Distributor Type CAV Injection Pump

[Texasmark]

I have been spending a lot of time trying to locate a dripping leak associated with my pump. Currently it appears that the leak is at the lower pump output, one of 3 areas that feed the injector pipes. The line to the injector doesn't appear to be leaking, nor around its retaining nut at the pump. What appears to be leaking is a flat adapter (from a fuel pipe) squared off , flat top and bottom, around the locking mechanism (3 surfaces the 4th being the fuel line) adjacent to that output that apparently is contained by a closed top nut. I assume that the nut's purpose is to secure that line.

I have an expensive service manual on the 3600 and it talks about this and that but doesn't get down to the nitty-gritthy of the fuel system and its components.

What is the purpose of that closed top nut....to hold that flat adapter against the pump, essentially sealing the interface? Is there a seal(s) involved, with respect to the flat flange under the nut that could have failed allowing fuel to drip out?

I have posted this before and from time to time I keep working on it.......having fuel slobbering from that problem area is really undesirable.

Comments certainly appreciated.

 

[shaun wallace]

That closed top nut is actually a bolt. That "block" should have a steel sealing washer on both sides good for one use most of the time. That bolt also has check valve in it

 

[Texasmark]

That closed top nut is actually a bolt. That "block" should have a steel sealing washer on both sides good for one use most of the time. That bolt also has check valve in it

What is the official name for the steel sealing washers so I know what to buy? I assume that that area is connected to the outlet tube that goes to the injector so I will need to bleed that injector when finished........
Thanks for your time Shaun.

 

[Dieseltech]

What is the official name for the steel sealing washers so I know what to buy? I assume that that area is connected to the outlet tube that goes to the injector so I will need to bleed that injector when finished........
Thanks for your time Shaun.

I prefer the CAV 5936 332C mild steel line washers. They will crush a bit like copper and seal better than the hardened steel washers Stanadyne uses.

 

[Texasmark]

I prefer the CAV 5936 332C mild steel line washers. They will crush a bit like copper and seal better than the hardened steel washers Stanadyne uses.

Looks like they are called Banjo seals, or Banjo bolt seals. Found a source: https://dieselitems.com/product/pump-line-washers-12-pack/

Thank you sir. I bought this 3600 last year and the thing has been dripping ever since. I spent several attempts to find the source with no results. Yesterday I tried harder and feel confident that I found the problem. Looking closely at the "Banjo Bolt" installation and associated tube, I can't see any seal on either side of the tube on the bottom outlet of the pump which is the one leaking....the other two are holding just fine.

Just got them ordered. Boy am I a happy camper. I had been figuring I might have to remove the pump and send it off (to you) and all that hassle and looks like its going to be a 15 minute job. What did a farm boy ever do before he found and logged on to this site.

 

[Dieseltech]

Looks like they are called Banjo seals, or Banjo bolt seals. Found a source: https://dieselitems.com/product/pump-line-washers-12-pack/

Thank you sir. I bought this 3600 last year and the thing has been dripping ever since. I spent several attempts to find the source with no results. Yesterday I tried harder and feel confident that I found the problem. Looking closely at the "Banjo Bolt" installation and associated tube, I can't see any seal on either side of the tube on the bottom outlet of the pump which is the one leaking....the other two are holding just fine.

Just got them ordered. Boy am I a happy camper. I had been figuring I might have to remove the pump and send it off (to you) and all that hassle and looks like its going to be a 15 minute job. What did a farm boy ever do before he found and logged on to this site.

When you get the new washers, install them finger snug and then use a wrench and turn 1/3 turn more. If you still have some leaking look closely around the hydraulic head as the head sealing O ring is known to leak after awhile too. I have some extra line washers if you need anymore.

 

[Texasmark]

When you get the new washers, install them finger snug and then use a wrench and turn 1/3 turn more. If you still have some leaking look closely around the hydraulic head as the head sealing O ring is known to leak after awhile too. I have some extra line washers if you need anymore.

I appreciate your tip on washer installation. I would have messed that up for sure........figured that they needed to be good and tight. I will spray the area with brake parts cleaner and air before I start to ensure that I don't introduce any dirt. I was going to see you about the washers I bought but figured it was more of a bother for you than it was worth.

Thanks again,
Mark