouted vacuum lines - very common on Z's that have been worked on extensively) will potentially cause catostrophic damage. Unless your state does visual inspections, there is no reason not to remove the EGR - the car will pass emissions without it and it cannot do any harm if it's not on the car.

And I'd like to see what writeups you're reading that recommend leaving it... all the reputable ones I've seen (from people like Ash, for example) recommend removing it because of the risk involved in leaving a poorly functioning EGR valve on the car. I suspect the ones you're reading are from people I'd flat out ignore.

http://www.twinturbo.net/net/viewmsg...&msg_id=967920


cake872 - reinstall the timing belt and tensioner, try again. Let us know if it slips. It could've just been a fluke from something being installed slightly wrong. If it still does it, we know there's a bigger problem. Obviously, don't keep cranking it if the belt slips again, we don't want to bend any valves.

 

zdriver: well that is believeable. thanks for the clarification. the write ups that i read focussed on the fact that the EGR helped keep the firing chamber temperature down. but maybe i will think about doing away with mine when i put the new exhuast on (if it even gets done). i'll post or PM you the link to the main write up that i was going by if i come over it again, but i really don't remember where it was. i think somewhere on zcar.com, but several months ago.

cake: don't forget to get the tensioner to 4 mm and turn then engine twice then check it again. it CAN change after turning it, because of the un-even distribution of tension on the belt. it happened to me. so you may have to do it several times

 

The EGR's purpose is to keep cylinder temps down, but the difference is minimal and does not outweigh the risk of a malfunction. Not having the EGR will not cause excessive cylinder temps.

 

good stuff. thanks for the info.

 

your main source of temps is your cooling system (both radiator and oil) proper oil flow, and proper A/F mixture.

 

fo' sho'. i just read this write up that made it sound really important. i understand.

 

Does anyone no the socket size for the crank pully bolt?