i found a late 86 early 87 f250 reg cab 2wd for $1000. im debating on buying it for a "build" project. i havnt went an looked at it yet and he wasnt sure if it had a 6.9 or 7.3. is there any way to look at the motor itself and tell the difference? thanks!
how to tell the difference between a 6.9 and 7.3??
- Thread starter 93f250idi
- Start date
icanfixall
Official GMM hand model
Really the only true way to know is the head bolt hex size. A 6.9 is 7/16 wrench size as is the bolt diamtert. The 7.3 is a 1/2 inch hex size and the bolt is 1/2 inch diameter. The block serial number found just to the drivers side of the injection pump gear cover will state either 6.9 or 7.3 in the series of numbers. I think the 7.3 motors started at serial number 500,079 and went up to 116,330. A turbo 7.3 block started at 116,331 and up from there.
what numbers are the 6.9?
