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Discussion Starter · #1 ·
89 bronco 5.0...............


so i went to change plugs this morning, i pulled out the first plug motorcraft p/n awsf 44p, took one of the plugs i just got at orilleys, motorcraft p/n asf 42c. i new they were different but i figured the p/n had changed sometime in the past. wouldnt you know it, the thing doesnt fit. so i call back up there to verify that the guy who sold them to me wasnt high, and the p/n was correct, so went to auto zone and got an auto lite plug p/n app 25, the replacement for the plug that i pulled out of the truck, same thing just doesnt fit. has anybody ever gone through this little scenario? the sticker on the air box says i need the motorcraft p/n asf 42c, but i doesnt fit. somebody please let me know what the hell is going on, was this motor switched to some other ford block?
 

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He was telling you to check it out because it has a list of good spark plugs to use and part numbers IIRC.
 

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Howdy howdy howdy!
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How does it not fit? Too big? More threads? Will it even screw into the block?
 

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Try it now!!
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cant until i get this plug situation figured out. if the plug dont fit cant use it.
Yea it has alot of information on plug types and what you should use...PLUS if you are changing your spark plugs, you are obviously doing a tuneup, and that writeup has a great track record of proving mileage results in the 2mpg range, plus better power.

Or you could ignore it and not take my advice.
 

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Discussion Starter · #7 ·
ok let me start over here, liltimmy was on the right path, they plugs iwas given, the same one sixlitre says to get dont fit. almost like the threads are to big, the hole for the plug is clean the threads are not messed up, or crossthreaded.
 

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my bko ate my money
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different heads maybe? look for a serial number somewhere on the heads maybe on the front, write it down and call ford to see if they have any idea as to what heads you got, thats all i can think of or your not puttin them in on an angle like they are
 

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penis
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Is it just the one plug or maore than one. I ran into this problem with my head and one plug was different. Found out the thread had been crossed threaded at one point and was drilled and retapped for a larger plug.
 

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Satyr of the Midwest
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Those are both 14mm thread plugs, so there shouldn't be a difference in the threads to prevent the new one from going in. I think you're going to have to find an inspection mirror and a flashlight, and take a closer look at the threads. Follow up with a thread chaser if needed.
 

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Those are both 14mm thread plugs, so there shouldn't be a difference in the threads to prevent the new one from going in. I think you're going to have to find an inspection mirror and a flashlight, and take a closer look at the threads. Follow up with a thread chaser if needed.

With a ShopVac and a small nozzle in very close proximity. No muy bueno dropping crap into the cylinder.................:smokin:
 

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did you try comparing the old spark plug to the new one? Do the threads line up when side by side? same diameter? you should visually be able to see any significant differance in the two.
 

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The AWSF spark plugs are used in the GT40 heads as well as the 1986 Mustang heads and also the Cobra heads.They are a longer reach plug.Get a set of AWSF42P,they will last longer than AWSF42C's(p=platinum,C=copper).
 

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I noticed the same thing when I swapped the engine in my '92. I put in the engine from an '87 LTD and tried the use the new plugs I bought for the truck, but they wouldn't fit. The '87 LTD heads needed a much longer threaded portion on the plug. They were much longer than the truck plugs.
 

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The AWSF spark plugs are used in the GT40 heads as well as the 1986 Mustang heads and also the Cobra heads.They are a longer reach plug.Get a set of AWSF42P,they will last longer than AWSF42C's(p=platinum,C=copper).
if you read sixlitre's tune-up write-up you would see that platinums are not neccesary in these motors and can actually be detrimental in the mileage and power department. Coppers are all that is needed by these motors. I know, I thought the same thing, but 300 people can't be wrong!
 
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