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-   -   Cured my sluggish 300E (http://www.peachparts.com/shopforum/tech-help/122221-cured-my-sluggish-300e.html)

r_p_ryan 05-01-2005 10:05 PM

Cured my sluggish 300E
 
I set the camshaft timing to spec on my 300e and found it made a big difference in acceleration. I aquired a second E in January and found it is much zippier and determined there was something not-right with the sluggish one.

I read up on the procedure in the CD and found that the cam was several degrees off. Flipping the cam sprocket alters the timing by 3 degrees. I recently replaced the timing chain and was careful enough to not skip any teeth. The problem was that the new chain had less shrinkage and altered the cam timing. It was a fairly straight-forward job and was not much more work than replacing the U gasket.

I am putting together a DIY for replacing the U gasket and I would highly recommend that if you have the top timing cover removed to check the cam timing. It is done by setting the engine to TDC at the forward diagnostic crankshaft position sensor and checking the cam to see if the TDC indicator aligns with a casting mark.

Robert

lino 05-15-2005 11:12 PM

Quote:

Originally Posted by r_p_ryan
I set the camshaft timing to spec on my 300e and found it made a big difference in acceleration.
Robert

Tell me more please. I find that my 300ce is sluggish. The engine is as smooth as silk and works like a dream, but it's extremely slow.

bigblue1 05-15-2005 11:59 PM

Alternative cure / EHA
 
Can I add that in recently having my EHA reset (0.4 - 0.45 bar) my M103 has been transormed.

The previous 1800-2000rpm flat spot during warm up has dissapeared and the pick-up is hugely improved. The engine is far more willing and responsive to more throttle. Like a new one!!!!

I may be imagining it but the change-down to a lower gear seems to have improved. Maybe the engine is now able to place the necessary demand on the gearbox forcing it to down-change.

I suggest you try this first.

lino 05-16-2005 12:46 AM

Quote:

Originally Posted by bigblue1
Can I add that in recently having my EHA reset (0.4 - 0.45 bar) my M103 has been transormed.

The previous 1800-2000rpm flat spot during warm up has dissapeared and the pick-up is hugely improved. The engine is far more willing and responsive to more throttle. Like a new one!!!!

I may be imagining it but the change-down to a lower gear seems to have improved. Maybe the engine is now able to place the necessary demand on the gearbox forcing it to down-change.

I suggest you try this first.

How do you reset the EHA?

r_p_ryan 05-16-2005 12:54 AM

I purchased a 92 300E (M103) back in January and found it was much faster than my 89 300TE. In the TE I had replaced the timing chain in December, as well as the valve seals, head gasket, de-carboned and lapped the valves. I was surprised to find no difference in performance afterwards. The '92 E starts out in first gear and the '89 TE starts out in second, but even with the TE set to first gear there was just no comparison. The E had ample power through the entire range of RPMS. The TE was very sluggish until it got to about 2200 RPM. Above that it had much more power. On the highway it was marginally slower than the E.

After resetting the cam timing the TE is just about as fast as the E from a start. It is now alot of fun to drive. The fuel milage is better, around 20mpg (50% town, 50% hwy).

Checking the cam timing is relatively simple. Remove the valve cover, set the crank at TDC. Look at the camshaft just in front of the #1 rocker arm carrier. If you don't see a small hole in the cam then turn the crank 360 degrees. The lobes on the cam should be pointing down at #1. Get the hole in the cam perfectly aligned with a casting mark on the #1 rocker carrier, but only turn the crankshaft clockwise (pulling the plugs makes this easier). Then take a look a the timing mark on the crankshaft. If it is more than a couple degrees off then I recommend adjusting it. This is about as involved as replacing the timing chain, so maybe a little more work than replacing the U gasket.

On a related topic, when I checked the cam timing on my '92 E I was shocked to see the timing was off by about 30 degrees. I couldn't beleive this so I double checked that the engine was actually at TDC by inspecting the piston in #1. In fact the diagnostic timing marks were way off so I used the piston as the guide. I suspect that if I had believed the engine was that far out of spec and recalibrated the cam timing that I would have had a piston-valve collision. I would guess that somebody replaced the harmonic balancer and didn't put it back on properly. Funny thing is that I purchased it from the original owner who had tons of documentation - all service and repair history was at the MB dealer.

I found that eliminating vacuum leaks made the tranny perform better also.

pmizell 05-16-2005 01:13 AM

Quote:

Can I add that in recently having my EHA reset (0.4 - 0.45 bar) my M103 has been transormed.
Note that this pressure (.45) is below system pressure .. upper chamber pressure.

A small hex screw on the EHA itself adjusts this pressure.

There's a thread on this topic located here.

Good Luck

:D

bigblue1 05-16-2005 01:19 AM

Adjust EHA
 
Plenty written on EHA if you do a search.

Adjustment requires setting up fuel pressure differential measurements using guages with fine enough calibration. It is detailed in the Service CD.

Best done to the book by an indie in my opinion once you know all other components of fuel system are AOK.

I can't speak highly enough for how this has improved the feel of the engine.

It is resetting to factory spec (0.4 bar) with 0.45 bar being suggested to compensate for an older engine. It is slightly richening the mixture. It would sem that my car was previously running excessively lean.

It involves a micro-fine adjustment.

89 300CE 153k kms


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