My Drivers Side Cylinder Head is off (help)

**TerribleTed** · 04-10-2010, 09:55 AM

So I tok my car in for a compression check due to me messing up on a downshift and screwing the pooch,,,they said cylinder number 1 had only 25 psi.

Now I got the head off expecting to see a bent valve,,,,but wit my drivers side head off all things seem to be seating fine,,,,at least with my own eyes.

So I wonder,,,is Cylinder number 1 on the drivers side all the way in the front near where the power steering pump is?

I was expecting to see that a valve was not seated, but so far the drivers side cylinder head valves all look seated and the springs all look good as do the pushrods,,,

So if on a visual the valves loook seated, count it be a lifter that I need to checl out,,,

Its saturday now as I get greasy....help please....

**c5z28** · 04-10-2010, 10:01 AM

Originally Posted by 5.0THIS

Driver's cylinder bank is 1-3-5-7, front to rear. Passenger's cylinder bank is 2-4-6-8, front to rear.

The valve might be bent ever so slightly unnoticeable to your eyes. It could have just been a pushrod but the head is off already. Could you take it back and get the head tested?

**Orcus79** · 04-10-2010, 10:01 AM

pop the valve cover off the passenger side and ahve look there, also pull all your push rods and roll them over a flat piece of glass or otehr dead straight surface to see if any are bent.

**TerribleTed** · 04-10-2010, 10:09 AM

So is cylinder number 1 on the drivers side in the front of the motor nearest the power steering pump?

Also.,,originally I had removed both valve covers,,,and remove the pushrods,,,found only one slightly bent on the passenger side cylinder head on cylinder closest to the front on the battery side area. I then replaced all pushrods,,,fired her up and still had issues,,,thats when I took her into a ls1 performace show,,,they did a comp check and said cylinder number 1 was at 25 psi,.,,,so they said a bent valve,,,

Since I see no bent valve,,,or can tell if a slight bend is there on the head I have off I shall take the clinder head into the place I had them do a comp check to see what they think,,,I wonde if they meant the other cylinder head,,,

So is cylinder number 1 on the drivers side in the front of the motor nearest the power steering pump?

**67CamaroRSSS** · 04-10-2010, 10:20 AM

Cylinder #1 is the furthest forward cylinder regardless of engine type in an inline configuration.

In other words, yes, on all Chevy "V" style engines aligned front to back, the left (drivers) side bank forward is cylinder #1.

Did you look at the piston in cylinder #1? Any crescent shaped impressions? If so then the valve kissed the top of the piston. You may not be able to see a bent valve stem on the head with the valve closed but any misalignment, no matter how small is going to result in the valve not closing properly which will allow the cylinder to leak down.

**TerribleTed** · 04-10-2010, 10:26 AM

So all pistons on my drivers side,,,show on each of them on the left side top of each piston a cresent shape from where the valve was tapping,,,
it looks like only the carbon black deposit has the cresent in it,,,and not the piston metal portions....all look the same as far as deposits,and that little cresent shape,,,

**67CamaroRSSS** · 04-10-2010, 10:41 AM

If you have a stock cam then this could have been caused by over revving the engine.

If this is the case then chalk it up to the learning curve.

In my years of racing (since the 70's) I've acquired a couple of shelves full of broken parts.

**TerribleTed** · 04-10-2010, 10:47 AM

I know what caused by intitial problems,,
springs not being new and being old and tired,,,and me downshifting to many gears,,,,,

My posting did not ask what caused the damage,,,just identifying it,,,

**garygnu65** · 04-10-2010, 02:56 PM

point the intake runner up on the head,pour some solvent down the ports, see if the valves leak any fluid you poured in.you mite have bad piston rings .check the the cylinder bore to see if you can see any honing marks.how many miles on the motor?

**67CamaroRSSS** · 04-10-2010, 03:32 PM

Originally Posted by garygnu65

point the intake runner up on the head,pour some solvent down the ports, see if the valves leak any fluid you poured in.you mite have bad piston rings .check the the cylinder bore to see if you can see any honing marks.how many miles on the motor?

The "solvent down the intake port" is a good idea. It's what I use to CC combustion chambers with.

Well, that and a burette...

Might want to add some food dye as a colorant so it's easier to see.

**MeGoFast** · 04-11-2010, 05:26 AM

Originally Posted by TerribleTed

So all pistons on my drivers side,,,show on each of them on the left side top of each piston a cresent shape from where the valve was tapping,,,
it looks like only the carbon black deposit has the cresent in it,,,and not the piston metal portions....all look the same as far as deposits,and that little cresent shape,,,

I noticed the identical cresents on all 8 of my pistons when I removed my stock heads for an upgrade, I wouldnt sweat the cresents much since my engine was running fine.
I think the heads are interchangable from side to side, you could probably flip them and see where the drop in pressure follows. It may be time for a Head upgrade.

On a side note, I still have my original removed heads which had 107k miles on them. I may part with them to help out a fellow LS1'er for little if you really are in need.

Good Luck.

**TerribleTed** · 04-11-2010, 06:17 AM

So here is what I found,,and before I read all the new posts,,

I use my garden hose,,,and cleaned out my heads with some safe soap and water,,,while I did this,,when I filled the intake port for cylinder 1 i noticed some small amount of water leak out of the small valve.

If this is the cause of all my problems,,damn,,,I would never have thought that this little leak would cause a tech to measure only 25 psi when he checked the compression,,,

All other intake runners when filled with water did not leak out,.just the one..and so there fore it seems I have a leaking valve for cylinder 1 found,,

So am I to understand that the large valve with all the black carbon deposit on it is the intake valve and the small one that has not as much carbon on it the exhaust valve?

anyway...its time to remove the other cylinder head,,,,I thinks me is gonna do a total replacement of the valves, springs,,etc,,,,I only hope that when I remove this one leaky valve which seems to be seated visually just fine that I dont have any cracks in the valve seats,,,I jsut wanna get my baby back online,

**c5z28** · 04-11-2010, 05:47 PM

How much is it going to cost there are some stock heads for $150 on norcal-lsx.com. Nobody ever wants stock heads so I am more than sure you can get them for $100
Don't know if you are Norcal, cencal, or socal.
Here is the link
http://www.norcal-lsx.com/forum/showthread.php?t=71606

And yes the large valve is the intake and the small one is the exhaust valve

**TerribleTed** · 04-12-2010, 05:20 AM

Thanks for the data,,,I am going to get rent a valve spring removal tool and remove the suspect valve and check out the seat area and valve areas that contact each other,,,
then go from it from there with repairs or replacements,,,

**TerribleTed** · 04-16-2010, 05:30 AM

Done,,,valve came off...I installed it into a drill and found it to wobble oh so slightly,,,
I replaced the valve with a new one from chevy, to see if it seals good,,,and walah,,,,is seals great now,,,

I used the data you all and a friend of mine gave me.,.and it was all so helpful...

Now I am at the cross roads,,,what to do next,,,

thanks all.,,.,,

**c5z28** · 04-16-2010, 10:48 AM

Aftermarket heads

although it kind of defeats the purpose of all that trouble you just went through

and a cam

**TerribleTed** · 04-16-2010, 11:56 AM

it was a learning experience,,,and as always I am thankfull,,.

But I do and shall burn in hell for my the only sin I am ashamed of,,,that being the messed up downshift that caused my baby to bleed like she did,,,