These pistons scare any of you guys??
- Thread starter co04cobra
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78f100
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By the pics just looks like they need some brakekleen on then.
Spatel23
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Hard to tell bc the pictures are really small but they look ok.
That being said, it kind of depends on what you plan to do with it as to whether or not they are "ok"
That being said, it kind of depends on what you plan to do with it as to whether or not they are "ok"
Chvyrkr
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Why'd you pull the heads?
Ignorance is bliss, if the compression is good then...
Ignorance is bliss, if the compression is good then...
I even tried to upload the bigger pics too. :doh:
IF I would use the motor it would be back in a stockish truck. Nothing for a HP build.
It was a 99 motor 170K on miles.
I did clean the cylinders out for the pics fairly well. All marks on the pistons aren't coming off with just brake kleen.
IF I would use the motor it would be back in a stockish truck. Nothing for a HP build.
It was a 99 motor 170K on miles.
I did clean the cylinders out for the pics fairly well. All marks on the pistons aren't coming off with just brake kleen.
POWER-STRUCK
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how bad is the ridge on the cyl walls?
Arisley
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It has had at least a chip on it.
If a motor tests good on compression, there is no way I am breaking that factory head gasket seal.
If a motor tests good on compression, there is no way I am breaking that factory head gasket seal.
Motor was setting on my shop floor. With supposed piston issues, but compression in "spec". Like I said I acquired the motor. Its one of those where 12 other shops have worked on it before deals.
I didn't have any good way to check compression myself out of truck, and I'm not about to waste my time putting it in another truck without knowing a little more about it myself.
Passenger side was suppose to be the one with issues. So I pulled the head and cleaned it up to take a look. I didn't see anything that really "concerned" me. So I took a few pics and thought I would let some guys that rebuild them more often have a look.
Like the rest of you Im not in the habitat of pulling off a 7.3 head for no reason.
I didn't have any good way to check compression myself out of truck, and I'm not about to waste my time putting it in another truck without knowing a little more about it myself.
Passenger side was suppose to be the one with issues. So I pulled the head and cleaned it up to take a look. I didn't see anything that really "concerned" me. So I took a few pics and thought I would let some guys that rebuild them more often have a look.
Like the rest of you Im not in the habitat of pulling off a 7.3 head for no reason.
Hotrodtractor
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If compression was in spec.... why would someone believe it had a piston issue? Did you check the compression personally? Or is this something one of those other 12 shops before you told the person you bought the motor off of? What is in "spec"?
Charles
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Holy timing batman, lol.
Btw, if you can do a compression test in truck, why can't you bolt an automatic trans adapter plate to the motor with a starter and do the same test on the floor?
If the bowl exit isn't cracked up from heat, then I wouldn't worry too much about the pistons themselves from a little early injection all over the faces.
I would want to know the power level that engine was at with that kind of timing. That could help decide if the rods/block are likely fractured.
That's a butt-load of timing unless something changed with physics last night.
Btw, if you can do a compression test in truck, why can't you bolt an automatic trans adapter plate to the motor with a starter and do the same test on the floor?
If the bowl exit isn't cracked up from heat, then I wouldn't worry too much about the pistons themselves from a little early injection all over the faces.
I would want to know the power level that engine was at with that kind of timing. That could help decide if the rods/block are likely fractured.
That's a butt-load of timing unless something changed with physics last night.
20007.3L
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Thos pistons look pine, how do the cylinder walls look? and deep scoaring?
What are these said 'piston issues'? That comment is either a guess or with knowledge-- but worrisome nonetheless. If the bowl is fine, cyl wall is fine, compression fine, is there an issue with wristpin or rod?
For as far down as you have it now, I'd make sure--pull the caps and look at the whole piston.
An education question; what is showing itself as extra timing ?
For as far down as you have it now, I'd make sure--pull the caps and look at the whole piston.
An education question; what is showing itself as extra timing ?
Arisley
Moderator
The star shape burn marks in the tops of the pistons.
I didn't run the compression. I was told it was 340-360. I just got this motor with a truck. I was just buying the truck I didn't care about the motor. I just listened to the story, the guy wanted a little extra for the motor, and for what he wanted the core stuff was worth it.
It has set on my shop floor for 3wks. I had about 1/2 hour one evening while I was waiting on a customer, and I decided to pull that head off. I need to move the motor over to my storage building and anything I wanted to check needed done before moving.
I really do need to set up a test stand in the shop. I however really dont have room for it. The truck from what I could tell had a old gold superchips on the computer the rest of the truck was bone stock. I can not see any bad scoring or marks on the cylinder walls. I ran my bore scope in before I pulled the head, but I really couldn't tell anything that way.
On edit: I was a little surprised to see this much of a star patteren with just the old gold superchips. I have pulled a few of those off trucks, but never ran one in a truck. That was one reason for the thread.
It has set on my shop floor for 3wks. I had about 1/2 hour one evening while I was waiting on a customer, and I decided to pull that head off. I need to move the motor over to my storage building and anything I wanted to check needed done before moving.
I really do need to set up a test stand in the shop. I however really dont have room for it. The truck from what I could tell had a old gold superchips on the computer the rest of the truck was bone stock. I can not see any bad scoring or marks on the cylinder walls. I ran my bore scope in before I pulled the head, but I really couldn't tell anything that way.
On edit: I was a little surprised to see this much of a star patteren with just the old gold superchips. I have pulled a few of those off trucks, but never ran one in a truck. That was one reason for the thread.
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Charles
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I wouldn't build a special stand for compression. You can have the motor on a standard engine stand, or laying on an old tire for that matter and do a compression test with an auto plate and starter as long as you've already got all the actual compression test equipment.
Now, for hot retorques, a stand with a radiator and all is super nice. If you went that far I would say build the stand to engine dyno specs so it could be taken directly to the dyno if you needed to make some pulls.
Now, for hot retorques, a stand with a radiator and all is super nice. If you went that far I would say build the stand to engine dyno specs so it could be taken directly to the dyno if you needed to make some pulls.
Thanks but most pistons that Ive seen pics of have that pattern. Does later timing show more as just black? Sorry for detour.. carry on
Charles
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Unless you're turning mucho rpm... the fuel spray will not really need to get much outside the bowl. Last time I held my pistons in my hand I only had a half inch at the worst point outside the bowl on the long spray side. The other side was inside, or just over the lip. And I know my timing was between 35 and 40 degrees or so on those pistons.
To spray all the way across the face and into the wall, the timing is probably 50+ degrees easy if I were to make a guess.
Fwiw, the first time I broke 600rwhp I pulled 635 at 28 degrees max (scoped). 50+ is a lot unless you're making power at 4000 or so IMO. With timing comes power, and stress. The stress increases far faster than the power does though.
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couple of pics from last august @345k
140k with a gold superchip, 90k with DP tunes(never had a 80E tune) stock injectors and 200/30's.
200/238 -200's to date @ 356k, tunes from Cale.
With the exception of the valve to piston contact on #7, there was 1 other with a slight crack on the bowl lip
140k with a gold superchip, 90k with DP tunes(never had a 80E tune) stock injectors and 200/30's.
200/238 -200's to date @ 356k, tunes from Cale.
With the exception of the valve to piston contact on #7, there was 1 other with a slight crack on the bowl lip
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Wow that is quite a difference from my motor. Esp. since it also ran a gold superchip.
Im thinking when I get time. Ill clean it up and put a HG on that side. Check compression on the floor, and if it seems descent probably put it in a obs truck I just bought for myself that I'm fairly sure is going to need a motor.
@ Charles building a stand to run to operating temp is what I always had in my mind. At the moment though I don't have the time or room to set that up. Would be great tool to have in the future though. :ford:
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