Unsolvable Dead #1 Cylinder...

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spank044
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TheRealNap0le0n wrote:I'm a mechanic by profession actually.... and how was anything i posted stupid. especially since i was the first one to tell him to do a compression test.....
Because you read it before some else doesn't matter, but if we all read it at the same time and you were the first to do so then it would matter. The fact of the matter is just by going what he said in his first post any good tech would know that it is not a fuel or spark issue and it is only effecting the #1 cylinder. So from what we know from just that one post is he has no compression in the #1 cylinder. Since the rest of the cylinders are firing that means that he must have a bent valve in his #1 cylinder on the exhaust side. If it was intake then he would also have the number 2 intake bent, but since the number 2 cylinder runs that means it is a number 1 exhaust.
TheRealNap0le0n wrote:stupid question but did you line up the piston rings on cylinder one? cam timing wouldnt cause one cylinder to be dead. maybe it would cause the whole motor to be low but not like i see it.
This is the question that put you on my list. Even if the rings were in upside, lined up, or not even in the motor would still have some compression. You also said cam timing wouldn't cause this. Actually it can since it is a zero clearance engine and bad cam timing will cause valve to piston contact and bend the valve.

How much was taken off your head to achieve 210psi? Did you make adjustable cam gears to compensate for the timing?


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TheRealNap0le0n
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I don't know how much was milled, I didn't put this motor together I got it in a trade with a friend. No adjustable cam gears. And if the fuel rail was like I had in my mind fuel enters the rear near cyl 4 and progresses linearly to cyl 1. I had a lapse of memory how the fuel rail runs on this motor.

And for the record back in school we were building 350 motors and we had a group install the rings lined up and had 0 compression on the cylinder, it is possible

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LoserCard
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Dang this thread exploded with responses.

Anyways, I am in the process of pulling my head to zero down on the problem, which will most likely turn out to be valves.

Oh and btw, my timing has been perfect since I rebuilt it and checked it the 5 additional times after.

What I am thinking is a valve must have gotten stuck or something and hit the piston. So I am in the process of discovering that.

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spank044
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Get the head off yet?
TheRealNap0le0n wrote:And for the record back in school we were building 350 motors and we had a group install the rings lined up and had 0 compression on the cylinder, it is possible
The reason it had zero compression wasn't because of the rings, its because it was a Chevy. Also fuel enters in the front and travels to the rear.

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Still working on it. I work on weekends so might have it off by tomorrow or sometime during the week.

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LoserCard
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Success yo!

Ok the head is off and 1 exhaust valve on the #1 cylinder is bend. So now I have to get that changed out.

BTW do you guys recommend that I replace all of the valves or just get that one replaced? And should I get a valve job while I am at it?

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TheRealNap0le0n
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If you can afford it a valve job at the minimum, and have all the valves checked for straightness

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spank044
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How many of the pistons have little dents form the exhaust valves? How deep are the dents on the the number one piston?

rioredstang
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Take it to a good machine shop and let them inspect the head and advise you what is needed to repair head. I would do a valve job, resurface head.

OK, now I have a question for you. How do the valve get bent? Come on now, the truth. Over rev'ed, missed gear, come tell us now.

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I believe some moisture somehow got in the one exhaust lifter cap and it probably made that valve stuck down and piston hit it. Timing was perfect though. and only one exhaust is bent, not both. The valve was only bend about 1mm so it wasn't a hard hit.

Piston has very minor marks, only noticeable running your nail on top of the piston. It will be fine.

I am probably going to have the machine shop replace the valve and check all others for their seal and straightness, change stem seals, and maybe check spring pressure.

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spank044
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Did you have new guides put in recently. When you rebuilt the engine did you cut the head?

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I didn't change anything with the head, I figured it ran fine before I took it off. I was just inspecting piston rings and bearing, and replacing if necessary.

Head cut? As in resurfaced? Nope I checked for flatness and it was flatter than spec, so I left as is.

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Alright guys, I decided last night to buy a remanufactured head along with a new HG and ARP Bolts because I don't have the time to fix my head and I need my daily driver back. I can't keep using my gf's car. So I will report back in when I get that put back in.

Anything I need to know about remanufactured heads? Like maybe a break-in or anything, or do I just install hope for the best.

sommmatt
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99% of people in this thread are retarded.

Just install the head. Do the timing right. And drive it.

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Sounds good to me. I will be so glad to have my car up and running again. Tired of borrowing my GF's 07 Mustang... feels like a submarine, drives like a brick.

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spank044
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How much are you paying for a reconditioned head that is cheaper than getting yours fixed if it only had one bent valve. Something doesn't seem right about this thread anymore. One new valve and a valve seat cut costs less than $30 at the shop I go to and he has a one day turn around.

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Local shops here charge around $180 for a valve job, probably somewhere around $30-$50 to replace the valve.

I paid $260 shipped for a remanufactured head plus no core return. Remanned head came with new seals, resurfaced head, leak tested, pressure tested, ported, 3 angle valve job, and a 3 month warranty.

I can probably fix the old head myself and resell or keep for upgrading purposes. So I don't think it was a bad deal.

And what do you mean something doesn't seem right about this thread anymore. It is slipping to the path of the dark side?

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spank044
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LoserCard wrote:And what do you mean something doesn't seem right about this thread anymore. It is slipping to the path of the dark side?
That sucks that simple machine work in your area costs that much. After knowing what it would have cost to what you payed, I agree that you got a good deal.


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