DETAILED Under Hood Pictures of '85 300D Vac lines. Any '85s in Rochester, NY?

[85MB300D]

I am trying to sort out the vacuum lines on my '85 300D. I do not believe they are where they should be, but I have no reference to correct the routing of them.

The vac schematics/diagrams that I have looked at do not help me much, as I believe some components were removed (like rubber fittings and such).

I would really, really appreciate it if someone with an '85 could email me a BUNCH of detailed photos on where EVERY line should go under the hood.

Or, what would be even better, is there anyone in the greater Rochester, NY area with an '85 300D that I could drive to and compare side-by-side with both hoods open?

That would be the best, however at this point I will try to do it based on photos if someone can help me out.

Thank you so much, you guys are all great!

-Brian
'85 300D
301,700

[Brian Carlton]

Originally Posted by 85MB300D

The vac schematics/diagrams that I have looked at do not help me much, as I believe some components were removed (like rubber fittings and such).

The vacuum schematics for you vehicle should be the only data that you are utilizing to determine if you are correctly plumbed or not. Looking at another vehicle will not necessarily confirm proper routing.

If you have trouble understanding the schematic..........that's a different problem.........and we can assist with that..........however, the schematic, with suitable modifications, is what will get the vehicle back to a proper configuration. On the '85, it has many components that operate the EGR and ARV...........none of which is required.

Here is your vacuum schematic:




If you have questions...........ask away.

[dmorrison]

PM me your email address and I email you some very large pictures of my sons 300D engine compartment. It might help. Lots of vacuum tubes and such.

Dave

[Brian Carlton]

Originally Posted by dmorrison

PM me your email address and I email you some very large pictures of my sons 300D engine compartment. It might help. Lots of vacuum tubes and such.

Dave

Did you simplify that system, Dave? Pull out the converter and the switchover valve? Most of it can be tossed...........

[dmorrison]

Car is original.

Dave

[raslaje]

Is vent filter (85) the same type as the primary fuel filter? That's what I have connected to the switchover valve (81) and the vacuum converter (84) on one end connected just like the schematic, but the other end of the filter not going anywhere just open to ambient air. Should that be connected to the VCV (65) such that it gets cabin air just like the VCV?
And what is the function of the vacuum converter (84)? From the schematic it looks like it sends either some vacuum or ambient to the EGR. Is that correct?
What's ARV?
Thanks.

[Brian Carlton]

Originally Posted by raslaje

Is vent filter (85) the same type as the primary fuel filter? That's what I have connected to the switchover valve (81) and the vacuum converter (84) on one end connected just like the schematic, but the other end of the filter not going anywhere just open to ambient air. Should that be connected to the VCV (65) such that it gets cabin air just like the VCV?
And what is the function of the vacuum converter (84)? From the schematic it looks like it sends either some vacuum or ambient to the EGR. Is that correct?
What's ARV?
Thanks.

Would you like to reconfigure the system so that it only operates the transmission.........and eliminate all the superfluous BS that is strictly for emission purposes?

If you do, than advise.........and I'll tell you.........step by step.......what to remove and what to leave.

Once you start, however, there will be no turning back.

[85MB300D]

Brian,

I'll bite on that one.

How do you eliminate "the superfluous BS that is strictly for emission purposes?"

Would like to hear the procedure.

Thanks!

-Brian

[Brian Carlton]

Originally Posted by 85MB300D

Brian,

I'll bite on that one.

How do you eliminate "the superfluous BS that is strictly for emission purposes?"

Would like to hear the procedure.

Thanks!

-Brian

1) Find item #84, the vacuum converter. You're going to pull all the vacuum lines and toss it in the garbage.


2) One line from the converter goes to item #60, the EGR valve. Remove this line and toss it.

3) One line goes to the vent filter, item #85. Remove this line and toss it.

4) Remove the line from the vent filter to to item #81, the switchover valve, and toss it.

5) Remove the Y connector and the vent filter and toss 'em.

4) Now, you've got an open Y connection at the vacuum control valve. Remove the Y connector and toss it. Connect the one remaining vacuum line (the vent line) to the vacuum control valve (where the Y was previously connected).

5) The one remaining line to the converter is the vacuum supply line. It comes from item 63, the vacuum orifice. Remove this line and toss it.

6) Plug the open Y connection just downstream of the orifice (or remove the Y connector completely and connect the remaining two lines).

7) Find the line from item #81 to item #71 and toss it.

8) The remaining line to item #81 is the supply vacuum. Remove this line and toss it. However, you'll need to plug the opening at the main vacuum line where this line was connected.

9) Pull out item #81 and toss it.


Now, don't we have a much cleaner engine compartment?

And, no, you don't have to worry that the loss of any of the aforementioned devices will cause your engine to explode.

[raslaje]

Originally Posted by Brian Carlton

Would you like to reconfigure the system so that it only operates the transmission.........and eliminate all the superfluous BS that is strictly for emission purposes?

If you do, than advise.........and I'll tell you.........step by step.......what to remove and what to leave.

Once you start, however, there will be no turning back.

Thanks for posting the instructions. Very clearly given. I'm going to pass for the near term since the engine power and transmission shifting is fine and I want to do some forum searching on some sort of coolant heater.

[Dee8go]

What are the lines in our vacuum systems made of? Are they metal, rubber, or what? Sorry if this is too elementary, but I know very little about my car at this point. Thanks for you indulgence.

[Brian Carlton]

Originally Posted by raslaje

Thanks for posting the instructions. Very clearly given. I'm going to pass for the near term since the engine power and transmission shifting is fine and I want to do some forum searching on some sort of coolant heater.

...........there goes 30 minutes of work for nothing..........that's why I asked the question originally............

[Brian Carlton]

Originally Posted by Dee8go

What are the lines in our vacuum systems made of? Are they metal, rubber, or what? Sorry if this is too elementary, but I know very little about my car at this point. Thanks for you indulgence.

They are a combination of plastic (referred to as "Tecalan") and rubber. Plastic for the long runs and rubber for the connections.

[85MB300D]

Originally Posted by Brian Carlton

...........there goes 30 minutes of work for nothing..........that's why I asked the question originally............

No worries Brian, I will most likely do it the next time I get under the hood and sort the PO's mess out.

Thanks for the post!

[Brian Carlton]

Originally Posted by 85MB300D

No worries Brian, I will most likely do it the next time I get under the hood and sort the PO's mess out.

Thanks for the post!

Good........hope somebody will get all that BS out from under the hood. The '85 is a nightmare and 80% of it is not necessary for proper performance of the vehicle.

The PO probably tried to simplify the system himself..........and may have been partially successful. You'll just need to complete that project.

Let me know how you make out.........or if you get stuck.