Dtech Posted July 13, 2023 Share Posted July 13, 2023 I got a basket case here and could use some help. I Have a customer that did a out of frame overhaul on a 1995 ch series E7 because a rod bearing failure taking out the crankshaft. I am not sure about the whole story this is all I have been told. However now the motor has low power since the overhaul. Truck will only go 45 mph with a trailer on flat ground. No smoke only 8lb of boost. The intake, turbo and air charge cooler have all been checked for leaks, The engine has no Active codes and goes to 100 load according to the scanner. Fuel psi is 28 psi under load, air filter and exhaust restrictions have been checked. First Question, I see no Intake Psi sensor sensor only air temp, two wire sensor is the only sensor in the intake manifold. Does E7 not have a intake psi sensor sometimes? I can not find a three wire plug anywhere on the engine harness for a intake psi sensor or a parameter for it on the scanner? I have not ruled out injection pump having issues do the metal in the oil from the rod bearing however, I would like cross off other possibilities before sending it off. The engine starts right up and idles fine just no power. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/ Share on other sites More sharing options...
doubleclutchinweasel Posted July 13, 2023 Share Posted July 13, 2023 There are 3 or 4 guys on here that will chime in pretty soon. I'm sure they will give you some good troubleshooting tips. And, welcome to The Dog Pound. Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-534758 Share on other sites More sharing options...
Joey Mack Posted July 13, 2023 Share Posted July 13, 2023 Was the cam removed? I assume you have an electric plug at the gov. Housing on the injection pump? Those pins can get loose.. was the valve adjustment done correctly, the Mack way and not the Cat. way? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-534762 Share on other sites More sharing options...
Dtech Posted July 13, 2023 Author Share Posted July 13, 2023 yes Cam was changed and customer has no idea what cam they used! Is the cam number on the front of the cam. Not sure about the valve lash we have not done it. Customers mechanic did it. Can it be that far out to be this low on power? It does have the electric plug I did look at the pins at the Deutsch round connector could not find anything obvious. It will not run and throws codes if I unplug it? are the pins you are talking about inside the governor housing? Should the valve adjustment be the first thing I need to check? Also saying the Cat. Way are you referring to using valve overlap on cylinders 1 or 6? Vs Macks 3 120 deg marks? Thanks for the help. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-534767 Share on other sites More sharing options...
Joey Mack Posted July 13, 2023 Share Posted July 13, 2023 yes to the valve adjustment.. You have to start on #1 (#2 exh. rocker is rocked) then roll the engine around 2 full times and setting the valves according to firing order..... ''Too Young-- Too old-- Just right! 15-36-24....does it have 680 Jake brake heads? the flywheel markings are ... 1&6-- 2&5--3&4... Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-534776 Share on other sites More sharing options...
Dtech Posted July 13, 2023 Author Share Posted July 13, 2023 yes it does have 680 Jake brake Housings Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-534778 Share on other sites More sharing options...
Joey Mack Posted July 13, 2023 Share Posted July 13, 2023 are you familiar with the markings on the flywheel? I expect valve lash to be int..016'' exh. .028''.... exh. valves are to the front of each cyl.. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-534779 Share on other sites More sharing options...
JoeH Posted July 14, 2023 Share Posted July 14, 2023 I'd suspect valve adjustment and also injection pump timing... Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-534786 Share on other sites More sharing options...
Dtech Posted July 17, 2023 Author Share Posted July 17, 2023 Injection pump timing has been checked and set. I am working on valve timing today. Does anyone know the answer to my question about the intake Psi sensor? Does E7 sometimes have them? I can not fined one on the engine harness or codes for one or find one with the scanner. It seems like the ECM would need that info! Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535068 Share on other sites More sharing options...
Joey Mack Posted July 17, 2023 Share Posted July 17, 2023 Your engine may be too old for that sensor.. there is probably a reversing relay in the intake with air going to it and a small line going to the Bimber valve on the front of the injection pump. It controls the rack based on boost pressure.. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535071 Share on other sites More sharing options...
Dtech Posted July 17, 2023 Author Share Posted July 17, 2023 I don't see anything like that on this one. I Have seen it before on older models, however this has electric wires going into the pump, no lines leaving the intake Manifold besides the air compressor air supply line. The only sensor is a two wire intake air temp sensor. I found a new pipe plug in a port that made me think he missed the sensor when rebuilding it. Some info on the truck Vin 1M2AA13YXSW058895. 1995 E7 -350hp engine ser# 5F2052. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535077 Share on other sites More sharing options...
Joey Mack Posted July 17, 2023 Share Posted July 17, 2023 nope.. you dont have it, i think what you have is econovance, and my knowledge on this is weak.. Sorry, I guess you have an electric plug on the injection pump.. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535079 Share on other sites More sharing options...
Dtech Posted July 17, 2023 Author Share Posted July 17, 2023 Joey You said that the pins and come loose. Are you talking about inside the pump? or on the electric round connector? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535080 Share on other sites More sharing options...
Joey Mack Posted July 17, 2023 Share Posted July 17, 2023 the round connector. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535081 Share on other sites More sharing options...
Dtech Posted July 17, 2023 Author Share Posted July 17, 2023 We will have a bay open soon so I can run the valve lash finally lol. I will check the plug with some back prob pins also. The timing advance solenoid has oil dripping from it. Would the ECM throw a code for Timing not changing? I guess I can put a timing light on it and watch what it does on the RPM curve. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535082 Share on other sites More sharing options...
Joey Mack Posted July 17, 2023 Share Posted July 17, 2023 it is a simple ECM.. back probes are not needed, just unplug it and look... check the condition of the wires on the back of both plugs looking for cracked insulation and frayed wires.. is the holder for the plug still mounted on the inj. pump? it needs to be there.. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535083 Share on other sites More sharing options...
Dtech Posted July 18, 2023 Author Share Posted July 18, 2023 Well I got the chance to check the valve adjustment and it was spot on. However I use the Camshaft timing check procedure in the book using #3 intake valve. I end up at 34 deg's The chart in the book said 27 deg's for cam part # 5205, 26 deg's #5142, 20 deg for part # 583, 583A. The book said I should be +- 3 deg's. Can anyone tell me off my engine ser# what cam part # I should have in this motor? Engine ser# 5F2052. The customer has no record of what was put in it! I could use some advice but I feel that the camshaft to crankshaft timing might be off? Also on my test drives the Jake brake does not seem to hold back well at all. However I am building very little intake psi 5 to 7 psi so its hard to judge it, but to me this also points to cam and crank timing being off. Thoughts Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535147 Share on other sites More sharing options...
Joey Mack Posted July 18, 2023 Share Posted July 18, 2023 it seems that you are at the least, 7 degrees off. you reckon, you will pull the timing cover and check it? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535148 Share on other sites More sharing options...
Dtech Posted July 19, 2023 Author Share Posted July 19, 2023 Yes but I would also like to install my timing light and find out what exactly the timing is at now, and what it is going to at high rpm. I don't understand how he could have gotten in off? Does it not have marks on the two gears? 🤔 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535158 Share on other sites More sharing options...
Joey Mack Posted July 19, 2023 Share Posted July 19, 2023 It has marks. Did you find one of those timing tools? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535163 Share on other sites More sharing options...
Dtech Posted July 19, 2023 Author Share Posted July 19, 2023 Well I eating some humble pie this morning I made a mistake yesterday my dial indicator was hitting the Jake housing so I got a false reading. Its hard to see the timing marks and watch the indicator at the same time. So the cam Timing is correct at 27 deg's Mack dealer said the cam part # is a 454605142. According to the chart its on the money. This one has me stumped we crossed off intake leaks, exhaust restrictions, Turbo, valve lash, camshaft timing, injection pump Timing, and fuel psi. Even if they installed the wrong cam I don't believe it would be this low on hp. Its a complete dog! I looked at the injection pump rack Travel, it does not hang if I start it with out the computer controlling it will defiantly put the fuel to her. So it has the ability to run well. I don't understand why I can't find the intake psi sensor? Mack dealer said its sensor 20705960 boost/temp sensor. I am confused it is only a two wire sensor how can it have two circuits with only two wires? If I unplug it I get a active code for intake air temp. Nothing for boost. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535198 Share on other sites More sharing options...
Joey Mack Posted July 19, 2023 Share Posted July 19, 2023 forgive me with asking about valve adjustment several times.. To me adjusting valves on a Mack engine NEED's to be followed by the book.. I have done several Cat's and John Deere's, and you can run the valves on several cyl's with each position.. On a Mack, you position the engine ''up on #1'' and run the whole cylinder, then move to the next in the firing order.. You obviously have a good skill set. Jojo 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535201 Share on other sites More sharing options...
Dtech Posted July 20, 2023 Author Share Posted July 20, 2023 No I understand the importance of the valve adjustment. I apricate the help any Idea on the temp/boost sensor? Why would Mack and Pai list it as a dual sensor? I am lost on how this works only using two wires. When I ohm the sensor it has continuity between the two post, and it changes with temp. part # 20705960. Does anyone have a ecm wire diagram for the engine sensors? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535265 Share on other sites More sharing options...
Joey Mack Posted July 20, 2023 Share Posted July 20, 2023 I may have a pin out diagram at home. It will be a few hours or so before I can look. I believe you have a '96 E-7 350 V-Mac II. ? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535266 Share on other sites More sharing options...
Dtech Posted July 20, 2023 Author Share Posted July 20, 2023 yes you are correct on the info thanks! Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/#findComment-535269 Share on other sites More sharing options...
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