still can't get to run

[jim 56]

Hi all.I have been trying to get my 1972 280 SE with a M130 engine to run right.I have gotten some help here and checked other posts but still can't get it.It will start and the rpm is smooth but low around 700.When I do the split linkage opening the throttle plate it will stall.open fuel pump does nothing.Moving them together it will increase but cough and backfire a little.I have loosened the BC as DR benz suggests so it can get richer still nothing.
1)I have taken and replaced the WRD thermostat.When I submerge it in water it will shut off air.When I install it in the car I know it gets hot but it still will not shut air completely.The RPMs do drop a lot and the temp gauge inside the car reads 190 degrees (is it possible I have the wrong thermostat for the radiator?)
2)My manifold vacuum seems low 14HG I have disconnected and plugged the lines going to the brake booster and the line going to something else I believe the door locks.
3)The timing at idle is I believe 5deg. before TDC I'm not sure but looking from the front of the car at my pulley there is notches to the left for 5 10 15 and 20 degrees.to the right 5 10 15 20 25 30 35 40 45 50 so I'm assuming to the right is BTDC.I cannot get the car to increase idle to see what the timing is at higher revs as JA 17 suggests.
4)I have a gauge in the fuel filter that is reading 11psi.I have an aftermarket fuel pump in that did have 13 psi and flow rate higher than the 1.5 liter in 15 seconds(it has been in the car only a month)I'm pretty sure that I read here that the car should run at idle at least with that.My original short pump is having it's armature rewound now hopefully it will done soon and I will put new brushes and seals in.
5)I put in new points and condenser.I can't tell the dwell as my dwell meter broke but points are gapped at 16.The wires are new they say BWC silicone with copper core(doesn't say solid copper)each wire ohms at 1000.The coil is aftermarket(PVL) but has a bosch crossover number of 0221122001.The system is a transistor type.Distributor is number 0231 116 068 (j1u6)BTW I do not see that number anywhere on any lists the highest I see only goes to 067.
I have a new crane xr 700 to put in but am a little bit afraid to put it in until i have the car running right but maybe I should install it if anyone feels the old system may be my problem.
I know this is a lot to ask but I really need some direction I really appreciate any help the experts can give me.
Thanks in advance

[ja17]

What is the history of the car? Did it rum before or has it been in storage?

[behnamlaw]

Did you also test your vacuum advance

[jim 56]

yes the car ran but was way too rich.Plugs would foul after a month or so.I would clean them and run them again.I drove it for a couple of months with a different aftermarket pump that the previous owner had put in.That pump went bad He had given me the original short fuel pump the impellar was bad I bought a new one and that ran for a while until the windings started getting too hot.I put in a new aftermarket pump from Jeggs.The new pump had 13.5 psi and a higher flow rate I forget exactly.Then I joined this group.So I started following different lines of advice.One thing is that I put in hotter plugs NG 5 es I think is the number.I took out csv valve and made sure it was working not leaking etc.Like I said in my post the WRV I took apart made sure slide moved freely put in a new thermo(I had to drill collar to 13mm )tested it in hot water.I have also taken out the injectors and backflushed them.I took apart the vac advance plate it was stiff now when Isuck it moves freely.Like I said I found someone on this site that rewinds armature for fuel pump(I would have never put aftermarket in if I had found him earlier)I should have pump next week

[Cees Klumper]

Just some loose thoughts based on your symptoms:
- I would slightly adjust ignition timing 'trial and error' as the engine is running, just turning the distributor a little bit by hand in both directions, see if this improves things
- I wonder whether all linkages are tight and adjusted right
- also whether you have good and even compression on all cylinders
- any vacuum leaks?
- is the engine timing good? Skip a tooth on the timing chain maybe?

[jim 56]

I have the linkages apart for doing the split linkage test but the throttle is on it's stop and plate is completely closed.Also the FIP is on it's stop when I put them together the Fip linkage rod is 233mm.I still am not sure what manifold vac should be as I said it is 14 and steady.I adjusted timing slightly and it didn't seem to matter that much.I haven't done a compression test yet but as I've said it was running.One thing that bothers me is that the WRD still sucks air and I believe that this is causing it to run too lean yet out of the car when I test it shuts off air.Is there something that would prevent the valve from completely closing air when mounted on the car?

[gcw206]

I had exactly the same issue with my 1969 280SL.  I went down the lengthly list of possibilities, corrected any deficiencies, but nothing seemed to make any difference.  Then I took the injector pump thermostat out, tested it in hot water; it worked correctly, but just did not "look right".  After some research work, I discovered that the new IPT sold by MBZ are a larger diameter than the old models.  If you use a newer IPT with the older model IPT seal ring collar, the IPT will not seat correctly on the collar, and as such, will not close properly.  (The new IPT sits above the old collar, instead of down in the collar; mine had evidently been that way for quite some time, because the IPT rod was actually slightly bent to one side.)  You can alter the old collar to accept the newer IPT; however, I bought one from Authentic Classics for $32.00, installed it with a new MBZ IPT, and the problem went away.

[jim 56]

Yes I saw the difference in the new opt I had to drill out collar so opt sat right.when I set it in hot water it does close air valve.i was wondering what radiator thermostat what temp should it be because mine reads around 190 I think that is too high

[Cees Klumper]

A too high thermostat rating would not cause the issues you describe. Did you check the other suggestions provided here?

[Benz Dr.]

Although it's normal to accept new parts as functional they may not be. Check your coil wire it could be carbon core. Dwell angle is 30 degrees on aluminum distributors so you should look at that. Go back to what you did or changed because your answer will be found there.

[Johannoren]

I recently had the very same issue with getting our 1969 280se to run after sitting since 1991.
Once we put in a new Injection pump, rebuilt fuel pump, cap, rotor, plugs, wires and cleaned the fuel tank it started and ran great.  After a few hundred miles it all of the sudden started acting up and miss firing.
I spent a few months going over everything AGAIN in the fuel system with no luck. I then tied another new cap and rotor, points and condenser but it still would just barely run.
The last thing I did was I ended up putting in a electronic ignition upgrade and she instantly ran perfect.  I know it's not "correct" for the car but now it runs great!

[jim 56]

I am going thru everything again now .Checked compressiong first 150 each cylinder very little difference.Checked valves all ok.Waiting for rebuilt armature now then will rebuid fuel pump.I have the crane will put that in soon.Thank you for replying.

[col320ce]

I've had something similar...
The wrd needs to shut off or you can't tune the car. Add more round shims... I think the average is 1.3mm required. My car runs cool so it would shut off with boiling water but really needs to shut off around 65 or so deg c.
I then drove my car to get it warm, removed all the washers under the bc and did the split lincage test at high idle unscrewing the bc until it was correct. Then adjusted the fip Idle thumb screw.
My theory is the bc governs fuel at all rpms and the thumb screw only idle so the bc needed adjusting first.

[Dave H]

Just going through mine trying to get it running right after rebuild.
Couldn’t get it to do anything right and no amount of adjustment of the injection pump would cure it, turned out to be a failed Barometric compensator, this topic has been covered before, BC fails with the pin fully deployed making the car impossibly lean thinking it’s at 42000 feet. Worth a shot checking just to rule this out .

[jim 56]

thank you had the BC out and it looks like it is good according to the pictures on an earlier forum post.Hoping to finish installation of Crane system today and see if it helps.I read on forum that if when warm and I put finger over filter hole when removed of WRD even though sucking air if idle doesn't change then it should be OK.I will check this today I hope