If your engine has a separate mechanical lift pump like I think you have, then the pre-filter is before the lift pump. You cannot pressure test the secondary fuel filter from the pre-filter. You must pressure test it after the lift pump.

If you cannot see bubbles through the aged brown line, replace it with new or splice in a clear section so you CAN see.

Indeed I did pressure test before the perefilter my reasoning as when I had a separate fuel supply suspended from the ceiling 3 feet above fuel freely flowed through the return line into my catch jar. I simply pinched the return line and applied 20 lbs for 20 minutes then had the bright idea to test 30 lbs and that blew off the injector return line from the recirculating line back to the filter.

Today I'm cutting the clear lines and splicing in a independent pressurized fuel system, garden sprayer with a small 5 micron filter. I'll try befor the main filter first then directly into the ip.

Wish me luck p.ease.

Ok I believe I found the cause by accident of course. I carefully began bypassing one item at a time and I installed new rubber hoses as I went along first fuel heater, then lift pump with a pressured independent fuel source complete with filter, then finally once I bypassed the filter and feed directly into the ip it ran like it should. I had new clear lines so I thought best to reinstall them actually a very easy process using clear motor cycle fuel hose and a heat gun. While I was installing the bango directly above where the return line connects to the filter I noticed it was loose. This explains a lot when it sat for a few hours the filter bled itself of air hence the good running for 45 seconds. I'm guessing the shake and vibration of a running engine changed this into a source of air which is why air was in the fuel? I have no explanation why a pressure test would not detect this unless like someone else said you can't pressure test through the lift pump which I have other thoughts. I suppose my lesson has been that return is just as important as the source. After I get new crush washers I am hoping this will be the end of this adventure. Stay tuned I'll update one way or another.

If you have a torch, you can recycle the copper washers. Hang them on a small piece of wire, and heat them to glowing orange with the torch (be careful not to melt them). Allow to cool, clean off the oxidation, and they are now soft / malleable again and can be re-used.

The only change now is that after it starts it runs rough right from the beginning not after the 45 seconds. Once the engine temp gets to Round 60 no smoke and smooth idle no smoke. Or when i manage to get the revs to around 1500 and above no smoke cold engine. After the engine has warmed upto 80 its and shut off the restart stupid smoke rough idle for a few minutes then ok. I see no air bubbles in the supply line now but have not checked the return line. I have not checked the pressure down stream of the filter going into the pump.

It runs real rough so I don't believe it is only one dead injector. I'm open to any ideas now!

You can find out for sure with a 14mm wrench in less then 10 minutes.

I hear you Greg last time I tried that diesel everywhere what's the trick a rag so you can't see the fitting?

[QUOTE=dieselbenz1;3329322................I see no air bubbles in the supply line now but have not checked the return line. I have not checked the pressure down stream of the injector. I'm open to any ideas now![/QUOTE]

This is what you need, a 2" length of clear nylon tubing reinforced with nickel plated brass. I have one spliced into the cigar hose (return to tank) permanently in my 85 300D. Does your engine have a cigar hose?

I should make a bunch of these and sell them. Every diesel engine should have one.

http://i31.photobucket.com/albums/c3...515_171528.jpg

So I started the car ran ok for 30 seconds then smoking and real rough idle. Tried to identify which cylinder it was with a 14 mm wrench. C1 and C2 when hard lines loose individually of course noticeable difference in idle. 3, 4 & 5 no difference seems to move around and tons of smoke again. Clear lines to IP no air.

Bosch Injectors were all pop tested from 1960 to 1990 with good chatter and pattern. I had thought at one time it was the monarchs.

Shot exhaust manifold temperatures 1 52 degs ., 2 51. 3 52, 4 49 & 5 44
Shot temps do injector lower bodies 1 32, 2 32, 3 32, 4 43, 5 44

Kinda points to #5 but by the amount of smoke sure sems to be more than one cylinder?

Why the nice idle once warm and no smoke, why the good start and no smoke.....

I made a very similar device but I included a tee with a pressure gauge and down stream of everything else I put an in line needle valve so I could vary the pressure. I know the pressure gauge should be in the supply to the ip but with a new filter there is no pressure drop. With needle valve fully open I was getting 6 psi of course fluctuating to zero. I pinched back until I was getting between 15 and 20 lbs. No difference it shakes and smokes until around 1500 rpm then runs smooth with a small amount of smoke. White heavy diesel smell.

So fuel system now ruled out maybe time for a compression test but I'll have to order that so that will take a week plus. Any ideas a plus.

Greg no the 602 Turdo does not have the cigar hose. How I miss my old 123 never had to get into that engine lots to be said for keeping everything cast iron.

Maybe I'll poke around the ip don't think it's alt related or idle controller related but there is another little box on the side which I have no idea what it does I recall seeing a vacuum line and maybe an elelectrical connection. Ideas are welcome.

Did we rule out bad glow plugs yet?

It is unclear to me from reading your posts where you were looking for bubbles. The cigar hose was just a location (i.e. return to tank) to let you know where the clear hose should go. If you did not have a clear hose returning to tank, you cannot say for certain "air or fuel system ruled out".

Glow plugs all new bench tested and verified working. I have now clear hoses on the supply to the filter, filter to IP and return to tank no air bubbles. While I wait for the adapter for the compression test the only other thing I can think of is to manually keep the glow plugs powered to see if it runs OK or not. It runs perfectly OK on a straight purge, above 60 degs C. and for the first 30 seconds. For certain incomplete combustion.

Well I got lucky in finding a compression terror with the glow plug adapter not my first choice but I really didn't want to wait for delivery from a mail order. This is not the cheap design either. Got set up for performing the hot test first since the intake needs to be removed. Engine started kept the revs around 2500 very little smoke as before reached operating tem then work fast to get at the glow plugs. Zero reading checked gauge ok reseated adapter still zero fired up compressor to check nozzle adapter air valve failure. The store is now closed and they rushed in the adapter for me so now just fighting with equipment.

Pulled an injector to retest it steady stream at 1500 psi, kept pumping spray pattern returned and chattering began but popped open at 1800 psi. I had spent an entire day setting these up and tested numerous times each injector all set around 1980 psi. I did have to add shims but I am confused at the drop in opening pressures now. Just wondering how many times to pump up the pop tester before one has confidence in opening pressures I had tried 30 times to make sure they are repeatable but now questioning if testing should be around 100 or so. I had cleaned everything in an ultrasonic bath, before reassembly cleaned with brake cleaner then blown out with filtered 30 pound air so I'm fairly certain assembly and final checks were done correctly.

With any luck I'll have a cold compression test completed later today if the shop can repair the adapter I tried but can't seem to remove the adapter check valve as I may mave over tightened it trying to get a good seal.

Ok finally obtained another non functional adapter for the compression tester but put in a tire valve and have cold readings now. Since this is thought the glow plugs I'm not in the mood to replace the intake manifold warm up the engine then strip it all down again. I'm hoping to take semi warm readings after plugging in the block heater for 5 hours. Any ways below are my readings but I have no idea if they are any good.

-1 340, -2 340, -3 290, -4 320, -5 270

I also spent some time while waiting for the adapter to recalibrate the pressure gauge I had used to setup my injectors and found a dead spot around 2000 psi so once I find a better gauge I'll repopulate all of the injectors to verify the condition.