C5 ls1 engine problem question !!!!
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C5 ls1 engine problem question !!!! Alright guys I have a blown head gasket on my ls1 it has around 97k miles now I took it to a mechanic and he told me that if he was to change that gasket(and bolts) I don't have a 100% assurance that it will seal up perfect because of the aluminum block being heated over all these years and advices me to go buy an iron block. Is this at all true or good advice ? is it better for me to grab an iron block for further problems? I need input guys it's my DD and I need it fixed.
If I went with the iron block lq4 how easy would be my swap? of course I would cam it, swap heads and a few other things here and there while the engine is out
Thanks in advance!
If I went with the iron block lq4 how easy would be my swap? of course I would cam it, swap heads and a few other things here and there while the engine is out
Thanks in advance!
Alright guys I have a blown head gasket on my ls1 it has around 97k miles now I took it to a mechanic and he told me that if he was to change that gasket(and bolts) I don't have a 100% assurance that it will seal up perfect because of the aluminum block being heated over all these years and advices me to go buy an iron block. Is this at all true or good advice ? is it better for me to grab an iron block for further problems? I need input guys it's my DD and I need it fixed.
If I went with the iron block lq4 how easy would be my swap? of course I would cam it, swap heads and a few other things here and there while the engine is out
Thanks in advance!
If I went with the iron block lq4 how easy would be my swap? of course I would cam it, swap heads and a few other things here and there while the engine is out
Thanks in advance!
Last edited by celtsean; Mar 4, 2015 at 04:10 PM.
Sounds like a bunch of **** to me. I work at a gm dealership and have done numerous aluminum ls engine jobs without any hesitation due to the block material. Unles you overheated the engine I wouldn't worry about just replacing the gasket.
That's a load of horse ****. Yes, if the cylinder head gets too hot it can warp, and if the engine itself gets too hot the deck can warp. However the cylinder head will go long before the deck, and if the cylinder head is warped you can just take it to a machine shop and (provided it's not too badly warped) machine it flat again.
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And as far as over hearing it ..it has over heated one time where I had to turn it off but idk if one time may cause it to warp and if the heads are damaged I'm going to buy the 243's my only concern is my block. I'm taking it to the Gm dealership soon and see what they tell me and the repair shop but thank you guys for assuring me it is indeed bullshit because that's what I was thinking from the get go
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Thats a load of bull sh**. The head gasket is there to fill the void between the head and block. If you are really worried about it sealing have a machine shop check your head and machine it to get it totally flat. Even that is only necessary if you over heated your engine severely and warped your head. Aluminum is porous by nature, but much to small for any oil/coolant to come out, unless you have a structural fault in the metal. I would just make sure you buy a quality brand gasket and torque it to the right spec. A quick way to check your engine block and head is get a straight edge metal ruler or something and lay it over it, if you see a noticeable gap, or high/low spot take it to an engine builder/machinist for further investigation(very unlikely).
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Yes, you will always want to check the head surface as aluminum heads frequently will warp when overheated and need to be surfaced.
A problem with block warpage would be rare, but you can check the deck surface for true with a straight edge and feeler gauge (.003 or something like that).
A problem with block warpage would be rare, but you can check the deck surface for true with a straight edge and feeler gauge (.003 or something like that).
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Yes, you will always want to check the head surface as aluminum heads frequently will warp when overheated and need to be surfaced.
A problem with block warpage would be rare, but you can check the deck surface for true with a straight edge and feeler gauge (.003 or something like that).
A problem with block warpage would be rare, but you can check the deck surface for true with a straight edge and feeler gauge (.003 or something like that).
Well what probably happened was the gasket let go, and caused a drop in pressure in the coolant system. Remember that for every psi of pressure the boiling point of water increases by 3 degrees. So if you lose pressure you'll run into overheating problems.
Honestly, I highly doubt it's cheaper to out a replacement engine in. Most ls1s on eBay run like 3-4k. Those that don't are questionable. You could buy a set of 243 heads with springs and valves for far less. I think tsp has a ported set on their website for like 1500?
And again, deck warpage would be an extreme overheat, like steam billowing out of the hood extreme.
Imho I would change the heads myself. They aren't particularly hard to get to on the corvette, and it's a good learning opportunity. Plus noting can beat the satisfaction of fixing your own car
Honestly, I highly doubt it's cheaper to out a replacement engine in. Most ls1s on eBay run like 3-4k. Those that don't are questionable. You could buy a set of 243 heads with springs and valves for far less. I think tsp has a ported set on their website for like 1500?
And again, deck warpage would be an extreme overheat, like steam billowing out of the hood extreme.
Imho I would change the heads myself. They aren't particularly hard to get to on the corvette, and it's a good learning opportunity. Plus noting can beat the satisfaction of fixing your own car
Well what probably happened was the gasket let go, and caused a drop in pressure in the coolant system. Remember that for every psi of pressure the boiling point of water increases by 3 degrees. So if you lose pressure you'll run into overheating problems.
Honestly, I highly doubt it's cheaper to out a replacement engine in. Most ls1s on eBay run like 3-4k. Those that don't are questionable. You could buy a set of 243 heads with springs and valves for far less. I think tsp has a ported set on their website for like 1500?
And again, deck warpage would be an extreme overheat, like steam billowing out of the hood extreme.
Imho I would change the heads myself. They aren't particularly hard to get to on the corvette, and it's a good learning opportunity. Plus noting can beat the satisfaction of fixing your own car
Honestly, I highly doubt it's cheaper to out a replacement engine in. Most ls1s on eBay run like 3-4k. Those that don't are questionable. You could buy a set of 243 heads with springs and valves for far less. I think tsp has a ported set on their website for like 1500?
And again, deck warpage would be an extreme overheat, like steam billowing out of the hood extreme.
Imho I would change the heads myself. They aren't particularly hard to get to on the corvette, and it's a good learning opportunity. Plus noting can beat the satisfaction of fixing your own car
Stock 243s are a compression bump and flow better so even for the $500-$600 or so would net you a running engine and an extra 30 HP.
Personally I would remove the heads, probably can be milled .010" since you didn't really overheat. Won't change compression that it would matter. Make sure the gasket didn't damage the block by burning it and check with a straight edge and not a ruler or that BS. A true straight edge can be purchased from most tool dealers.
While you have the heads removed, change the valve seals and check for wear, and should replace the lifters while you are in there if you are doing both.
While you have the heads removed, change the valve seals and check for wear, and should replace the lifters while you are in there if you are doing both.
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Until its taken apart and checked ANYTHING is possible. I have seen the deck on aluminum blocks warp bad enough that the block was not useable. So the mechanic is not lying to you. simple enough to check once the head is off.
He almost has a point (Op's repair shop) but that is SERIOUSLY over-analyzing like even I've never done before.. And I'm the insane ******* around here that reads into **** and analyzes way to much. (Recovering perfectionist)
There's no 100% sealed, but this guy just sounds really paranoid. it's a headgasket.... Do your best to clean it and make sure everything is straight and true and run the car. if you have a problem that relates back to the HG, then you can worry.
There's no 100% sealed, but this guy just sounds really paranoid. it's a headgasket.... Do your best to clean it and make sure everything is straight and true and run the car. if you have a problem that relates back to the HG, then you can worry.