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Discussion Starter #1
Doing head gaskets (and other items) on 2001, 3.3.

How can I verify TDC compression?

All marks lined up and new belt. All looks good, but I don't get any compression from no 1 piston. Took belt off and turned crank 1 complete revolution. Still can't feel any compression.

What gives?

TIA
 

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What was the sign of failure? Overheated then no start? Could have burnt valves. Did you do compression test and leak down test before tearing apart?
 

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Bent valves.Did you take the heads to machine shop for check valves,new seals, crack check ,and deck ???
 

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Discussion Starter #4
Actually, had both heads reworked at reputable head shop. It had a blown head gasket. That was the only thing wrong.

It actually ran fine, just a cloud of steam.

Can't get my compression gauge down on sparkplug hole. Used a screwdriver handle and it didn't seem to have enough compression to blow off the handle. I think I may be 1 revolution off on crankshaft. How can I tell?

And, just to confirm, when passenger head is at TDC and on timing mark and then I put driver head on timing mark and install belt (with marks at proper place) both heads are properly timed, i.e., I can't be off 1 revolution on the driver head? Right?

All marks are lined up.

TIA
 

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Be-careful your going to bend some valves ,4 marks 1 on oil pan 1 on pass head 2 marks on cam wheels with dist rotor pointing to #1 cyl.
 

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Discussion Starter #6
Okay, here's what I did. All marks lined up (2 cam, 1 crankshaft). New belt with mark lined up.

I turned crankshaft and determined that if the next valve that opened was the exhaust valve (on No. 1 piston) I would be okay.

That is what happened.

So, I'm good to go right?

TIA
 

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Discussion Starter #8
Distributor is out of engine.

Only have the heads and intake manifold on right now.

Should I put it back in?
 

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Discussion Starter #10
My issue seems to be the 2 revolutions of the crankshaft to 1 of the cam.

My theory: If I line up all marks (the 2 marks on the 2 cam sprockets and the mark on the crankshaft), I should be on TDC, piston 1, compression.

Is this correct?

TIA
 

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The crank doesn't know the difference between compression and exhaust stroke. You turn two full rotations for every one turn of the cams. Just line up the timing marks and you are good. Repeat, if the timing marks (notches on cams) line up with the timing cover, you cannot go wrong.

If you really want to check TDC, You can also see the piston at the top with a flashlight if you look down in the hole.

The distributor on the other hand, that can be 180* off. If you get it all together and it wont start or even turn over, check the dist. position.
 

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Discussion Starter #13
Okay, everything back together and when I filled radiator, I'm getting a leak from the lower cover (near crankshaft pulley).

Any ideas where this might be coming from. Put a new (not rebuilt) waterpump on it.

TIA
 

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Most likely the water neck or the hose that connects to it. Just in case... did you torque the water pump bolts to factory specs?
 

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Discussion Starter #15
Is the water neck where the thermostat is? Yes, I torqued to those insane specs (140 + lbs, I think).

TIA
 

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Nothing insane about them... Those water pumps hold up great for 100k+ miles. I almost left my factory one in when I did my t-belt and pump... the wheel on it was what appeared to be stainless steel, looked MUCH more durable than the cast-iron one that Nissan sold me to replace it with.

The water neck isthat awkward piece that I think mounts behind the rear water pump cover. Where your top radiator hose mounts. It may be leaking down behind the cover or something.
 

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*mean to say rear timing belt cover
 

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Thats 140 inch lb not foot lb.
Oh snap, I didn't even consider someone would mix that up... hopefully he didn't crack the pump!!

Conversion is simple, I believe you just divide by 12. 140 Inch Lbs. = ~12 Ft. Lbs.
 
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