dychron

Hey yall,

I recently performed a top end rebuild on my 22RE from a 1992 Pickup 4x4.

This included-

• replaced timing chain
• replaced the timing chain guides
• tensioner
• resurfaced the head
• replaced valve seals
• replaced head gasket
• replaced timing cover

Everything went back together without hassle, but when starting the engine for the first time the rpms were quite high and the idle was exceptionally rough.
My suspicion is that my distributor could be off a bit or maybe the chain could have jumped a tooth. Before disassembling everything again I wanted to ask the yotatech community for input on what the issue/s could be.

Cheers,
Drew

Melrose 4r

Check for vacuum leaks.

millball

Easy to check ignition timing and cam/.crank alignment. Do those things.

snippits

Re-stab the distributor. As it drops in the hole, the rotor will rotate counter clock wise. Easy to mess up on these engines. Set timing with light.

scope103

Hey, why don't you start with the timing light? If the timing is within 10-15°, the problem isn't the distributor installation. (mis-installing the distributor will set the timing off by ~28° per tooth missed.)

dychron

I will restab the distributor today and report back in since the timing seems to be off a bit more than 28 degrees

tyvanwie

I had similar issues after installing the same parts you did. Timing somehow got cranked up. Set it normal and everything is good.

dychron

I did ended up finding the time to work on the truck this weekend and found out that the distributor was off by one half rotation. I also pulled the valve cover and saw that the chain may have jumped a tooth? So I'm assuming I will have to go back in and repair that. Now I am curious to how could I find out if I may have damaged valves while previously trying to start the engine?


Timing chain jump

scope103

Are you sure? If the distributor was "180° out", the plugs are firing at the top of the exhaust stroke, and I can't imagine it would even fire, much less run.

A compression test will give you a good indication. A leakdown test would be more useful (you don't need the fancy gauge, just the compressed air, as all you're really doing is trying to listen for escaping air when the piston is at TDC on the compression stroke.)

old87yota

Just like timing belts, the timing marks (bright links) on the chain are not really relevant after the engine has been rotated. The bright links are only there to make sure there are correct number of links between the crank sprocket and the cam sprocket when the chain is being installed. Because the chain is not the same length top to bottom on the tensioner side compared to the driver's side, the bright links will rarely line up with the marks on the sprockets after the engine has been rotated.

To check if the mechanical timing is still correct, look to see if the crankshaft pulley and the cam dowel pin are both straight up.

dychron

So I did a leak down test today and each cylinder checked out within 10%. The chain bright links varying after turning over the engine is news to me but it seems that the cam notch is aligned with the crank mark. Any advice on where to proceed?

Co_94_PU

iTrader: (-1)

That ten percent number isn't relevant you have no prior tests to compare it to, what you should have been looking for was where the air was escaping (intake valve, exhaust valve, position ring, head gasket)...

Let's just back you up here a bit, put the wrench's down and check your firing order, ignition timing, and vacuum system for proper routing. Once you go over those a few times and find nothing you can reconsider mechanical issues, but it's still more likely a "simple" issue.