I've had my 1978 240D down for about 2 months waiting for the new head to get here. We installed the new head and now have tried to start the car without much success. The injection pump does nothing . I cracked the injector lines and the fuelfilter is full. I've pumped till I'm blue in the face it will fire off with starting fluid but will not prime the pump. Does the fact that it was down for so long that the injection could have been harmed somehow . Iam a gas vw mechanic and this is my first diesel valve job . Please someone help!

Dennis:

Please, please, please, please DON'T use starting fluid! You will break the ring land on the top compression ring and destroy the cylinders!

The injector pump has bled down and is full of air -- crack the return line on the side (don't take it off, just loosen it!) and pump the priming pump until no more air comes out. There is also a bleed screw somwhere on the top of the pump -- if you can find it, loosen that instead and pump until no more air comes out. I'd presonally replace the priming pump if it is still the old "unscrew and pump" type -- the leather goes bad and it leaks rather than pumps!

Once the IP is full of fuel, loosen all four injector lines at the injectors and crank the engine, accelerator to the floor, until no more air comes out. You may want to take the glow plugs out while doing this so the battery lasts longer.

You will need to hold the accelerator all the way down while cranking, or it will take three or four battery charges to get started! Takes forever to get all the air out and fuel all the way up!

If you replaced the fuel filters, it takes several hundred strokes on the priming pump to fill the main filter -- take it off and fill it with fuel -- if you have the older style "sock" filter that goes into a cast canister, for sure fill it with fuel. Saves an incredible amount of cranking.

Hang in there -- nothing is wrong but dry pump! It took a couple battery charges to get my brother's 300D started after a rebuild, and the fuel system was full except for the injection lines!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Peter,

Thanks for the input. We will follow your instructions and hopfully report back that this fine car is on the road again.

Still have not been able to get this thing to fire up. Have pumped and primed and turned engine over thought 2 battery charges and no success.

When we use the priming pump it doesn't seem like any fuel is going into the IP. But we know that the priming pump is working.. if we loosen the 'in' fuel line at the IP and pump, fuel comes out.

What is the fuel capacity of the IP?

Also.. there is a can on top of the IP back of the injector lines. Some kind of Vacuum unit? I don't have a vacuum line to it.. didn't have one before we took the head off.. ( have pictures ) and don't see any line to connect to it. Am I missing something here?

What am I'm missing or doing wrong?

Dennis:

Loosen the return line from the IP at the fuel filter and see if you have fuel there. The IP holds about 100 cc of fuel, and if this is all air and you aren't getting enough pressure from the priming pump, you won't get fuel to the injectors.

Do you get fuel out of the injector lines with the cap nut at the injector loose? If so, you have fuel in the IP and all is cool there. Of course, this means you have another problem......!


Check to make sure that fuel comes out of the IP on the return side before you do anything else. You should have significant resistance at the priming pump -- if it is easy to pump, it may be bad and not developing any pressure.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Peter,

I did loosen the return line from the IP at the filter... got a little air bleed off then fuel. However I've never seen any air or fuel come out the return line connection at the IP. ??? that.

After priming and priming until my hands are tired...turning the engine over and over... now with the injector fuel lines loose at the IP I noticed fuel resting on top of the IP ( noticeable around 2 & 4 ). That makes me think that fuel is passing through the IP. So... I've got the injector lines tight at the IP and loose at the injectors now. I've actually seen fuel spit out the #1 line at the injector but none of the other lines yet... have the battery charging again at this point.

I might be getting somewhere.

Dennis

Dennis:

You are indeed on the way. I also suspect your priming pump isn't totally up to snuff. Even with a good one it takes forever to pump the IP full. I've run the 220D out of fuel twice -- only got it started the first time because I filled the filter, and I have a new pump.

Some IPs have a ball and spring pressure valve, some have a bleed orifice in the banjo bolt. If there is a ball and seat, you aren't getting enough pressure from the hand pump to lift it, hence the lack of prime in the pump. The orifice is easier, since it will slowly bleed off the air. The problem is that the return is lower than the plunger fill slot, so the air stays in the top of the pump forever, and the injection volume is small enough that many, many cycles are required to purge the air through the plungers.

You should start to get some help cranking from fuel injection once you've got fuel in a line -- if #1 has fuel spilling and no air (remember to floor the throttle!), go ahead and tighten it so that #1 will start to fire -- speeds the engine up a bit and takes the load off the battery.

Once it begins to run, keep your foot in it until you get most of the air out -- it will run rough for a while.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Dennis,

You never talked about timing of the IP after the rebuild. You have done the start of delivery adjustment haven't you?

Good luck,

Larry,

We only reworked the head and not the lower half. Marked the timing chain and cam.. sprocket etc. so that when it all went back together it went back together the same as it was when we opened her up.

We took pictures as we went along to help when it was time to put things back. The trick was we had the engine a part for almost 2 months... it took awhile to get the head checked to see if it was cracked... it was so... locating another head and having the valves done then getting the head shipped here ( I live on Kauai HI ) . Anyway..

I couldn't figure out why when we loosened the connection at the IP return line to prime the IP until no air came out but fuel ( as Peter said ) that I never saw any thing.. air or fuel never would come out of that connection. Reason???? we overlooked the fact that the 'in line' connection banjo bolt and the return line banjo bolt are different lengths. We had them reversed! As soon as we corrected that ( minor detail ) the car was running in about 5 minutes.

Peter and Larry... thanks for the help and suggestions.

Dennis

Dennis,

I understand the delay of getting parts and getting it back together. My daughter's car was apart over two months due to delays in getting parts and getting things out of the machine shop, not to mention my European trip falling right in the middle of the whole project.

I love these cars, but you can't just run to Auto Zone and get whatever you need.

Glad you got it going,

Dennis:

Better than that, the return line bolt only has a small bleed orifice in it instead of the large hole in the supply bolt -- you weren't delivering any fuel to the IP!

The bleed holds the IP at about 15 psi (I think, not sure) to fill the injection elements when the sleeve valve opens.

I never thought of reversing the bolts -- I'd not have taken them off, I don't think.

Glad you got it started, and there wasn't anything serious wrong.

I know all about delayed projects -- my brother has his 300D in my garage -- the floor pan repair we started last October turned into a complete body restoration! We hope to be done this winter, he wants the car back!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!