We have a Cat 320d, 320DJDHE00173, smokes white at idle, clears up a bit when when rpms increased. Finning found #1 injector 7 psi lower than the rest,changed injector, no change , isolated #1 injector smoke cleared up a little, , finning says it’s a bad cyl,either valves or rings, we did a compression test on #1 cyl found to be 320 psi, can,t find any specs on compression pressure,seems low to me, is it true that these 6.4 acert engines have non replaceable cyl liners, your thoughts please thanks
I don't know about the liner issue but I haven't seen where Cat ever used a compression test for diagnosing and engine. They like the leak down test.
I would ask of coolant consumption, then oil consumption, if neither then is definite fuel smoke where lowering compression could be to blame. Starting characteristics? Hard, cold natured. must use glow plugs?
I guess one idea would be to run the compression test on all cylinders. Cat may not publish spec's but if you do find a substantial variation that would help determine the problem. A leak down test might be better as you may be able to determine where the leak is, say if you can hear air in crankcase, intake or exhaust.
That’s the first thing I asked, compare cylinders, the cat man was in a hurry maintains its the cylinder, and or the head, the head has no serviceable parts in it. Has a intake heater, starts nice, no coolant consumption, doesn’t,t use oil,going to change fuel filters & blow out back fuel Line to tank, change oil & air filter, simple things then go from there
Limit is 384 psi
Just thinking off the top of my head but how about swapping injectors to see if the smoke problem does follow or stay in the #1 cylinder. It won't cure the problem but prove if it is injector or cylinder related. Have you checked valve settings? If #1 is off compared to others that might indicate a valve problem. Also I might be checking valve lift, if a cam lobe is worn it could, I think, cause a compression problem leading to smoke.
Part number for liner is 5I-7523 it is not a wet liner and would require complete engine tear down and a trip to machine shop to bore old liner out and install and bore n hone new liner to size .. if its fuel issue feom low compression it should be showwing up in oil samples. I would check valve lash on cylinder 1 and have a leak down test done on that cylinder to find out whats going on as previously stated by others
Did a little testing today, did compression test on rest of the cylinders, found #1 cyl 90 psi lower than the rest , installed new injector in #1, didn’t,t change anything, isolated #1 cyl smoke cleared up substantially, so it’s #1 cyl for sure. New problem after working machine loading the hydraulics 3/4 throttle after 5 minutes it shuts down,takes about a 1/2 hr before it will start again . This machine came from Alberta, where the machines are idled a lot . The machine is real tight,suspect the 6000 hrs on the machine most of the them are idle, you can smell the unburnt carbon, off with its head, valves are little loose, nothing sticks out.
Went back in to sis right quick. Valves , guides and valve seats are all availble , somebody fed you a line of bs
This is what i would do if you dont see anything with valves or seats , pull number one seeing if you take head off cover crank do a quick hone. Clean ring grooves out and install new set of rings, but maybe have the bore measured first
Check the piston heights. These Mitsubishi derived engines will bend connecting rods if abused with ether.
Does it really get cold enough in Alberta to need that stuff? Thought that was a tropical paradise! Bent rod equals lower compression and white smoke. I would be careful running it if that is the case, only run long enough to get to place to work on it and then only at low speeds. I could tell you about a 12V-71 from many years ago that was not cranking over and I was sent out to check on it. But when I got there they had managed to get it to start. Sounded good but a little white smoke on left bank and when I call my boss he said hang around for a couple hours to see how it runs. They put the genset to work and I relaxed with cup of coffee in my truck. Never finished the coffee! Guy came over and asked why I shut it down. We went to look at the genset and there was massive amount of dirty Detroit oil all over the place and a hole the size of a basket ball in the block with a rod sticking out!
Update, did some more checking, blew out the fuel lines, Cat tech hooked up computer,isolated each injector, #1 cyl is creating a lot of smoke,but the rest are smoking now, when #1 is cut out, the white smoke continues, its getting worse, hard starting, have to give it fuel to start, the engine is getting over fueled .its of the opinion of many cat techs that it is fuel contamination . Sent fuel samples to Cat for testing
For the sake of not letting things spiral out of control, let's remove fuel from the equation. Get yourself a clean vessel of fuel. Run off that. Run return fuel into a clean bucket. So you can check for contaminants. Once you have a couple pints of return fuel collected, put your return back to your clean fuel. How does it run, now carefully check for air intrusion. Do any hoses have bad cracking/dry rot? Any swivel ends collecting dirt and stink like fuel? Got a water separator? What's the bowl look like? Do you have a hand primer on your transfer pump? Is it leaking? Is it locked down? Just a few to check before spending mad money
Agree with funwithfuel, a temp supply of known clean fuel and hook it as direct to the pump as possible to eliminate as many possible causes of leaks and contamination getting into the system.
Update, We did what fwf, Ksh suggested , didn’t change anything, smoking all the time, hard starting bluish white exhaust, 4 Cat tech,s can’t figure it out. Wouldn’t,it vibrate if rod was bent ? This is one for the books for sure. Can’t find much on acert 6.4 on the web. It sure makes you humble, looks like a $30,000 bill ahead of us. Thanks again for all the help much appreciated
Acert with common rail? That's a whole other ball of wax. New strategy in morning.
Perfect
Ok. You stated earlier that you had originally had issue with cylinder #1, and replaced that injector as well, correct? Did you inspect the cup that the injector sits in or the removed injector? With common rail any disturbance of fuel supply to one is problem for all. That said, if you don't have a perfect seat at tip of injector to cup, combustion gas can creep up forcing past tapered seat and aerate your fuel galley through a damaged injector or o-ring. What I do for testing is kinda redneck, but hey, it works. Take an old injector line, cut it in half. Either slide the nuts off the line and plug with ball bearing or in a pinch, weld the end of the line shut where you cut it. Remove 1 injector line, cap off rail end and injector with your new hillbilly block off caps. ###***Note, super important ***### If you've welded the ends, place some rags or an old pair of leather gloves on the ends to protect from pinhole streamers of fuel. This can't be stressed enough, the fuel is under high pressure and should be respected for the risk it presents. Try to start you engine. How does it run, yes a dead miss on one hole, but you are looking for performance as far as throttle response, reduced smoke etc. If possible, I would have the fuel return off the head running to a bucket through clear hose if at all possible. This will tell you if you have aeration occurring as well. Is return coming out in small dribbles or forcefully jetting out as foam. Obviously foam indicates combustion or compression gases getting into fuel galley. Then you will repeat the procedure for each hole. Do you have the means to see or measure the fuel pressures, both low side and high? This might be where a cat tech or at least his software would come in handy. Best of luck and please be extremely careful with the information and suggestions. High pressure fuel poses an injection hazard. You cannot get to the hospital fast enough should that happen. Common sense and healthy respect of what you are doing, you'll do fine. BTW what does your fuel/water separator look like? Any water present?
Oh gawd, DONT DO THAT.
fuel / water separator looks nice and clean no air. What you said makes perfect sense.When priming with hand pump , I could hear air in the system around the head and the first secondary filter ( there,s 2) was getting air from somewhere, tech said the noise was the relief valve,seemed not right to me, but he was the expert, but bothered both of us.Is it possible that when priming the fuel system you could fill the culprit cyl full of fuel and or if valves are not seating you could get air into the system.The Mechanic that did the compression tests lost the copper washer on #1, went and got another one,probably not the correct one, that explains everything. Will get the correct 1, hopefully it hasn’t, damaged the injector tube.The head will have to come off .Hopefully it’s just valves not seating.Will keep you up dated, again thank you for all your help. Ken & Greg
Found smoking problems, #4 injector had a damaged o ring, just light smoke, now to pull head to see what’s going on with #1 low compression. Will keep you updated
Wouldn't you want to reseal number 4 and see how it behaves. If it behaves good and run smooth why mess with it
And have you run your valves yet ? You've had the valve cover off checking injectors but have you run your valves?
We resealed the injector, runs with a slight miss
Fining tech said valves were a little loose, nothing that affects the low compression, took his word. Says the head has to come off, your thoughts
Start your engine, let her warm up. Run hard a full throttle loading up with hydraulics. For example, hold bucket curled in while exercising arm in and out slowly. This keeps your pumps stroked up, keeps the engine loaded and avoids burning the oil cause you're cycling it through. Get your oil and coolant up to temp. Let her idle, pull the oil cap and see if you got excessive blow by. If you're not pushing blow by, not overheating or washing oil out with fuel, I honestly don't see a reason to go after it. Volvo runs low compression to start, we've had em so worn compression was in the 200's , still run like a top. I'd clean up and reseal all cups and injectors. I'd run the valves myself. And lastly, I'd be absolutely positive my low side and high side fuel pressure was hitting its mark . Not a big fan of unnecessary repairs, big fan of root cause. It's a slippery slope and easy to get tunnel vision.
I agree, will suggest to my friend, there’s no blow by , not heating up, no fuel dilution, will set the valves, it’s worth a shot