6.9 & 7.3 IP's, interchangeable?

apextrans

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Hey fellas,

Been pretty busy with work lately, but things are slowing down for a while. I finally got the Sidewinder kit & am preparing to upgrade my fuel system before putting the turbo on. My question is twofold really. 1. will a 6.9 IP work on a 7.3? Are they interchangeable? This truck is my only means of transportation & can't be down for long periods of time. I don't think I have enough knowledge to rebuild the IP myself so I was considering finding a used IP to rebuild then swap over to save time.I can't seem to find a 7.3 IP but have seena few 6.9's on ebay. What's the right money for a used IP? 2. I don't have any service records for this truck & don't know if the injectors & IP have been addressed yet, but it was a Fire Dept. Quick Response Unit in it's past life. This truck runs GREAT even without a turbo. It only has a little over 90,000 on the ticker. A few friends of mine are mechanics, although not DIESEL mechanics & seem to agree that something has been done in the past or it would not run the way it does. Any suggestions? I don't want to waste time & money I don't have too.

Thanks,
Scott
 

argve

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Yes they will work either way.

Now if my memory serves the differences are in the piston size (diameter) in that the 6.9 has a (I think) a 17mm and the 7.3 has a 21mm piston. So the 7.3 has more potential in flowing more fuel over the 6.9 pump. You will notice right off the bat if both fuel screws are set to the factory setting that the 6.9 pump will have less power but it will still run down the road at 65+mph. Pumps are cheap in the grand scheme of things typically around 350 for a rebuild exchange pump so why not just do a swap. You can in most cases get one from a rebuilder then take it home do the swap and then take him back the core in the same day. Now if you go the online route most will ship you the replacement pump now then wait like 30 days before hitting your CC for the core. So you have plenty of time to get the core back to them.

Might be the best way to go. But if your just looking to be froggy and go through one completely then I can understand that as I like digging into things. Just take pictures and write an deal up on it as you go through. I for one would be interested in reading about it as I have only go as far as the delivery valve in the DB2 pumps which albeit that is actually as far as I really would want to go seeing as they aren't that expensive in exchange form.
 

apextrans

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Is there any way to tell by looking at the pump or injectors if they have been changed or rebuilt? I really am thinking this thing has been freshened already. How would I know for sure, aside from doing it myself?

Scott
 

Tristan

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Not sure on the IP, but are the injectors still Battleship Gray like the engine? If so they are probably original. My Stanadyne replacement injectors are black.
 

Agnem

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I run a 6.9 pump on the 7.3 powered Lady Moose. There is no concern with the 6.9 pump not being able to deliver enough fuel. It will melt a 7.3 just as sure as it will a 6.9. The think I think is neat, is that a turned up 6.9 pump will flow fuel longer (we're only talking about milliseconds here) than a 7.3 pump set to the same fuel delivery rate. What this means to me is that there is a chance that the burn is cleaner. In the grand scheme of things, It is my personal belief, that the only reason they changed pumps when they went to the 7.3, is because at the time (1986 ish) they went to market, they had invisioned improvements to the 7.3 that never materialized, but became the PSD instead.
 

FORDMAN41291

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1984 Ford F250 Freeze Plug?

Where is the freeze plug located on a 1984 Ford F250 6.9L Diesel? I think my truck needs a new one because I flushed my radiator and put everything back to normal hoses and all started to fill up with fresh new coolant, and on the 2 gallon I noticed a small leak (of coolant) under neath the truck near the oil filter so I removed the oil filter to get a better look and still could not see the origin of the leak and it was not oil, so my step dad said it might be a freeze plug because he said he had the same kind of problem on his Chevrolet 1500 and had to get it replaced.

here are some photos I took after the leak and halted temporarily. look beyond the oil filter near the engine block


also if someone could supply a repair or users manual I would appreciate it.

Thanks again
 
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Diesel JD

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Dude you should start your own thread for this thing. I was gonna say, its been awhile since Apextrans had an IDI. The freeze plugs are a funny thing on these motors, if it pops one you'll want a Ford original the aftermarket ones, some people have had serious problems with. Gary(icanfixall) has learned the hard way and fixed it right and is our resident expert on freeze plugs. If you are leaking coolant and have already fixed all the hoses/have tight connections, its probably a leaky head gasket. However in that neighborhood there's a chance it could be the oil cooler and also the block drain plug for the driver's side is not too far from there either.
 

FORDMAN41291

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I appreciate it, are these somewhat cheap simple fixes besides the head gasket thing, I know that from asking about my moms old car, sorry I did not start a new thread I am new to this forum and am not sure how to.

thanks
 

icanfixall

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To post a new thread look at the top of this section on the left side. You will see post a new thread. Click on that and go for it....:sly
 

FORDMAN41291

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I am definitely going to take Diesel JD's advice and check all the hoses and gaskets again, hopefully it's not a head gasket problem, how much do Oil Coolers cost, but hopefully its just the block drain plug, I am not all that good when I comes to automotive except for some electrical.
 

Diesel JD

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Oil cooler isn't too bad money wise, it'll cost you about $50-70 for all the parts (orings and gaskets) hopefully it has the newer 4 ring style bundle, not the obsolete 6 ring job. Those things are beginning to be a ****** to find parts for. I have a feeling though, its either a hose you failed to tighten enough or an external head gasket leak.
 

FORDMAN41291

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and uh no it's not a hose unfortunately, see the thing is the leak is not big it's small like when you run a faucet at almost a drip but it is still continuous. I will ask by buddy to also check the head gaskets can I get some of that stuff that plugs holes in radiators? will that help if its not the head gasket?

Thanks
 
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