W124/OM603 Afterglow DIY - Page 3 - PeachParts Mercedes-Benz Forum

Bio300TDTdriver · #31 01-08-2009, 09:23 PM

Quote:

Originally Posted by C Holmes

Is it possible to roll back the odometer in one of these things?

Why would you want to do that?

C Holmes · #32 01-09-2009, 06:56 AM

Some vehicles do that like the Chev truck I drive at work. The plugs will kick in and out for a few seconds after starting to help with combustion and smooth out the idle when cold

Bio300TDTdriver · #33 01-09-2009, 11:21 AM

Quote:

Originally Posted by C Holmes

Some vehicles do that like the Chev truck I drive at work. The plugs will kick in and out for a few seconds after starting to help with combustion and smooth out the idle when cold

So do all Mercedes diesels form MY '90 on. And the ones that have had the after glow update or the violet wire update.

Jeremy5848 · #34 01-09-2009, 12:54 PM

Quote:

Originally Posted by C Holmes

Some vehicles do that like the Chev truck I drive at work. The plugs will kick in and out for a few seconds after starting to help with combustion and smooth out the idle when cold

"kick in and out?"

"stay on for awhile," yes.

kenstfelix · #35 01-09-2009, 03:01 PM

I added a switch for my violet wire afterglow mod. It was a little tight behind that part of the dash, but once I started there was no going back. And from where I sit, I can't see it. It works fine for me, flip it to "on" and it cuts the signal going through the purple wire and gives afterglow. Once the car is warm, leave it off.

pawoSD · #36 01-09-2009, 03:46 PM

Quote:

Originally Posted by kenstfelix

I added a switch for my violet wire afterglow mod. It was a little tight behind that part of the dash, but once I started there was no going back. And from where I sit, I can't see it. It works fine for me, flip it to "on" and it cuts the signal going through the purple wire and gives afterglow. Once the car is warm, leave it off.

That switch really gives it the 1900's early car controls look too.

I went the easy route and swapped in an actual afterglow relay long ago. (over 4.5 years ago) It glows for 2-3 mins every time....but the plugs don't seem to care....I haven't changed one in over 3 years...

C Holmes · #37 01-09-2009, 05:37 PM

Can the relay simply be swapped from a newer model without mods?

babymog · #38 01-09-2009, 06:26 PM

One of my CAT diesels had a heated intake, would cycle on and off as necessary when first started (not even that cold out).

Quote:

Originally Posted by Jeremy5848

"kick in and out?"

"stay on for awhile," yes.

babymog · #39 01-09-2009, 06:28 PM

On the 603 the temp-sensor has to be switched for one with 4 pins and the new pins wired to the additional wire on the new relay.

I believe it is the same with the 602 turbo relay.

Quote:

Originally Posted by C Holmes

Can the relay simply be swapped from a newer model without mods?

Bio300TDTdriver · #40 01-09-2009, 09:50 PM

Cummins engines also cycle the manifold heat off and on after the engine has started. I believe it is emissions related and not to smooth out the engine.

sixto · #41 01-10-2009, 02:47 AM

Quote:

Originally Posted by Jeremy5848

"kick in and out?"

"stay on for awhile," yes.

Oh yes. When I started the 97 'burb 6.5 after work today I watched the headlights pulsate dim and bright as the wait to start (glow) indicator in the dash flashed. The headlights stopped pulsating when the indicator stayed off.

Sixto
87 300D

sixto · #42 01-10-2009, 02:49 AM

Quote:

Originally Posted by babymog

On the 603 the temp-sensor has to be switched for one with 4 pins and the new pins wired to the additional wire on the new relay.

I believe it is the same with the 602 turbo relay.

Can you tap into the trans VSV sensor beside the thermostat like Jeremy did?

Sixto
87 300D

Jeremy5848 · #43 01-10-2009, 08:51 PM

Quote:

Originally Posted by sixto

Oh yes. When I started the 97 'burb 6.5 after work today I watched the headlights pulsate dim and bright as the wait to start (glow) indicator in the dash flashed. The headlights stopped pulsating when the indicator stayed off.

Sixto
87 300D

Interesting. Learn something every day! Thanks.

Jeremy

Jeremy5848 · #44 01-14-2009, 08:25 PM

Quote:

Originally Posted by charmalu

. . . Does the W124 have the black box on the left inner fender with the AC fan relay under it like the W123? the ice cube relay.

If it does, why not cut one out of a w123 at PNP, relay and the connector and some wire pig tail. then it would look factory and be protected under the box.
. . . Charlie

No, it doesn't. All (most? some?) of the relays are in a relay box that is part of the fuse box. With more work than I want to do, it might be possible to squeeze an extra relay in there but it would require running more wires than my installation, even though it doesn't look quite as stock.

Jeremy

Jeremy5848 · #45 02-06-2009, 08:55 PM

As suggested, I decided to move the afterglow relay to the fuse/relay box so that the appearance of the engine compartment was returned to stock. The '87 300D Turbo (W124, OM603) has a blank space in the fuse/relay box that's big enough to hold a small relay. Initially, I thought that I wouldn't be able to fish the wires through but after pulling the fuse box apart I decided it was possible.

The relay I chose is a standard Mercedes relay made by Hella (I didn't re-use the relay from the earlier part of this DIY). The relay came from an old Benz in the local junkyard. I made a socket for it from a six-pin Mercedes plug that was left over from my European headlight project. Only four of the six pins were used.

After removing both covers from the fuse/relay box, I pulled out N10, the "combination relay" to make room to see what I was doing. The afterglow relay sits in the empty location but its socket isn't attached like the other sockets are. I put a piece of foam pipe insulation around the relay so it wouldn't rattle around.

The four wires from the afterglow relay run through the fuse/relay box and out the front of it. The two wires from the relay coil (terminals 85 and 86) run to Y29, the transmission vacuum amplifier switchover valve. The other two wires connect terminals 30 and 87a (common and normally closed contacts) to the glow plug relay, where they split the famous "violet wire."

A cold engine means that S25/6, the 50C temperature switch in the water jacket, is closed. This sends power to the afterglow relay, cutting the violet wire and keeping the glow plugs energized for the full 30 seconds (in my car) regardless of how long I wait before starting the engine. Once the engine warms up past 50C, S25/6 opens, the afterglow relay closes, and the violet wire works normally – the glow plugs turn off once the engine starts.

Suggestions:
1. Disconnect the battery before tearing the fusebox apart.
2. The main cover to the fuse/relay box is held on with six captive screws. Each screw has a fiber washer that holds it to the cover. These often get lost or damaged and should be replaced if you can find new ones.
3. With the covers off, remove one screw at the front of the fuse holder (the rear is hooked onto the relay box – tilt the fuse holder up and it will unhook).
4. I don't recommend undoing all of the fuse wires. Just pull the fuse holder out of the way and tie it to something. I used a shock cord.
5. Use tubing to enclose the wires. This makes for a neat appearance and protects the wires from accidental damage.
6. Remember to put N10 back before you put the covers back on the fuse/relay box.
7. Now reconnect the battery and test your installation.

While I had the fuse/relay box open, I removed and stored K2, the headlight washer relay. When I installed Euro headlamps I removed the headlight washer system. Since the wires are still in the car, removing the relay prevents a short circuit.

Jeremy