Boost and Rod Knocks
06-18-2009, 11:04 PM
#1
1.0 BAR
Thread Starter
Join Date: Jun 2009
Location: Chicago Il
Posts: 300
Boost and Rod Knocks
I was on the dyno today with the BEater and I was giving it the warm weather tune. all was going well then out of the blue my motor developed a rod knock after the last pull. I am not spinning to more than 6800 rpm and its a jdm sohc zc that looked fairly clean when I pulled the pan for the turbo install. never had any other problems. I was only at 202whp when it decided to do this. I am thinking just drop the pan pull the rod caps off see if the crank looks ok and put new bearings in it and cross my fingers. anyone else had this happen to them. I know that the turbo puts more stress on the oil film but the bearing size of the d series is the same as the ls/b20 motors and I put down more than 450whp out of my 2.0 with damn near the same bearing size
06-19-2009, 11:56 AM
#5
1.0 BAR
Thread Starter
Join Date: Jun 2009
Location: Chicago Il
Posts: 300
thats a good point. I was actually thinking that last night. I am going to rip it appart today and see what the bearings look like. I had rather thick 15w40 oil in it to try to keep as much oil film as i could
06-20-2009, 09:24 PM
#6
1.0 BAR
Thread Starter
Join Date: Jun 2009
Location: Chicago Il
Posts: 300
well lack of oil it was. make a rundown of the bearings. NO1 cyl this was the one that was knocking def oil starved nice and shiny bearing but the crank looks ok. NO2 also oil starved but not nearly as bad only has shiny spots at the top and bottom. NO3 no sign of oil starvation but all the bearing particles from no1 and 2 decided to embed in the bearing surface. and NO4 looked def the best however also had little particles of bearing embedded in the surface as well. I am glad this is a 1st gen d series with the much more robust oil pump because if this happened to a y8 i am sure there would have been crank damage. I am still curious why this happend now as opposed to 8 months ago when i built the car? I had plenty of oil in it. I think i am going to shim the oil pump with a .020 spacer and run 20w50 oil.
