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Discussion Starter #1
I have been trying to getting my 4bt started over the last couple of days and as of now I am close but still not there yet. The motor is a '92, cpl 0986, w/ VE pump. It sat for about 2 years with no storage prep. I turned it with a bar on the flywheel and it had about an 1/8 of a turn range before it would stop, I suspect a little oxidation on the cylinder walls. I had the injectors out so I sprayed some PB into the cylinders along with a few drops of ATF. I also pre-oiled the rockers, valves, and just about everything that moved. After about 15-20 minutes of gently working it back and forth it started to smooth over the hang up and I was able to turn it over smoothly through full rotations. I then reinstalled the injectors with new seals and new hard lines on cylinders 3 and 4. I bled the system and tried to fire it up.... after cranking and bleeding for a long time (2 hours off and on, 2 days in a row) it started and sputtered and ran for about 3 seconds. it would start again if I gave it full throttle while cranking but would soon die even if I left the throttle wide open. I re-bled the lines and there was little more air in them. This went on for a while but nothing really changed. on my last attempt at bleeding, I loosened the small 10mm bolt in the banjo fitting on the output of the fuel filter (from the filter to the IP) and when I re-tightened it I stripped it. So now I know I have air in the system, I ordered a new banjo bolt, the captive bleed bolt, and sealing washers. Everything came yesterday so I going to go and try again today. I am going to replace the fuel filter while I'm at it, I have also pulled the stop solenoid plunger to eliminate that as a problem, but there are two things I am still wondering about:
1) I noticed that I am getting nothing out of the return line. Should the return be submerged in fuel to prevent air getting sucked in (not sure if that is possible)?
2)where would I install a fuel pressure gauge to make sure the lift pump is operating? (the hand lever does move fuel to the IP, does that mean the lift pump is still good?)

BTW the engine is on a stand, fresh fuel that is being gravity fed to the lift pump. Thanks for any words of wisdom on this stuff!
-Bahndo
 

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Discussion Starter #2
Well after another day of working on this I feel like I am getting closer. It did not run today but I think I may have a stuck injector. After changing the banjo bolt and sealing washers I bled the lines to the IP and then cranked it and bled the injector lines. When I had all four lines cracked fuel would spurt from #1, #2, and #4, while #3 would bubble and spurt a foamy mix. With the engine cranking I tightened down #4 and it immediately began to fire on that cylinder. The same with #2, and then #1, and it was almost running on it's own. I tighten #3 and after a few cranks none of the cylinders would fire.
My thinking is that air is being pushed into the system from the #3 cylinder through a stuck injector. Does this seems like correct logic to anyone?
I repeated this a few times with the exact same results. Some thing else I noticed was after I went through this when I bled the lines from the fuel filter to the IP air hissed out as soon as I cracked the line. Again I am not sure on any of this but looking for some advice. I still do not have any fuel flowing from the return line and I am not sure if air could be sucked in somehow from there. A mechanic buddy recommended teeing the return into the supply line and having the lift pump pull the fuel through, any ideas on if this is a good idea, bad idea, or correct configuration?
Thanks for any advice on the topic.
-Bahndo
 

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bleeding

You should be able to turn the engine over with a wrench with a high pressure line loose. While operation the hand priming lever the fuel will flow continuous when that cylinder is line up. A solid flow of fel will come out if the air is purged from the injection pump. Be sure there is 12 volts to the shutoff solenoid. I had one with intermittent no start and low power that needed a shutoff solenoid. Also check for return restrictions. Return restriction can cause a short run and shut of condition in roosa master pumps but the bosch VP just pushes out the front seal and fills the engine with fuel.
 

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It's easy enough to have your injectors pop tested and disassemble them and clean them.

This may not help, but a 4BT in decent shape will start and run rough on 2 cylinders, it'll have a healthy miss on 3, but will run and drive.

A stuck injector isn't going to push air back into the pump. The IP return line doesn't matter where it goes as long as it isn't in the pump feed. You'll just recirculate air that way.

If I were in your shoes I'd be tempted to pull the top off the IP and check the insides for rust. If the lever arm inside the pump is rusted bad enough it won't move, pulling on the throttle won't break it free. Your description of giving it full throttle to get a sputter then letting off and having it die might support that. That and with the pump top off you can easily fill the pump full of fuel.
 

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I agree with 250 on the IP, especially if no fuel on return line. You'd be surprised what the plastic end of a screwdriver can break loose.:)
 

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Discussion Starter #6
average250-
Thanks for the input. I am going to check it out again today, I am a little nervous to pull the top off of the pump just because I have never done it and really don't want to screw it up, is there anything to watch out for when doing this or is it pretty straight forward?
Also it still seems like I should at least be getting some fuel out of the return line, any thoughts on why nothing?
Thanks,
-Bahndo
 

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Discussion Starter #7
Well today turned out to be another very informative day for me. I changed the fuel filter and bled the lines and low and behold it fire up. It ran rough for 15 sec. or so and then died. I checked to the lines again and their was still air in them. I went through this a few more times and kept finding air when I bled the filter to IP line. I was wondering if it was possible for the lift pump t be leaking so I decided to pull and check. In the process I found that one of the sealing washers on the banjo fitting at the filter was not much more then a thin steel ring that had been cranked down on so hard it was wafer thin. This was def. where air was leaking in bounce . I called up CV diesel in Greencastle, PA and they had them in stock. I figured I would have my injectors pop tested and rebuilt if needed while I was there. Bad news came when the service guy asked me where the hell the injectors had been and why there were metal shaving in them. I told him about my motor and that it had been sitting and apparently had been sucking in air for who know how long. He seemed to think that the IP maybe supplying the metal. YIKES! I can't quite swing an IP rebuild right now so I may have to see if I can troubleshoot it a little and see if it for sure the IP. Any advice on this?
BTW- 3 of the injectors had pluged holes and all were poping about 60 bar below the specified 245. Not sure what the next step is at this point....
-Bahndo
 

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It's your call based on your abilities, but the VE pump manual is free to download on the web. You can completely disassemble, check and reassemble the IP yourself on a clean bench with basic tools. The pumps are very simple inside. If you find a bad component a Bosch distributor can order it for you.
 

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I would highly recommend you get the VE rebuild DVD thats out there. It is very good for the $50 or so bucks. Unless you have really been into the VE pumped diesel for awhile I don't think you would be dissappointed.

On a side note, there are a ton of people out there who have had success just tearing into these pumps willy nilly. But there really is a method to the madness IMO. If the thing comes apart and the parts are cleaned and placed in a manor so that they can be reassembled in the exact location and orientation that they came out in, performance should not be affected.

In your case it may not matter. You could buy the reseal kit, take it apart and reseal it, cleaning etc. looking for obvious breakage etc. Put it back together and if it works, great. If not your only out the $20 and you get the experience. It could get you by until you could afford a rebuilt one, exchange yours of course.
 

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Discussion Starter #10
I have to say that my "fear" of tearing into this thing comes solely from hearing others say "what ever you do don't open up the injection pump". I have made it this far in my life taking things apart and putting them back together so what the hell, I have the manual downloaded already, now I just need to order a seal kit and pull the pump off the motor. I am sure I will be posting as I go so if you have done this before please keep an eye on this thread for more upcoming questions. Thanks for the inspiration,
-Bahndo
 

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IP repairs

I'm like he was I've been told to never tare into an Injection pump now you boys are saying tear it up Cowboy ...My pump on my 4bt is leaking drip drip drip off the back of the IP ...So I guess I should be able to repair this also with out sending it for a rebuilt ...Man that would be a good lick to not spend 750 and keep Momma off my ass...
...So down load the manual and buy a seal kit use only what I need ..correct..
 

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If you can take something apart, figure out how it works and get it back together the VE is a simple task. Common sense is a requirement, just like anything else with some mechanical complexity. There are a couple things that could trip you up if you just ripped all the parts out, dumped them in a bucket without paying attention and tried to get it together.

Before tearing it completely down measure the installed depths of the full load screw and the governor support bolt with calipers. Put these back at the same depth and you'll be fine. The throttle shaft has a small index mark on the end of it. Scribe deep marks into the throttle arm that line up with this mark so you get the shaft indexed right. Pay attention to the orientation of the piston and the cam, or easier yet, the piston and the keyway on the input shaft, it will go together two ways. Get that stuff down and you'll have to try hard at screwing it up.
 

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If it is the hydraulic head o-ring that is easy to reseal but I recommend removing the IP rather than trying it on the engine. I did mine not all that long ago, I installed all but two of the seals in the IP, I didn't want to have to gut the pump where I was doing the work that night, it was only a couple months before the gov' shaft seal sprung a leak... Of course that was one of the two seals I didn't change out! PITA.

The hydraulic head seal can be changed without completely removing the hydraulic head. But you have to be very careful not to loosen the bolts too much and have the jack-in-box effect. Also there is a viton hyd. head o-ring available on ebay, he also has a viton front shaft seal now I see. These seal materials are superior to what is available elswhere. This guy has the hyd. head seal procedure as well. It is a very well known How-To among VW owners. I'll post a link to the seller etc.

This link is the more expensive Viton kit, DGK 126R. He has the regular DGK126 kit also. Or you can get the kit at any authorized Bosch shop. The 6 cyl. kits were $16 the last one I bought at my local shop.

http://cgi.ebay.com/ebaymotors/VW-Diesel-Injection-Pump-Gasket-Kit-Rabbit-VITON-BIO_W0QQitemZ170289131422QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item170289131422&_trksid=p3911.c0.m14&_trkparms=72:64|66:2|65:12|39:1|240:1318

Another hyd. head o-ring seal replacement view.

http://www.dieselvw.com/images/PumpRearSeal.JPG

I have this DVD set and it was $50.00 when I bought it. You can't go wrong in my opinion...

http://cgi.ebay.com/ebaymotors/Diesel-Injection-Pump-Rebuild-DVD-Book-Kit_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1205Q7c66Q3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a1Q7c293Q3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZitem220340677308QQitemZ220340677308QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
 

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Discussion Starter #14
Sweet, the DVD and seal kit are on the way. If anyone is thinking of running bio-d then I would highly recommend getting all the viton seals possible as it is a bio compatible material.
-Bahndo
 

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I was told that by an actual Bosch tech rep, not a dealer. Not saying it's gospel, but my impression was he knew his stuff pretty well. Supposedly 1998 was the transition between the old nitrile/buna to viton parts. Parts made after then should be good to go for bio/ULSD.
 

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I do recall reading something along those lines on one of these diesel forums.

I will add this, I wouldn't pay what some of these clowns are getting for a seal kit. Greasecar etc. The kits should not be much more than $25.00.
 

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Discussion Starter #19
Not sure if my seal kit will say what material the seals are but I did order the $20 kit, if I can figure it out I'll post it up.
-Bahndo
 

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update...not looking too good

I got my seal kit in the mail a few days ago along with the rebuild dvd, which I highly recommend to anybody that thinks they might want to try to go through their own pump. Keep in mind that the pump in the dvd is a VW version so there are a few things that differ but it is mostly tools required stuff.
I pulled the pump and clean it up a little a few yesterday and prepped to tear into it today. Things were going very smoothly in the beginning, I put the laser cutter to use and made two specialty sockets to fit the round corner triangular head bolts. Once I had the cover off I could see that the governor lever assembly has a fair bit of corrosion on it and it was def. sticking a little. At this point everything seemed fine and I did not see and signs of damage. My first sign of trouble can when I tried to remove the timing piston/cold start advance, I was locked in it;s bore. I had to drive it out with a drift and when it finally came out it showed some nice gouges from where the housing had corroded around it. When the cam plate come out I found a major problem. First the spring that is supposed to be in there was no where to be seen. Not sure if some pumps don't have them for some reason but it was def. not there, I was looking for it when I pulled the cam plate. Next was some very obvious galling on both the cam plate and the actual rollers that the plate rides on. I am not but I think maybe some of the parts had seized after sitting and then when I started turning it over it chewed up the spring and damaged the cam surfaces at the same time. At this point I was pretty bummed but was still thinking the parts are replaceable so I kept digging. The last part to come out was the feed pump housing (I think, the plate the the vane move eccentrically in) and it is a mess. Major corrosion, and to top it off the pump housing has some questionable markings in the bore it self. I am interested to hear if anyone thinks this pump is salvageable, I have already prepared myself (mentally at least) for the idea of sourcing a new pump. Here are some pictures of the damaged parts.
Roller bushings:




Cam plate:


 
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