Help! om603 jumped timing when replacing vac pump gear! - Page 3 - PeachParts Mercedes-Benz Forum

ah-kay · #31 10-14-2014, 06:11 PM

Quote:

Originally Posted by BenzTurbo

ok, i will inspect balancer first. will it come off with the allen bolts removed or do i need to remove the 27mm center bolt?

why? You have done nothing near the crank if I read everything correctly.

engatwork · #32 10-14-2014, 06:46 PM

Worst case you have probably moved it off the cam some. My advice would be to leave the crank alone and focus on getting the cams properly positioned. That crank bolt is a pia without the flywheel locking tool.

vstech · #33 10-14-2014, 07:35 PM

Quote:

Originally Posted by engatwork

Worst case you have probably moved it off the cam some. My advice would be to leave the crank alone and focus on getting the cams properly positioned. That crank bolt is a pia without the flywheel locking tool.

Are you saying that the engine will rotate with the cam timing off by 40 degrees?

BenzTurbo · #34 10-14-2014, 09:04 PM

I knew something was off when the IP locking tool went in with the balancer in no number zone

BenzTurbo · #35 10-14-2014, 09:12 PM

Is the harmonic balancer specifically tuned to a particular crankshaft? There is a 603 at my local pnp

Diesel911 · #36 10-15-2014, 12:56 AM

Quote:

Originally Posted by BenzTurbo

the IP is currently out now and the timing basket is holding the sprocket for it in place. i know i screwed up on the BTDC and ATDC. sorry bout that. but i'm still confused about the cam and crank timing. why wouldn't the marks line up? i don't want to destroy this engine on startup or something. am i checking it right?

The Camshaft and Crank are timed at OT (TDC) with the exception that timing Chain stretch could alter that a a bit if your Camshaft Gear is Keyed.

When the Fuel Injection Pump is timed using the Timing Locing Pin you need to be sure it is timed right after TDC on the Compression Stroke to 15 Degrees After Top Dead Center.
You don't want it 15 Degrees after TDC on the Exhaust Stroke.

If you are worried about Valves hitting Pistons before starting rotate the Engine at least 2 complete ratations in the Normal Direction of Rotation by Hand.
That way there is a good chance you would feel anything causing a problem

BenzTurbo · #37 10-15-2014, 06:08 AM

Quote:

Originally Posted by Diesel911

The Camshaft and Crank are timed at OT (TDC) with the exception that timing Chain stretch could alter that a a bit if your Camshaft Gear is Keyed.

When the Fuel Injection Pump is timed using the Timing Locing Pin you need to be sure it is timed right after TDC on the Compression Stroke to 15 Degrees After Top Dead Center.
You don't want it 15 Degrees after TDC on the Exhaust Stroke.

If you are worried about Valves hitting Pistons before starting rotate the Engine at least 2 complete ratations in the Normal Direction of Rotation by Hand.
That way there is a good chance you would feel anything causing a problem

i think my problem is the balancer being wrong. i understand how the timing marks SHOULD line up but they don't. IP timing is currently wrong for sure because that is where the chain jumped. that was no problem (i thought) because even if the chain stayed on the sprocket, it could have been a spline or so off when i slid the new timing device on so i planned to remove IP and proceed to set the timing on it. but now it is coming apparent that the numbers showing on the balancer just can't be right in my opinion. i can rotate the engine by hand with no interference and have done it many times. i don't see any point to proceed setting the crank at 15 ATDC on the balancer and trusting it to be correct for IP timing. does anyone know if the OM603 will rotate freely if the cam timing was actually off 45- 50 degrees? I really don't want to pull the cam or the timing cover if i don't absolutely have to. i already feel like i'm over my head now and i'm just hoping it is something with the balacer. if the engine will not rotate with the cam timing being off that far, i would feel safe saying the balacer is incorrect and not have to worry about destroying the engine attempting to start it.

vstech · #38 10-15-2014, 08:41 AM

Keep in mind the balancer being off position can cause issues also. I think next step is to pull #1 prechamber and rotate crank to verify TDC position

jay_bob · #39 10-15-2014, 09:15 AM

Agreed
There is a procedure in the FSM for this using a dial indicator.

I have been following this and I think something slipped along the way.

Time to start from scratch and validate your static timing the same as if you had just rebuilt the engine. You can't trust anything at this point.

BenzTurbo · #40 10-15-2014, 09:20 AM

Quote:

Originally Posted by vstech

Keep in mind the balancer being off position can cause issues also. I think next step is to pull #1 prechamber and rotate crank to verify TDC position

i don't have the tools to pull prechambers

is there any other way to verify TDC? which way should the dowls behind the balancer face when at TDC?

vstech · #41 10-15-2014, 09:41 AM

You can pull the glow plug, and fill the cylinder with oil, the. Rotate the engine and watch for the spillage to stop and reverse.

ah-kay · #42 10-15-2014, 10:56 AM

if you rotate the engine and you do not feel any interference then the cam and crank timing should be OK. I strongly believe they are. Piston will hit valves if it is off by 40 degree. I am not a heavy duty engine guy but I think your problem now is the IP timing only. I would hesitate to remove anything unless you fully understand what you are doing. Best of luck.

BenzTurbo · #43 10-15-2014, 01:11 PM

Quote:

Originally Posted by ah-kay

if you rotate the engine and you do not feel any interference then the cam and crank timing should be OK. I strongly believe they are. Piston will hit valves if it is off by 40 degree. I am not a heavy duty engine guy but I think your problem now is the IP timing only. I would hesitate to remove anything unless you fully understand what you are doing. Best of luck.

i completely agree but i also understand what vstech is saying. if you have any question about incorrect valve timing, start from scratch or confirm timing marks and TDC. i like the idea of filling the first cylinder with oil. i can do that. but if that turns out that the numbers showing on balancer are false for TDC, i would again be blaming the timing device. i of course have to use that to do IP timing so i'm just stuck even though valve timing is probably unchanged and ok.