190e won't start after Trans conversion - PeachParts Mercedes-Benz Forum

Chamorro · #1 10-29-2004, 01:55 AM

'90 2.6, used to be auto.
OK, after finally getting the manual tranny bolted up, we tried to see if the car would start. I took the electrical plug that used to connect to the auto tranny apart and wired the two neutral safety switch wires together.

The starter cranks but the engine doesn't turn over. We don't see spark coming out of the coil (tested by holding a screwdriver near the electrical connector of the coil wire while trying to start the engine). Same thing when supplying the coil w/ direct power from the battery. The fuel pumps work and we can smell gas when manually opening the throttle body valve.

Is something keeping us locked out of the coil? Could the coil go bad after about 3 weeks of the car sitting? Should I look elsewhere first?

Chamorro · #2 11-18-2004, 12:33 AM

....in case anyone's interested or has insight:

turns out I needed a spacer for the crank sensor (brand-new one was f'd up). Now the coil fires, but the engine still won't start. Mechanic buddy says it's as if there was too much timing retard.

So, there's fuel (can smell it), there's air (no air cleaner and the throttle body valve moves), and there's spark, but still the engine doesn't run. Any ideas?

tvpierce · #3 11-18-2004, 01:04 PM

I'm grasping at straws here, but...

Did you mess with the timing while making the tranny swap? You changed flywheels, right? Did you have to set the engine to top-dead-center? If so, are you sure you were on a power stroke, and not an exhaust stroke? This would make your timing 180-degrees off (ie: firing on the exhaust stroke)

Just a thought.

Jeff Pierce

Chamorro · #4 11-19-2004, 03:23 PM

Well, I don't think I did anything to mess with the timing; at least, I didn't do it on purpose :p. I didn't start the project at TDC, and each flywheel could only be installed one way, so I figured they should "look" the same to the crank sensor, sort of like a normal turn-off and re-start cycle.

Worth a look, but that would require pulling the tranny again....

.

tvpierce · #5 11-19-2004, 07:57 PM

Clearly that's not it. As I said, I was grasping at straws.

Good luck... and post back with any updates.

Jeff Pierce

psfred · #6 11-20-2004, 12:24 PM

You will need to compare the two flywheels (and ring gears!) to verifty that the crank position sensor is correct. If they are different, you may need the computer out of a manny tranny model to get the timing correct.

Peter

mpolli · #7 11-20-2004, 12:45 PM

Quote:

Originally Posted by Chamorro

and each flywheel could only be installed one way

Peter,

Is that correct? Didn't you just have a problem where the flywheel could be installed slightly "off"?

Mike

stevebfl · #8 11-20-2004, 03:00 PM

Quote:

Originally Posted by Chamorro

We don't see spark coming out of the coil (tested by holding a screwdriver near the electrical connector of the coil wire while trying to start the engine).

While the flywheel location would alter the timing, it wouldn't stop the creation of spark. That is unless the flywheel places the ring gear at a spot distant from the sensor.

hanno · #9 11-20-2004, 05:28 PM

Just to add my experience with 2 swaps... no trouble at all with flywheel position sensors. Both were installing a manual flywheel on an engine originally equipped with an automatic box. One was a 5 cyl diesel, other a 6 cyl. gasser. No computer problems, but both swaps used all donor parts from the same model year.

psfred · #10 11-21-2004, 02:12 PM

On the M116/M117 aluminum engines, the flex plate bolts to the ring gear at three points, evenly spaced around the circumference. It will bolt up in any position, but is marked by small holes in both parts for alignment. If you get it 120 degrees off, the crank position sensor pin on the ring gear will be either fast or late by 120 degrees, causing severe running problems.

I don't know what the arrangement is on the M102/M103 engine, but you CAN get the flywheel on wrong, the offset in the bolt holes is small enough that the neck on the flywheel bolts will allow installation at any position if you screw them partly in and wriggle it around. If you finger tighten each one as it goes in, the offset bolt won't go in if the flywheel is in the wrong position.

Steve: I believe he said he needed a spacer (or a different one) and now has spark but still a no-run condition. I assume this was to correct for the difference in thickness of the flywheels. If, however, the pin collided with the pickup before the spacer was installed, he may still have an erratic crank position indication.

I believe a timing check with a strobe light is in order here. If it's way off, something needs fixing.

Peter

Chamorro · #11 12-24-2004, 04:35 AM

Quote:

While the flywheel location would alter the timing, it wouldn't stop the creation of spark. That is unless the flywheel places the ring gear at a spot distant from the sensor.

In this case, no spark was created b/c the Sensor was too far away from its correct position after using the spacer; the spacer had to be shaved down a bit.

Quote:

I don't know what the arrangement is on the M102/M103 engine, but you CAN get the flywheel on wrong, the offset in the bolt holes is small enough that the neck on the flywheel bolts will allow installation at any position if you screw them partly in and wriggle it around. If you finger tighten each one as it goes in, the offset bolt won't go in if the flywheel is in the wrong position.

Just to defend my position that you can't install the flywheel incorrectly: I've attached a picture of the flywheel installed. You can see the 8 flywheel bolt heads. If you remove the flywheel, you will see 9 holes at the end of the crank. If you flip the removed flywheel over to see its other side, you will see 8 holes plus 1 "dowel pin" (for lack of a better term) between two of the holes and within the same arc.

Anyway, for a full story, check out this thread. The link is a post to the summary of what I've done, plus extra links that talk about the hiccups I encountered.