Jump to content

Diesel leak on injection pump


Darryl

Featured Posts

Hi,

I have a small leak on a BMC 1.5 at the injection pump. I've arrowed the place.

Looks to be at the copper joint.

The nut is tight and awkward to get a spanner on.

I'm guessing I'll have to get a new pipe made with a flared end and hopefully that will resolve the issue.

Currently the leak is small and engine runs fine

 

What kind of pain am I likely to encounter if I start trying to disconnect/replace this?

 

Many thanks.20210518_184642.jpg.0fa600e02ea105cfe8c7da124f8bbf48.jpg

Link to comment
Share on other sites

That seems to be the main input fuel pipe from the filter to the pump. I think it has an olive on the pipe so the pipe is probably crushed. It screws into a large hexagon and under that large hexagon is a plastic strainer, the regulating valve plus some springs so on no account take that alrge hexagon out.

 

Turn the fuel isolator off before undoing anything

Link to comment
Share on other sites

Hi Tony,

Thanks for the guidance. I briefly tried a spanner on the small hex to tighten and it didn't move at all, so likely been attempted to fix by tightening already.

 

I'll try to get a spanner on the large hex to lock it when the time comes to release the pipe.

 

Am I right in thinking that as soon as take that pipe off (it's actually only about 8" long with a bend in the middle and connected into flexible hose before the filter, just out of image) that it's a full bleed process?

 

Having never done that on these engines, perhaps changing the filter at the same time makes sense and doing both in the future.

Ideally I don't yet want to have to bleed it yet, as I've only just got the engine running since working on an unrelated issue.

 

Thanks again.

 

20210518_184635.jpg

Link to comment
Share on other sites

If you leave the union we are discussing loose and then use the priming lever on the lift pump until air free fuel flows from the loose union and then do it up while still priming you stand  a good chance of not having to bleed the system because you would have expelled the air in that pipe.

 

If that does not work the bleed the pump from the screw on the cylindrical body but I avoid the one under the pipes on the governor turret you can see in your photo. Only use that one if you really have to. I have seen to many inserts around that screw torn out of the turret, they are often glued in, Keep priming for at least 30 seconds AFTER you think you have cleared the air from the pump. Then bleed the injectors.

 

If you change the filter as well you may need a full bleed but if you bleed the filter head and then the union for 30 seconds after you think you have cleared the air you may not need to bleed the rest.

 

Edited by Tony Brooks
Link to comment
Share on other sites

Get a flare nut spanner of the correct size, with 5 flats to grip it is better than an open ender.

 

To avoid having to bleed always fill pipes and filters with fuel by leaving unions slack and pumping till all the air is out then tighten up.

Link to comment
Share on other sites

Tony & Tracy.

Thanks for comments and advice.

I think perhaps now is the time to invest in a flaring tool kit :)

 

which I guess brings me onto,

Anyone know what diameter flare is required there?

I have various manuals but prefer real and more recent experience if available.

Thanks again!

 

Edited by Darryl
Link to comment
Share on other sites

23 minutes ago, Darryl said:

Tony & Tracy.

Thanks for comments and advice.

I think perhaps now is the time to invest in a flaring tool kit :)

 

which I guess brings me onto,

Anyone know what diameter flare is required there?

I have various manuals but prefer real and more recent experience if available.

Thanks again!

 

 

Tracy said use a flare SPANNER otherwise known as a brake pipe spanner. Its like a heavy-duty hexagon ring spanner with a slot cut in the end to slide around the pipe.

 

As I said I am all but sure that union uses an olive on the pipe although I suppose a break pipe nipple flared on the end of the pipe might work. Can't be 100% sure about the olive though because its about 45 years since I have had one apart. If it was not an olive I am sure Tracy would have said corrected me.

Link to comment
Share on other sites

1 minute ago, Darryl said:

Thanks Tony,

I'll cross check the manuals and diagrams I have to confirm.

Understood what Tracy said but then it led me in another direction.

 

Olive would be even easier -id hope!

 

FWIW I visualise brass olives on a steel pipe, although your pipe is copper. In fact if someone has used a brass olive that my have contributed to crushing the pipe.

Link to comment
Share on other sites

As far as I can remember, like Tony, it has been a while, they are connected with copper olives on plain unflared pipe.

 

Flare nut spanner look like these, I don't know what size you would need but it will be an across flats imperial size.

https://www.google.com/search?q=flare+nut+spanner+picture&rlz=1C1CHBF_en-GBGB920GB920&sxsrf=ALeKk00w0ehhFlIvlNfKXfNOSCaHfs3giw:1621770902426&tbm=isch&source=iu&ictx=1&fir=BruZKqdLm9yiBM%2C8v8vn3WjyIhhSM%2C_&vet=1&usg=AI4_-kSCojOsn9Rmjpdm2pOUGpm6wVQ3mw&sa=X&ved=2ahUKEwjs1K6039_wAhXQA2MBHcTcBbcQ9QF6BAgKEAE#imgrc=BruZKqdLm9yiBM

Link to comment
Share on other sites

It's all a current mystery. But the engine is running right now, so I'm open to as much research and suggestions as possible before I take it apart and have surprises when it isn't running until it's fixed.

The pipe itself going into that joint can be wobbled, so something is a bad fit!

Just now, Tracy D'arth said:

As far as I can remember, like Tony, it has been a while, they are connected with copper olives on plain unflared pipe.

 

Flare nut spanner look like these, I don't know what size you would need but it will be an across flats imperial size.

https://www.google.com/search?q=flare+nut+spanner+picture&rlz=1C1CHBF_en-GBGB920GB920&sxsrf=ALeKk00w0ehhFlIvlNfKXfNOSCaHfs3giw:1621770902426&tbm=isch&source=iu&ictx=1&fir=BruZKqdLm9yiBM%2C8v8vn3WjyIhhSM%2C_&vet=1&usg=AI4_-kSCojOsn9Rmjpdm2pOUGpm6wVQ3mw&sa=X&ved=2ahUKEwjs1K6039_wAhXQA2MBHcTcBbcQ9QF6BAgKEAE#imgrc=BruZKqdLm9yiBM

Thanks!,

We used to have all this kit when we had lorries way back too. A flare nut socket might also fit over considering the other things conflicting in the area too.

Link to comment
Share on other sites

1 minute ago, Darryl said:

It's all a current mystery. But the engine is running right now, so I'm open to as much research and suggestions as possible before I take it apart and have surprises when it isn't running until it's fixed.

The pipe itself going into that joint can be wobbled, so something is a bad fit!

 

The union nut is usually a sliding fit on the pipe so you should not be able to wobble it BUT that type of union is available in two different pipe sizes for use in other applications so someone may have fitted  a 5/16" union nut on a 6mm pipe. Another possibility is that your coper pipe is metric when it should be imperial.

Link to comment
Share on other sites

6 minutes ago, Darryl said:

It's all a current mystery. But the engine is running right now, so I'm open to as much research and suggestions as possible before I take it apart and have surprises when it isn't running until it's fixed.

The pipe itself going into that joint can be wobbled, so something is a bad fit!

Thanks!,

We used to have all this kit when we had lorries way back too. A flare nut socket might also fit over considering the other things conflicting in the area too.

By flare nut socket do you mean a crowfoot wrench?

Link to comment
Share on other sites

8 minutes ago, Tracy D'arth said:

By flare nut socket do you mean a crowfoot wrench?

 

I think he must. If he dropped that clunky home-made cable anchor off the pump he would have few access problems, only four or less small nuts.

 

Further thought about this. Daryl said the pipe goes to a length of flexible that screws fits onto the filter. That is an ongoing recipe for more leaking problems. It will allow the engine vibrations to wave the copper pipe around. I have seen leak off pipes snapped by inadequate filter supports allowing the filter to wave about so a length of pipe that has one end on a flexible is likely to be worse.

 

Obviousey not now he has posted the link but those sockets would barely allow a 1 flat turn before they needed repositioning and that assume the pipe bends away from the vertical soon enough to get the socket on.

Edited by Tony Brooks
Link to comment
Share on other sites

11 minutes ago, Tony Brooks said:

 

The union nut is usually a sliding fit on the pipe so you should not be able to wobble it BUT that type of union is available in two different pipe sizes for use in other applications so someone may have fitted  a 5/16" union nut on a 6mm pipe. Another possibility is that your coper pipe is metric when it should be imperial.

I was also thinking something like that could have happened (especially as the pipe between the pump and filter isn't all copper, it has rubber pipe in the middle. Or when cutting it to fit the rubber/change filter it was levered and loosened.

Fortunately as it does into rubber I'm only dealing with one end to figure out.

Do you know the correct diameter that should be used there? I'll get replacement pipes and olives

 

Thanks again!

6 minutes ago, Tony Brooks said:

 

I think he must. If he dropped that clunky home-made cable anchor off the pump he would have few access problems, only four or less small nuts.

 

Further thought about this. Daryl said the pipe goes to a length of flexible that screws fits onto the filter. That is an ongoing recipe for more leaking problems. It will allow the engine vibrations to wave the copper pipe around. I have seen leak off pipes snapped by inadequate filter supports allowing the filter to wave about so a length of pipe that has one end on a flexible is likely to be worse.

 

Obviousey not now he has posted the link but those sockets would barely allow a 1 flat turn before they needed repositioning and that assume the pipe bends away from the vertical soon enough to get the socket on.

You are right, but it's also mega awkward to get a spanner in-between everything too!

Link to comment
Share on other sites

1 minute ago, Darryl said:

I was also thinking something like that could have happened (especially as the pipe between the pump and filter isn't all copper, it has rubber pipe in the middle. Or when cutting it to fit the rubber/change filter it was levered and loosened.

Fortunately as it does into rubber I'm only dealing with one end to figure out.

Do you know the correct diameter that should be used there? I'll get replacement pipes and olives

 

Thanks again!

 

Sorry, no idea, it's not something I have ever had to do because the pipes were steel. I would see how well the pipe fits into the filter olive and if it's a nice sliding ft with little clearance the union's bore would give the size. It will be either 1/4" or 5/15".

 

I have no idea why the pipe needed levering to change the filter. It is simply is not an obstruction unless your engine is a "Fred in a shed" marinisation and if so all bets are off. I would suggest you may do well to see if Calcutt can supply the correct steel pipe.

Link to comment
Share on other sites

It should be 5/16" OD soft drawn copper pipe, you can measure what you have with a spanner if you have no vernier.

A  5/16" or 8mm open end spanner should be a comfy fit around it.

 

If you need to have a flexible pipe, buy a made up flexy fuel pipe long enough to reach both ends, which has 5/16" metal ends made on.

Do not fit half flexy and half rigid pipe, that is a recipe for failure.

Link to comment
Share on other sites

Hi Tracy,

Thanks for that. The boat is 'new to me', so everything is a discovery.

Probably a made up Flexi is better long term.

I'll measure the pipe next time I'm at the boat.

I've been working on some other engine issues and although the leak is currently small, I just wanted to stop it with the least extra drama while I'm running the motor and checking the other bigger issues are resolved.

 

I thought I read somewhere in the BSS guidelines about having solid copper piping between joints (could have been across injectors) and maybe that was interpreted for the pump to filter connection.

Truth is, it could be many reasons, but I appreciate all the best practice advice from you and Tony, which will definitely be really helpful to make things better as they are addressed.

Link to comment
Share on other sites

7 minutes ago, Darryl said:

 

 

I thought I read somewhere in the BSS guidelines about having solid copper piping between joints (could have been across injectors) and maybe that was interpreted for the pump to filter connection.

 

  

 

This refers to the  spill rail that goes on the tops of the injectors.

Link to comment
Share on other sites

I think the BSS says or said that flexible hoses should be "the minimum length" so if metal pipes are available a picky BSS examiner could argue the flexible is not of the minimum length i.e. Zero length. The flexible must also meet certain minimum standards and things like the spiral bound flexibles may well not have the markings visible. Hence my preference for a metal pipe if possible. No argument and aggro.

Link to comment
Share on other sites

10 hours ago, Tony Brooks said:

 

Tracy said use a flare SPANNER otherwise known as a brake pipe spanner. Its like a heavy-duty hexagon ring spanner with a slot cut in the end to slide around the pipe.

 

 

Although I haven't used this technique in this position, I have used many time it for brake lines for those troublesome unions.

 

If you don't have a brake pipe spanner and can remove the union on the filter more easily, you may be able to slide a ring down onto the union on the pump, and a best chance of getting this to move without rounding off the nut.

 

If you intend to get a 5 sided brake spanner, get a good one. Some are poorly toleranced and you're back to square one, well in a 6 sided way.

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.