Timing Issue..... Rebuilt engine and sounds like timing is off! 2007 5.7

Hi just seeing if anyone has some ideas I rebuilt my engine on a 2007 tundra 5.7 (Kind of a novice last engine I rebuilt was like 45 years ago on a push rod basic engine)

The truck started but ran really badly. Lots of bank 2 codes on the obd scan.

I checked the compression and Bank 1 has like 200 psi. The bank 2 cylinders all have 30psi. I know that I must have done something wrong on the bank two side. Any ideas? Maybe timing chain off by a tooth, chain installed incorrectly, camshaft in wrong slot?

I looked inside the cylinders with a borescope and looks like there is no damage.

Thanks David

 

Lots of ideas of what could go wrong with that. Did you have a guide that you used to assemble step by step, or were you winging it?

 

I kind of winged it. The yellow and orange/red chain links were definitely lined up with the notches in the top 4 sprockets. I am 99% sure the two bottom orange/red links were lined up with the crankshaft gears in the proper place. Is there anything else I would have had to do with those upper 4 sprockets to make sure they were in the correct position?

 

Have you performed a leak down test to see if the valves are open on bank 2?

 

I’m very methodical when it comes to something like an engine rebuild. Step by step. Organized. Check my work. Follow the torque specs. I personally would retrace all your steps.

 

I do not know how to do a leak down test... but I pulled the valve cover off and all the chains are still connected

 

A leak-down test is very easy if you have a tester. I will be buying one after borrowing one from my neighbor this past weekend. They tell you so much more that a compression test ever will.
This is the one that I used. There are lots more out there.

$99 OTC 5609 Cylinder Leakage Tester Kit , Black

https://www.amazon.com/OTC-5609-Cyl...ocphy=9017483&hvtargid=pla-2281435181738&th=1

 

pulled both valve covers off and the timing looks spot on yellow with yellow and the orange and yellow all line up on top. I have pictures if that helps. We also checked the cam gears and they seem to be in the knock pins. I am baffled still 200 psi on bank 1 and 30 psi on bank 2. No damage to pistons or valves.

 

I know that it is a huge job to confirm, but do you know that your timing mark is right on the crank?

I would find top dead center on one of the pistons on each bank, then compare that cam position on each bank. With the respective piston at TDC, the cam lobs should look to be in exactly the same place rotationally. This feels like the problem since it is all four pistons on bank 2.

If it is not a timing problem, then I fear that you have a much bigger problem that will be even more work to solve.

 

I hate to suggest this, cause it's a ton of work. Take the front cover off and realign the timing marks. Check, double check and triple check. I'm a former ASE mechanic and the 5.7 is easy to screw up. The chain links have to be exactly correct on the cam gears when the crank is in the perfect position.

 

Currently I have on the driver’s side intake 13511 0S010 Drivers side exhaust 13512 0s010 passenger side intake is 13513 0S010 and passenger side exhaust is 13514 0S010 it seems the sides are switched but in the correct intake and exhaust position is there a unique difference between the 4 cams and could this be the issue?

 

Just an update we changed the cam shaft order to the proper side and the truck runs much better. Definitely the 4 camshafts are unique to each other. Now that I have reassembled it makes a clicking sound (Like a diesel engine) on the driver’s side near the front of the valve cover which I think is the secondary tensioner. I am guessing we banged it up on the cam swap.

Just a quick question regrinding the primary chain that goes to the crankshaft should the side going down to the crankshaft be less tight than the side coming up from the crankshaft? So the opposite side of the primary tensioner the chain is definitely loser going back to the crank does that sound correct?

 

Not running without oil pressure is not a very good time to determine how tight or loose the chains are. The cams tend to snap into position. This can cause the chain to be loose in either direction with the engine not running.

However, the side that does not have the tensioner on it should be tight as a rule. The tensioner takes up the slack on the loose side of the chain. I hope that helps.