Diesel injectors

[snowleopard]

Our loss of power problem has been sorted out by fitting new tips to the injectors. The boat is 5 years old and has 1300 hours motoring in the log. The boat next door, also with a Yanmar, changed theirs at 2000 hours. Both boats have spent at least a season in the Caribbean so may have had manky fuel.

How common is it to need to do this? It cost over €1000 for 4 injectors so not something to be done lightly. I have noticed some loss of top-end power on my own engines so think I may have to do the same (1700 hours, 2x3 cylinders). Mine have also had a season in the Caribbean and one has had a bad attack of diesel bug.

Any experiences to share? Any tips on keeping down the cost?

 

[Marsupial]

Injectors

1300 hours seems a bit early for injector troubles UNLESS the engines have been run for a long time at low rpm. Its quite possible that the fuel is not atomising as the holes are blocked by carbon. I would try these two solutions before taking a spanner to the engine.

Run for a day at high rpm, 80% of max

AND/OR

Invest in a bottle of injector cleaner and follow the instructions.

Yanmar do advise running the engine up to max revs as you turn off to prevent carbon fouling of the injectors but few of us do it.

 

[boatmike]

1300 hours seems a bit early for injector troubles UNLESS the engines have been run for a long time at low rpm. Its quite possible that the fuel is not atomising as the holes are blocked by carbon. I would try these two solutions before taking a spanner to the engine.

Run for a day at high rpm, 80% of max

AND/OR

Invest in a bottle of injector cleaner and follow the instructions.

Yanmar do advise running the engine up to max revs as you turn off to prevent carbon fouling of the injectors but few of us do it.

Agree with that, but if you suspect power loss don't replace your injectors as a "first fix" There are many other causes that are likely contributing factors. If you suspect the injectors take them to a reputable diesel shop and have the spray pattern tested. It's easy and cheap and will tell you if it's a worthwhile expense.

 

[Heckler]

Our loss of power problem has been sorted out by fitting new tips to the injectors. The boat is 5 years old and has 1300 hours motoring in the log. The boat next door, also with a Yanmar, changed theirs at 2000 hours. Both boats have spent at least a season in the Caribbean so may have had manky fuel.

How common is it to need to do this? It cost over €1000 for 4 injectors so not something to be done lightly. I have noticed some loss of top-end power on my own engines so think I may have to do the same (1700 hours, 2x3 cylinders). Mine have also had a season in the Caribbean and one has had a bad attack of diesel bug.

Any experiences to share? Any tips on keeping down the cost?

As has been said, take em out and get them tested to check the break point and spray pattern. You can actually remove them, attach them to the inj pipes outside the engine and turn it over by hand, you will then see and hear the injector working. When they "break" there is a "creaking" sound and 4 (usually, for the pedants!) jets of atomised diesel spray out. You can "rock" the engine at that point to repeat the sequence. BE CAREFUL!!!! put cloths to catch the spray and DONT let it hit you!! It penetrates skin easily. 3000psi or thereabouts! The "creaking" is a good pointer to say that the inj is working ok, coupled with good atomisation. If you get dribbles or solid jets of fuel the nozzles need attention. In the olden days i used to service Rolls Royce and Ford injectors. They strip fairly easily and we used to have a kit of brass prodders, brushes etc to clean them up, we would ream the carbon out of the spray holes with brass prodders, this would be followed by re assembly and then re setting on a hand pump with a big pressure guage.
I have lapped bad nozzle needles and seats with brasso before now to get them to seat properly.
In an emergency!!!, if note is taken of where the adjusting nut is so that they can be re assembled somewhere near,they can be taken apart cleaned and put back in service to get you home!!
Bottom line 1000 euros seems v expensive for a set of new nozzles, you need to take them to a truck type injector shop to get the best deal.
Stu
PS a random sample of stuff on ebay here http://shop.ebay.co.uk/?_from=R40&_...kw=injector+nozzles&_sacat=See-All-Categories

 

[boatmike]

Stu. I agree with everything you say and would and have done similar myself. I never recommend others to do it though as when I did my apprenticeship (with CAV) I was shown pictures of people who had been blinded, disfigured and in some cases killed doing it. The heart pumps diesel fuel around thebody just the same as blood, but it does not do you a lot of good I can assure you!
If you are going to mess around like this be aware of the dangers and please please make up something to bolt the injector down to, to ensure it is pointed away from you and others when you do. I would much rather see them taken out and given to a diesel shop to test.
Not disagreeing with you you understand but I think your health warning should be stronger for those with poor imagination....

 

[Heckler]

Stu. I agree with everything you say and would and have done similar myself. I never recommend others to do it though as when I did my apprenticeship (with CAV) I was shown pictures of people who had been blinded, disfigured and in some cases killed doing it. The heart pumps diesel fuel around thebody just the same as blood, but it does not do you a lot of good I can assure you!
If you are going to mess around like this be aware of the dangers and please please make up something to bolt the injector down to, to ensure it is pointed away from you and others when you do. I would much rather see them taken out and given to a diesel shop to test.
Not disagreeing with you you understand but I think your health warning should be stronger for those with poor imagination....

We live in a cossetted world, I think my warnings are strong enough, yours certainly re inforce them, I have done hundreds of them, even when I was a hairy ars ed youth with no regard for so called safety, I never came close to getting hit with the spray pattern. I have done hundreds of tests as described above, again never been hit. Sometimes we suck our teeth too much but the message will, i suspect, have been got across!
Stu

 

[Marsupial]

most of the above is why I suggested non invasive surgery on the engine as a first point of call. When you get into the realms of cracking fuel pipes and removing injectors to observe the spray pattern you run many risks, not least fire - filling a space with atomised fuel is very bad news, not so bad on a truck in the open but on a boat very dangerous, and health issues of injecting diesel are legion, yes some of us who were brought up on engine oil have managed to avoid those issues over the years but its not good advice on a forum where you cant see or hear the actual circumstances of the problem.

please let's keep diy safe for the novices out there.

 

[Bilgediver]

Our loss of power problem has been sorted out by fitting new tips to the injectors. The boat is 5 years old and has 1300 hours motoring in the log. The boat next door, also with a Yanmar, changed theirs at 2000 hours. Both boats have spent at least a season in the Caribbean so may have had manky fuel.

How common is it to need to do this? It cost over €1000 for 4 injectors so not something to be done lightly. I have noticed some loss of top-end power on my own engines so think I may have to do the same (1700 hours, 2x3 cylinders). Mine have also had a season in the Caribbean and one has had a bad attack of diesel bug.

Any experiences to share? Any tips on keeping down the cost?

Firstly the price you give is out of all proportion for the cost of injector nozzles(tips) for dinky wee Yanma's and Volvo engines.

It sounds like your friendly purveyor sold you complete injectors and pocketed your old ones?????

Injector nozzles are usually standard items and can be obtained by most good injector shops from the usual supplier IE Bosch etc .

It is possible that if you have had bugs then you have been putting water through the nozzles and they don t like that. It can mess up the internal seats. The bugs don t help either as their deposits are acidic and this etches the polished parts .

Try and keep all free water out of your fuel tanks and do not test the efficiency and ability of your filters to remove water and bugs .

Injectors will last 1000 s of hours with clean fuel and running at a decent load
however yacht engines do not always achieve this. It is good practice to remove the injectors at least annually and have a look at them. The appearance of the tip of the nozzle tells a lot about what is going on. Any carbon deposits are easily wiped off and if the injector body is well greased with a high temperature copper based grease then the nozzles will come out easily next time. Always anneal the copper washers if fitted by heating to red heat over the cooker and plunging into cold water.

If there is excessive hard carbon showing the outline of the nozzle pattern then that nozzle needs servicing or replacement.

You can get an idea of your nozzles condition on small engines by turning the engine over by hand with the throttle set to half speed and decompressed and listening to the sound of the nozzles. It should be a definite squeek.

Unfortunately it is not possible to do this any many installations

 

[Malish]

From my experience with diesel injectors (on a Land Rover) make sure you source them from a proven source with clear links to the original supplier - Delphi, Bosch etc. Pattern parts are not worth the saving - I had a pattern nozzle split along the length of its face; separately I have also been sold 'refurbished' injectors whose fuel release pressures had not been set correctly.

 

[sailorman]

Firstly the price you give is out of all proportion for the cost of injector nozzles(tips) for dinky wee Yanma's and Volvo engines.

It sounds like your friendly purveyor sold you complete injectors and pocketed your old ones?????

Injector nozzles are usually standard items and can be obtained by most good injector shops from the usual supplier IE Bosch etc .

It is possible that if you have had bugs then you have been putting water through the nozzles and they don t like that. It can mess up the internal seats. The bugs don t help either as their deposits are acidic and this etches the polished parts .

Try and keep all free water out of your fuel tanks and do not test the efficiency and ability of your filters to remove water and bugs .

Injectors will last 1000 s of hours with clean fuel and running at a decent load
however yacht engines do not always achieve this. It is good practice to remove the injectors at least annually and have a look at them. The appearance of the tip of the nozzle tells a lot about what is going on. Any carbon deposits are easily wiped off and if the injector body is well greased with a high temperature copper based grease then the nozzles will come out easily next time. Always anneal the copper washers if fitted by heating to red heat over the cooker and plunging into cold water.

If there is excessive hard carbon showing the outline of the nozzle pattern then that nozzle needs servicing or replacement.

You can get an idea of your nozzles condition on small engines by turning the engine over by hand with the throttle set to half speed and decompressed and listening to the sound of the nozzles. It should be a definite squeek.

Unfortunately it is not possible to do this any many installations

Always anneal the copper washers if fitted by heating to red heat over the cooker and plunging into cold water.

cool down naturally surely

 

[Heckler]

most of the above is why I suggested non invasive surgery on the engine as a first point of call. When you get into the realms of cracking fuel pipes and removing injectors to observe the spray pattern you run many risks, not least fire - filling a space with atomised fuel is very bad news, not so bad on a truck in the open but on a boat very dangerous, and health issues of injecting diesel are legion, yes some of us who were brought up on engine oil have managed to avoid those issues over the years but its not good advice on a forum where you cant see or hear the actual circumstances of the problem.

please let's keep diy safe for the novices out there.

Work for the H&SE do we?
Why do peeps do toothsucking on here? Is it to prove they know more than any one else?
A typical OTT response, the amount of fuel atomised in my engine space would be the equivalent of two squirts per injector, less than the atomised spray from a fly killer spray AND without the benefit of a propane propellant!
Stu

 

[Heckler]

Always anneal the copper washers if fitted by heating to red heat over the cooker and plunging into cold water.

cool down naturally surely

nah, cold water for the satisfying psss and the working off of copper oxide to leave a lovely pink finish!
Stu

 

[boatmike]

Work for the H&SE do we?
Why do peeps do toothsucking on here? Is it to prove they know more than any one else?
A typical OTT response, the amount of fuel atomised in my engine space would be the equivalent of two squirts per injector, less than the atomised spray from a fly killer spray AND without the benefit of a propane propellant!
Stu

Actually Stu no one is trying to prove they know more than you and your reaction is more "typical" as you put it than either of ours. Neither of us dissagreed with your post and neither is trying to do any more than alert novices that may read your post to the very real dangers. Calm down dear and stop taking everything personally. That's how all the arguments start on here.....