3910 vibrations

[Texasmark]

Several years ago I bought a 3910 series II at an estate sale with 900ish hours. Other than the right brake squealing when you apply it, the only rub I have are engine vibrations starting at about 1600 and going through 1800 where they seem to subside somewhat before the pump stops the RPMs at 2000.....but the 540 PTO is at 1800. I've put a couple of hundred hours on it since, useing PS in my fuel with Gold whatever you call it final filtration at my outlet hose and just don't have any other problems.

I have cracked the inlet connector to the injectors and got the responses you would expect....I have and have had probably a couple dozen Fords over the last 40 years and never had this problem with any of them with the largest being the 4610 I bought used and had no vibrations to speak of if my memory serves me correctly...but its been a while and memory is like my age.......it had the 4.4x4.2 engine and it may have had them too...maybe you can help me remember if its inherent in the design.

Since the 3 cyls don't have vibration dampers, and the only difference between my smooth running 4.2x4.2 engines vs this 4.4x4.2 should I expect to have this annoying vibration? With these few hours, I can't believe a new tractor purchaser would put up with this crap if it's inherent in the design, upon contemplating the purchase of a new tractor.

I have posted on here concerning this problem but I am about to spring for a new set of injectors...SWAGing that maybe one of them may be the problem.....you folks could save me some money hopefully.

As usual, responses are surely welcomed.
Thanks,
Mark

 

[Texasmark]

I got on the www and found suppliers of injectors selling the same injector for a 2000 Ford all the way up to the 6000 series. Well since the injector puts the fuel into the cubic inches, regardless of the size, it just dawned on me......daaaaaa. the injector pump decides how much fuel is squirted once the injector opens.....yes....no??????

 

[sotxbill]

There was a change where they went from 4 holes to 6 holes in the nozzle.. or something like that.... in either the x600 series or later iirc... but I believe the newer injectors can be used on the older...... but would recommend all injectors be of the same type.

Wait, it was a revised nozzle that changed the angle of the spray... AND there were different nozzle part numbers and assembly part numbers used for the various sized tractors... as the x600 series came out.. and the suppliment says they are NOT interchangeable with early injectors.. So now I wonder about the aftermarket injectors saying that they fit all the models. (service manual suppliment part 2 fuel systems, page 1)

 

[Texasmark]

There was a change where they went from 4 holes to 6 holes in the nozzle.. or something like that.... in either the x600 series or later iirc... but I believe the newer injectors can be used on the older...... but would recommend all injectors be of the same type.

Wait, it was a revised nozzle that changed the angle of the spray... AND there were different nozzle part numbers and assembly part numbers used for the various sized tractors... as the x600 series came out.. and the suppliment says they are NOT interchangeable with early injectors.. So now I wonder about the aftermarket injectors saying that they fit all the models. (service manual suppliment part 2 fuel systems, page 1)

Bill, do you have some OEM part numbers for the later injectors? The suppliers give the OEM part numbers of the injectors they are selling. Maybe if I knew what I was looking for it would help.
Thanks,
Mark

 

[Sean in PA]

Your 4610 should have been the 201 ci 4.4" bore x 4.4" stroke engine. That 192 ci 4.4 x 4.2 in your 3910 wasn't used in a lot of different models.

 

[Dieseltech]

The spec book I have shows the early 3910 should have CAV tip BDLL150S6780CF. Injection pump max fuel setting code is 58, 63, or 69 CC depending on pump model number.

 

[Texasmark]

Your 4610 should have been the 201 ci 4.4" bore x 4.4" stroke engine. That 192 ci 4.4 x 4.2 in your 3910 wasn't used in a lot of different models.

I don't remember on the 4000 series....may have been just a 4600.....I was thinking that it was a 3 cylinder and that you had to get into the 5000 series to get the 4th cylinder at the time I had it. It was decades ago that I had that tractor....I think I had it around the year 2000 to 2005 time line. I would really like to know some part numbers of the 6 hole nozzles injectors.

 

[Texasmark]

I went back to the ebay site and found more information and for the XX10 series of tractors this is the correct part number:
D9NN9F593BA

 

[Dieseltech]

I went back to the ebay site and found more information and for the XX10 series of tractors this is the correct part number:
D9NN9F593BA

That's the EARLY injector assembly number, the LATEST injector is E9NN9F593CA which is the latest low spring type injector that has tip 6801110.

 

[Texasmark]

I ordered the ones I mentioned with a set of new seals. I'll know one thing for sure after installing them....did I have a loafing injector or not....I've been wondering that since I bought the tractor. I was thinking about doing the installation and a thought occurred to me......do one at a time and you will have the other two cylinders to get the tractor back running so that you can bleed the fuel line to the injector you replaced....should be a walk in the park vs changing all at once and having to grind on the starter to get fuel up there and get a couple of cylinders firing enough to get the engine running.

Here is the ebay posting for that later model injector. As I mentioned earlier, 3910 is not among the candidates:

3X Fuel Injector E9NN9F593CA for Ford 3230 3430 3930 4130 4630 250C 260C 345C+ | eBay

Find many great new & used options and get the best deals for 3X Fuel Injector E9NN9F593CA for Ford 3230 3430 3930 4130 4630 250C 260C 345C+ at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[Dieseltech]

TI ordered the ones I mentioned with a set of new seals. I'll know one thing for sure after installing them....did I have a loafing injector or not....I've been wondering that since I bought the tractor. I was thinking about doing the installation and a thought occurred to me......do one at a time and you will have the other two cylinders to get the tractor back running so that you can bleed the fuel line to the injector you replaced....should be a walk in the park vs changing all at once and having to grind on the starter to get fuel up there and get a couple of cylinders firing enough to get the engine running.

Here is the ebay posting for that later model injector. As I mentioned earlier, 3910 is not among the candidates:

3X Fuel Injector E9NN9F593CA for Ford 3230 3430 3930 4130 4630 250C 260C 345C+ | eBay

Find many great new & used options and get the best deals for 3X Fuel Injector E9NN9F593CA for Ford 3230 3430 3930 4130 4630 250C 260C 345C+ at the best online prices at eBay! Free shipping for many products!

www.ebay.com

The EARLY injectors have the spring on top of the spindle that holds the tip valve closed. the LATEST injectors don't use that long spindle and have a short spindle that sets on the tip valve. With the lower spring design there's less weight to move when the pump delivers fuel to the injectors. The injector bodies are similar but there's no screw top/cap nut for setting the opening pressure. Shims are used to set the opening pressure. The early injectors are set at 2720 PSI when new, the latest is 3400 on the spec list I have for the late 3910.

 

[Sean in PA]

Someone selling on ebay doesn't necessarily know or list all of the tractor models that a particular part might fit, especially on the oddball models with the 192 ci engine. Listen to Dieseltech. He is a certified diesel mechanic that works on these Ford tractor fuel injection systems on a regular basis and he has all of the reference materials. If he says that those injectors will work on your tractor, believe him.

 

[Texasmark]

The EARLY injectors have the spring on top of the spindle that holds the tip valve closed. the LATEST injectors don't use that long spindle and have a short spindle that sets on the tip valve. With the lower spring design there's less weight to move when the pump delivers fuel to the injectors. The injector bodies are similar but there's no screw top/cap nut for setting the opening pressure. Shims are used to set the opening pressure. The early injectors are set at 2720 PSI when new, the latest is 3400 on the spec list I have for the late 3910.

I have the series II 3910 so I guess that's the later model. Ok sir, you are the professional doing this for a living, I'm just a guy interested in maybe get my higher RPM vibrations to stop.

As a game plan I will order the E9NN9F593CA and return the ones I already bought. As I mentioned I also bought a gasket kit which has the injector mounting seal plus some small ones which I guess are for servicing the injectors which I THINK I won't have to do anything but install them, bleed off the air and that's it......is that it or do I have to tweak this or that on the opening pressure as you mentioned? Oh, and I have the rotary CAV pump.

I do appreciate your taking the time to steer me in the right direction on this....having your expertise available here on this forum is super!!!!!

An afterthought: If I currently have the old style will there be any tweaks necessary when installing the new type?

 

[Destroked 450]

I have the series II 3910 so I guess that's the later model. Ok sir, you are the professional doing this for a living, I'm just a guy interested in maybe get my higher RPM vibrations to stop.

As a game plan I will order the E9NN9F593CA and return the ones I already bought. As I mentioned I also bought a gasket kit which has the injector mounting seal plus some small ones which I guess are for servicing the injectors which I THINK I won't have to do anything but install them, bleed off the air and that's it......is that it or do I have to tweak this or that on the opening pressure as you mentioned? Oh, and I have the rotary CAV pump.

I do appreciate your taking the time to steer me in the right direction on this....having your expertise available here on this forum is super!!!!!

An afterthought: If I currently have the old style will there be any tweaks necessary when installing the new type?

What year is your 3910?
Series II production begin in 86, the low top injectors where first used after 8/87, so your tractor could have either one depending on when it was built

 

[Texasmark]

What year is your 3910?
Series II production begin in 86, the low top injectors where first used after 8/87, so your tractor could have either one depending on when it was built

Thanks, I'll go out and get some numbers and "we" can decide on the build date. Be back shortly.

 

[Texasmark]

On the FEL attachment point...land I guess, to the immediate rear of the starter on the right side of the tractor, the following appears:
Upper stamping is: 8J24B Lower stamping is: 76378. The decal on the hood sheet metal is really hard to read but I see the following numbers (I think): 76378, 8J228, and the lowest entry on that decal is 8J24A.
Does that help?
Thanks again,
Mark

 

[Sean in PA]

8J24B is an assembly date of September 24, 1988 during the day shift. The other date codes on the sticker under the hood are assembly dates for the various major components. 8J228 is most likely 8J22B, which would be September 22, 1988 during the day shift. 8J24A is September 24, 1988 during the midnight shift. I am not sure what 76378 would be, unless it might be 7G31B, which would be August 31, 1977 during the day shift. It definitely looks like your tractor left the assembly line on September 24, 1988.

 

[Texasmark]

Well guys.........looks like the later injectors (E9NN9F593CA) are the correct ones for my tractor. I really appreciate all the professional help one gets on this forum. Just a wonderful gift that we have this forum for us to solve each other's problems. Have a great day!

 

[Texasmark]

I just took a shower as I am through for the day and besides singing to myself, I had a thought:

Since the 4.4x4.2 was designed earlier with the old injectors, could it possibly be that the engine doesn't like the later model change and if I went back to the original design injectors the problem will disappear. We are only talking about a hundred and fifty bucks to possibly waste in testing this curiosity, but I want the problem solved. This little money that I could eat because I tried a set and they didn't work and I tried the other set and they worked, I wouldn't want to return the used injectors to the seller.....what I did was my doings, not his even though the sellers accept returns.

 

[Sean in PA]

If you want to know it's right, pull the injection pump and injectors and send them all to Dieseltech. He'll test everything, fix what isn't right and fine tune things so that it should run great for another 1000 hours.