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well....crap. please help


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Yeah, leakdown test is next on the list. Cams were installed correctly. And yes, they are labeled L-intake, L-exhaust, etc.

 

I'm taking today off with this car. I spent three 16 hour days tearing it apart and putting it back together. I just need a break

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Also check all fuses, here's a timing mark chart that you can double-check with.

 

And when you think everything is right - rotate engine by hand a number of times to make sure no interference occurs, that way you won't damage anything at least when cranking.

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Those leakdown numbers seem pretty good. Looking through this thread, ALL you compression test numbers suck ass. 40-50psi for everything, am I reading that right?

 

You should be seeing 125psi give or take 25psi depending on cold/hot/wet/etc motor and all 4 cylinders should be consistent.

 

If you are truly at TDC, the rotating assembly *shouldn't* move when under pressure, even at 100psi or so. Maybe try using a socket extension instead--tape on one end, stick it in there, crank until it stops getting pushed out, perform leakdown test.

"Bullet-proof" your OEM TMIC! <<Buy your kit here>>

 

Not currently in stock :(

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I tried, the engine is in the car already and can't fit anything in the holes. Used a 1/4 extention and a long skinny flat head (taped of course).

 

Light bulb! I have a flex piece that might work. Ill give that a try and run the numbers again tomorrow

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The,compression does suck, which is why I still think its timing related. Maybe a new gates timing belt,kit is in order?!? The TB was replaced less than 10k miles ago and looks great so i just reused it. Think it stretches enough to throw timing off?
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Yeah, I'm pretty confident they are on right, but I'll double,check. They wouldn't sit flush if they weren't aligned properly anyway. And since the right side looks perfect according to the leakdown, there's no reason to suspect they are on wrong amd yet they still habe stupid low compression
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Are you positive the dowel pins of your camshafts were aligned correctly with the cam gears? If not, the timing marks could look fine but in reality, the timing is off.

 

Yeah, I'm pretty confident they are on right, but I'll double,check. They wouldn't sit flush if they weren't aligned properly anyway. And since the right side looks perfect according to the leakdown, there's no reason to suspect they are on wrong amd yet they still habe stupid low compression

 

Hate to say it, but this is EXACTLY what happened with my own motor. I did NOT press the cam sprockets on or draw them on with bolts, somehow it just "happened." I'm no noob on these cars either.

 

The problem with this issue is that a leak down test won't tell you anything because you are physically putting the cylinder at TDC, not by using timing marks but by physically feeling piston location either with air as you mention or with a screwdriver, socket extension, etc.

 

Sounds like you need to check the cam gears.

"Bullet-proof" your OEM TMIC! <<Buy your kit here>>

 

Not currently in stock :(

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And they will sit flush because the metal is soft enough that they can be drawn into place such that the cam dowel just makes a new hole. In my case, the dowel just went into an existing oil galley hole and enlarged it just a touch to fit. For whatever reason the resistance was close to nil because they all went on by hand and I verified cam movement by hand since the motor was on a stand and the valve covers were off. I'll still never really know / understand exactly how it happened in my case, but it did.

"Bullet-proof" your OEM TMIC! <<Buy your kit here>>

 

Not currently in stock :(

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Hmm...but if it was just slightly off, I would still get pretty damn good compression, right? I'm still going to double,check, I just think its doubtful. I actually hope you're right!!

 

Well, if testing compression based of FSM instructions, you would only have an issue on the side that you screwed up on--unless you incorrectly installed a sprocket on each side? Hard to say. But FSM compression test instructions are based on timing marks, not physical piston / valve location. So if compression numbers or crap, and leakdown numbers are good, it could certainly point to misaligned sprockets.

"Bullet-proof" your OEM TMIC! <<Buy your kit here>>

 

Not currently in stock :(

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Wait a tick....how can compression test be based on timing marks? You plug the gauge in, and crank it over. Timing marks won't line up or even matter?!?!?

 

Sorry, you're right. I think I'm talking entirely of leakdown testing. You can do it either based on timing marks or based on physical inspection of piston location to determine TDC. Try it based on timing marks per FSM and see if leakdown test numbers are the same.

"Bullet-proof" your OEM TMIC! <<Buy your kit here>>

 

Not currently in stock :(

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Are you saying that you were having trouble getting the LDT threads into the sparkplug hole threads?

 

If so, I just take it very slow and turn the LDT connector counter-clockwise with slight inward pressure until I feel the starter thread drop into the spark plug threads, then start turning gently clockwise until the LDT connector threads are tight. A little motor oil helps this.

- Pro amore Dei et patriam et populum -
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