7700 and 7710 6600 question

[pt756]

Hello there, was talking to the local Ford dealer about a neighborhood 7700 for sale, open station 8k hours, I know the tractor was bought new, as he is a close neighbor, wants to sell it now, sold cows , and as it goes downsizing slowly, all these smaller tractors are great as when you have cows they are helpful in making hay, we have a 5600 that gets a lot of use, raking, tedding hay and so on, as I remember he had to replace the engine very early in its life, put a crat engine from a 7710 in, so dealer said that was a heavier built engine more webb ing on itm is it the 268? I thing our 5600 has a 256 in? then we have been looking, for a 6600 or 6610 with the dual power, what are their engine choices and advantages over the 5600 or 5610. our 5600 does not have dual power, I have always said it is like an old M farmall except better hydraulics and so on, doesnt seem like much to go wrong, so what kind of troubles with the dual power? have a lot of old IH, so I know all about the TAs, and the last question do all the Fords pto turn on and off the same way, ? seems kind of abrupt when you have a rotary rake on behind,thanks

 

[sotxbill]

Not an expert... but ironically its the xx10 series that is more likely to cavitate due to the higher injection pressures creating the subsonic sound waves... That travel through the block and cause the cavitation at a point where the soundwaves all add together. I never buy a xx10 series without checking the radiator for bubbles. Actually I never buy any tractor with out that check.. I have seen a large amount of the ford six cyls in the 10 series or tw series blow bubbles... and anything earlier its usually a head gasket... That being said, any tractor that grossly overheated will usually have a failure, even if its just a broken radiator hose.

 

[Sean in PA]

I remember he had to replace the engine very early in its life, put a crat engine from a 7710 in, so dealer said that was a heavier built engine more webbing on it is it the 268?

The external webbing on the block was introduced on all engines at some date, regardless of the displacement. I am not sure of the exact date, but I think it was sometime in the mid to late '80's, or the early '90's at the latest.

I thing our 5600 has a 256 in? then we have been looking, for a 6600 or 6610 with the dual power, what are their engine choices and advantages over the 5600 or 5610. our 5600 does not have dual power, I have always said it is like an old M farmall except better hydraulics and so on, doesnt seem like much to go wrong, so what kind of troubles with the dual power? have a lot of old IH, so I know all about the TAs,

I'm not sure what you are getting at. Are you looking for replacement engines or replacement tractors?

and the last question do all the Fords pto turn on and off the same way, ? seems kind of abrupt when you have a rotary rake on behind,thanks

The 5xxx through 7xxx PTO's were all independent and used the same basic design, but some changes were made over the years and some could be "feathered" easier than others.

 

[Bern]

Cavitation has nothing to do with injection pressures, and everything to do with cylinder wall vibrations. Ford eventually cured it in the Genesis series engines by making the water jackets shorter and anchoring them with internal tie bars.

 

[Bern]

PTO brake application is abrupt on all of them. It's just the way they are, and not much can be done about it.

PTO engagement is featherable with the 10 series, meaning if you move the engagement handle slow enough you should be able to engage the PTO to your liking.

 

[Destroked 450]

75-80 5600 used a 233 ci engine
75-80 6600/6700 used a 256 ci engine
75-80 7600/7700 used a 256 ci turbo engine
Blue Power Special models were introduced in 81 with the 4 cylinder models received engine upgrades
5600 upgraded to 256 ci
6600/6700 upgraded to 268 ci
7600/7700 upgraded to 268 turbo
Dual power was optional on all of the 4 cylinder models but was more common on the 7 series

The pto on our 5600 and 6600 have a pretty harsh engagement, our 6610 pto engages much smoother

 

[Matt in Oz]

Hi pt756

Had a 7700 that had been abused, put a 444t crate engine in it which was a very nice engine which started well when cold. Depending on the tractor if it has not been abused should be a good tractor. Mine had a cab which made any repair work more difficult. Be prepared to keep the idle up at 1000 rpm to oil the turbo and change the coolant regularly. With the PTO they are sudden and the brake band can let go meaning no stopping it. Best thing is to idle them down and then disengage the PTO. They are great hay tractors as the sequential gears make changing ground speed to match windrows for baling easy. Always wished Ford had a go at making a synchro 8 speed. Got a 40 series SL now and find the 7700 gears easier to select.

 

[sotxbill]

We will agree to disagree. As systems were improved, faster burn and more violent explosions occurred. The pressure waves/subsonic soundwaves travels through the block, they would become additive at certain points/locations in the block. At those magic points where all the waves arrive in phase, the water would boil or cavitate, thus acting like a jack hammer. The much later used of pulsed injection or pilot injection is now used to cause the explosion to start at a lower level to avoid, and to spread the peak combustion pressures a bit, spread the explosion out, and eliminate these over peak pressure waves. It also has the ability to reduce pollution and nox as well, in newer system. Bosh did not have the technology or the understanding of what was happening as they slowly increase the efficiencies of the diesel system at time. The Cummins engineers had studied and issued papers that identified the problem of created the improve injection systems and the pressure/sound waves that accompanied these newer systems. It seemed that the newer diesel technology created faster injection, higher injection pressures, higher/quicker vaporization of fuel, swirl chamber combustion, and much higher/quicker PEAK combustion pressures with the louder, quicker, and more violent explosions...Ironically simply adding a surfactant to break the surface tension of the water, and controlling hard minerals and additives ending up being the stop gap solution to almost eliminate the cavitation problems. Water filters which were really chemical additives that were slowly released into the water were popular for some engine manufactures. Ford had Fw15 as a coolant additive as a final solution to the mysterious porous block problem solver..Strange that a cavitation additive fixed the problem that appeared strongly on the 10 series. The earlier direct injection engines is was found, did have minimal cavitation problems ,in many cases that could take much much longer to pin- hole a cyl wall. ie much later in the life of the engine as those injection systems did not produce the same peak pressures and pressure/sound waves as the later system did.

 

[LarrySTN]

I realize you are the self proclaimed expert here, that being injector breaking pressure is the root cause of cavitation in cylinder walls and cylinder blocks. I've repaired engines for nearly 60 years and always ask why to certain common engine failures. I've personally seen pin holes in sleeves and in parent bore blocks. I've observed 4 cylinder engines being much worse in cavitation issues, much less in 6 cylinder and somewhat rarely in 3 cylinder diesels of the same company, same bore, same stroke, same exact injector breaking pressure with the same horsepower rating per cylinder. This would tend to cause me to hesitate to believe the theory that injector breaking pressure is the root cause. There is way way more at play than injector breaking pressure at cause. It is deeper to understand than just a paragraph.

 

[showcrop]

I had a Ford 9000 for nearly twenty years so I have always paid attention to the cavitation pinhole threads. This is the first of hundreds that I have read where there has been any mention of higher injection pressures creating the subsonic sound waves... That travel through the block and cause the cavitation at a point where the soundwaves all add together.