crxaddikt

my timing belt on my ZC DOHC snapped lastnight on my way home from work, my car is a 90 CRX Si (no mods, just stock), i was driving on the highway going probably 60 mph about, in 5th gear, then the engine slowly stuttered or stumbled a little and then started gradually dropping in speed, and felt exactly the same as when you start running out of gas while going highway speed, . . . i pressed the gas but was'nt gaining any speed, so i just started to veer off towards the nearest exit, putting the hazard lights on and just coming to a stop on the shoulder of the exit lane.

i knew i did'nt run out of gas, cause the tank was 3/4 full,

so after stopping and turning the car off, i tried to start it a couple times, and it sounded like a stuttering starter trying to crank, but not turning over, and i tried a couple times and it was'nt starting, and there was a battery and an oil light on the dash also. i looked under the hood, wiggled some connections etc . . ., then tried to start but still did'nt start, so i called mechanic friend and he came & met me to check it out, he took the timing belt cover off and saw that it was a snapped timing belt ! !

i was shocked, cause i did'nt expect it to happen just yet, but i also knew i should of done it earlier, and now i was only concerned whether it damaged anything internally or not ??? one thing i felt better about was the fact that it did'nt make any type of noise or sound when it happened, cause seems like if a valve or rod were bent that it would make some sort of sound ???, cause all it sounded like was a regular smooth engine running, and slowly declining in speed as if it ran out of gas or was stalling and just had a little stumbling to it, just like running out of gas, but no knocking or metal noises or anything.

i never knew exactly what mileage was on the ZC motor since it was a used imported motor, so i had to just make a guess, using that as a guide for doing maintenance & tune-ups, but my guess was probably way off, thinking the motor had a lot less miles on it , thinking i did'nt have to do the timing belt just yet, but really, not knowing the mileage should of been reason enough to get the timing belt done right away, to have piece of mind, knowing it was done & to prevent it from snapping, causing damage.

also i thought since it appeared in good condition without any signs of wear and had good teeth and not any tears in it, that it did'nt need replacing yet.


after getting the car towed back home, i searched online about people's timing belts snapping, and a lot of people say its 50/50, that some people are lucky and it did'nt damage anything and for others, it did do damage,

people said the first thing would be to put a new timing belt and water pump and set the timing and do a compression check, and try to start it to see if it runs, and it might just run with no problem, or it won't and you know it has damaged stuff, and then you would have to replace the damaged parts.


i wanted to get people's responses and opinions on what they think is the first step in trying to find out if it did any damage or not to my engine and to get towards trying to get my car back on the road ???

thanks for any input you can throw my way,

yeahd00dshaun

It's a non-interference motor so there shouldn't be any damage. Just have to set the timing again and you should be ok. Unless you have some performance parts in there.

chase7687

Your good man. I have a DOHC Zc in my ef and the same thing happened to me. I was able to cost into a gas station where i found the timing belt to be snapped. I brought it to a local mechanic that was able to diagnose a bent valve. I got the head machined to insure no major damage and compression problems and I didnt have to replace my water pump. The only problem I have now is that the engine has developed a little valve lash, but thats an easy fix with the right tools. You should be ok. Just go and get someone to take a look at the head and valves and get you a new belt. This was the hardest part cause ZC engines take a variety of parts from different engines. I had to research and found out a Mitsubishi Expo belt was a good replacement. Hope i helped you out some.

Aesthetic Gains

iTrader: (1)

I blew my ZC up after snapping a timing belt. i was also revving it to 8200rpm lol.
To be young again... lol
If you got access to a leakdown tester you could find out if your motor junk or not.
Simply do a leakdown test with the valves closed on each cylinder and see if it holds pressure. If not, you're screwed.
Anyway, you better hope nothing got hurt while you were trying to start it.
If you can't do a leakdown then put a new belt on it and go from there.

jlicrx

not true - the DOHC ZC, as with most Honda engines, is an interference engine - chances are pretty good that you have a couple of bent valves - if not from when the belt broke, possibly from when trying to start it with no belt - the timing belt you need is the same as for the 88 Prelude Si model - tensioner and water pump are the same as 88-91 CRX/Civic Si D16A6

Vagitarian

Sounds like you definetely tried to start it way to many times and held it cranking after the belt snapped. I would for sure count on bent valves.

For the $500-700 you can source dohc zc's for now adays I wouldnt tear into the engine, I would simply buy a new timing belt, install it, do a leak down test, if you get real lucky and its fine then problem solved.

But if valves are bent I would buy a new dohc zc, and install your brand new timing belt on that motor. And youd have a spare motor for parts and sell the old engine for scrap aluminum to make 50-75 bucks back, and youd have piece of mind knowing your new motor has a new timing belt

Its not worth the hassle and possibly problems of dismantling the engine and getting it worked on etc to me

crxaddikt

i talked to a mechanic friend of mine, and he said first thing to do would be to turn the crank pulley to see if it rotates around freely, without any binding or getting stuck, etc..., cause if it does then means stuffs damaged, but if the crank pulley rotates around freely, then you can try putting a new timing belt (said probably don't need to put water pump unless its leaking or something), and then try and start it, and see if it turns over and runs or not ?, i don't know how to do timing belt replacement, and he said he would charge $125 to do timing belt, which just take him couple hours.


does all of that sound like the right thing to do to everyone ??, or got anything to add that might be left out or that i'm missing ??,

and whats the procedure to turn the crank around to find if its binding or not exactly ???



i'm really nervous about the outcome of this, just because i have got so much fixed on my car within last couple years, and everything was running good, and to me the one thing i was never worried about was the motor, since it was in good condition, but now the worst thing that could happen, happened, and all because i put it off too long !!

1991civiclx13

take your spark plugs out and try to manualy turn your engine at the crank, if it does not bind its a good sign

grant97teg

Leak down first, $125 is fair considering $300 for a shop

crxaddikt

is it necessary to have to do a leak-down test ? could'nt i tell if any valves or internals were bent by just turning the crank around ?

cause i read what a leak-down test is and how to do it, and it says you need some source of compressed air, and i don't have an air compressor or any way to do that? and can't drive the car anywhere to use one since it has a snapped t-belt anyway.



what items would i need to buy if i were going to be putting a new timing belt on ???,

just a new OEM timing belt, but any other parts that you need to get new before doing it, such as tensioner spring thing ? or any gasket type parts or other ??


also, people said to put a new water pump while your at it, is it easy to just test to see if the water pump is in good condition or not ? or is it best to just put new one no matter what ? cause it has to be as old as the engine, which i'm guessing has around 130,000 miles or so.



if the worse case scenario is that some valves were bent, is there usually hope to be able to still fix it some way ? so i can use the same engine again ? like by replacing valves ? or any other stuff that was damaged ?

or does it usually damage other things inside the engine, like the surface walls of the inside of the engine or head etc ??? , where it ruins the whole motor, making it impossible to be able to fix ??


any info would help, thanks

DCRB

do what's best for you.

however, going through high school, my shop teacher, who was a retired ASE certified Diesel mechanic preached to us that whenever you do the timing belt you do the water pump as insurance, because sure as you know it it'll start leaking shortly after you replace the belt.

but more so, why wouldn't you do it now since the belt is off any ways? don't be cheap. do it the right way the first time so it doesn't end up costing you more in the long run.

the point of doing a leak down test is to determine if you do in fact have bent valves, as apposed to just running the engine and putting excessive wear on the valve guides, which will add to how much more money you have to spend to repair the problem.

another thing you can do is a compression test, if the numbers are different then you know you have a leak

you can rent the tool from autozone, and then return it for your money back.

if valves are bent simply get the head pulled off, then take it to a machine shop. have them re surface the head, have them lap the valves, buy new valves to replace the bent ones, from what i've read the d16a1 valves are the same as the zc ones, then slap the head back on with a new head gasket, timing belt, and water pump and you're good to go. also, for piece of mind, get a set of arp head studs, SO worth the money and the piece of mind.

crxaddikt

thanks for the detailed reply DCRB, that makes me feel a whole lot better, and have more hope, instead of being all nervous and worrying to death, thinking it messed my engine up to the point of it being useless.

i did'nt know what you meant exactly when you said :
"just running the engine and putting excessive wear on the valve guides, which will add to how much more money you have to spend to repair the problem"

when you say "run the engine", do you mean like if i just put a new timing belt and just started the engine to see if it runs and is'nt bad? but that it still can mess some stuff up further inside, if you run it without knowing if stuff is bad inside or not ?

so i can just do a compression check since i don't have access to an air compressor ? does it do the same job at telling me if i have bent valves and stuff or not ??


thanks

singlecamsaint

most defintly, if you have bent valves and you do a compression check your numbers for example would be like 125 60 122 118, the one with 60 psi is would be the one that needs attention. i wouldnt turn it any further until you can get it set in time. but that doesnt just go for bent valves a low compression value can mean a number of things, but in your case id at least try it. i know i broke a belt on an accord i used to have, killed 2 intake and 2 exhaust valves...

crxaddikt

just wanted to post and update where i'm at now :


i finally had a free day sunday and got that mechanic guy i know to come over while it was still early enough, he was charging $125 to do it, which was reasonable.

and he was working on getting the stubborn crankshaft pulley bolt loose, and first was trying to use the starter method but was'nt working, and he used his impact gun but had no luck, and then i mentioned a few other methods i saw people say on here, which was taking the starter off and jamming a heavy-duty flathead screwdriver into the flywheel preventing it from moving, and he tried that and kept messing with the bolt whiel i held foot on the brake and had it in 3rd gear, and finally after couple hours it seemed, he got it to come off !!!!, and said it was ridiculously tight, and he almost has never seen one he worked on that was that tight, and usually he is able to get them off way quicker.

so i was happy that part was taken care of, then next i helped him line the timing belt up and stuff,
and he got so the cam gears "UP" arrows were both sort of close to the upward position, but they were off where one was more to the left and the other off to the right more, but i read that the cams on the Dohc ZC's are normal to be like that, so hopefully it drives ok after.

we got everything back together and he told me to try to start it, and it would'nt start from doing it with the key and ignition, but instead he told me to hold the key in the ignition to the "on" position, and he did something in the engine bay like touched the starter terminal with a wire coming from the battery, and he got it started that way, and i was real nervous still to see if it was damaged from the timing belt snapping, but it was running steady and smooth, almost like it was before, and he said should'nt be any damage since its running like that, and only thing i noticed was the valves were ticking louder like they got loose or something, but i did'nt drive the car yet, and turned it off and we were tired and hot and needed to go in for a break and have some water and stuff....

next day after he was gone i was going to try to start it but it did'nt start, and after looking at everything, i realised i needed a new battery, so i got a new one, and tried and it almost started but the starter was only held on with one mounting bolt, and the stress of it trying to turn cracked the hole where the one bolt went through and the starter came off after trying to start it.

so now i just got the long mount bolt for the other hole on the starter (which i was missing before), and after putting that one in good then it should start fine, cause that hole on that side has never been used so would'nt have a crack or any stress put to it, and later i guess get new body for the starter or get rebuilt so i can have a good complete mount hole on it again, since that one broke off.

chase7687

Yeah man looks like you and I have experienced the exact same problem. My belt broke and i had to get a new one. Since then my car has ran just great, but the whole problem with the "ticking valves" has made me worry as well. I'm having this problem where every time I give my car gas and let off the pedal the RPMs drop drastically and sometimes it even dies. Not sure if this is related to the ticking but it would help me figure it out if you start having similar problems. A buddy of mine told me that the valves were out of sync or something and it was causing valve lash. hope some of this stuff helps out man and hoping to hear back from you about those problems. P.S. where you from man?

crxaddikt

chase7687 -

i am in dallas area, where you from ?

so you were lucky too ?, and had timing belt snap but without having any internal stuff damaged? what kind of motor do you have and how many miles were on it when it happend ? i realise its my fault for letting it go too long without getting timing belt replaced sooner, but it was partly due to me not knowing what mileage was on the dohc zc motor i had because of it being an imported "used" engine, and all they do is tell me it supposedly should have somewhere around 30,000-40,000 miles on it, but theres no way of knowing exactly?.

and it was swapped in 2003 after blew hole in original d16a6 cause rain getting in long intake on real flooded day, so all these years since 2003, i was just making a guess as to what miles were on my zc motor, and in the end i was way off, and was kind of thinking it maybe had around 100,000 - 115,000 miles, but its probably a little closer to 135,000 - 145,000 realistically, and so its not a surprise my timing belt snapped, especially cause i was dumb enough to have the top timing belt cover left off for a couple years, and it might of caused the belt to get worn quicker or get dirty or oil on it etc. . ., but reason i did that was i had trouble with closing the hood while the top timing cover for the zc was in place, and with it off the hood closed with no problem without forcing it or pushing it shut, but later i cut a section out of that insulation soundproofing stuff on the underside of the hood, and since then it clears easier cause it sort of fits in where the section i cut out is.

even if i was right with my first guess, if it had 100-115,000miles, then thats still considered pretty late for getting timing belt replaced, cause i heard supposed to around 60 or 70,000 miles, so since i waited up til 135-145,000 miles then it was bound to snap, cause thats waiting way too long before getting it replaced.


as far as the ticking, or the way the car drives, i never mentioned that part on this post, cause i did'nt get it running yet, but recently i did get it started cause i got a new battery cause other was drained almost completely and already old, and made the connections to the starter more secure, and it took several start attempts where it just made a click sound without any crank, but then finally it started and i drove it around slowly and carefully around the neighborhood, and just to make sure it acted ok and did'nt have anything funny happening since after the t-belt snapping, and i was really pretty surprised and very happy that it was running almost just like it was previous to having the t-belt snap, but i still don't feel comfortable punching it so it revs high up in the rpms or anything like i used to drive it sometimes, just cause i want to know for sure its ready for being used like that first.

and so i drove around for almost 30 mins probably, and ran it thru a car wash at chevron to clean all the crap since sitting over 3 weeks, and its parked under some big trees so theres lots of birdshit and sapp all over it and dirt, so got all that off.


and sorry to say it but i was lucky and mine did'nt seem to have the problem you were talking about, where it dropped in rpm or anything, to me it was all pretty good, and smooth, and idled steady and rpms smooth while accelerating, and even the valves did'nt seem ticking loud or loose like they did the day he first put the belt on and got it started for first time, i don't know why, but they almost sounded like they did before which was'nt too bad, but i still am due for doing a valve adjustment anyway cause i have'nt done one since probably 2005, plus probably good idea to do it after a timing belt has been snapped just cause it might of shifted the valves or some crap i don't know about?, i know people say it does something usually related to valves, like either bending them or whatever, but since the valves are held in position with screws and settings then it can maybe mess with those also when it snapped ?
(just guessing)

so i just feel better if i do valve adjustment and also i'm goint to check ignition timing with timing light to just make sure its set where it should, plus i'm going to do some other stuff, like i noticed oil is in all of the 4 spark plug holes but i don't understand why cause i replaced the O-ring gaskets for the spark plug tubes only like 1 year ago ? along with the valve cover gasket too ??, so not sure why oil still coming in around them ??


sorry could'nt help you out with any weird problems you are having since the timing belt snapping, i would but i don't have any similar symptoms as you, if i did then i would be able to describe and compare how they were to how yours was acting, but since i don't, i really have no idea why it would be doing that with your rpms and stuff ?

are you sure when you put the alternator belt back on after doing the timing belt install, that the alt belt was at the right tension and adjusted so its tight enough ? cause could'nt it affect rpms or how it drives if the alt is'nt turning right if the belt is loose around it ?

or what about, are you positive the timing belt is adjusted properly and at the right tension and stuff ??

read this post i found, it could be something like this ? (they have prob w/ rpm dropping when giving gas too)
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https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/weird-problems-rpm-drop-when-coming-stops-lights-brighten-dim-night-2997274/

you should make sure alt is good, but i don't trust when they test them at auto part stores, cause i remember in the past autozone tested my alternator saying it was all good, but it still turned out to be bad later on, and i ended up replacing it and fixed whatever problem i was having at the time, but i almost overlooked the alt cause i was trusting their test, cause they said it was good, but someone else told me just try to replace with new one anyway to see if solved prob, and if did'nt then you could always take back the alt anyway, so i did that,

also they say make sure you got all good grounds on everything like battery cables and valve cover, and the ground from battery to starter and to body on middle of neg. cable of battery too, and make sure your idle is set right and that it idles steady, also i wonder if anything related to the fuel delivery system could do anything with how the rpm drop when giving gas ? like what about is the fuel injectors good ? or fuel pump ? fuel filter? main relay ? (i don't know, i'm just throwing some stuff out there, to maybe try helping you out to pinpoint the problem)

i don't know much about valves being out of sync or "valve lash", but i've seen lot of posts after doing a search on here, related to timing belts snapping and having "valve lash" afterwards, i would search about that and read about how it affects it,

all i know is how do valve adjustment,

are you sure timing is set right and everything with the "up" mark pointing up ? and horizontal marks lined up on the side and the marks on the crankshaft lined up to timing cover and all that when you had timing belt installed ??

even if it did'nt bend any valves after your t-belt snapped, is there a possibility it could of done some other type of minor damage inside ? like scoring the surface of the cylinder head ? or moving valves around or anything like that, that could affect how it drives and the rpms acting the way they are acting ?

you could get a compression or leak down test done cause i heard that can tell for sure if theres any damage for sure, cause mostly i hear if valves were bent it would'nt even start or would run like total ****, so yours did'nt do that, cause yours runs but just has something minor that is acting strange, so i was just thinking maybe its cause it damaged something other than bending valves ? like something else minor ?


i don't know, but just trying to think or give you ideas

Nooch

You were willing to risk 60,000+ on that timing belt? On top of the already suggested 30-40000 miles? Holy hell man, no **** that's gonna break. I'll be honest I didn't swap my timing belt either when I got my motor, but I checked it and it looks brand new anyways. I baby the **** out of the engine 95% of the time. I never redline it or anything stupid. Maybe put 20,000 miles [MAX]on the engine since. I'll probably be selling my car soon and don't care too much to replace the timing belt beforehand. But if I keep it, it will be changed in max another 10,000miles.

94EG8

A. You really can't determine the condition of a timing belt without taking it off and flipping it over, the cracks will be on the inside and you have to turn the belt around the wrong way to actually see them.

B. Timing belts can and will break at idle. And breaking one at idle doesn't lower your odds for bent valves either.

DCRB

i'd still do a leak down test just to be on the safe side. on my a6/z6 mini me, i took my belt off to replace my water pump and set the crank at tdc for cylinder one, then tried to move the head around, and it wouldn't move much due to my valves touching the pistons. so maybe you got lucky.

but what i was talking about is inside the cylinder head, theres the holes drilled out for the valve stems, which generally have valve guides pressed into them to take up the space between the aluminum head and the steel valve stem (dumming it down here a lot). when the valve bends, you're potentially forcing a bowed piece of metal through a strait tube, which will put excessive wear on the valve guide

crxaddikt

Nooch :
yeah, i know i was dumb for letting it go that long, without having replaced the timing belt yet, i procrastinated too much, and instead i was using money to get other things done on my car to-do list, such as get starter rebuilt, new battery, new tires, $380 at susp & align shop, new window cause car broken into, master cylinder . . .

and all that time i knew in the back of my head i needed to get timing belt done soon, but i also thought it cost couple hundred to have done, and could'nt afford it.

i also thought it was ok just cause my timing belt looked all new and smooth, in good condition, and that it looked like it was sturdy enough to do its job of turning the gears and did'nt have any signs of damage or getting old, but i later learned to not go by its looks.

(surprised you read all of what i wrote lol, cause i just saw it today & didnt realise how much i typed)

crxaddikt

DCRB :
so your saying that even if my car runs almost exactly how it did before snapping the timing belt, that its still a good idea to get a "leak down" test ? or "compression" test ???,

is it cause it could still have some type of damage inside? even if it seemed to run fine? cause i could'nt feel anything different about it or in how it drives? and mechanic guy who worked on my car said its fine, and that if i had bent valves that would'nt probably even be able to turn over, and if it did, that it would sound and run like total ****, so he thought it was fine, but i like to be on the safe side,

i guess i can get a leak down test or compression test, it would be good out of curiosity also, to see if it affected anything like the pistons or rods or inner workings, be good seeing what the numbers show to know of anything even if it did'nt have anything to even do with the timing belt thing, cause then you can at least know to prevent something worse from happening.