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Old 09-08-2009, 11:19 PM   #1
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Default Engine rebuild, now no compression

I just finished reassembling my 1.6. Ive done:
new rings
rehoned the cylinders
new bearings
new oem type valve springs (beck arnley)
new supertech exhaust valves
cleaned off the original intake valves
valve seals
disassembled the lifters, cleaned and reassembled
timing belt
head gasket
various other seals and gaskets

It cranks fast as if theres no compression, and my compression gauge reads zero on all cylinders. Compressed air hooked up to the cylinder 1 plug hole seems to blow out the intake and exhaust, nothing up through the crankcase or out the dipstick tube. I believe its timed right. The marks all line up, the pins on the cams are pointed up and I verified cyinder 1 tdc with a screwdriver down the spark plug hole. The cams dont appear to press the cylinder 1 lifters down at cylinder 1 tdc, so my next thought was that I reassembled the lifters with too much oil in them, causing them to overextend. I took them out and drained and recleaned them, reinstalled with no oil in them. Same problem. I believe I seated the valves completely, but this is my first time getting into the internals of an engine. Im running out of ideas now, so any insight would really be appreciated.
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Old 09-09-2009, 12:11 AM   #2
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I would double check that it is timed right. Maybe take pictures of the gears and show us.
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Old 09-09-2009, 12:37 AM   #3
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did you lap the valves?
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Old 09-09-2009, 12:47 AM   #4
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My guess is that your timing is way off.
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Old 09-09-2009, 01:49 AM   #5
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either way off cam timming or your valves are flaoting in space and not sealing the combustion chamber before you take off the head. i would check the timming agian, and if it is 1000000000000000000% correct then i would be inclined to pull the came and or allow the valves to enter there fully closed position with no laod holding them open whatsoever and perform a leak down test if this does not go well then you need to pull the head and possibly the motor and get to the botom of this.
If this does work, obviusly something is binding your valves open or they are to long for some unknown reason to seat properly.
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Old 09-09-2009, 01:59 AM   #6
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Tomorrow I will quadruple check my timing, and post pictures here. I hope you guys are right and it is a timing issue. Hustler, Im assuming lapping valves = seating valves, and yes I did. Im not entirely sure I did it the right way, but I ground the valves into the seats til there was about a 1mm mating surface all around. It looked to me like the valves would have no problem sealing. But I think Ill pull both manifolds off tomorrow to try to look at the valves. Thanks for all the help so far.
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Old 09-09-2009, 02:05 AM   #7
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Originally Posted by magnamx-5 View Post
either way off cam timming or your valves are flaoting in space and not sealing the combustion chamber before you take off the head. i would check the timming agian, and if it is 1000000000000000000% correct then i would be inclined to pull the came and or allow the valves to enter there fully closed position with no laod holding them open whatsoever and perform a leak down test if this does not go well then you need to pull the head and possibly the motor and get to the botom of this.
If this does work, obviusly something is binding your valves open or they are to long for some unknown reason to seat properly.
I did pull the cams and blow air into cylinder 1, I did here some air blowing out the intake and exhaust but it was less than with the cams on. I dont know if this is normal. Im not sure what exactly a leakdown test entails, and I dont have access to a leakdown tester.
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Old 09-09-2009, 02:23 AM   #8
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Originally Posted by bengxe View Post
I did pull the cams and blow air into cylinder 1, I did here some air blowing out the intake and exhaust but it was less than with the cams on. I dont know if this is normal. Im not sure what exactly a leakdown test entails, and I dont have access to a leakdown tester.
if air is still escaping then your valves are not seating or your rings where not done properly. At this point i would call someone who has rebuilt a motor before man becouse you have screwed up somewhere and hopefully with someone there in person you can fix the problem as, painlessly as possible. At minimum you will need to pull your head, but seriusly find someone with experience to help you if you can or if you cant then take it to a pro for a overview. At the most it should be 400-500 dollars letting them check it for you.
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Old 09-09-2009, 02:39 AM   #9
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Thats exactly what I was afraid of, and what most people told me to do in the first place. Now Im wondering at what point do I cut my losses and find a low mileage 1.8.
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Old 09-09-2009, 02:57 AM   #10
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Make sure your cams are oriented correctly. Perfect timing doesn't help when there are valves open at TDC.
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Old 09-09-2009, 03:07 AM   #11
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Originally Posted by bengxe View Post
Thats exactly what I was afraid of, and what most people told me to do in the first place. Now Im wondering at what point do I cut my losses and find a low mileage 1.8.
lol dude you didnt blow he motor up you just missed something somewhere. My bet is once youget a freind along with you with alil more experience you will see what your problem is and it could be simple or complex. Dont throw the baby out with the bath water in your postmotor build depresion.

And save his stuff isnt sealing with the cams off ie valves should be 100% closed this tells us something is done wrong somewhere.

Last edited by magnamx-5; 09-09-2009 at 03:36 AM.
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Old 09-09-2009, 03:27 AM   #12
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Another vote here for check the timing. Even if the rings didn't seat well and the valve seats are leaky, it would still show something on the gauge.
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Old 09-10-2009, 03:17 AM   #13
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Heres my timing marks. I couldnt get a picture of the crank pulley to turn out well enough to be useful, but I found tdc with a screwdriver down the plug hole and then verified it with the notch on the crank timing belt cog.


This is what my cams look like at cylinder 1 tdc.

I pulled the exhaust off to look at the back side of the valves, but didnt see anything wrong (couldnt see much). Tomorrow Ill pull the head.
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Old 09-10-2009, 10:38 AM   #14
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If you still have the cams out, you could put each cylinder at tdc and shine a bright flashlight into the plug hole. If the valves are not sealing you will be able to see light when looking through the intake and/or exhaust ports for that cylinder.

I'm also wondering if something happened to your lifters when you took them apart. Possible that they are not depressurizing at all and are actually lifting too high. You should be able to squeeze them by hand.
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Old 09-10-2009, 10:42 AM   #15
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Not that it's in any way related to your compression problem, but:

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Old 09-10-2009, 11:07 AM   #16
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Good catch, that sucker is on backwards. I hope those things are in the correct order. That picture does not leave me with a feeling that they are.
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Old 09-10-2009, 11:45 AM   #17
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^ you better swap that around before you get some aluminum dust floating around your engine.

I've seen a head that had the valves cut one too many times- they wouldn't seat.
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Old 09-10-2009, 12:15 PM   #18
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Is it possible the valves are 1.8 valves? Larger head and longer iirc.

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Old 09-10-2009, 02:21 PM   #19
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Not that it's in any way related to your compression problem, but:
Thanks for noticing, but its already fixed and it never cranked like that. I was taking the cams on and off alot when I took that picture, the bolts actually werent even torqued.
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Old 09-10-2009, 02:25 PM   #20
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I'm also wondering if something happened to your lifters when you took them apart. Possible that they are not depressurizing at all and are actually lifting too high. You should be able to squeeze them by hand.
I think this is it. I think the tiny inner plunger is backwards on all my lifters. Im going to switch them around after work today. And Im hoping I didnt bend any valves.
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