966 return check valve replacement issues

[GBell966]

Hello everyone. Finally got around to changing the dangerous check valve and elbow on the return to the injector pump today. Theres no way to shut the return off on my 966, so its a job that has to be done quickly. Unfortunately for me, what looked like an original check valve fitting was actually an orfice. The hard line had a piece of rubber around the base of the flare that broke off when i removed the line. Already had the new fittings ready so put those on while diesel is spewing everywhere. Without that rubber spacer, it wont seal. The flared end just fits loosly while diesel spews around it. Any ideas what i need to do here? Pictures attached. Luckily i had this hose laying around or i woulda lost a lot more diesel to the ground

[HydroTek]

Amazon sells those line packings -- or see your dealer 

[GBell966]

1 minute ago, HydroTek said:

Amazon sells those line packings -- or see your dealer 

Thanks! So thats normal? Never saw a flared fitting with rubber before it before. Looked around on amazon just now, any idea what the name for them is? Cant seem to find em

[TB5288]

I've never seen a check valve installed there, always an orifice. Just go to the dealer and ask for a 3l8 rubber compression sleeve. Make sure you get all the old one dug out of the nut. 

[HydroTek]

3 hours ago, GBell966 said:

Thanks! So thats normal? Never saw a flared fitting with rubber before it before. Looked around on amazon just now, any idea what the name for them is? Cant seem to find em

Dunno -- I typed "fuel line packing sleeve" in and got a page full of them -- maybe you are weak with the amazon foo 

[Mike56073]

The 3/8" tube sleeve for those engines is #9846567.  That's for the fuel lines and the coolant lines on the other side of the block.

The 1/4" tube sleeve for the small oil line under the injection pump is #87017023.

Those are the current CaseIH numbers

That "sleeve system" allows the pipes to be misaligned and still seal, plus they can handle vibration better than a hard flared end.

Like TB5288 said, be sure to get the old sleeve out of the threaded nut.  A good o ring pick and some patience goes a long way with this.

Without the sleeve in place, the threaded nut can actually fall right off the pipe, this is fairly normal.  When installing, work the new sleeve onto the pipe and push the pipe up into the brass fitting as far as it will go, then tighten the nut down snug, but not too tight.

[GBell966]

12 hours ago, TB5288 said:

I've never seen a check valve installed there, always an orifice. Just go to the dealer and ask for a 3l8 rubber compression sleeve. Make sure you get all the old one dug out of the nut. 

I was told it was original, The one i pulled off had an orfice, but the piece with the orfice was a separate piece inside the fitting so not sure if there was a check valve behind it. The new one i got was a solid piece. Dealers over an hour away so i got some 3/8 sleeves from amazon for now. Thank you for your help!

[GBell966]

Yall are a huge help to me. I figured i was dealing with a messed up flared pipe that someone had rednecked together with a piece of hose. Never seen that before. Out here in a hay barn keeping these tractors going to manage our new property and would feel very alone if i didn’t have this forum. Thanks for everyones help this past month!

[HydroTek]

The update parts for that return -- is a open elbow with the orifice in the line adapter fitting 

the original had the orifice and check valve in the elbow inlet side -- these are the parts that would fall out and get into the throttle valve 

[GBell966]

35 minutes ago, HydroTek said:

The update parts for that return -- is a open elbow with the orifice in the line adapter fitting 

the original had the orifice and check valve in the elbow inlet side -- these are the parts that would fall out and get into the throttle valve 

Well I’ll be. It was original then! Luckily it was still in place in the elbow and not in the pump 

[HydroTek]

Would get you a pic of one -- I have a few in my brass box -- but pics are still not working

I suspect that replacing the soft hose with a hard hose is a contributing factor in the orifice popping out of that elbow -- the soft hose dampens the fuel vibration in that pump

Behind that metal plug that you can see in the elbow inlet , is the orifice plate and a check valve and spring  

None of that is good in the throttle area of that pump -- usually the parts block the throttle in the low position -- but I have had 2 that were opposite -- one threw a rod before the operator was able to figure what todo to kill the engine

Easy way is cut the soft fuel line -- no fuel , engine cant run 
-- or get in a higher gear and hope to choke the engine down 

[GBell966]

31 minutes ago, HydroTek said:

Would get you a pic of one -- I have a few in my brass box -- but pics are still not working

I suspect that replacing the soft hose with a hard hose is a contributing factor in the orifice popping out of that elbow -- the soft hose dampens the fuel vibration in that pump

Behind that metal plug that you can see in the elbow inlet , is the orifice plate and a check valve and spring  

None of that is good in the throttle area of that pump -- usually the parts block the throttle in the low position -- but I have had 2 that were opposite -- one threw a rod before the operator was able to figure what todo to kill the engine

Easy way is cut the soft fuel line -- no fuel , engine cant run 
-- or get in a higher gear and hope to choke the engine down 

Yeah i got enough problems without a run away engine in the mix! I believe it was you that pointed out the original check valve from a different post i had made last month. Wouldn’t have had a clue about it otherwise. With this being an all original low hour unit it makes sense it was still there. Im Lucky it was still intact!

[HydroTek]

Yeah , my memory on which posts I have responded to is weak
usually just respond to the post in front of me ,, not going back to look up previous stuff

 

[GBell966]

36 minutes ago, HydroTek said:

Would get you a pic of one -- I have a few in my brass box -- but pics are still not working

I suspect that replacing the soft hose with a hard hose is a contributing factor in the orifice popping out of that elbow -- the soft hose dampens the fuel vibration in that pump

Behind that metal plug that you can see in the elbow inlet , is the orifice plate and a check valve and spring  

None of that is good in the throttle area of that pump -- usually the parts block the throttle in the low position -- but I have had 2 that were opposite -- one threw a rod before the operator was able to figure what todo to kill the engine

Easy way is cut the soft fuel line -- no fuel , engine cant run 
-- or get in a higher gear and hope to choke the engine down 

Once i run the fuel down a bit more ill have to install some kind of shut off on that return line from the tank. It spews out diesel with a vengeance anytime i go to work on the fuel system

[HydroTek]

I keep plugs for the fuel lines

various plugs for various instances

if you were to forget to open that valve -- and start the engine -- unfortunate things will happen 

Split many many of those tractors -- removing fuel lines and plugging at the tank  was one of the first steps right after taking the transmission drain plugs out 

You shouldn't be "in" the fuel system hardly ever -- years 
and changing filters should not get very little back thru the pump 

[snoshoe]

My thoughts are if he is going to drain down and install shut off. Why not remove the fitting, fish the standpipe out of the tank and braze or silver solder it back together.

Personally I would remove sender. Drill and tap for fitting and make new line to return to top of tank.

I also had visions of bad things happening with shutoff valve but decided he would be unable to bleed and never get it started.

[ComancheStarFarms]

My intent is not to highjack this thread however since we have a 966 & a 1066 I could use some clarification so that if/when I have this problem I’ll have a better idea on what to do.  So, what was the problem that resulted in this posting?  Where’s the check valve located & what dictates its removal & replacement?  And the repair job requires a running engine?  Finally, what leads to a runaway engine & catastrophe?  Thanks in advance for any clarification/education?

[Mike56073]

7 hours ago, ComancheStarFarms said:

My intent is not to highjack this thread however since we have a 966 & a 1066 I could use some clarification so that if/when I have this problem I’ll have a better idea on what to do.  So, what was the problem that resulted in this posting?  Where’s the check valve located & what dictates its removal & replacement?  And the repair job requires a running engine?  Finally, what leads to a runaway engine & catastrophe?  Thanks in advance for any clarification/education?

He wanted to change out the original check valve for an updated return elbow fitting.  On the the original design, there's a check valve that can come loose and fall backwards into the injection pump, jamming it.  That can make the fuel delivery uncontrollable, which could be a bad day.  When IH redesigned it, they went from a check valve to a machined orifice built into the elbow.  This is the elbow that comes out of the injection pump and is connected to the fuel line that's clamped to the engine block(it's the only hard fuel line on that side of the pump). 

       There was a thread about this awhile ago, if you google "ambac 100 return check valve", it comes up, there's some good info with pictures in that.

[snoshoe]

9 hours ago, ComancheStarFarms said:

My intent is not to highjack this thread however since we have a 966 & a 1066 I could use some clarification so that if/when I have this problem I’ll have a better idea on what to do.  So, what was the problem that resulted in this posting?  Where’s the check valve located & what dictates its removal & replacement?  And the repair job requires a running engine?  Finally, what leads to a runaway engine & catastrophe?  Thanks in advance for any clarification/education?

Have to go back a thread for original problem. Op was changing filters and when he removed secondary filter. Fuel kept coming from filter base. Return line on 7's and 9's return to bottom of tank. Fitting in bottom of tank should have a standpipe pressed into it to return fuel to upper level of tank. I believe his standpipe has come loose and fallen out. Allowing fuel to run backwards through the pump. He still has this problem. 10's and up have a different tank and return externally to the top and will not have this problem.

Mike covered the check valve pretty well. I will make one correction. The final update was just a standard brass street elbow. Orifice is machined into the line adapter screwed into it.

The check valve is identified by its square shape which is what caught my eye in his pictures. The first attempt to fix the problem they just left the check valve out of the fitting with just the orifice plate crimped into elbow inlet. I believe this is what op has. They found that orifice plate could come loose and cause the same problems.

Bottom line. Early 66 series. Look for square elbow on back side of pump. If there. Change it.

[HydroTek]

This horse has been beat a few times already ...

Plain street elbow -- and orifice is in the line adapter fitting  
-- fitting has notches in the hex to identify it 

[snoshoe]

Not sure what prompted the running engine comment but the answer is no.

[mrfred54]

Just seen these posts. Whew, glad ya got this figured out. Been changing this fitting for at least the last 40 years. And like snowshoe said, on the 7’s and 9’s running a fuel line to the top of the tank into the sender unit. I drill a 11/32 hole and tap with 1/8 pipe tap. Install elbow and connect a fuel hose. Don’t even have to drain the fuel to remove the return fitting out of the bottom of the tank to install a plug. I hook the shop vac to the fill hole. Duct tape to vac hose to the tank and turn on 

[HydroTek]

I used a venturi fitting and an old fuel cap -- shop vac was always out in the other shop , or somewhere besides the tool room -- LoL

Air hose was right there at my work bay and keep the "tool" handy on the bench shelves 

For sure saves the mess on fuel , hydraulic , or coolant 
also used the vac to suck out head bolt holes from oil and dirt -- made a catch can from a steering reservoir off a JX tractor 

[steelerhawk]

Mrfred54, do you use a fitting like this?

[mrfred54]

1/8 in. pipe thread.  Yes sir