Testing / Replacing Injector

[britinusa]

During our 10 day trip to Bahamas (Bimini), fellow sailors noted that we were ejecting a nasty flush of black goop out of our exhaust when we made a rapid increase in RPMs.
I have seen this on other boats and my interpretation of the cause is that the injectors are probably in need of service / replacement.

So, assuming (I know, I know!) that the problem could be the injectors, and I do not know if they have ever been serviced or replaced in the boat's 30 year history, then I should pull the injectors out and get them tested.

Step 1 is to remove the injectors.

I have seen the breakdown of the injector components elsewhere but do not know if any of the components are 'One Use Only' such as washers etc.

I believe that the process goes something like this (please comment)

• Work on a cold engine
• Lay out rags to capture any fuel spillage
• Remove the 2 fuel connectors between the 3 banjos
• Remove the supply tube to the aft most (#1 or #3?) injector
• Remove the tube from #3 or #1(Foremost) injector to the bleed screw
• Loosen and remove the injector pump tubes to each injector
• Loosen and remove the injectors
• Cover each hole as it is opened to prevent anything dropping into it

Is it that easy? (Ha!)

Here's an older pic of the injectors...

[KWKloeber]

Paul


Replace the crush washer when you have tested/rebuilt/reinstall. Your diesel shop can supply em.
If you don't already have, it's a perfect time to invest in a set of metric "tubing/flare nut wrenches"


kk

[britinusa]

Paul


Replace the crush washer when you have tested/rebuilt/reinstall. Your diesel shop can supply em.
If you don't already have, it's a perfect time to invest in a set of metric "tubing/flare nut wrenches"


kk

Sizes?

[britinusa]

Do these sound about right?
6-pc. Flare Nut Wrench Set - Metric
Drop forged, heat treated, chrome plated carbon steel
15-degree offset for easy access
Ideal for gas, brake, and air conditioning lines
Sizes: 6 x 8, 10 x 12, 13 x 14, 15 x 17, 19 x 21, 22 x 24mm


Do I also need a Torque Wrench (perhaps crows feet wrenchs) if so, what size.

Thanks.

paul

[KWKloeber]

Sure.
Theoretically right now all you need to buy the size on the injector nut. Don't ask, dunno.
But you know how it is with tools. They're good for just about 75% of the time that you'd use a [size=78%]metric [/size][/size][size=78%]open-end or box wrench. [/size]
[/size] For 15 boat bucks -20% coupon, why not go the full Monty?[size=78%]

[Alex W]

Paul,

I did this job last year and found it to be very straightforward.  I did it without any 'special' tools like a flare nut wrench or crows foot.  The injectors I installed with a torque wrench and torqued to spec... the compression nuts on top were done by feel... you'll loosen them again to bleed anyway.  I figure as long as they're not leaking they're fine.  Note that a crow's foot does not work on a torque wrench; in that the torque setting will not be accurate because the center of effort is offset.

I also ordered new injectors online from a Kubota dealer... about $10-$15 more a piece that having them rebuilt but turned the whole thing into a one evening 3 beer job.

[britinusa]

Thanks Alex, I'm going down to the boat today to measure the wrench sizes.

We have a Kubota dealer literally 10mins from our house and they have been very helpful on several occasions.

I already have the beer! 

Paul

[KWKloeber]

 Paul,

Do you have the KB part numbers? If not I can look them up or copy the parts page to you later on today/tonight.

k

[KWKloeber]

PS. You can also get the parts aftermarket for a savings over the KB list prices.

[Stu Jackson]

http://c34.org/wikiwp/?rdp_we_resource=http%3A%2F%2Fc34.org%2Fwiki%2Findex.php%3Ftitle%3DManuals

has the Kubota non-marinized parts list.

[Ed Shankle]

When I replaced my injectors I had to remove the valve cover, otherwise there wasn't enough room for the socket wrench to fit over the injector base. The wall of the socket was too wide. Probably could have found a thinner walled socket, but rather than run out again to the stores looking, I just took the valve cover off.
I also found a pile of carbon dust under each injector after removing them. I assume it fell off the injectors when I took them out. I vacuumed the dust out. So having a vacuum handy when you start the project might save some annoyance.
Regards,
Ed

[britinusa]

Good points Ed.

When I purchased the Injectors yesterday, I asked if they had a tutorial on how to do it. 'Tommy' took me to a display mounted engine and showed the process.

He advised that there would probably be some carbon build up around where the injector screws in and to wipe it off using a kitchen scrubber (green thing) to remove it.

I'm heading down to the boat to make sure I have all the tools before starting the job. Once ready, I'll photograph all of the steps for posterity.

BTW, 'Tommy' said it was a very reliable engine that could be rebuilt forever! Dry Cylinder liners were easy to replace and the crank shaft could be ground and new, smaller bearings installed. He has 20+ years of working on them and in sales of their parts.

Paul

[Ron Hill]

Paul : You could have saved yourself a lot of guessing if you had looked in the Mainsheet tech notes.  I wrote an article and listed all the tools and step/checks needed to pull/reinstall the injectors.

With all the information published in the Mainsheet Tech Note for the last 30 years, why would you think you're the first one to take on ANY task????  Look there first and then in WiKi!!! 

A few thoughts

[britinusa]

Ron, I have read dozens of articles in the tech notes about the injectors, but did not find your article.

Is there an index that would narrow down the subject?

Paul

[KWKloeber]

Paul the index is right above the "years listed" linked off the main homepage 'tech" link

http://c34.org/tech-noteswp/


i.e.,
http://c34.org/master-index/


Or the home page search box, also searches the tech articles.

Note injectors *should be* metric-sized wrenches, Kubota used no imperial sizes. 
The only imperial sizes are the Universal "add-on marineizing."


kk