Been working on an engine swap for awhile now. Putting a D905 into a Bx. Having trouble starting after all this work, and I'm thinking it's a timing issue. I have verified all 3 sets of dots line up on the gears, so I don't think that's it. The engine won't start unless I use glow plugs, and even then its definitely missing enough to not start.. I'll post a video below of what it sounds like following this.
I've rebuilt some of this so far, new rings, big end bearings, hone in cylinders and mic'd +- 0.01mm from spec (72 mm) in 6 spots all cylinders. Cleaned the pistons and rods in an ultrasonic and replaced the flat tappets because I turned the engine over pulling pistons and they all came out and got mixed up. I've had a shop clean up the head. They cleaned and lapped the valves. Put in new stem seals. Got the head back on with a new head gasket and the small oil o ring. Compression looks good cold, right at 400psi for all. I've pop tested and leak tested all injectors, pops right at 1900psi. Holds that pressure too for 10 seconds. Injection timing is right at 20 degrees btdc. And I've verified this for all cylinders with a dial indicator. Used spill timing method. So I don't think injection timing is to blame. I've also verified cylinder #1 TDC matches the flywheel mark with the dial indicator, so I don't think it's bent connecting rods.
Originally this engine was a fixed rpm BG type and its timing was set a bit retarded from spec. From what I remember around 10 degrees. Which is weird, because I was able to start it like that in my determining whether this engine was a good candidate for a swap, before doing any of the aforementioned work.
So at this point I've been checking angles relative to bdc tdc when valves open/close to see if maybe my camshaft is to blame.
According to the WSM:
Intake valve begins opening 14 degrees before TDC of exhaust stroke
Intake valve begins closing 30 degrees
after BDC of intake stroke
Exhaust valve begins opening 55 degrees before BDC of power stroke
Exhaust valve begins closing 14 degrees after TDC of exhaust stroke
I've measured the following so far:
#1 IV opens 2 degrees BTDC
#1 IV closes 30 degrees ABDC
#1 EV opens 40 degrees BBDC
#1 EV closes 4 degrees ATDC
#2 IV opens 8 degrees BTDC
#2 IV closes 30 degrees ABDC
#2 EV opens 50 degrees BBDC
#2 EV closes 14 degrees ATDC
#3 IV opens 5 degrees BTDC
#3 IV closes 30 degrees ABDC
#3 EV opens 50 degrees BBDC
#3 EV closes 18 degrees ATDC
I remeasured cylinder #1's valves and got different results from the first time
#1 IV opens 7 degrees BTDC
#1 IV closes 30 degrees ABDC
#1 EV opens 35 degrees BBDC
#1 EV closes 4 degrees ATDC
I'm sort of blaming these unprecise measurements on the digital dial indicator, and am currently waiting on an analogue one that is more accurate. I will remeasure all 3 cylinders again with the digital dial indicator and post here.
Just wondering if maybe I've overlooked something or whether someone else has ever measured valve angles and can spot something wrong right away or maybe something I'm doing wrong.
I've rebuilt some of this so far, new rings, big end bearings, hone in cylinders and mic'd +- 0.01mm from spec (72 mm) in 6 spots all cylinders. Cleaned the pistons and rods in an ultrasonic and replaced the flat tappets because I turned the engine over pulling pistons and they all came out and got mixed up. I've had a shop clean up the head. They cleaned and lapped the valves. Put in new stem seals. Got the head back on with a new head gasket and the small oil o ring. Compression looks good cold, right at 400psi for all. I've pop tested and leak tested all injectors, pops right at 1900psi. Holds that pressure too for 10 seconds. Injection timing is right at 20 degrees btdc. And I've verified this for all cylinders with a dial indicator. Used spill timing method. So I don't think injection timing is to blame. I've also verified cylinder #1 TDC matches the flywheel mark with the dial indicator, so I don't think it's bent connecting rods.
Originally this engine was a fixed rpm BG type and its timing was set a bit retarded from spec. From what I remember around 10 degrees. Which is weird, because I was able to start it like that in my determining whether this engine was a good candidate for a swap, before doing any of the aforementioned work.
So at this point I've been checking angles relative to bdc tdc when valves open/close to see if maybe my camshaft is to blame.
According to the WSM:
Intake valve begins opening 14 degrees before TDC of exhaust stroke
Intake valve begins closing 30 degrees
after BDC of intake stroke
Exhaust valve begins opening 55 degrees before BDC of power stroke
Exhaust valve begins closing 14 degrees after TDC of exhaust stroke
I've measured the following so far:
#1 IV opens 2 degrees BTDC
#1 IV closes 30 degrees ABDC
#1 EV opens 40 degrees BBDC
#1 EV closes 4 degrees ATDC
#2 IV opens 8 degrees BTDC
#2 IV closes 30 degrees ABDC
#2 EV opens 50 degrees BBDC
#2 EV closes 14 degrees ATDC
#3 IV opens 5 degrees BTDC
#3 IV closes 30 degrees ABDC
#3 EV opens 50 degrees BBDC
#3 EV closes 18 degrees ATDC
I remeasured cylinder #1's valves and got different results from the first time
#1 IV opens 7 degrees BTDC
#1 IV closes 30 degrees ABDC
#1 EV opens 35 degrees BBDC
#1 EV closes 4 degrees ATDC
I'm sort of blaming these unprecise measurements on the digital dial indicator, and am currently waiting on an analogue one that is more accurate. I will remeasure all 3 cylinders again with the digital dial indicator and post here.
Just wondering if maybe I've overlooked something or whether someone else has ever measured valve angles and can spot something wrong right away or maybe something I'm doing wrong.
