Charles Phillips II

so no one has to read the whole post. I found my valves on #1 cylinder were bent. I'm going to local salvage yard to pull some more off a 2001 maxima. Debating on if I should upgrade the intake manifold with this dual runner thing the Org speaks of.


Patient is a 95 Maxima

Going under knife for timing chain replacement due to r.side exh cam shearing off.

after replacing the timing components i decided to do a compression test but i am not getting no reading.

Do i need the upper and lower oil pan attached to get a reading? https://maxima.org/forums/images/smilies/confused.gif

DennisMik

iTrader: (2)

You don't need the oil pan on to get a reading.

If the gauge reading bounces up and goes back to zero while you are cranking the engine, then the gauge probably has its pressure release valve stuck open.

If the gauge never moves, then either the gauge is no good or you have the timing chain on wrong.

To see if if the engine is developing compression, put your finger in the spark plug hole and crank the engine. Compression will blow your finger out.

Charles Phillips II

Here or some crappy shots of some of my timing setup.

1st image is the l.side of engine directly above water pump
2nd image is the r.side towards the firewall

On a side note. In the 3rd image for the r. side timing chain guide (closest to firewall). Is that too much gap for that? I didnt pay attention to that upon removal.

also on the 4th it is from the timing chain kit but i surely dont remember no o-rings being removed

and on the 5th pic where the heck does this assembly go (i think they sent me the wrong part)

DennisMik

iTrader: (2)

Many times a gasket kit will cover multiple make/models and will include things that aren't needed in every case. The o-rings would be needed if you had a 3.5 liter engine (2002 and newer). Your mystery part (pic 5) is the rear main crankshaft seal.

Charles Phillips II

here are some shots of my attempt in re doing the timing

1st shot (Is this the correct position for the absolute tdc? or does it need to be 10 degrees off or something?)
2nd shot is the origianl camshaft chain w/2 gold links
3rd shot is the replacement chain w/1 blue link

there are 10 links between the 2 gold links. so i counted 10 for the aftermarket camshaft chain. The rest of the pics are just my aligning the main chain.

If you see a mistake please let me know

Charles Phillips II

not getting compression from #1 cylinder. Every other cylinder ranges between 100-120. why am i not getting compression from that one. keep in mind that the initial issue of the car was the exhaust sprocket on the back bank (firewall side).

DennisMik

iTrader: (2)

All the photos look good with the exception of the last one, which is the crankshaft pulley.
The slack in the chain makes it difficult to tell exactly, but I think it is one tooth off. Double check that.

Even if the chain is off, that won't account for no compression on only one cylinder. Look at the heads, the ends of the valve stems for cyl #1. Could something have gotten in between the valve stem and the cam and is keeping one of the valves from closing?

Charles Phillips II

read your response and looked down into the intake plenum where you can spot the two valves. Both valves are stuck in the open position. when i look at the tappets on top that the cam lobes strike. they both look dead to the world. is there a spring underneath that has collapsed? on both? is there a way to repair this w/o taking the head off?

DennisMik

iTrader: (2)

Yes there is a spring that pulls the valve closed. Since the tappet/valve lifter sits on top of the valve, it will be pushed up by the valve spring.

Is there a big gap between the tappet and the camshaft? There shouldn't be, just the normal couple thousandths clearance. If the valves ate hanging open, they may be hung up in the valve guides. That should not happen, either.

surban1

iTrader: (17)

this is an "interference" type engine; did the pistons hit the valves due to the above.

Charles Phillips II

not super sure. but upon further inspection i have found that the intake valve (at least) has bent. took the tappet off and pressed the spring down with needle nose pliers. simultaneously with a magnet on the top of the keeper which pulled the keeps and hat away.

anyways i'm not able to move the intake up/down or spin it. Looks like i should just get a used engine and call it a day.

DennisMik

iTrader: (2)

It's a lot of work to swap an engine, but pulling a head off isn't easy either. If you can get a lower mileage engine than what you have, then it may be a good idea.

If you get another engine, put the new timing chain & guides on it and maybe even replace the water pump while it is out of the car.

Charles Phillips II

That is a definite, I have a new timing kit, water pump and thermostat that could go into it. even found an engine with less then 55k on it for $500. It is hard to decide whats worth it though.

Current engine cylinder pressure is 120 across the board. Which is 30psi less then what the book suggest "minimum" pressure should be. though cost wise would not be terrible idea to go ahead and repair. A trip to the pull a part for valves and a head-gasket from the store. certainly no more then $80.

vs

taking the time to source a used engine which has good compression and from a seller that i feel i can trust not to lie to me about mileage and general health of the long block assembly