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opwan2002 · 26-05-2012, 20:54

Has anyone removed injectors from this model Yanmar, and are there any special considerations? I'm taking the injectors to the yanmar dealer for rebuild, but was wondering if the removal of the injectors was a job that I might be able to do on my own. I am a moderately capable mechanic, I mean if I take it apart I can put it back together. I know how to bleed the system once I get the injectors back in...Just read a couple of threads with warnings about possible visits to hospital due to pressure release etc. Any comments before I dive into this job would be appreciated.
The reason for the injector rebuild-black smoke at running temp. Checked air intake, had the exhaust elbow and coolers boiled and the reinstalled. Not a shaft entaglement issue. Last time I was out I also experienced a fluctuation in RPM. I don't think it was a dirty fuel problem...Anyone else have similar issues and what was the problem? I don't want to get into the fuel pump unless I have to.

impi · 26-05-2012, 20:59

http://sagaforumet.com/yanmar-manual...JH3-manual.pdf

Download the entire engine overhaul sevirce book

opwan2002 · 27-05-2012, 08:43

Thanks for the link,but I'm looking for someone with hands on experience to offer up a few pointers.

opwan2002 · 27-05-2012, 17:45

> IMPI... thanks for the link to the electronic manual for Yanmar 4JH3-HTE, however I mis-printed my engine model it is 4JH2-HTE. If you have access please send me a link to the correct manual. I have the printed owners manual, but an electronic copy would be great! Thanks.

impi · 27-05-2012, 20:38

Quote:

Originally Posted by opwan2002

> IMPI... thanks for the link to the electronic manual for Yanmar 4JH3-HTE, however I mis-printed my engine model it is 4JH2-HTE. If you have access please send me a link to the correct manual. I have the printed owners manual, but an electronic copy would be great! Thanks.

will have to see if I can get that for you ... otherwise drop a line to Kent at Just Catamarans ... kent@justcatamarans.net. He is a very helpful fella and I am sure he will give you a run down on removing these injectors

impi · 27-05-2012, 20:47

http://www.dieselhub.com.au/yanmar_m...E%20MANUAL.pdf

impi · 27-05-2012, 20:56

check out bottom of page 3-36 under trouble shooting for exhaust smoke.

**bstreep** · 29-05-2012, 21:43

Before you take out the injectors...

Do you get black smoke at higher RPMs, and can't get over about 2800 rpms? If so, I'd look at your turbo (you are turbo charged, right?).

I removed ours last summer. Seems I was a bad boy and didn't run the heck out of it like I should have. It carboned-up. About an hour to remove, same putting it back in - but like a giant Chinese puzzle. Cleaned it with EZ Off oven cleaner - not the "green" stuff. Works like a champ.

opwan2002 · 30-05-2012, 07:01

Negative Ghostrider...Mine smokes from the minute I fire it up and while operating at temperature (basically all the time) there appears to be some post operating drip as well. I run it hard at least once a week, and recently had the coke boiled out of the exhaust elbow. While I was in there I checked the turbo and Air intake for blockage. Just don't see what else it could be, unless someone else has a different diagnosis.

Buttercup · 10-06-2012, 19:29

I pulled the injectors on my 4JH2-HTE recently. I wasn't having issues, but just wanted to have them checked and cleaned. The injectors come out pretty easy, but if you have any corrosion, you just need to be persistent with them. I used PB blaster to loosen up some corrosion. I'd spray some around the base and let it sit. Then would rock the injectors back and forth a bit until they loosened and eventually they came out.

You might find that the Heat Protector stays in the injector hole. You have to remove it with a pick. I cut some sponges to fit in the injector holes so I could clean up some corrosion in the area.

When you put the injectors back in you need to use new heat shields. My injector shop provided them when I picked the injectors up.

Make sure you use a torque wrench when you put the nozzle retainers back on. Check your shop manual, but I believe the spec is 30 ft lbs.

Good luck!

**Charlie** · 10-06-2012, 20:01

Soak the retainer nuts in penetrating oil overnight. Make sure that fuel is shut off. Run engine till it dies. Remove the hardlines. Mark which one goes where. Loosen the nuts on the injection nozzle retainer. If the injectors come out that is great if not turn the engine I use a wrench some people just hit the starter. The injectors typically pop right out.

opwan2002 · 11-06-2012, 06:41

>Buttercup & Charlie:
Thanks soo much for your input. Even after you read the manual, I've dug unsuspectingly into projects only to be pumeled by inexperience. Your help will make all the difference. I really appreciate it!

SailorHarry · 05-08-2012, 07:16

When you take off the high pressure lines to each injector, use masking tape to cover the ends of the lines to keep any trash out. You will have to slacken the nuts on the fuel injection pump ends of the high pressure lines, and for that you will need a crowfoot wrench (Sears sells a good set). Back off the hold down nuts on each injector. If the injector is free, just pull it out. If it is stuck, squirt some Liquid Wrench or WD 40 around the base of the injector and try again tomorrow. If still stuck, WITH the hold down bracket on the injector still in place, but with the nut slacked off perhaps a quarter of an inch (no more) hit the starter and the compressed air will bump the injector loose. Plug the injector holes with cloth or paper towel to keep junk out. The previous posts tell you to remove the heat shield, etc. Spot on. Good luck.