Injector Pump
 

How do you test a Injector Pump 1987 300D

It would be better if you just told us what problem you are having that may be caused by the Fuel Injection Pump.

There is 2 systems on the Fuel Injection Pump. There is the Fuel Supply/Lift Pump bolted on the side of the Fuel Injection Pump. The Fuel Supply Pumps the Fuel from the Fuel Tank and supplies it to the Fuel Injection Pump.

The Fuel Injection Pump supplies high pressure Fuel to the Fuel Injectors. When the test the Fuel Injection Pump in a shop the put it on a special made and very expensive Test Stand and check the calibration of the Fuel Injection Pump compared to the Bosch specfications.

do you know how to remove the supply pump from the side of the assembly? I think mine has failed, it barely runs and there's no bypass fuel coming through at all. Is it repairable or do you need to replace? thanks.________
VAPORIZERS

After you remove the exterior Fuel Lines I believe there is only 2 (3 on my year and model) nuts or bolts that hold it in. Just back them of a little and go to the other side and back it off a little and alternate like that until it loose and it easily pulls out.
The reason for alternating when loosening and also when tightening is that it may be under Spring Tension and it can crack the Flanges if it gets cocked (the cracking more likely to occur when installing the new one).

Are you sure that the Fuel Tank Screen in the Bottom of your Fuel Tank is not restricted or plugged?
I have also assumed that you changed the little Primary Filter.
I am not sure if your year and model has the Primary Filter attached to the Fuel Inlet Hose or you have the one that goes into a spot that is built in to the same Housing that the Secondary Spin-On Filter screws into.

OK thanks for the info. I wonder if it is possible to fix it, ie replace seals or o-rings or something like that? Or maybe I have to get another from the junk yard, probably should anyway and maybe recond that one b4 swapping them.

Also if you remove it, does it need a new gasket? Ie if I remove it maybe I can't put it back and drive the car unless I have a new gasket ready. But these merc's usually seem to have rubber seals rather than paper gaskets, eg the thermostat.

Re your other querie, I actually have a veg oil conversion. It barely runs on diesel without any fuel coming out of the by-pass, but doesn't run at all on veg - I think it must be borderline and can barely pump enough of the thinner diesel to feed the injection pumps - I just read on this forum somewhere that 95% of the fuel bypasses the injectors and is returned, so it must be barely working.
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GM 60-DEGREE V6 ENGINE

There is sort of a rebuild kit for the Fuel Supply/Lift Pump; it has 2 plastic Valves and 2 valve springs in it. What is missing is the tiny O-ring that does not come in the kit.
However, You can take your Fuel Supply/Lift Pump a part and see if there is any thing gunked up inside or if the little Valve Springs are rusted through.
You will need a 30mm Socket or Wrench to remove the large Hex Plug on the side of the Pump so you can look at the Pump Spring and see if it is broken.
The other Plugs I suggest that you remove and deal with one at a time.
The Copper Washers can be reused if they are not too mangled by hanging them on a wire Coathanger and heating them Red hot and letting them cool; that softens them.

If you remove the Fuel Supply/lift Pump you will most likely need a new gasket because it is rather thin and my rip when you remove the Pump.

You might disconnect the under the Hood Fue Inlet Hose and get an other length of Hose long enough to run into a searate container of clean Diesel Fuel. Pump with your hand primer to prime the Fuel Supply System and see how much Fuel you can get out of your Fuel Supply Pump like that. If you get a good amount out it is likely you have something plugged up.

That's a good idea to try feeding the fuel from a can - might as well make sure it is not starving fuel b4 the pump, before removing it and opening a can of worms. Both systems (diesel and veg) are not working properly so it would seem like a big coincidence if they both failed at once, but you never know given Murphy's law which seems to dog me incessantly. Great idea with the bit of home metallurgy to re - or would that be de-temper ? - the copper washers.

Where do you get the recondition kits, from the dealer? What is the tiny O-ring for? hopefully not the main seal for the pumping mechanism...
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Honda Cb-1

The heating a Copper Washer till red hot and cooling it idea so that you can re-use it came from a Navy Machinist Mate Manual owned by one of my past Boss.

In the Fuel Supply Pump there is a Roller Tappet that pushes a about 5mm thick shaft. The O-ring seals that shaft (the later model Fuel Supply Pumps with no Hand Primer are different). After that there is no other O-rings on the Fuel Supply Pump.

PeachParts sells the Valve kit for around $11 and what ever the shipping charge is.
The Dealer also sells it. But, no little O-ring in either kit.

If you want the complete rebuild kit (with all of the parts, O-ring and Copper washers and ect.) for the Fuel Supply Pump (there is a number plate on it) take it to the local Bosch certified Fuel Injection Shop and ask them if they would sell you one and for how much.
I believe the Fuel Injection Pump to Fuel Supply Pump gasket also comes in the kit but I would ask to be sure.

It took a while to find the below thread; there is a pic in there showing the little O-ring and other stuff.

I tested the pump from out of a can today, and got the same result so that eliminates "upstream" problems. Also I can squirt fuel out of the by-pass hose (that clamps to the top of the spin-on filter from the engine side of the fuel distributor/inj pump) with the primer pump, so that suggests the by-pass is working OK too. The surprising thing is that it seems to be running on diesel by the injection pumps alone (I assume there's one for each cylinder), although not too well.

Now that I have a better idea of the lift pump I'm leaning more towards thinking it might just be a failed, probably clogged valve. I don't know how the actual pump piston is sealed but it was a sudden failure so doesn't seem like a failed pump mechanism unless there's a piston seal that can suddenly fail. Anyway I'll aim to take it off tomorrow.

I can't find the valve kit on peach parts, they just seem to have the whole lift pump for about $250. Should get a gasket from a dealer I suppose but it's far away. I could just get gasket paper and cut it out.

The Piston inside of the Pump has no Seals. It is just a close tolerance "slip fit" metal to metal.
I have seen the Spring Break on them and I have also seen where grit or rust causes the Piston to stick and not move.
However it is more likely that there is something gunking up the 2 valves or under the Valve seating area. The springs on the Valves are not very strong so they cannot seal if anything thick or gummy gets under the Valve seats.

The Pic on the left shows the Pupm Piston and Spring. The Pic on the Right shows the Roller and Tappet, Rod and the little O-ring that goes in a groove inside of the pump Housing. I do not have a pic showing where the Valves go.

I got one from a wrecking yard yesterday ($20), put it in today, and nothing! CAn't even get the hand pump to work anymore. Looks like good old Mr Murph dogging me again. I mean you can't expect good parts from a yard all the time, but this seems like a very rare failure. Anyway I had a look at the old pump, it seems there's no spring pressure on the pump piston at all it's just loose, so must be a broken spring I assume - unless the spring is not very strong and can be gunked up in compressed position. Got one of the valves out and the spring was gunked up so I freed that up, couldn't get the other fitting off yet it's as tight as something rude. Anyway I'll take the "new" pump off again tomorrow if I have time, I don't recall that the piston was loose so probably it has valves that need a clean-up. If necessary I can use ones from the old pump.

As far as the O-ring goes, I wonder if I should try to replace while I'm at it. Hopefully this is a rare failure even for the whole life of the car, although you'd think it would probably fail after 30-odd years. I might just leave it for now, especially since it's another problem finding a new O-ring. I could replace it with one that looks right and actually cause a problem, so I may just wait until it fails although that might be hard to detect until it gets pretty bad.
HOpefully both valves are a bit easier to open up on the replacement pump.
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Cb1300

I have seen Pumps where th Piston compressed the Spring and stuck like that. You will not know until you remove the 30mm Hex Plug.

If the thing Copper Crush washer on the 30mm Hex Plug remains in the Housing do not try to pry it out as it will get too buggered up to reuse if you do.

However, since you discovered that one of the Valves was gunked up what does that tell you about your Fuel?

I got the other 19mm fitting off today, with aid of a new socket set from Pepboys, and a slightly skinned knuckle when it finally gave. They didn't have a 30mm socket, they had a bigger one I think 33 or 35mm, and 1 1/4 and 1 1/8th sockets. I think it would be in between so not sure if either the metric or the imperial sockets would be a good enough fit.
I'll have to take the other pump off anyway so can probably avoid removing either of the 30mm's. I lightly sanded the plastic valve faces with some 800 grit sandpaper (on a very flat surface of course) to get the scoring off, and found they seal much better now - you can test them just by blowing and sucking on the fittings. Not quite perfect but I suspect they don't have to be. I also pressure tested the O-ring and it is totally sealed. The ring only creates a light drag on the push rod, but obviously it is enough.
If I can't get either one to work I have the option of putting an electric pump inline just before the input, which would be an interesting experiment and you can get them for about $30.

RE fuel it's been a learning process with the filtered waste veg oil. For one summer I wasn't even flushing before switching off since it was running fine and even starting on the veg. But started having blockage problems then, probably from the oil sitting cold in there and some waxy type of stuff precipitates out. Something was really jamming closed for some starts, probably a valve. I've since been more careful with flushing, and also nearly always use oil from a seafood place which is a lot cleaner, so current gunk is likely left over from back then but I'll up the flushing a bit.
But there's definitely a price to be paid for using WVO but it sure isn't at the gas pump, so it's well worth it so far, and quite a good hobby as long as you don't mind getting your hands dirty and can do your own tinkering with the system. A bit riskier on a more valuable vehicle since there's the chance of it shorting the life of the engine. In that case I think I would be more stringent with the bag filtering (ie 0.5 micron if possible), flushing and preheating system. My merc is so rusted underneath that it is practically ready to fold in half under there.
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Honda Wave series specifications

Got the yard pump off today, nothing wrong with it. BAck on and it's running fine at last and back on free fuel.
I blew and sucked on the inlet and outlet lines and the valves are working perfectly, took out the input valve and it's very clean, virtually no scoring. I think one of the valves must have been stuck open from sitting for a long time and until I sucked on it there was no good reason for it to free up. probably could have just sucked on the input line without taking off the pump, or could have pushed fuel through it somehow - once full of fuel the pump would have probably freed up the valves - put it down to experience to check the valve function before installing. O-ring has even less resistance to shaft movement than the old one (more like feeler gauge resistance when the adjustment is right) but still seems to be sealing perfectly. Not sure how to get the o-ring out anyway without damaging it, or put it back in without risking it falling into the pump chamber.
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Oregon dispensary