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Dented Pistons and Bent Valves

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iguanahotsauce

10+ Year Contributor
238
0
Dec 13, 2010
Vancouver, Washington
So I finally got the head off of my 1g after countless hours of work. I read instructions in both the haynes manual and chiltons manual and I also had to look through several tutorials since before I got this car I knew nothing about how to do any mechanical work on a car. Long story short I got the car after it had been sitting for several years because the fuel pump went out. Before I got it the timing belt ripped and so the previous owner who is a family friend had the had re-done, new pistons, new valves, etc. After I got it I fixed a few major boost leaks, replaced some small parts and it ran great. About a month later all of the sudden it had no power behind it. I would put the gas pedal to the floor and it would hardly move. It starts but idles really rough. I went through everything I could find and checked every little thing before deciding to pull off the head. I finally got it off today and I noticed that all four pistons have valve impressions on them. The first and the fourth only have two valve impressions on each of them and the second and third both have impressions from all four valves. The impressions don't look too bad so I'm trying to figure out if I can re use the pistons or if I need to get new ones. I flipped the head over and it looks like a few of the valves are bent a little bit but not badly, I will be able to get a better look once I get the intake manifold and exhaust manifold off, I also have a problem with a couple of bolts from the exhaust manifold breaking off when I was trying to get them out of the head and three out of the four bolts that connect the exhaust manifold to the turbo broke off as well which was causing me to have a major boost leak before I took the head off. Any suggestions on where to head next would be great. I love this car and want to get it running again but unfortunately I need to get it running so I can sell it :(

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It is common enough for the valves to hit the pistons, most just buff off the high spots and go on.

For the head, you need to fix or replace it as you see fit
 
It is common enough for the valves to hit the pistons, most just buff off the high spots and go on.

For the head, you need to fix or replace it as you see fit

What do you mean by fix it? I think I would rather do the work myself than replace it because I don't have a very large budget for this car. I was going to disassemble the head and clean it and then replace any bent valves. What else should I do to it before I put it back on the block?
 
That would be fixing the head, replacing the valves.

But normally when the valves bend in the stock guides, the guides crack and need replaced, when you replace the guides, the valve seats need to be cut.

VVVV That link in my sig, click on it
 
If you're talking about those gouges on the edge of the pistons, those are there from the factory. I see no evidence of valve contact
 
If you're talking about those gouges on the edge of the pistons, those are there from the factory. I see no evidence of valve contact

What you are calling gouges are the valve reliefs, the edge of the valve will hit inside the valve relief, thats what the shiny spots are
 
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