Wondering if there were any Detroit diesel mechanics out there that would let me ask some questions about problems that I am having with a 8V92 Industrial . Thanks
I've spent a lot more time with 53s and 71s than 92s, but ask away. I'm sure I or someone else can help.
I have a 8V92 on a well drill rig (deck motor). Came in down on power, had 3 bad injectors and a stopped up inner cooler. No tags or numbers stamped anywhere on the block. Suppose to be a 500 hp unit. It has 9290 injectors and all the info I find says the injector sets at 1.484; But they run out of stroke at this setting. They were set at 1.60 when it arrived. It will crank and run at this setting, but the performance is not right. Any ideas on the correct setting? I have done a lot of in line DD work, running everything the same way. Thanks for the help.
Not sure what you mean when you say "they run out of stroke"? Also what was stopped up on the inter core? Assume this was either replaced or cleaned out. I did post your question over at https://groups.yahoo.com/neo/groups/DetroitDiesel/info to see if anyone there might have some thoughts.
Was the original setting 1.460? I don't know much about the industrial 92s, but most industrial V-71s run a 1.460 setting with standard cam timing and 1.484 makes them run like a dog.
That makes sense as the higher the injector is set the more retarded the injection is going to be on the engine. Still don't understand what is meant by "out of stroke". Might just be a terminology difference.
The 1.484 is for advanced timed engines; usually turbos. It goes with having the idler gear advanced one tooth. The higher the injector is set, the sooner the rocker arm will depress it. I am pretty sure there is a model and serial number on the block. Look for a flat machined spot; maybe above the oil cooler or on the top of the block behind the blower near the front of the flywheel housing. A couple of things to check. Put a small screw driver in the rocker and injector arms and wiggle to check the bushing wear. If there is any play, they are shot. Make sure the valves are set right. Another more advanced check is to pull an air box cover then rotate the engine until the rings are visible. You should notice an indented line in the compression rings. If not, they are worn out. I don't really recommend this check because the air box gaskets can be stubborn to clean up and they are in nasty places too. As always, clean fuel filters, make sure the engine is getting fuel and no plugged intake lines, and make sure it is getting all the air it needs, so clean air filters and few bends in the intake piping. Good luck.
I was doing some research on this also and found tons of variables on injector timing for the 8v92 I'm guessing the tags on the rocker covers must be long gone also , I'm not sure that a stamped model and serial number would give the op all the neccessary info but if it has stamped info in it then he is definatly going to have to contact MTU to help decipher it
This should help. I hope I got the right page; if not I will reload.
Serial number stamped on the block should be on the right hand rear side just under the last air box cover. Should look like this: xxxx-xxxx 8vxxxxx Lower number is the engine serial, the upper 8 are the arrangement number. At least on a V 71. I think the 92s are in the same spot. Oops, too slow.
When I downloaded the 92 info I got the same for 53,71,149, & 60 series too. If anyone needs any, give me a shout.
True in part but the higher it is set the more the plunger in the injector has to move to get to the point that the upper and lower ports in the injector bushing are both cover to start the injection. I know in the V71 manual there is an explanation of how to determine if the timing is advanced or standard. In the V71 book it is shown in Section 1.7.1 and I would expect to find it in the same for the 92 series. It is the section of the manual that deals with the gear train. It involves finding top center on one cylinder then using this to compare the injector travel to a set of standards given in the book. Not positive on the 92 series engines but on the V71 engines the Model and Serial numbers are stamped in the block between the air box covers below the head. Edit I see formerwrench got the page out of a 92 manual so that should work better!
Usually the turbos and big injector engines were A-timed. I have done a lot of them and one time I spent about 5 weeks at the Freightliner factory changing an order of 12V71 from standard to A timed. A big winery bought 60-70 new trucks and there were not enough A timed engines available so we had to play catch up and change them before they went to assembly. It is a straight forward process. The cams are keyed so when they line up with each other the mark for the idler gear is in the right place. The holes in the crank gear are offset so it goes together one way. The idler has 3 marks; one for the crank, and the STD and A for the cams. There is an offset for the idler hub to set in and a little fitting for oil to the bearing so the idler is limited to where it lines up. With the cams aligned, the idler close but not installed, the crank can be barred for the marks to all line up. There was a standing rule to have someone else take a look and verify the marks were aligned. Then the rear of the engine got buttoned up.
First off, there are no numbers on the block. It was factory remained at one point. The tag was riveted to the block, still have rivets do not have tag. The company found some old paper work from DD that said the serial # 8FF5093 model # 8083 7400. The turbo had been replaced do to seal failure and made a mess of air flow through the cooler. I replaced the cooler, I have checked the piston rings and they looked good. ( Around 1,000 hours on a rebuild, then set for 2 years prior to coming to my shop for lack of power. Earlier I said the injectors ran out of stroke, I would like to clarify this statement). Valves down, injector up, set the injector to 1.484, rotate motor, when that injector is depressed, the motor will not turn through (bottoming out injector). Go to 1.600, the motor cranks and runs, ton of black smoke and does not want to achieve top rpm. I pulled the injectors today, 3 would not spray properly. This still does not explain not being able to set the timing according the book. Thanks for the help.
1.600? Does this thing have DDEC electronic injectors???
No it has mechanical 9290's.
Ok, Just asking. That !.60 just seem odd. I did some 92 tune ups years back and they were in the 1.4xx range, my tune up kit only goes to 1.50 and I didn't need any odd gauges. Your engine must have some wild cams.
My 92 manual shows using the 1.600 timing tool with the 9290 injector . As for the black smoke check the emergency shutdown flap at the blower intake , clogged air filter , collapsed air intake duct ,& turbo failure ( with the engine off make sure the turbo spins free by hand ). Black smoke is a sign you aint gettin enough air .
I agree there must be something different about the cams. They were set at 1.600 when it got here, which is why I went back to it. Done a lot of 6-71 rebuilds and have never run into this before. Thanks for the help.
Air cleaner is unhooked, the turbo turns free. There is no shut down flap. Checked exhaust pipes and muffler for blockage. Could you tell me what the setting would be if I went back to the 9G85 injector? Thanks for the input.
I'm betting after those injectors were bottomed out they dribbled pretty badly. I had 1 dribbler in a 3406 cat that smoked the whole yard up at idle. good to see that you had the info to verify the injector setting. I sold my 92 manuals a few years back to somebody that had more use for them than I did. Still got the 71 books though. Them goofy Wabcos and Terexs are still out there.
I'll check in the morning . My manuals are at the shop & I'm planted on the couch this evening .
Sure could be the problem .
Aint that the truth RZucker ! And Grove truck cranes , HyHoe excavators , & GMC trucks with the two stroke noise makers . Along with the goofy people that use them . Now there is where the real problem is ........... :drinkup
After setting to 1.484 ,I barred to motor over by hand until I met resistance. May have damaged the injector, but I did not come against it hard. Backed off the injector a little and the motor turned through. Thanks for the input.
Thanks for checking your manual. I already bought one 800 page manual online that got me absolutely no where. I did not want to buy a service manual until I got the serial numbers, which I got today (to make sure the manual will cover it). Thanks for the help.
My manual don't show the 8 V 92 TA using the 9 G 85 injector . However the 9290 seems to be the common injector in that series . Let me take some time this evening & scan in the tune up spec charts that show all the combinations as I don't want to miss speak & steer ya wrong . My manual is a 1981 vintage .
I have seen the key sheared on the crank gear.
I have seen the fuel return line blocked that makes them do funny things although doesn't sound like it in this case.
Is the crank gear keyed on a 92? Seem to recall all the 53-71 series engines had the gear that drives the cams at the rear of the crank were held on with I believe 6 3/8 fin bolts with one offset to be sure it is installed correctly. Plus I don't see how even if the cam was out of time with the crank it would effect the travel on an injector. Don't know what the problem is but sounds like there is either a mistake in the way the injector is being adjusted, there is an error of some kind in the injectors themselves or the cam has too much lift on the injector lobe. Not sure if there is a spec. in the manual on the lift of the cam lobes for the valves or the injector. I don't see any such spec's listed in my old V71 book.
Ok , opened up my newer 92 manual ( 1988) and sure enough around the mid 1980's we start to see the 9G series injectors . Top scan is the blown up off the same page so we can see it better . Yellow lines are injector , horse power , & timing .
As far as plunger travel it may be the plunger travel on the OP's injectors Bottoms at a higher point than a standard Injector. The cams may be the standard lift.
TD25, Thanks for the help and taking the time to look these numbers up. I am glad you found the 9290's were speced out to the 1.600 range. However the 9G series injectors show 1.456. And unless the 9G injector has more travel I will never be able to set it to that specs.
Outside the service manual Ran in to a few oddities over the years where we went by the book and it still did not work correct . This happened to me back in 2011 when the 8 V 71 went down on the WABCO scraper . HeavyEquipmentForums We got the engine back together & set the valves & N-60 injectors at 1.460" like the book sais ..... Engine started fine but sounded like it had a half ass miss & did not have any power . Scratched my head for a bit ..... Then just started backing off the setting slightly then running the engine . Noticed it ran a little better each time and did this until we noticed diminishing returns . Much like twisting a distributer on a gas burner to find the sweet spot . The 8 V 71 ran best at 1.525 & that's where we left it & went back to hogging dirt . Book calls for 1.460 . I have no explanation as to why ? :beatsme Oh yeah , we made our own timing tools out of wire & depth mike . Just rest the wire on the machined surface of the injector ( not in the timing tool hole ) Some times you have to step outside the box
Look at post # 35
td25c, Yes I understand; The first thing I did when it would not turn through is start backing off of the adjustment in several steps until I ended up back at the original setting. That is when I pulled these (low hour) injectors out and pop tested them; I found 3 bad. I'll have the injectors back Friday or Monday and will give them another try. I cut my teeth back in SC working for a man who had over 300 pieces of equipment; TD 15's and 25's, Wabco's from 111 A's and up, even with a few double barrels. Even the water trucks were made out of cobbled together Wabco pans. Thanks for the help.
Sounds like you have been around the block as well running old iron ms0115 . I'm satisfied your 8 V 92 is suffering from a simple issue . Guy has to bang his head a bit before finding the cure . Hopefully a new set of rebuilt injectors will fix it . You may have to experiment like we did on the WABCO to find the " Sweet timing setting " .
Guess one question I would still have is did this engine run good after the original rebuild? I've seen times when something was assembled wrong and people just live with it not working right then years later you are asked to work on it and only after you beat your head against the wall on a problem to be told "Well it's been like this since Fred rebuilt it back in 2009!" Hope replacing the injectors does clear up this problem. Where were the spec's for the 9290 being set at the 1.600 show up, did not see that in this thread?
The 1.600 showed up through one of td25's post from a shop manual. About 4 years ago I sold my diesel business of 20 years in SC. Moved to TN for semi retirement and started a new shop that hopefully my son will take over soooon. Regarding the drill rig, I came into this situation very late. This well drilling outfit has been a very good customer and has kept us very busy. After building several CAT deck motors, 7.3, 6.0, 6.4 and 3208's for them, they dropped this rig off that I have never seen. Here is the story I got; Ran it for 6 years, it had plenty of power. Started loosing about 400 rpm under full load and this was not acceptable for this application. The only people in this area at that time that would work on the dd was an actual dealership. They sold them on a rebuild, the problem continued. They ran it for about 6 months, carried it to a private shop. He sold them on bigger injectors and a new turbo; The problem continued. Then they spoke to the drill rig manufacture and they sold them on needing a new air end;And the problem continued. They parked it, bought a new rig and 2 years later they bring it to me to fix. Test ran and it seemed to have a restriction in air flow. Pulled the turbo and there were no problems, practically new. Pulled the blower, no problems there. The blower mounting gasket was bent over and pinched in one spot, may have been losing boost at that point. The inner cooler was partially stopped up apparently from a leaking oil seal at the turbo (gummed up). Repaired all these items. Running valves and injectors to see where they were at and here we are. They spent an excess of $50,000 before it got to my shop. Needless to say this is not a typical straight forward problem.
There are not any Ken . This was my screw up guy's....... I glanced at the service manual one morning at the shop looking at all the timing settings and 1.460 stuck in my mind for some reason and that was not even correct for the 9290 . Then when I saw 1.600 mentioned it sounded rite & agreed with it . Mind must be going , should have just taken the time to scan in the page on the 9290 . Been pulling some long hot day's so you guys just have to pardon me . Did spot a Detroit 9F 90 that sets at 1.520 , that seems to be the tallest factory setting I see for the 92 series .
That's pretty close to where we set the N 60 injectors on the 8 V 71 in the WABCO at 1.525 . Still baffled over that mystery :beatsme. But she makes good power & hogs dirt & that's what counts .
TD25C Thanks for the correction. I hate that I did not catch it before I passed it on.
My bad Bro , just got a lot of irons in the fire now .
Timing specs for the early NA industrial V71s were standard cam timing and 1.460 for N60 and N65 brown tag injectors. Later engines ran advanced cams and 1.484, It was recommended at overhaul the early engines be converted to the later specs. Your C-pull may have been converted before you purchased it. It is odd that 1,525 makes it run good. Maybe somebody goofed and advanced the cams an extra tooth? I've always built them by the book so I really don't know much about building a hotrod. The 222F Wabco I had ran N65s at 1.484 just fine with plenty of power. I did build that engine from the ground up, so I know what was in there.
Okay, so now we know "The rest of the story" as Paul Harvey used to say. It had a problem, and it has NEVER run right since, to top it off a dozen people have screwed with it and Gawd knows what all is frooked up in the poor thing. I know it's not what anybody would want to do, but if it was me I would rip it down and start checking parts against a build list, something is off, wrong pistons, wrong cams, wrong injectors, timing, as somebody suggested timing gear on wrong or slipped somewhere, wrong rockers? I know it's all supposed to be the same but how do you know? Really needs to be on a dyno when you tune it so you can see what you're getting, but who's got one of those in his garden shed? Is this engine by chance running reverse rotation? Just curious.
Reman engine= no change Reman air end= no change. Wag: you have a bad air hose or a bad swivel .
If this information is correct (and personally I see no reason for it not to be) it could be the key. If the engine initially underwent a full rebuild which didn't cure the problem then wouldn't this point to something that wasn't replaced during that first rebuild..? Don't ask me what though, but whatever it is I'd suggest it won't be obvious at a quick glance.
I know I am a johnny come lattley to this thread but why was a rebuild ordered? where there any diagnostics run on this engine before rebuild? IE compression test? Boost pressure or in case of a Detroit air box pressure. fuel pressure? fuel flow? air restriction? to name a few. If none of this information was gathered than just throwing a rebuild at it was just a guess and not proper diagnostics. It is not to late to do these tests. You might find something like a restricted fuel hose or a leaking charge air cooler that can kill HP. Also if it is old mechanical engine with a rack it is realy important to have the rack set up right. when its right they scream when its wrong they are dogs. Its getting hard as heck to find anyone anymore that knows how to set one up and seems to be a lost art. Its all done by feel and takes a skilled hand to do it.
Hey something else you can do. loosen or remove the exshaust manifolds and run the engine. You said lots of black smoke. notice is the smoke coming from one port or are all the ports smoking the same. if it is one port there is a good chance the injector at that port has blown the tip off the injector. All it takes is one injector to do this and it will smoke to beat all and be a real dog. This is real common if you get water in the fuel as the injector has a hard time passing the water and ends up blowing the tip off the injector. if this is the case and you loosen the manifolds you will find it as one port will be bellowing black smoke.
No idea RZucker although anything is possible ? Dad & I are still scratching our heads on the C pull timing setting running good at 1.525 ? If I had it to do over again we should have checked the setting before pulling it all down but was in a hurry as we were in the middle of a job . Took about a half day to get it sorted out with adjusting the injectors & then grab a load of dirt to see how the engine performs ( trial & error ) . Probably had the valve covers off six times , luckily it only takes 30 seconds to remove the valve cover She runs fine , noticed a little more power after the rebuild , more than likely from good compression with the new pistons & liners .
It's been years since I've stuck my hands in any Detroit let alone a V8. I seem to remember that all N engines, those using N injectors had advanced cam timing and were set at 1.484. They started almost instantly and had a roar that was never heard anywhere in nature. As I recall all turbo charged engines that I had anything to do with ran retarded cam timing by one tooth. They usually had a can of ether somewhere nearby and always took good batteries and plenty of turning to get them to come to life. These were before the 92 models and all those I had anything to do with were green blocks. One thing I have seen that is not mentioned in this thread is the affect of an oil slugged muffler. More than once I've things like broken baffles and clogged up insides of a muffler really screw things up.
And also there could be two or more different things going on here. Wrong assembly of engine, timing or liners/pistons, injectors. Or a problem with what ever puts a load on this engine. Be it the air end, a hydraulic pump or a valve in either the air or hydraulic system. I agree with workshoprat92, the real problem is a bad or total lack of diagnosis right up front. Then everyone after that just started throwing parts and money at it hoping they would stumble on to the problem. Now this far down the road there will be no simple fast answer. One question I always liked to start with on any problem is "Did this happen fast or has it been getting worse over a long time?" Next, I try to find out what happened since the last time it worked good. Did someone change another component or jack up the pressure on something, dump some crap in the fuel tank, change the gears in the rear end to make truck go faster and now it won't climb the hills in top gear? I know this is not a truck but the idea is the same. I attended an air compressor school years ago and instructor told about the time he was called in to trouble shoot the failing air compressor his company had sold this factory. They had something like two 100 horse power electric compressors running this plant. As luck would have it the only chance he had to get there was on a Saturday when plant was shut down. Story went that they started up one of the compressors and even after running for a few minutes it could not reach cut-off pressure. Only with both compressors running would they get to the full air pressure. Long story short the only real problem with either of the compressors was there were so many "small leaks" throughout the factory it took over 100 hp just to supply them! After he convinced the manager that was the problem and they spent the next several weekends fixing leaks the plant was able to run just fine on one of the two compressors. Point being just because one item in a system does not seem to be doing it's job it could be it is fighting an uphill battle that it can not win.
Update on 8V92 Thanks for all the input. Do not what was wrong with the 9290 injectors that would not adjust to 1.484. Ordered in a new set, everything timed out well.Cranks easy and runs strong. Will test run Monday in the field.
So did the new injectors adjust to the 1.484 or did you set them to the 1.600?
yes 1.484 thanks
We have two 8v92T on our pilot boat which runs well but one is making brown smoke and when we check turbo rpm it us a difference of 3000 rounds as compared to the others means it is making low boost but both the engines are same also tuned similary and are kept at same place Can you tell me what the problem is
Do not thank brown smoke is on the low power trouble shooting flow chart. Always start with the simple stuff like filters. Do both engines operate off the same fuel tank? Can you send pictures?
I am to dang old to change from being goofy. I love the 2 stroke Detroit's. Whaaaat???
Is there any difference between camshafts lobe degrees of 8V92T and 8V92TTA