Hello All, Thanks in advance for any help. Nice wet Spring here in Colorado. I was trying to fix a bad spot in the road last week when I had a noticeable lack of power. I carried on anyway and it soon stalled several times then refused to start. Been a long time since a filter change so figured that was the issue. After bleeding the system she started reluctantly then died under a strain and would not restart until I gave her some ether. Managed to limp home, could barely climb the 12% grade. I am waiting for this snow/rain to stop before getting out the wrenches. In the mean time I have been reading other peoples woes and fixes and have learned quite a lot. So, I am worried it is the injection pump (the pump is not yellow so at some point someone has replaced it). Can anyone help me eliminate all other possibilities? My plan at this point when the weather clears is to make sure I have good flow from the lift pump..... blow out the line between the lift pump and the tank....pull the return line from the injection pump and look for any crud there...... then come back here to see what other ideas anyone might have. Roy
Good plan... be sure to pull the outlet fitting out of the pump that the return line connects to, in addition to blowing the return line clear to tank, be sure there is no black or brown fibrous material in the outlet check valve, there's a small spring and glass ball in there. If you find material in the check, the pump needs work.
YUP.. just remove the return line AND THE ENTIRE FITTING from the top of the pump.. Start the engine and see if you have full RPMs and power.. Then blow out the return fitting w/ shop air.. reinstall.. if it clogs again you have pump problems.. IF its in a spot that you cant live with.. remove the fitting again and smash the glass ball and spring out and reinstall.. JUST REMEMBER>> all those plastic pieces are going back to the tank.. and get the pump repaired.. eventually, BAD THINGS are going to happen if you don't.. engine run-away, pump coming apart internally..
ok thanks for the input. have heard of this fibrous washer that turns to coffee grounds. any suggestions on a good site that will tell me about pulling the injection pump and getting the timing right when I reinstall? Roy
I've used this outfit to rebuild my pump. This link is to their site http://www.dandcdiesel.com/removal-and-installation-tips.php
Put a tee in the fuel line between the transfer pump and the injection pump, then run a line into a pressure/vacuum gauge in the cab. If it has the same pressure when stalling as it does idling, then the injection pump is the problem (as long as the inlet to the injection pump isn't plugged, and the return fitting is removed) If you pull the pump without insuring fuel supply, it will do the same thing with a new pump.
OK I am confused now good fuel from tank to inj pump pulled the entire fitting from the top of the inj pump and there is no ball check there. Started raining on me so gave up without blowing out the return line to tank What about this ball check? Any suggestions? Pump model # is H2 DB2-4938
I like this Any idea what sort of fuel pressure I should expect? Going to town tomorrow and can get the fittings and gauge.
NO BALL?? That's a red flag right there.. I just pulled the parts list and FO' SHO' theres a check ball and spring.. in the return connector. You need to get out the compressor and blow back the line, from the return on the pump .. back to the tank.. REMOVE the fuel tank cap FIRST.. On another note>> DELMER IS CORRECT.. a bad lift pump will give a similar problem.. "normally" you can check it by loosening the inlet line going too the back of the injection pump and just spinning it over.. IF it squirts you in the face.. Lol.. its pretty much a given, its good.. BUT.. nothing beats a good old fashioned fuel/vac gage.. to be absotutley sure.. just makin fun Delmer.. but yeah, your right..
Looking at the exploded view here...... http://www.biotrieb.org/fileadmin/u...B2_Operation_and_Instruction_Manual_99009.pdf (it is about 4 pages from the end) This looks like what I have, just a connector that screws into the top cover of the pump has an o-ring seat and a small diameter passage through it. nothing that looks like it would hold a ball check/spring. Am I missing something? Going to get the compressor out now and make sure the return line is clear.
Page 12, item "G" says 1.7 at the bottom of the page. "Housing pressure is maintained by a spring loaded ballcheck return fitting in the governor cover of the pump" That's item 27 in your exploded view.
Say you have some junk floating around in the tank, or the inlet screen is partially plugged up and runs until it collapses... There's no such thing as absotutely sure
" am I missing something".. yeah.. the check ball.. LOL To be SURE about the pressure.. do as Delmer suggests.. and or.. shut off the fuel.. remove the side cover on the inj. pump.. hold a wad of paper towels under the fuel that comes out.. any black plastic pieces are flex ring.. BUT, then again.. you might not get any seeing the ball has ALREADY been knocked out.??? and your symptoms mimic a clogged return line..
Okay... you get to laugh since you are willing to help. I REALLY do THANK all of you for the help! Delmer, it looks like the time, effort and expense of parts to diagnose and hopefully tell me I need a lift pump will be nearly what a lift pump will cost. (not to mention that the parts place is nearly an hour away and I NEVER get it all on the first run). So I ordered a lift pump, should be here tomorrow. Since the lift pump is yellow and the inj. pump is not I am assuming the inj. pump has been changed since the '80s and the lift pump not (and yes I know what they say about ASSUME). Now Pumpman and Lantraxo, I went and blew out the return line (all clear) and triple checked that fitting and I see no way I could be missing this ball check. How tiny is this thing? the orifice through that fitting is smaller than a pencil lead. There is nothing in it, it looks to be a constant diameter and I can blow both ways and see daylight through it. Hopefully the lift pump will do the trick but now I am freaked about this ball check. I will let ya'll know Thanks again Folks Roy
Just because the injection pump was changed, doesn't mean it was new, rebuilt, or upgraded. It could have been an original from the junkyard, and it might not even have been needed? What's your fuel level? Have you ever noticed symptoms before at low fuel level? The fuel pressure test is handy because it eliminates half of your potential problems, it's either upstream or downstream and you can go from there. A pro like pumpguy can recognize the way it's acting and be pretty confident in his diagnosis, from here I can't even catch obvious jokes... The fuel pressure should be something like 5PSI, but the main thing is that it stays steady at idle vs stalling at full load.
Wanted to put a final post to thank all that helped and let anyone that stumbles on the thread in the future know what the outcome was. I swapped out the fuel lift pump after making sure the supply to it was good, this was about the same cost and a bunch less hassle than installing a gauge. No Joy there. So I pulled the injection pump and sent it to Mike "thepumpguysc". Once he had the pump he quickly gave me a very detailed summary of what was wrong, what it needed and what the cost would be. Once he had my approval he got the parts, repaired the pump and got it back to me in a very timely manner. I put it on this morning and the thing started while I was still bleeding it. So I am back in business. Thanks to the forum and it's members and to the pump guy!