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pk99red
01-04-2009, 07:32 PM
"Hi
we have TAMD31A,B engines in our 32' explorer, our starboard engine is exhausting quite a bit of raw fuel out into the water any idea's what avenue we should check here, also the small primer level on the fuel pump doesn't want to pump we have tried turning the engine over a bit to get it to hit on the cam ect that works on the port engine when it doesn't catch because of this we can't prime the fuel filter makes it a little harder to bleed

Thankyou for any help on these problem's

Keith"

cbaymac
06-25-2012, 03:28 PM
I know this is an old post, but did you ever find a solution? I have an Egg Harbor Cruiser with the same issue and believe it to be a clogged fuel injector, but not sure if there is a way to pinpoint the faulty injector without pulling them all. They have less than 100 hours on them since new. Again the fuel is in the water of the exhaust and therefore a potential environmental issue. The fuel is not int the radiator water. Thank you.


"Hi
we have TAMD31A,B engines in our 32' explorer, our starboard engine is exhausting quite a bit of raw fuel out into the water any idea's what avenue we should check here, also the small primer level on the fuel pump doesn't want to pump we have tried turning the engine over a bit to get it to hit on the cam ect that works on the port engine when it doesn't catch because of this we can't prime the fuel filter makes it a little harder to bleed

Thankyou for any help on these problem's

Keith"

glen_adolph
07-01-2012, 02:05 PM
A way to isolate a faulty injector is to loosen the fuel line on each injector, (one by one, engine running) and listen for the engine to change. The engine should change, if not, you found the bad injector. Hope this helps.

cbaymac
07-01-2012, 02:40 PM
A way to isolate a faulty injector is to loosen the fuel line on each injector, (one by one, engine running) and listen for the engine to change. The engine should change, if not, you found the bad injector. Hope this helps.

Thanks for that info as well on locating the bad injector. I tried using an IR Thermometer and trapping the injector down with a screwdriver. Both methods worked. The IR Thermometer is useful in that you do not have to remove any engine components to test. This is a link to the video I did this morning. We found two bad injectors. More video to follow once the injectors are replaced.
http://youtu.be/7c_nFoYucH0
Thank you,

cbaymac
07-01-2012, 05:30 PM
Thanks for that info as well on locating the bad injector. I tried using an IR Thermometer and trapping the injector down with a screwdriver. Both methods worked. The IR Thermometer is useful in that you do not have to remove any engine components to test. This is a link to the video I did this morning. We found two bad injectors. More video to follow once the injectors are replaced.
http://youtu.be/7c_nFoYucH0
Thank you,

Now that I have the bad injectors out, is there a good/cheap way to clean them? They are less than 100 hours since a new rebuild. Soak in carburetor cleaner overnight? I hate spending $100 on a rebuild injector exchange, but do not have the tools to take mine apart. Someone has said to run these DD up to full power once an awhile to keep the carbon out of the cylinders...I think I am becoming a believer instead of my normal 1800 RPM cruise. Any thoughts on keeping the carbon down?
Thank you,

glen_adolph
07-01-2012, 07:48 PM
You could try an ultra sonic cleaner from Harbor Freight. I would try to find a diesel injector pump shop (Bosch), and have them clean and test your injectors. They should be able to do it cheaply.
Also, engines like to be run! Bring them up to operating temp often and WOT once in a while.

cbaymac
07-02-2012, 01:58 AM
You could try an ultra sonic cleaner from Harbor Freight. I would try to find a diesel injector pump shop (Bosch), and have them clean and test your injectors. They should be able to do it cheaply.
Also, engines like to be run! Bring them up to operating temp often and WOT once in a while.

I appreciate your comments, Thank you. I did see a YouTube using the UltraSonic cleaner. They are around $30 at Harbor Freight or Amazon...certainly worth a try. I have also heard it is good to run the engines WOT at times. Now I can see why. Lots of carbon build up if you don't. Is there anyway to Pop test the injectors without having to buy the high dollar tool?

stringer_bell
07-02-2012, 06:22 PM
No, pop test requires bench tool with gauge and handle, and test fluid, so that you can pressurize the injector one at a time, and watch the spray pattern and at which pressure it opens up. Not sure how expensive the tool is, but it is the only way to test them. I pop test all injectors before I decide which will go to the cleaning or tip replacement or whatever additional work needs done.

glen_adolph
07-02-2012, 06:47 PM
An injector shop should pop test your injectors for free. If they only have 100 hours on them, they should just be dirty.

cbaymac
07-06-2012, 05:42 PM
Was an interesting day. Had figured out the bad cylinder. 1. IR thermometer said the cyl was colder than the rest. 2. Trapping the injector down with a screw driver and no difference in rpm...and the exhaust clears up. So bad injector right? Wrong. Not really sure, but I swapped two injectors and the problem remained at the same cylinder...so? Bad exhaust valves? There is no blow by or evidence that the piston and rings are the problem, but it must be low compression since the cylinder does not appear to be firing. Any thoughts on what is wrong? Second question. Can I somehow bypass the fuel to that cylinder for a short term solution? Putting a cap over the inlet to the injector would seem to be risky do to no fuel input to cool the injector. Is there an easy way to trap the injector in the down position? Thanks, have a great weekend.

glen_adolph
07-06-2012, 07:06 PM
You can plumb the injector supply line into the return line with a hose and fitting. I don't think it would hurt. Another test you can do is called the cylinder leak down test. It is simply pressuring up the cylinder with air when it is in the combustion stroke. Listen for air leaks. If air is comming out of the blowby, it is the rings. If air comes out the exhaust, suspect exhaust valves. Intake= intake valves. Radatior=head gasket. I would recommend pulling the valve cover and checking to see if you have a stuck valve. The best solution would be to remove the head, send it to a machine shop for a pressure test. Inspect the cylinder walls and install a new head gasket.

cbaymac
07-07-2012, 07:20 AM
Great tips, thank you. The cylinder leak down test sounds like the next step. I'm taking her out today and will try some wide open throttle. I just updated the YouTube video...seems I know a lot more about injectors...but now that is not the problem :( http://youtu.be/unbujXnwMcg
Cheers,

glen_adolph
07-07-2012, 10:36 PM
Great tips, thank you. The cylinder leak down test sounds like the next step. I'm taking her out today and will try some wide open throttle. I just updated the YouTube video...seems I know a lot more about injectors...but now that is not the problem :( http://youtu.be/unbujXnwMcg
Cheers,
I saw the video and your Pop test was not conclusive. The injector should hold pressure until a certain pressure is reached. Also, cylinder temperatures will be slightly different depending on the circulation pattern of the cooling jacket and oil flow passages. Usually #4 or #6 cylinder overheats first. You can do a leakdown test is you want, but the answer will be the same. Pull the head. Whether you have a bad or leaky valve, blown gasket, or broken rings does not matter. Hope this helps.