How can I tell a 300 froma 240???
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From: Huntsville
How can I tell a 300 froma 240???
I just got a 73 f100 with a "300" I6 but I was wanting to make sure it is a 300 and not a 240. A freind was tellign me that it is the same block...
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From: The Big, Oregon
How can I tell a 300 froma 240???
Check the vin code- a 240 would be an A code, and the 300 would be a B code. A 240 isn't such a bad thing, as they will rev out further than a 300, and all the same performance tricks for a 300 will work.
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From: Huntsville
How can I tell a 300 froma 240???
SO it is the same block?
How do I know from he engine itself???
IIRC, the 3rd digit was an A...
It mayhave been replaced in th past?
The lady that I bought it from said that she was told it was a 300 I6....
If I were to rebuild it, could I use a rebuild kit for a 300????
I stil plan to do a compression test this evening to see what it looks like... it probably needs rebuilding.
Thanks you
How do I know from he engine itself???
IIRC, the 3rd digit was an A...
It mayhave been replaced in th past?
The lady that I bought it from said that she was told it was a 300 I6....
If I were to rebuild it, could I use a rebuild kit for a 300????
I stil plan to do a compression test this evening to see what it looks like... it probably needs rebuilding.
Thanks you
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How can I tell a 300 froma 240???
I don't think that 300's were used in light trucks until '74. If it's the original engine and you found the vin A, then I'd start thinking you have a 240. There is not much from the exterior of the motor that will tell you if it is a 240 or not. I've seen some 240 with balancers that have the crank nut sticking out rather than recessed, but then again I've seen 240's with the same exact balancer too. If you can find the emission calibration label (white one) on the valve cover and you read 51D , 52C, or 52F in the upper right hand corner - you have a 240...at least a 240's valve cover. If you really want to know for certain there are two methods - pull the head and measure the stroke. A 300's stroke is 3.98" while the 240 is somewere around 3.3 if memory serves correctly - key is if it's shorter than 3.98 you've got a 240. Pulling the head can be a real bear. Another route to take would be to pull the oil pan and check the casting number on the crank. If you find a 1L of 1LA on one of the center counter weights (along the OD), you're got yourself a 240. Lastly, trust your instincts. Good luck!
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From: Huntsville
How can I tell a 300 froma 240???
Well it is an A, just called the wife to recheck.
But you say it isn't "bad" to have a 240?
On a rebuild, could I use a 300 rebuild kit then, or are their other intricate details that would cause problems?
There is no label on the valve cover...
Thank you sir!
But you say it isn't "bad" to have a 240?
On a rebuild, could I use a 300 rebuild kit then, or are their other intricate details that would cause problems?
There is no label on the valve cover...
Thank you sir!
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Joined: Oct 2002
Posts: 18,488
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From: The Big, Oregon
How can I tell a 300 froma 240???
A ring and bearing kit for a 300-6 will work for the 240-6. They were the same block, but different rods, pistons, and crank. A performance cam for a 300 will also work, but I'd stay with a milder one. One way you can tell for sure, is to measure the stroke. If you are definitely going to rebuild it, just pull the head off and measure a piston at BDC. The stroke on a 300 is 3.98", while the 240 was 3.25", IIRC. You can also try checking with a piece of rubber hose or wire through the spark plug hole, but that isn't as accurate.
