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I'm having a spot of bother with my oliver bd.  The smoking problems its had since worked on the engine is getting worse not better, so I took the injectors out and had them serviced. 4 out of 6 were very bad and the other 2 weren't correct ( thats another story though (locally rebuilt injectors!)).  The injectors are now done, it runs a lot better but still has a bit too much smoke.  Cracking injection lines off one at a time I found that number 3 injector had no effect on the engine running but did reduve the smoke, I also noticed what lookes like less pressure than the others when you loosen the pipes.  This does not add up for one fact, if the pump is down on pressure on the third outlet i assume it should not open the injector, so why the smoke?. Incidentaly I have moved the third injector to the sixth to check it isn't a bad injector still, but the battery are flatt after all my tinkering and no running so I wont know what that does till later. Any comment appreciated.

Sam: First of all good move on move the injector. What color smoke are you getting? Another thing to do is to take the exhaust manifold off and see which cylinders smoke the most. Have you rechecked your valve clearances. What do you have the pump timed at and have you checked it lately? I do not know about your fuel but I had a little experience in some third world countries where the timing need to be changed to match the fuel availabe in that country. Some of that third world fuel makes a ton of smoke

John.  I have now tried it with the injector moved and the problem stays with the cylinder.  I don't think its timing although it could be that the timing is out inside the pump if just a couple of the cams or folowing rollers have worn down.  I can clear the smoke to very acceptable levels by slackening 1 and 3 injector pipesthis causes no decrease in engine speed / note.  I'm trying to find someone around here with a compression tester as this would help imensly. The problem deffinitly lies with those two cylinders and not the setup of the whole engine. Sam

Sam: there are a couple of ways to do this. You can do this with all 6 injectors or one bad one and one good one. Your BD has a "pintle type" tip so it makes this a litle easier to do. Take a known good injector and your questionable injector(s) out of the engine and attach them to the fuel line so you can see the spray pattern. You will need to turn the lines around. Compare the good and the bad. This will tell you real quick if your nozzle is opening and atmozing the fuel like it should. Questions send me a PM. The boy told me last wek he has some spring flowers almost ready to bloom. John

I've had the engine compression tested and the pump tested now and there both OK.  So I've got compression and fuel being atomised.  But it still isn't running on 3 and 1.  The only thing I can think of is camshaft wear or tappets (although I have already set the tappets before). But if i've got compression what could it be in the valve train to cause this, what I mean by this is what is it doing wrong. any help much appreciated. Sam

I  chased a rough running engine problem, a couple of years ago, that had me baffled also. Tried everything I could think of.  Did everything that was suggested by the experts.  Replaced a lot of parts.  Parts that really didn't need  to be replaced.
  Still had the problem.
What it ended up being the real culprit was a leaky manifold gasket.
Two of my cylinders were always sucking in too much air.
When you mentioned you were going to adjust the tappets and check the cam, etc.  made me flash back to when I did the same thing.
Maybe spray some starting fluid around the intake ports,right at the manifold, while its running might help tell if thats  the trouble. Or just replace the gasket if its not too expensive.

Does it smoke when under load? My BDH smokes alot when cold and sounds like it is missing, after it is warmed up it is better, but it still sounds the best when loaded. My engine was compltely rebuilt, injectors rebuilt, but the pump was not.
Randy

Sam, as RLH asked, does it smooth out under load and quit smoking blue? Does it then go to nice black smoke while it's pulling?

My OC-12 does this. Sounds like it's missing or stumbling around at idle. Blows blue or white smoke rings too. But smooths right out and runs perfectly under load.

This is common and pretty much normal with these engines. A muffler will help smooth them out. It is worse with the Roosa Master pump too. This is from my Gramps who was Experimental Engineer there.

Blake

Quote from: "Jim N"I  chased a rough running engine problem, a couple of years ago, that had me baffled also. Tried everything I could think of.  Did everything that was suggested by the experts.  Replaced a lot of parts.  Parts that really didn't need  to be replaced.
  Still had the problem.
What it ended up being the real culprit was a leaky manifold gasket.
Two of my cylinders were always sucking in too much air.
When you mentioned you were going to adjust the tappets and check the cam, etc.  made me flash back to when I did the same thing.
Maybe spray some starting fluid around the intake ports,right at the manifold, while its running might help tell if thats  the trouble. Or just replace the gasket if its not too expensive.

Jim, this is very true with a gas engine, but would have no bearing on a diesel as they don't have any vacuum. Now if it had a turbo, a manifold leak would be very detrimental as you would loose boost. Nevertheless, a leaking manifold is no good as dirt can get into the engine.

Blake

I'm testing the engine with the throttle open about half way, and its very clear that the two cylinders aren't firing at all.  It does sound better under load but its that noisy it would be hard to notice suble misses! I re-iterate that if I slaken the injection line the smoke is significantly reduced to a reasonable level.  So I'm certain it is actually not running on those cylinders.  I can only wonder weather its the oposite to Jims suggestion and thats its been starved of air on those cylinders, so can't burn the fuel. I've been driving a county crawler tractor today as mine's out of commision, which I really enjoyed but could have used diff steering as we were loosing grip when we corrected the steering. For any of you who haven't heard of a county, its a conversion of a Fordson power major tractor and is roughly model B size but a bit lighter construction.  Thanks for all your help and keep the suggestion comming no mater how unlikely they may seem, I'm sure your all aware how frustrating these sorts of problems are. Sam

Sam: What color is this smoke? Also have you turned one of the injection  lines around and cranked it over to see what kind of spray pattern you have on the injectors that are giving you problems. You said you checked compression. What was it on those two cylinders and then what was it on the other 4? Awaiting your answers. John

John, the smoke is white mostly.  I haven't recently tourned the injectors around (I did before I had them repaired) but I have moved them about and had the pump tested, but I will tourn them around when I get the pump back as this would help eliminate them as I suppose it could be a small crack in a high pressure line or something.  The compression wasn't very high on all of them, but we didn't have the correct fitting for the tester so they were not going right in as far as the injector would and also the battery was getting tired so we had a fairly low cranking speed, but they all showed around 275psi, even the ones that aren't firing. Sam

Sam; If you had 275  and now it misses the first thing I would do is take the valve cover off and check valve clearance. It could be one of the 2 tightened up on you. Also getting back to the intake thing, You do not have vacuum, but I have seen a couple of engines where the intake manifold gasket did not seal and dirt got in the cylinder and ruined it. They passed around a ring set one time at Oliver service school out of Hercules not that it made any difference that failed in 10 hours. Reason there was a small hole in the aircleaner and that hole left dirt in.

I checked the valves last night and nothing was very badly out a couple were aprox 20thou out.  supprised if that was the problem. Sam

While you are checking valve clearances, you might want to also check valve timing.  Last year, I was working on another rough running tractor that had a very hard to find problem.  While I was checking the clearances , I noticed that when number one piston was at TDC, the intake valve was not completely closed. I had to rotate the flywheel a bit farther  past the timing mark to get the valve totally closed.   I then came to find out after much more removing of parts, that the key in the camshaft gear had sheared off and the gear rotated another 20 to 30 degrees on the shaft before it jammed it self there.  I couldn't believe the tractor would run at all.
 The owner said it had started to run rough but was able to finish mowing another  5 acres of grass before we drove it up on the trailer.

Sam: Any chance you can recheck the compression? Also have you checked to see what kind of spray pattern you get on those two cylinders?

I've had her running again tonight having tried some of the suggestions and it is running better but still not on the third cylinder, had an interesting suggestion from a very experience agricultural mechanic who himself collect old tractors.  As soon as I said it was indirect injection he asked about the swirl chambers, apparently if there loose or cracked or defective in any way then the engine will run very poorly on that cylinder.  Got to be worth investigation, anyone heard this before.  Sam

Sam, I have seen two different injector cups, one piece and two piece. The top of the two piece has a little nub or bump on one side that fits in a notch in the block to keep it from turning. If it did turn somehow it would cause a problem. When I had my engine apart it had some of the cups that had part of them burned away. Have you had the head off?
Randy

Yes, I had the head of quite some time ago and can't remmember what the chambers were like, other than that the first time I put the head on after I had it skimmed I had to file the top of the chambers to stop the head sitting on them.  From what I can remmember the were easily removed without any tools just with my fingers.  I'm going to take it to the ploughing match this sunday as it is, then take the head of afterwards to look at them.  Thanks Randy