Walkyrie_Engineering Posted August 21, 2022 Share Posted August 21, 2022 I just recently replaced the head on our MP8. it went together fairly well, but when re-installing the timing idler gear and the cam shaft I accidently wiped off our timing mark on the backing plate, I had the cam set with the TDC mark in-between the hash marks but I am having doubts of whether or not i had it set on the driver side hash mark so now I'm paranoid I may be one tooth off in timing. the engine starts and runs, the first couple seconds after it starts its nice and smooth then it does a step down that its always done (like maybe a load kicks on or something) and it gets a clacking, it almost sounds like valve tap but it changes in frequency and smooths out a bit after idling for about a minute it gets a rough surging idle, there's a slight hesitation in acceleration but when idled up it runs smooth. and there is also a little bit of white smoke coming out of the exhaust. Am I off on timing a tooth, or could it be Injector rattle, or the new injectors need programed, or the valves need re adjusted? any advice is greatly appreciated. Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/ Share on other sites More sharing options...
Joey Mack Posted August 21, 2022 Share Posted August 21, 2022 did you plug the cam and timing sensors into the correct plug' on the back of the engine? if not you will have hard to start condition, it will start and run, but it wont like the throttle pedal.. I hope MackPro, get's in on this one.. jojo Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507082 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 21, 2022 Author Share Posted August 21, 2022 Just now, Joey Mack said: did you plug the cam and timing sensors into the correct plug' on the back of the engine? if not you will have hard to start condition, it will start and run, but it wont like the throttle pedal.. I hope MackPro, get's in on this one.. jojo Is there more than one plug? I plugged in the sensor on the timing gear cover did i miss another one on the back somewhere? unfortunately I'm not the one who took the back of the engine apart. Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507083 Share on other sites More sharing options...
Joey Mack Posted August 21, 2022 Share Posted August 21, 2022 Volvo saw it fit to have 3-4 plugs keyed the same.. so if you dint mark them before removal,, like me you may forget where they go.. just saying.. to get to these plug's, you need to remove all of the plastic covers around the pedals, and the big one ont the right side, then the center console, with the cup holders, then behind it will be a steel cover, with 10mm headed bolts all around it, and hidden under the edge of the rubber floor mat. . sorry bud,,, I can strip one in 20 minutes, just be patient.. then you will see the back of the head and valve cover.. the sensors are right there.. keep in touch if you dig into this,,, we will guide you.. jojo Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507088 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 21, 2022 Author Share Posted August 21, 2022 I still have that plate off, so I can get back there, and thank you I did find a unplugged wire it seemed to smooth out a little, but trying to restart the engine it didn't really like that, I have a video of it running but it's too large to upload. Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507091 Share on other sites More sharing options...
Joey Mack Posted August 21, 2022 Share Posted August 21, 2022 ok, switch the cam and hidden crank shaft plugs and try again... Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507093 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 22, 2022 Author Share Posted August 22, 2022 18 minutes ago, Joey Mack said: ok, switch the cam and hidden crank shaft plugs and try again... The crankshaft plug was never unplugged there was a white wire coming from the passenger side of the engine that only made sense to plug into the the harness that the camshaft plug came out of Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507095 Share on other sites More sharing options...
Joey Mack Posted August 22, 2022 Share Posted August 22, 2022 ok, I m rusty, but I think there are 4 plugs that are the same,, 7th injector, egr, cam, and crank... I did a harness a few months ago and didnt mark the plugs, so it was kind of a shell game, trying to figure out what my mistakes were.. LOL jojo Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507096 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 22, 2022 Author Share Posted August 22, 2022 yeah unfortunately our mechanic dropped the ball on us and I had the whole project dropped in my lap, so there are parts I disassembled and parts he did, and I'll admit I'm a little in over my head here LOL🤕 and this truck has Offroad tuning if you catch my drift so I cant take it to the dealer Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507099 Share on other sites More sharing options...
Joey Mack Posted August 22, 2022 Share Posted August 22, 2022 yep, I do... we see it here often.... Deletes dont work.. unfortunately, you are at your own devices.. I know there are guys out there that can help you, I just dont know where they are... Good luck to you, jojo 1 Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507101 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 22, 2022 Author Share Posted August 22, 2022 https://photos.app.goo.gl/HPRi2PrLsfg8fSkR8 Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507102 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 22, 2022 Author Share Posted August 22, 2022 I'd like to undelete it, but we bought it this way and I don't know how they did it and I'm afraid it'd cost a fortune that we don't have to get it running right. it appears everything is still hooked up, maybe its possible a new filter and a programing flash wile "cure" the delete but I just don't know enough about the system Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507103 Share on other sites More sharing options...
Mackpro Posted August 22, 2022 Share Posted August 22, 2022 I always seemed to get the cam gear a tooth off either way when doing head/cam job . I started using the cam timing tool and never had a problem. https://www.freedomracing.com/j-44514-b-engine-timing-kit.html?___store=default&gclid=Cj0KCQjw0oyYBhDGARIsAMZEuMstKXaxSdz6q2TO3MjL_8ZSRJs5c6rzxSV-w61Hq6M2SV2d1ygTAGEaAmnLEALw_wcB Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507169 Share on other sites More sharing options...
Joey Mack Posted August 22, 2022 Share Posted August 22, 2022 yep But the 'B' rod in the 'A' hole MP.. I wouldnt know how to time one correctly without the rod gauge.. Hell,,, its been so long, I would have to open my book to do it.. So glad you are here to help the MP owners... jojo Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507187 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 22, 2022 Author Share Posted August 22, 2022 6 hours ago, Mackpro said: I always seemed to get the cam gear a tooth off either way when doing head/cam job . I started using the cam timing tool and never had a problem. https://www.freedomracing.com/j-44514-b-engine-timing-kit.html?___store=default&gclid=Cj0KCQjw0oyYBhDGARIsAMZEuMstKXaxSdz6q2TO3MjL_8ZSRJs5c6rzxSV-w61Hq6M2SV2d1ygTAGEaAmnLEALw_wcB so you think it may be a little off timing then? Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507200 Share on other sites More sharing options...
Mackpro Posted August 23, 2022 Share Posted August 23, 2022 (edited) 6 hours ago, Joey Mack said: yep But the 'B' rod in the 'A' hole MP.. I wouldnt know how to time one correctly without the rod gauge.. Hell,,, its been so long, I would have to open my book to do it.. So glad you are here to help the MP owners... jojo I don’t remember if the D12 engine used the A gauge and the D11/13 and MP7/MP8 the B . Or the other way around. The carrying case had the instructions inside. If you try hard you can time the camshaft without pulling the upper rear timing cover but it was tight. Put the flywheel on 0 degrees. Put the cam TDC mark between the marks on the cam bearing cap. Then install the cam gear but not the Damper. Then the A/B tool goes on the gear and using the correct rod in either the A or B slot on the tool , the rod will line up with a hole in the gear timing plate on the back of the engine. If the rod doesn’t line up then remove the cam gear and go a tooth right or left till it does . Always use new cam gear bolts . They are the same part number as the injector hold down bolts usually. Common rail engines don’t have a damper on the camshaft and possibly take different bolts . I only did a few common rail cams and those were due to slipped lobes . At least they were hollow and half the weight of a non-common rail cam. Edited August 23, 2022 by Mackpro 1 Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507219 Share on other sites More sharing options...
Vmac3 Posted August 23, 2022 Share Posted August 23, 2022 7 hours ago, Mackpro said: I don’t remember if the D12 engine used the A gauge and the D11/13 and MP7/MP8 the B . Or the other way around. The carrying case had the instructions inside. If you try hard you can time the camshaft without pulling the upper rear timing cover but it was tight. Put the flywheel on 0 degrees. Put the cam TDC mark between the marks on the cam bearing cap. Then install the cam gear but not the Damper. Then the A/B tool goes on the gear and using the correct rod in either the A or B slot on the tool , the rod will line up with a hole in the gear timing plate on the back of the engine. If the rod doesn’t line up then remove the cam gear and go a tooth right or left till it does . Always use new cam gear bolts . They are the same part number as the injector hold down bolts usually. Common rail engines don’t have a damper on the camshaft and possibly take different bolts . I only did a few common rail cams and those were due to slipped lobes . At least they were hollow and half the weight of a non-common rail cam. Hello everyone. Its been a while, back from vacation. The D12 had the gauge as well. It was positioned to the "A position" on the gauge and the 11-13 and 16 used position B. Whenever I do/did a camshaft job I always ensure that the engine is set to TDC. Zero on the flywheel housing and TDC on the camshaft. Make sure you have the correct backlash between the idler and the cam gear, otherwise you will have serious issues. V 1 Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507246 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 24, 2022 Author Share Posted August 24, 2022 13 hours ago, Vmac3 said: Hello everyone. Its been a while, back from vacation. The D12 had the gauge as well. It was positioned to the "A position" on the gauge and the 11-13 and 16 used position B. Whenever I do/did a camshaft job I always ensure that the engine is set to TDC. Zero on the flywheel housing and TDC on the camshaft. Make sure you have the correct backlash between the idler and the cam gear, otherwise you will have serious issues. V What exactly are the symptoms of a bad backlash? Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507298 Share on other sites More sharing options...
Onyx610 Posted August 24, 2022 Share Posted August 24, 2022 https://f01.justanswer.com/Mikemcmillan77/e8702f01-27ef-4360-a632-19792eaa15ef_PV776-88941026.pdf Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507301 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 24, 2022 Author Share Posted August 24, 2022 3 minutes ago, Onyx610 said: https://f01.justanswer.com/Mikemcmillan77/e8702f01-27ef-4360-a632-19792eaa15ef_PV776-88941026.pdf I checked today, I believe the timing is good. TDC mark and fly wheel "0" mark line up perfectly, engine runs smooth and just fine at first start. but as soon as the oil pressure reaches about 40 psi a knock develops sounds like its coming from the top of the engine, for the life of me I cant seem to find the culprit I thought I had it when I discovered the number 5 cylinder Injector arm was missing the oil plug on the roller side and was gushing oil out, I replaced the rocker and no avail the knock is still there there doesn't seem to be any flat spots all the rollers seem fine the ran the overhead and all the adjustments were good the some of the exhaust ones may have been a a smidge loose but nowhere near enough to cause a knock i'd think, brand new rebuilt head, and injectors plus I'd think if it was the valves knocking it would be from ignition not a few seconds later... the only co-relation to the knock seems to be oil pressure. I swear I'm about to pull my hair out Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507302 Share on other sites More sharing options...
Onyx610 Posted August 24, 2022 Share Posted August 24, 2022 Have you tried cutting out an injector one at a time when this starts? Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507304 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 24, 2022 Author Share Posted August 24, 2022 I planned on trying that in the morning when i have daylight, it seems to be at about half the engine speed here's an earlier video, I fixed the surging at the end but the knock is the same On 8/21/2022 at 7:49 PM, Walkyrie_Engineering said: https://photos.app.goo.gl/HPRi2PrLsfg8fSkR8 Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507310 Share on other sites More sharing options...
Joey Mack Posted August 24, 2022 Share Posted August 24, 2022 does the knock go away after a few minutes, and stay gone? Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507359 Share on other sites More sharing options...
Walkyrie_Engineering Posted August 25, 2022 Author Share Posted August 25, 2022 Turned out to be injector Knock, runs nice and smooth now took it for a test drive up to the truck stop got a little smoke from exhaust,, got back home and just before i parked huge billowing clouds of yellowish white smoke poured out of the exhaust, I didn't recognize the smell, and no problems with the engine oil pressure, engine temp all fine. kinda seemed like it maybe came from the after treatment? 1 Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507376 Share on other sites More sharing options...
Onyx610 Posted August 25, 2022 Share Posted August 25, 2022 51 minutes ago, Walkyrie_Engineering said: Turned out to be injector Knock, runs nice and smooth now took it for a test drive up to the truck stop got a little smoke from exhaust,, got back home and just before i parked huge billowing clouds of yellowish white smoke poured out of the exhaust, I didn't recognize the smell, and no problems with the engine oil pressure, engine temp all fine. kinda seemed like it maybe came from the after treatment? Awesome! Def sounded like some bad injector knock. Glad to hear that’s all it was. After treatment system? I thought it was deleted? What was the fix for the injector knock? Quote Link to comment https://www.bigmacktrucks.com/topic/70324-2013-mack-chu-mp8-timing-advice-needed/#findComment-507377 Share on other sites More sharing options...
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