Camelback Posted November 24, 2007 Share Posted November 24, 2007 I have a 79 R-600 that came out with a maxidyne 300, In 1989 i retired the 300 and bought a brand new 2 valve 350 engine from a mack dealer. I swapped out the engine myself and after i got the 350 in i was running low on money and needing to get back to work so i put my 300 pump and injectors on the engine and went back to work. The engine runned fine considering it had a 300 pump and injectors on it. Then i built my money up to buy a brand new 350 injector pump and injectors to put on the truck thinking it would really run alot better. When i put the 350 pump and injectors on the 350 engine i actually lost a gear on the pulls, and to make it worse when you go to take off it will not idle off on its own without helping it with the throttle a little. The engine will actually die if you are loaded and don't help it out a little with the throttle. The truck is still running this way , we have just learned to drive it that way but i have never seen a diesel engine that will not idle off on its self. I have talked to several ppl about it and some says about all 350 pumps won't idle off and some says they have never heard of it before. I am running a 15 speed eaton transmission with 450 mack rears. Is this normal for a 350 pump or is something not right with this pump ? Quote Link to comment Share on other sites More sharing options...
Lmackattack Posted November 24, 2007 Share Posted November 24, 2007 is the timeing off? i believe the maxidynes had diffrent timeing than the econdynes?as far as not walking off the line easy, it could be a few diffrent things... low speed idle set to low, wrong timeing(low power) problem in the gov box... Maxidynes made more TQ down low so this was lost when you switched parts around to a 350 set up. the 350s make there power around 1450RPM and up they tend to fall on there face around 1350RPM.if you say you have power loss up top and down low than i susspect timeing issues... that is if all your 350 parts are correct and your fuel and filters are fresh. Quote Link to comment Share on other sites More sharing options...
Camelback Posted November 24, 2007 Author Share Posted November 24, 2007 Thanks for the info mackattack, my maxidyne pump timed at 22 degrees and the 350 encondyne if i member correct it said it timed at 23 rebuilt the engine 2 years ago and checked the timing because i was sure it was off, but it wasn't it was right on the money. the 300 pump had some fuel turned to it, and the 350 was set standard and after i cranked a little fuel to the 350 pump the power on the top end has been where it should be. as far as the idle setting i have set it up down and everywhere in between and it does not help a thing. She just always wants to fall on her face when u let that clutch out and it gets aggravating at times especially stopped loaded uphill. got to drive her like a gas model LOL !! Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted November 25, 2007 Share Posted November 25, 2007 is the timeing off? i believe the maxidynes had diffrent timeing than the econdynes?as far as not walking off the line easy, it could be a few diffrent things... low speed idle set to low, wrong timeing(low power) problem in the gov box... Maxidynes made more TQ down low so this was lost when you switched parts around to a 350 set up. the 350s make there power around 1450RPM and up they tend to fall on there face around 1350RPM.if you say you have power loss up top and down low than i susspect timeing issues... that is if all your 350 parts are correct and your fuel and filters are fresh. Mack sure that the stop cable is not pulled alittle bit when runing Quote glenn akers Link to comment Share on other sites More sharing options...
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