How can you tell if you have a four bolt main block?
09-10-2004, 02:29 PM
#1
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How can you tell if you have a four bolt main block?
Here's the story, the previous owner of my car had the entire engine replaced after he sucked up some water in the intake. The new block has a date stamp on it (sticker) with a build date of September 2000. The engine was purchased through GM. I thought that I read somewhere that all LT1's replaced under warranty were four bolt main blocks, and it got me thinking if maybe mine could be as well.
So are there any external differences, or perhaps a code in the serial number on the block that would differentiate a four bolt block from the standard 2 bolt?
So are there any external differences, or perhaps a code in the serial number on the block that would differentiate a four bolt block from the standard 2 bolt?
09-10-2004, 04:01 PM
#2
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Location: Point Pleasant, NJ... USA
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Re: How can you tell if you have a four bolt main block?
No external method that I am aware of..
But yes all GM replacement LT1's were 4 bolt..
Only thing that comes to mind here [and I don't KNOW if it's even possible ] would be to remove the 'low oil ' sensor [see: http://shbox.com/1/low_oil_sensor.jpg
during the next oil change, and get a bore light, etc. to look into that hole.. you may get lucky and actually be able to SEE the 4 bolt main? Just a thought..
But yes all GM replacement LT1's were 4 bolt..
Only thing that comes to mind here [and I don't KNOW if it's even possible ] would be to remove the 'low oil ' sensor [see: http://shbox.com/1/low_oil_sensor.jpg
during the next oil change, and get a bore light, etc. to look into that hole.. you may get lucky and actually be able to SEE the 4 bolt main? Just a thought..
Last edited by Mtrhds94Z; 09-10-2004 at 04:03 PM.
09-14-2004, 10:30 AM
#4
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Re: How can you tell if you have a four bolt main block?
I have the same problem. Mine was replaced in 2001 at 37,041 miles. I have also heard the same thing, that all replacements are 4 bolt mains. I guess I'm going to have to pull the pan one of these days.
If you ever confirm this, let us know.
If you ever confirm this, let us know.
09-16-2004, 06:05 AM
#7
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Re: How can you tell if you have a four bolt main block?
I never heard of this.. Clue us in more on the #'s?
Far as I know there's no way to tell externally..w/o looking at the main caps.. [on lt1's that is..]
Far as I know there's no way to tell externally..w/o looking at the main caps.. [on lt1's that is..]
Re: How can you tell if you have a four bolt main block?
09-16-2004, 10:25 PM
#10
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Re: How can you tell if you have a four bolt main block?
Originally Posted by 38oldz
The only thing on the back of block reads 5.7L LT1.Nocasting# No id # on front pass side of block. 94 LTI suposed to be police eng. any help ?
09-17-2004, 07:52 PM
#11
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Re: How can you tell if you have a four bolt main block?
Still not sure about year, has vented opti.never removed it to see how it is driven. only hint is cast heads,vented opti. Have a part# of opti cap i think 1103916, is that any help?
09-17-2004, 09:48 PM
#13
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Re: How can you tell if you have a four bolt main block?
Originally Posted by 38oldz
Still not sure about year, has vented opti.never removed it to see how it is driven. only hint is cast heads,vented opti. Have a part# of opti cap i think 1103916, is that any help?If you want to determine the year of the engine (if from f-body) check here.
09-17-2004, 11:31 PM
#14
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Re: How can you tell if you have a four bolt main block?
Originally Posted by 38oldz
Still not sure about year, has vented opti.never removed it to see how it is driven. only hint is cast heads,vented opti. Have a part# of opti cap i think 1103916, is that any help?Is that a B body motor?
09-18-2004, 11:23 AM
#15
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Re: How can you tell if you have a four bolt main block?
all OEM F-bods had 2-bolt mains.
Only one I personally know of from working at the Pontiac dealer. Customers car had a 4 bolt block.. I know it was the original engine because I had worked on it since new, owner always took it to me for work. Bought the car with 4 miles on it.
I have heard one other tech I know at another local dealership that found a 4 bolt f-body from the factory.. wierd huh.