Jmackaecker Posted September 29, 2016 Share Posted September 29, 2016 I got this here Mack at a job I just started. I'm semi new to diesel engines and to the JalTest software. To start this truck after its been sitting for a week or so I would need to use starting fluid to get it running, after that it runs and starts no problem till it starts. After I get it running to OP temp go to rev it up, 700 rpm all the way to about 1100 is ok, but when I go to past that it will start blowing smoke if I put the petal to the metal. I've also performed a cylinder test on a known running fine 690s truck in the image below. I'm not sure if those numbers are even up to. The test on the one smoking, the numbers ranged from 29 to 35, also tried a compression test using JalTest. I would be Cranking the engine over and the date would never show up on the screen. So I perform a compression test on the know good 690s and with in 5 sec of cranking I had info right away. Any Ideas?? Thanks in advance! Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/ Share on other sites More sharing options...
gearhead204 Posted September 29, 2016 Share Posted September 29, 2016 I'm not much on all the fancy tools, sounds like you either have a fuel problem or a compression issue, check the engine blow by tube (a monometer test) will tell if you have excessive blow by, if you do the engine needs rebuilt. if it is acceptable then have the fuel system worked on, the high speed smoking could be any thing from a plugged air filter to an injection timing issue, or faulty injector. to an intercooler issue. Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347281 Share on other sites More sharing options...
Jmackaecker Posted September 29, 2016 Author Share Posted September 29, 2016 Alright Ill Have and update tomorrow. thanks a lot for leading me in the right direction. Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347290 Share on other sites More sharing options...
fjh Posted September 30, 2016 Share Posted September 30, 2016 6 hours ago, Jmackaecker said: Alright Ill Have and update tomorrow. thanks a lot for leading me in the right direction. When u post post the color of the smoke black white blu al of these are indicators 1 Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347336 Share on other sites More sharing options...
Jmackaecker Posted September 30, 2016 Author Share Posted September 30, 2016 yes sorry its white smoke and an E7 350 engine Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347367 Share on other sites More sharing options...
Jmackaecker Posted September 30, 2016 Author Share Posted September 30, 2016 just seen that the turbo to manifold is leaking exhaust Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347383 Share on other sites More sharing options...
fjh Posted September 30, 2016 Share Posted September 30, 2016 Start with the fuel return check valve just behind the turbo drain tube that may correct your issue its relatively cheap! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347386 Share on other sites More sharing options...
turckster Posted October 1, 2016 Share Posted October 1, 2016 Check the fuel pressure, should be somewhere around 65 psi at idle. Usually when the fuel tansfer pump starts to give up the ghost the engine is hard to start, has white smoke in the upper rpms. The drive gear is most likely spinning on the drive shaft on the transfer pump. You might check the oil level as well, it could be diluted w/fuel--another thing the fuel transfer pumps were notorious for. Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347449 Share on other sites More sharing options...
fjh Posted October 1, 2016 Share Posted October 1, 2016 Yup good point ! Check this post as to where to take the preasure from 1 Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347450 Share on other sites More sharing options...
Jmackaecker Posted October 4, 2016 Author Share Posted October 4, 2016 Finally got around to installing the fuel psi gauge. Note that the psi is fluctuating between 55 and 85-90 because there is no in line valve to hold the value. would I still go off of the highest reading? The filters are new and the pump seems to be Farley new. Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347781 Share on other sites More sharing options...
fjh Posted October 4, 2016 Share Posted October 4, 2016 Is it still smoking with the gauge in? when you rev it up does the pressure drop off that is the whole point of this exercise! If not your looking in the wrong place!The preasure should drop a tad then jump up with a good stomp on the trottle! Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347785 Share on other sites More sharing options...
Jmackaecker Posted October 4, 2016 Author Share Posted October 4, 2016 installed the hose with the valve and the psi slims down to about 70psi. Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347787 Share on other sites More sharing options...
fjh Posted October 4, 2016 Share Posted October 4, 2016 Nothing wrong with that as long is the preassure is not droping off when you rev! Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347788 Share on other sites More sharing options...
Jmackaecker Posted October 4, 2016 Author Share Posted October 4, 2016 ok so I moved the gauge to correct port on the block. The needle is all over the place. It seems to run way better with gauge hooked up, and doesn't really have the problem any more. There is still smoke but more now when I let off the peddle after romping on it. I'm uploading a video to you tube. I'll send the link when it's done. thanks BTW for taking your time to help. also is this the check valve to check/replace? Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347795 Share on other sites More sharing options...
Jmackaecker Posted October 4, 2016 Author Share Posted October 4, 2016 Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347796 Share on other sites More sharing options...
Jmackaecker Posted October 4, 2016 Author Share Posted October 4, 2016 Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347797 Share on other sites More sharing options...
staxx Posted October 4, 2016 Share Posted October 4, 2016 Is it smoking at any certain rpm ? Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347806 Share on other sites More sharing options...
Jmackaecker Posted October 4, 2016 Author Share Posted October 4, 2016 (edited) yes it does, when holding rpms at about 12-1250 Edited October 4, 2016 by Jmackaecker Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347807 Share on other sites More sharing options...
Jmackaecker Posted October 4, 2016 Author Share Posted October 4, 2016 ok so I have the fuel return check valve out and it seems to be moving freely. Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347812 Share on other sites More sharing options...
Jmackaecker Posted October 4, 2016 Author Share Posted October 4, 2016 Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347813 Share on other sites More sharing options...
staxx Posted October 5, 2016 Share Posted October 5, 2016 Set the rpm with cruise switch to point were truck is smoking and loosen up injector lines one at a time . sounds like a failed injector to me . 1 Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347906 Share on other sites More sharing options...
Jmackaecker Posted October 5, 2016 Author Share Posted October 5, 2016 ok ill try that this afternoon. what am I looking for when I crack open the line? Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347911 Share on other sites More sharing options...
fjh Posted October 6, 2016 Share Posted October 6, 2016 (edited) Yup thats worth a try That will at least nail it down to a hole If the smoke dont go away after that u may very well have an ECU issue ! Also if you can, check the ambient air temp if you have a means ,we once had issues with sensor readings coming from that sensor which put the engine in a retarded timing at certain temps! its a long shot but something else to try! un plug the sensor see if the problem clears up! Edited October 6, 2016 by fjh 2 Quote Link to comment https://www.bigmacktrucks.com/topic/47082-06-mack-690s-smoking/#findComment-347966 Share on other sites More sharing options...
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