Those plugs tell you all you need to know about where all the oil was going. Haven't heard about any HG's going in these years, maybe it got wet during dis-assembly, or maybe you have really good instincts catching a HG just before it failed. Keep the pics coming, lets see those oil returns!
Actually no. Well, the outside perimeter of the valve gasket was good and dry. There was a little bit of leakage to the plugs though, but not much. I had actually changed it myself last year thinking that it might be a source of the leaks. But, the previous gasket was clean, too. Unless you mean the spark plug tips were sitting in oil in the chamber. That might be true I guess.
Come to think of it, it's possible that some of the oil got on there when I was trying to pull it off. The little bolt inside the timing cover was hanging on and I didn't realize it for a while. So, it did get wiggle around for half and hour before I figure out what was hanging on to it. However, there has always been LOTS of oil leaking behind cylinder #1 forever. The power steering pump is caked with old oil. I'll get some pics of that, too.
So, do you guys think I'll have to replace all the valves, or just the exhaust ones?
HG = Head Gasket
If it were me I wouldn't replace any of the valves. I would just remove them and clean them up nice. They don't look damaged, just lots of build up. When they are out, replace the valve seals too. The exhaust valve seals will have hardend pretty good with the heat from the exhaust valves.
If you have had an oil leak for a long time you will definitely want to fix that while you have it apart. The first thing I'd look at would be the timing chain tensioner. It's possible the timing cover is leaking as well.
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'98 Prizm 4spd 297K bought @ 221K for $300 Oil consumption fixed @ 265K for $250ish
'99 Prizm 3spd sold to brother Jan. 2012 currently at 330K
If it were me I wouldn't replace any of the valves. I would just remove them and clean them up nice. They don't look damaged, just lots of build up. When they are out, replace the valve seals too. The exhaust valve seals will have hardend pretty good with the heat from the exhaust valves.
If you have had an oil leak for a long time you will definitely want to fix that while you have it apart. The first thing I'd look at would be the timing chain tensioner. It's possible the timing cover is leaking as well.
HG is head gasket, of course. haha. Yeh, I'm starting to think I'm in deep here and will have to pull the timing cover. I didn't really want to get into that, but at this point I guess I have not choice. Everything on the front of the engine underneath the drive belt is soaked with oil. I haven't studied up on pulling all that stuff out, yet. I gotta hit the manual today.
I'm happy you think I can save the valves. That'll save me some decent dough.
Got the pistons out. Did a little water test by turning them upside down and pouring some water in them. Guess what? Almost all oil return holes are NOT clogged. There was only one hole completely clogged on piston 1. I also discovered that the oil control valve is cracked apart and busted. I really need everyone's help on this. I have no idea how that could have been effecting the performance of the engine. I took pics of the upper rod bearings and also close ups around the timing chain cover/head gasket mating areas as there is a lot of oil there.
I have a few questions:
1) Could the engine still have been burning oil even if the oil holes were not clogged?
2)Would worn out pistons alone account for this?
3)Also, is there any way to tell if the old rings were worn out by looking at them? Unfortunately, I didn't get pics of them before taking the old rings off.
Got the pistons out. Did a little water test by turning them upside down and pouring some water in them. Guess what? Almost all oil return holes are NOT clogged. There was only one hole completely clogged on piston 1. I also discovered that the oil control valve is cracked apart and busted. I really need everyone's help on this. I have no idea how that could have been effecting the performance of the engine. I took pics of the upper rod bearings and also close ups around the timing chain cover/head gasket mating areas as there is a lot of oil there.
I have a few questions:
1) Could the engine still have been burning oil even if the oil holes were not clogged?
2)Would worn out pistons alone account for this?
3)Also, is there any way to tell if the old rings were worn out by looking at them? Unfortunately, I didn't get pics of them before taking the old rings off.
1) YES! It was very clear from the pictures of the head and spark plugs that it was burning oil. Just because the holes are not all 100% clogged does not mean it's not burning oil. My first Prizm was burning a qt. every 100 miles right at the end before I fixed it but my current one was only at a qt. every 500 miles or so. If the holes are 50% clogged that's a major issue. Heck, if they are any % clogged that's an issue. You probably won't find 2 of these things exactly the same on tear down but if the are buring oil....you know what needs to be done.
2) Technically the piston skirts do make contact with the cylinder walls but I would mostly call the piston a non-contact part that doesn't WEAR out. In a typical rebuild you replace them because they do have a life expectency and will get weaker over time. I don't think they have anything to do with your problems.
3) I don't think I've run in to worn out rings on these cars. They last a very long time. When I replace them it's not because of wear so much as the fact that if you remove the piston and the old rings from it, you should install new rings and hone the cylinders. Obviously you have to remove them to fix the oil burning problem so you just install new ones.
4) bearings look GREAT!
5) I'm taking a guess at this, did you leave the oil control valve in when you removed the head bolts? If so, that's when it broke. You cannot remove the head bolt without breaking it. You have to remove it first. I think I've got an extra (used) one on hand I'd sell you for cheap if you are interested.
6) It definitely looks like you were leaking a lot of oil. You may want to take the timing cover off and reseal it. I really like to skip this step because it is a pain (and completely unnessesary) normally but in your case you may need to. You just get in to a bunch of other stuff like removing the water pump and deciding if you want to then install a new water pump (may as well at that point).
7) Now is the time that you may start to feel overwhelmed. But don't!! Just take your time. You get to fix this thing right. You will love it when you are done. Keep the pics coming!
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'98 Prizm 4spd 297K bought @ 221K for $300 Oil consumption fixed @ 265K for $250ish
'99 Prizm 3spd sold to brother Jan. 2012 currently at 330K
First of all Bennie, let me say thanks once again. I can't tell you how invaluable it is to have someone experienced help me through this process.
Now, let me correct something. In question #2 I meant to ask if worn out "piston rings" could have caused the oil burning. Nontheless, I think you address those issues fully.
I did leave the oil control valve in when I pulled the bolts. So, if what you're saying is right, it was never broken before. Hmm...ok. In my mind I really want to understand fully why the engine ran like crap. Remember, too, that it lost significant power and hissed loudly just before this rebuild. Clogged cat again? Anyway, I have no choice but to rebuild it as I can't afford a new engine. Btw, thanks for the offer on the control valve, but I just ordered one from Rock Auto last night.
Yeh, I think I'll have to pull the timing cover. Let me ask you this: Haynes Manual say to pull the power steering pump, engine mount, windshield washer reservoir, crankshaft position censor, belt tensioner.....EVERYTHING! Are there any shortcuts to this or do I have to do ALL of it?
First of all Bennie, let me say thanks once again. I can't tell you how invaluable it is to have someone experienced help me through this process.
Yeh, I think I'll have to pull the timing cover. Let me ask you this: Haynes Manual say to pull the power steering pump, engine mount, windshield washer reservoir, crankshaft position censor, belt tensioner.....EVERYTHING! Are there any shortcuts to this or do I have to do ALL of it?
Glad to help!
You do need to pull everything. It's been about 5 years since I had the timing cover off one of these and I forgot what a pain it was. It's not that it's really that hard, it's just that you need to remove a lot of stuff you would think you wouldn't have to. The power steering pump doesn't actually have to be pulled out of there and you don't have to disconnect the hoses, you just have to unbolt it because the mounting bolts go through the timing cover. Limited space is what makes it hard, nothing else.
It sounds like you will have other issues to work out when you get it back together too. If it ran great, but just burned oil, you would be good to go, but it sounds like you may have to mess with the cat and possibly replace the upsream O2 sensor as well. They both get taken out by excessive oil consumption.
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'98 Prizm 4spd 297K bought @ 221K for $300 Oil consumption fixed @ 265K for $250ish
'99 Prizm 3spd sold to brother Jan. 2012 currently at 330K
I think have a situation here. I've started taken everything off the front of the engine to re-seal the timing chain cover and any other gaskets on the front. But, the pistons are still out and I have to get the harmonic balancer bolt off. I don't have an impact wrench and can't afford one now. I've been looking around the net and don't see a way out of this one. It seems I either have to put the engine back together first, loosen the bolt, and then take everything off again. Or....well, there is no "or." I can't do the breaker bar trick either. Any suggestions anyone? Thanks.
I think have a situation here. I've started taken everything off the front of the engine to re-seal the timing chain cover and any other gaskets on the front. But, the pistons are still out and I have to get the harmonic balancer bolt off. I don't have an impact wrench and can't afford one now. I've been looking around the net and don't see a way out of this one. It seems I either have to put the engine back together first, loosen the bolt, and then take everything off again. Or....well, there is no "or." I can't do the breaker bar trick either. Any suggestions anyone? Thanks.
You already have the oil pan off so you can use a small piece of wood to stop the crankshaft from rotating.
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'98 Prizm 4spd 297K bought @ 221K for $300 Oil consumption fixed @ 265K for $250ish
'99 Prizm 3spd sold to brother Jan. 2012 currently at 330K
Got the timing cover off. Thanks, Bennie, the wood trick worked great. The pulley just slid off by hand, too. It looks like there was a leak from the bottom front of the cover near the harmonic balancer sensor. Also, there doesn't seem to have been very much sealant around the cover. I could hardly see any in fact. It also looks suspect around the timing chain tensioner.
Had to order online a OTC valve spring compressor. I could not find one for sale in town ANYWHERE. It's a corolla! Why are these things so hard to find??
That's a good question! I can make a few quesses but I don't know for sure. Number 2 might be the thermostat. Something in there may be for the oil pump and oil pickup. Number 7 I think is for the VVT filter plug on the head. Make sure you remove and clean that! I think this gasket set may also include parts that are not needed for our application but it's cheaper for them to just add a couple extra gaskets to the set than have 2 or 3 different sets that are almost the same.
I always just use black high temp NAPA RTV.
You are right, you really don't see much sealant on anything. That's normal. You don't need a thick bead anywhere, just enough to seal it.
You definitely have some leaks going on there! It looks like you have a leaky crank seal for sure. You will just have to replace that and make sure everything else gets sealed good when you put it back together. Spend plenty of time cleaning / degreasing the whole timing conver. RTV will not stick / seal anything if it's oily.
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'98 Prizm 4spd 297K bought @ 221K for $300 Oil consumption fixed @ 265K for $250ish
'99 Prizm 3spd sold to brother Jan. 2012 currently at 330K
That's a good question! I can make a few quesses but I don't know for sure. Number 2 might be the thermostat. Something in there may be for the oil pump and oil pickup. Number 7 I think is for the VVT filter plug on the head. Make sure you remove and clean that! I think this gasket set may also include parts that are not needed for our application but it's cheaper for them to just add a couple extra gaskets to the set than have 2 or 3 different sets that are almost the same.
I always just use black high temp NAPA RTV.
You are right, you really don't see much sealant on anything. That's normal. You don't need a thick bead anywhere, just enough to seal it.
You definitely have some leaks going on there! It looks like you have a leaky crank seal for sure. You will just have to replace that and make sure everything else gets sealed good when you put it back together. Spend plenty of time cleaning / degreasing the whole timing conver. RTV will not stick / seal anything if it's oily.
Thanks Bennie. When you say "crank case" do you mean just the timing chain cover? Also, while I've got that thing off what should I definitely replace or check on? I just don't ever have to take it off again.
I checked the piston ring gap and it's right on the money. Drilled oil holes today and am gonna hone tomorrow and get those suckers in. Won't have the valve spring compressor for a few days so have to wait on valve work. Here's pic of the new oil holes.
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currently at 330K
haha. Yeh, I'm starting to think I'm in deep here and will have to pull the timing cover. I didn't really want to get into that, but at this point I guess I have not choice. Everything on the front of the engine underneath the drive belt is soaked with oil. I haven't studied up on pulling all that stuff out, yet. I gotta hit the manual today. 
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