rustydog Posted February 8, 2014 Share Posted February 8, 2014 OK, CHARGING SYSTEM ISSUES CORRECTED..INSTALLED ALTERNATOR AS ADVISED BY ALL, (OR MOST); "MATCHED" SET OF MACK BELTS WEREN'T..THEY JUMPED..REPLACED....FUEL TANK PROBLEM CORRECTED..RE-INSTALLED AND FILLED UP..CHANGED ALL FUEL FILTERS, AND WANTED TO CHANGE OIL/FILTER BEFORE TRYING TO FINISH UP AND INSTALL FENDERS. CRANKED HER UP TODAY WITH NEW OIL, BELTS, ETC.....AND I ONLY GOT LIKE 20-25 PSI OIL PRESSURE!! ENGINE SOUNDS OK, NO KNOCKS, NOISES OR SUCH....COULD THE OIL GUAGE LINE BE CLOGGED UP?? I ALSO REMOVED AND CLEANED LOWER PAN/SCREEN WHEN OIL SVC. USED 15W40 FROM NAPA......ANY THOUGHTS?? 1 Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/ Share on other sites More sharing options...
gearhead204 Posted February 8, 2014 Share Posted February 8, 2014 re check gauge with a known good gauge. un thread fitting on block and test at block. Does oil pressure increase with eng. speed? does it decrease with eng. temp? Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231300 Share on other sites More sharing options...
rustydog Posted February 8, 2014 Author Share Posted February 8, 2014 re check gauge with a known good gauge. un thread fitting on block and test at block. Does oil pressure increase with eng. speed? does it decrease with eng. temp? GUAGE AND LINE BRAND NEW....USED TO READ UP TO 60PSI...SHE WAS HOLDIN STDY AT 20+...SEEMED LIKE STARTED TO GO UP AS ENGINE WARMED..NO MOVEMENT WHEN REVVED Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231332 Share on other sites More sharing options...
Freightrain Posted February 9, 2014 Share Posted February 9, 2014 Bypass spring stuck? 20 psi won't hurt it idling, but I would not drive it far. Quote Larry 1959 B61 Liv'n Large...................... Charter member of the "MACK PACK" Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231348 Share on other sites More sharing options...
BAD DOG Posted February 9, 2014 Share Posted February 9, 2014 Yeah sounds like the bypass spring on the plunger in the oil pump is a stuck. You'll need to take that part of the oil pump apart and check out the piston and the bore also make sure the piston moves freely in the bore, they sometimes seize or get scored maybe the spring is broke Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231363 Share on other sites More sharing options...
theakerstwo Posted February 9, 2014 Share Posted February 9, 2014 You didn't drop a rag in the pan when you had the screen down did you? Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231389 Share on other sites More sharing options...
gearhead204 Posted February 9, 2014 Share Posted February 9, 2014 sounds like the rest of you covered the bases Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231398 Share on other sites More sharing options...
rustydog Posted February 9, 2014 Author Share Posted February 9, 2014 Yeah sounds like the bypass spring on the plunger in the oil pump is a stuck. You'll need to take that part of the oil pump apart and check out the piston and the bore also make sure the piston moves freely in the bore, they sometimes seize or get scored maybe the spring is brokeIS THIS COVERED IN ANY OF THE WIKI TOPICS ON HERE?? I'M NOT THE BEST! Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231415 Share on other sites More sharing options...
Vladislav Posted February 9, 2014 Share Posted February 9, 2014 There's a bypass canal with a valve in fuel pump to get out extra amount of pressurized oil when revs are high or other reason.If the valve doesn't close well under normal conditions this follows a shortage of oil supply in the system.The way to go - open the pan and get to the pump. Quote Никогда не бывает слишком много грузовиков! leversole 11.2012 Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231420 Share on other sites More sharing options...
steamer Posted February 9, 2014 Share Posted February 9, 2014 Hi I think my b was kept running over the years with whatever leftover parts were around I put a new oil gauge in it that goes to 100 and when it was cold the gauge would go all the way around and stop on the wrong side of the pin. Mine had a spring in it for a 3 line filter with the regulator on the block on the side of the engine. But mine has a bypass filter. I ordered the right spring from the local mack dealer and it never came in so I called watts mack and they got me one of the last new ones in stock from a different dealer . A few weeks later my local dealer came up with one also. If you need a new spring I have an extra one I would be glad to send you. Dean Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231422 Share on other sites More sharing options...
rustydog Posted February 11, 2014 Author Share Posted February 11, 2014 Hi I think my b was kept running over the years with whatever leftover parts were around I put a new oil gauge in it that goes to 100 and when it was cold the gauge would go all the way around and stop on the wrong side of the pin. Mine had a spring in it for a 3 line filter with the regulator on the block on the side of the engine. But mine has a bypass filter. I ordered the right spring from the local mack dealer and it never came in so I called watts mack and they got me one of the last new ones in stock from a different dealer . A few weeks later my local dealer came up with one also. If you need a new spring I have an extra one I would be glad to send you. DeanDean..sent you a pm Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-231888 Share on other sites More sharing options...
rustydog Posted February 20, 2014 Author Share Posted February 20, 2014 Yeah sounds like the bypass spring on the plunger in the oil pump is a stuck. You'll need to take that part of the oil pump apart and check out the piston and the bore also make sure the piston moves freely in the bore, they sometimes seize or get scored maybe the spring is brokeUPDATE....DISCONNECTED GUAGE LINE BOTH ENDS..BLEW OUT W AIR..NOTHING BAD ..STARTED UP WENT UP TO 60 FOR ABOUT A MINUTE, THEN DROPPED TO 20-25PSI..REVVING MADE NO DIFFERENCE, NO PRESSURE/OIL SQUIRTING OUT OF BYPASS FILTER WHEN PLUG LOOSENEDREMOVED PAN....SPRING INTACT, PISTON PULLED OUT EASILY...NOT SURE WHERE TO GO FROM HERE???? Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-233644 Share on other sites More sharing options...
steamer Posted February 20, 2014 Share Posted February 20, 2014 Hi Rusty I sent a relief valve spring the other day is it possible that the oil is draining out of the oil filter when shut down making it look like the engine is full of oil but when running the filter fills and the engine is low. I think the filter holds about two gallons. My b has a bypass filter but it is mounted to the frame behind the cab and I think is to low to drain back. I think there is a valve in the filter to keep it from draining back also could. The lines be reversed. Dean Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-233711 Share on other sites More sharing options...
rustydog Posted February 20, 2014 Author Share Posted February 20, 2014 Hi Rusty I sent a relief valve spring the other day is it possible that the oil is draining out of the oil filter when shut down making it look like the engine is full of oil but when running the filter fills and the engine is low. I think the filter holds about two gallons. My b has a bypass filter but it is mounted to the frame behind the cab and I think is to low to drain back. I think there is a valve in the filter to keep it from draining back also could. The lines be reversed. DeanDEAN.....GOT THE SPRINGS YESTERDAY....THANK YOU VERY MUCH...WILL BE SENDING YOU A CHECK TOMORROW....I DID USE ONE OF THEM AND WILL HAVE HER BACK TOGETHER TOMORROW, THINK I GOT IT FIGGERD OUT..RUSTY Quote Link to comment https://www.bigmacktrucks.com/topic/34602-now-what/#findComment-233745 Share on other sites More sharing options...
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