CAV pump dripping fuel

[Big Bob W]

I have a BMC 1.5.

For a while, I have noticed a small amount of diesel in the engine bilge needing soaking up.

I have now noticed steady drips of fuel which seem to be coming from where the throttle shaft enters the pump. Drip every 30 sec or so.

I am guessing it is a seal/gasket needing replacement?

If so, how difficult a job is it? Or is there anything else it could be?

Thanks

Bob

Edited March 3, 2019 by Big Bob W

[RLWP]

The spindle wears out, our BMC 1.8 one has gone. I need to replace the assembly

 

Richard

[DaveP]

I've just had this; as Richard says, the spindle wears out.  There are springs n things under the top cover which need to go back in the same place....  So I chickened and gave it to a place for an overhaul. Four days and £200 it came back.  Make sure you put it back exactly lined up with how you took it off the engine - theres a pointer and scribeline to match up.

[Tony Brooks]

Also make sure the throttle control is not trying to force the lever on the pump over too hard against its stop. If it does then it tends to push the spindle to one side so the O ring in the pump "turret" is compressed and leaks. Thai is probably related to wear of the ring, spindle or body which it tends to worsen so well worth checking.

[Big Bob W]

Thanks for the advice. 

Looks like its a fairly common problem.

Whilst I am happy with day to day maintenance, delving into the injection pump worries me! Think this is probably going to go to someone who knows what they are doing.

[Tony Brooks]

As long as you observe utter cleanliness, keep the parts you strip submerged in CLEAN diesel, and ensure you use lint free cleaning/wiping cloths you should be OK to take the "turret off". This will lift up with the governor valve hanging underneath it. Having taken the two long "turret" securing bolts out you should be able to just pull the throttle spindle out of the turret so you can change the O ring. make sure the new O ring is oil/fuel resistant.  Juts work the lever before an dafter you pull the spindle out and having replaced  it to ensure it is working the governor valve as it should.

 

 

 

[john.k]

Excuse my ignorance of BMC product,but is the unit being refered to the "Reversable" DPA hydraulic governor?.....if so ,I have a unit right by me .Or is it the mechanical governor,which needs a good deal more care in removal and replacement.,,,,,,both units use 2x 20c O rings,so repair is very cheap if you do it yourself.

Edited March 5, 2019 by john.k

[Tony Brooks]

7 hours ago, john.k said:

Excuse my ignorance of BMC product,but is the unit being refered to the "Reversable" DPA hydraulic governor?.....if so ,I have a unit right by me .Or is it the mechanical governor,which needs a good deal more care in removal and replacement.,,,,,,both units use 2x 20c O rings,so repair is very cheap if you do it yourself.

 

Most marine 1.5s use the hydrauic governor and I have only ever seen two with mechanical ones. At present I am assuming its the hydraulic one and its the modern variety with an idle and max speed adjusting screw but can't know unless the OP posts a photo.

[john.k]

On the reversible hydraulic governor,its only necessary to remove the screw on the same side as the lever......the spindle is retained by a single groove.........dont disturb the governor mount to the pump,leave the other screw tight,remove the screw ,pull our lever/spindle ,replace O ring ,and re install..............simple,and no gasket is required................if you want, you can replace the stopping lever  o ring in the same way...................dont remove both screws at once,just one,and the governor stays put.

[Big Bob W]

8 hours ago, Tony Brooks said:

At present I am assuming its the hydraulic one and its the modern variety with an idle and max speed adjusting screw but can't know unless the OP posts a photo.

Not the best of photos but here we are:

[Tony Brooks]

Yes, that is the latest hydraulic governor. If you undo and remove the funny "reverse" torx headed screw with the lock wire through it you should be able to pull the throttle spindle out as John K says and then replace the O ring (if you can get to it with the pump in situ).

[Big Bob W]

Thanks Tony - and John.

Yes, access is not too bad. I may just have to remove the oil pressure sensor to allow room to pull out the spindle., that's all.

Need to find a tool to remove that torx screw too!

But not as bad a job as I first thought. Hopefully.

 

[Tony Brooks]

5 minutes ago, Big Bob W said:

Thanks Tony - and John.

Yes, access is not too bad. I may just have to remove the oil pressure sensor to allow room to pull out the spindle., that's all.

Need to find a tool to remove that torx screw too!

But not as bad a job as I first thought. Hopefully.

 

A bi-hex (normal) socket will fit.

[Boater Sam]

Or a ring spanner will fit, they are 12 point too.

[Quattrodave]

On 03/03/2019 at 15:49, DaveP said:

I've just had this; as Richard says, the spindle wears out.  There are springs n things under the top cover which need to go back in the same place....  So I chickened and gave it to a place for an overhaul. Four days and £200 it came back.  Make sure you put it back exactly lined up with how you took it off the engine - theres a pointer and scribeline to match up.

Just wondering who you used for the CAV pump overhaul, are you happy with the worth they did?

[DaveP]

Goods Diesel Pumps in Hommerton.  Yep, happy with their work and worth!  http://goodsdieselpumpsltd.yolasite.com/

[Quattrodave]

Perfect, thank you.