I recently did the timing belt on my moms car, 97 civic d16y8 manual, it snapped while she was driving. So far i’m unaware if the valves are bent i figure i’d just do the belt and see if it started up. A few issues i’m having, with the crank pulley removed, i’m able to spin the motor by hand well with a ratchet to set all the timing marks and all, but when i put my crank pulley back on, im unable to spin it anymore no matter how much strength i put into it. i buttoned everything up and tried to start it but it’s a no go. it acts like it wants to start but just won’t do it, getting a lot of motor movement as well. could it be bent valves? mechanical timing issue? any help i’d appreciate !!

 

Sounds like it could be bent.

Crank will spin easily without timing belt and once cam is engaged, if the valves are bent bad enough it could cause binding. You also don't know if there is piston top damage if you didn't scope it to see.

A leak down is the easiest and fastest way to confirm bent valves.

 

that’s what’s confusing me is that i can put the timing belt on and everything, just without the crank pulley being on, and i can rotate everything. the cam will rotate with the crank, but as soon as i put the pulley on, nothing.

 

Do you have the crank timing gear installed backwards ?

 

everything is installed the correct way. the only thing, and i don’t know if it matters, but i looked for some videos and when other people out there crank pulley back on it goes all the way on easily by hand. mine doesn’t, it’ll only get about a lip on and then i have to tighten the crank bolt to get it to seat all the way back.

 

Be sure the washers are curved away from the belt. They are slightly curved and they are to align the belt to the gear. If they are put on backwards they bind into the belt.

Can you spin your water pump by hand without the belt? Can you spin the tensioner pulley by hand without the belt?

You can't set timing belt tension without rotating the assembly so something must not be installed correctly or something is seized up (causing the break maybe?) in the assembly.

 

yeah the washer is curved towards the block, so that’s right. i can spin everything by hand as long as the pulley isn’t on. i put the crank bolt in without the pulley, and i’m able to turn it a few times with the belt on to make sure the timing marks still line up and i spins freely it feels fine. everything pretty much works fine up until i have to put the pulley on then nothing will spin.

 

Are you using the factory crank pulley ?

 

yes it’s the factory pulley

 

Based on your description..... The crank pulley is binding or a belt from the pulley to something else is the issue. If you can't spin the crank with an empty pulley then the pulley must be binding somewhere on the lower timing cover or squeezing the cover into the outside of the crank timing gear and the lower sensor sprocket on the gear. This makes me think the inner washer (block side) and the gear are not going on all the way for some reason.

You also mentioned you are unable to slide the crank harmonic balancer (pulley) on and you have to "press" it on with the crank bolt. This is also suspicious.

Pics of your pulley and the key as well as the crank snout would be helpful methinks.

 

i’m gonna grab a picture of everything soon and keep you guys updated. i appreciate the help!

 

okay so my bad first off, been caught up with work, but i took everything back apart and it turns out, the crank pulley was rubbing on the lower timing cover pretty bad. i removed it and everything goes on and rotates very smoothly, however, it still won’t start. seems like it wants to start, but won’t. any ideas?

 

here’s a short video of what it’s doing

 

Do you have a compression tester? Should probably check since you may not be building any compression not allowing it to start with the possibility of having bent valves. If you don't, any feeler gauges? Check the valve clearance and if you find some valves with mad clearance then there ya go. Bent valves stuck open. Your video, seems like it's having a hard time just cranking over.. weak battery?

 

checked with a good battery, same situation. now when you said mad clearance, way above the specs? or could they also be too tight ? just wondering before i start looking

 

I was meaning like possibly you could use a popsicle stick as a feeler gauge or just much larger than out of spec range like say exaggerating .050" for clearance compare to maybe .006-.009" for stock clearance. The valve if stuck open will show a oddly larger gap.

 

i’ve only checked cylinder 1 valves so far and the intake valves were in spec but the exhaust are tight as well. couldn’t even get a .001 in there. still have to check the other 3. was just wondering if it was strictly if there was too much clearance, or if not enough clearance would mean the same thing

 

okay so i went out and check the valve lash for the car. this is what i got. the .025+ is just because that’s the biggest size gauge i had. they’re pretty bad. i’m gonna assume those are bent valves. should i get new valves for the head ? or just get a new good head from a friend for $200? appreciate all ur guys help btw

Cylinder 1



Intake 1 - .005

Intake 2 - .0015



Exhaust 1 - .017

Exhaust 2 - .025+



Cylinder 3



Intake 1 - .006

Intake 2 - .005



Exhaust 1 - .014

Exhaust 2 - .011



Cylinder 4



Intake 1 - .006

Intake 2 - .005



Exhaust 1 - .011

Exhaust 2 - .010



Cylinder 2



Intake 1 - .007

Intake 2 - .003



Exhaust 1 - .025+

Exhaust 2 - .025+

 

Getting a replacement head would be the easiest route. If you get it, reset the valve clearance once it's on.. may be off a tad bit after it's years of use.
Also $200 from a friend.. In my area they go for $60-$150 tops..

 

damn 60-150? can barely find any to begin with for me. found a few with bent valves starting at 150 haha

 

When you checked valve lash, first, your mechanical timing is correct? Second, did you put cylinder 1 TDC via FSM methods, then tested lash, then moved mechical timing 180 degrees to put #3 into TDC, then 180 for #4 or #2 (forget firing order) etc? If you didn't TDC each cylinder to test, your valve lash readings are off. When you said you couldn't get a small feeler in on the exhaust side of #1, it makes me think you didn't TDC each cylinder as you went along.

 

yes the mechanical timing is correct, everything is lined up, the crank pulley marks, the cam marks. it’s all there. i tdc’d cylinder 1, rotated 90° counterclockwise and checked cylinder 3 and so on in firing order

 

K just checking. I sold my Y8 head for 250 CAD, they are not cheap in my area any more. The Y8 and the Z6 are a premium now a days here in BC Canada.

I agree getting a head is the easiest solution. If valves are bent, you may need more than just valves and the head may also need guides replaced, that's machine shop work there. You could price it out and see which is cheaper, a new head or parts and labour for guides and do the lapping yourself with the new valves.