Author Topic: New Engine Start up - NOT  (Read 622 times)

Tomnistuff

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New Engine Start up - NOT
« on: May 17, 2019, 21:21:46 »
Well, two days ago we got the New Engine Start Up results from Minerva - hook up stuff, crank it, it fires and runs, shut it off - what's next?  I should be so good.  Minerva apparently did everything right.  CONGRATULATIONS!!

Now it's my turn.  I've documented the planning and execution of every step in the reassembly of my car since it arrived back from the Body Restorer in Mid July 2012 on a flat-bed truck sitting on a finger tight suspension.  I rolled it into the garage on the hoist put it on jack stands and removed the suspension so I could start from scratch.

On Friday, May 10, 2019, the car was effectively done except for firing it up.  That action item is number 847 at the top of page 45 of the single-spaced bullet-point document I've entitled Vehicle Reassembly Sequence.  My smile turned upside down.

A couple of days before, I had primed the fuel injection pump and injector lines with shortened plastic pill bottles between the line fittings and the injectors.
Two ten second cranks at full throttle yielded nothing, but the third seven second crank at full throttle yielded one ml of fuel in each bottle.  After cleaning the pill bottles and repositioning them, a 10 second crank at full throttle yielded exactly 3 ml of fuel in each bottle.  The only problem seen was dark fuel in cylinder four output which turned out to be an excess of anti-seize compound on the bubble fitting from the connector nut.  All pump pistons were delivering exactly the same amount of fuel from the lines without injectors.  The injectors had been cleaned and flow tested by Robert Fairchild Industries, so I wasn't going to go to the effort to remove them and flow check them with my crude methods.

So on May 10, 2019, I tried to fire it up.
   First crank at closed throttle for 5 seconds: no firing.
   Second crank at full throttle for 5 seconds: no firing.
   Third crank at full throttle: engine started firing with starter assist but would not sustain.
   Fourth crank at full throttle: engine started running with starter help and ran at below idle speed on two or three cylinders
     at full throttle but died when the throttle was closed after another four or five seconds.

Observations and Conclusions
   Even with the garage door open, it stinks of hydrocarbon emissions (it smells like gasoline burning in an open bucket with
      lots of black smoke)
   Every spark plug is severely carbon fouled. (dry soot not wet fouled - indicates fuel rich environment, presence of spark
      and severely incomplete combustion due to overly rich mixture)
   Exhaust system was also severely carbon coated inside with dry soot. (Suggests fuel burning in the exhaust system but not
      long enough to be noticeable.  I did not check the temperature of the pipes or exhaust manifolds.)
   Every spark plug was warm when I removed it. (so they were firing).
   Engine firing did not respond to throttle plate movement while it was running. (Insensitive to air flow so there was plenty
      at any throttle setting except closed).
   Engine firing did not respond to Injection Pump throttle setting. (so there was adequate fuel, in fact too much, at all throttle
      conditions except closed.

Major conclusion:  Existence of fuel and spark is not the problem, but it is possible that the fuel injection is occurring during the exhaust/intake stroke overlap and burning in the exhaust system ignited and sustained by a slow, poor burning in the exhaust manifolds and exhaust pipes.

Distributor setup is not perfect but is close to correct based on the cam lobes and rotor position relative to the timing marks and pointer.

I will check injection pump timing next, using Joe's IP write-up.

These are my best guesses considering my considerable ignorance of the M-B mechanical fuel injection system.

If anyone recognizes the above symptoms and possible other causal factors, please don't hesitate to comment.

Thanks,

Tom Kizer
Apparently late 1966 230SL 4-spd manual (Italian Version)
Owned since 1987 and wrapping up a full rotisserie restoration/modernization.
Was: Papyrus White 717G with Turquoise MBtex 112 and Kinderseat
Is: Dark Blue 332G with Dark Blue Leather (220, I think)

Minerva

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Re: New Engine Start up - NOT
« Reply #1 on: May 17, 2019, 22:13:27 »
Tom, didn't read all you wrote but had a bit of a head scratcher, mine would fire but not run. Found that there was a 12 volt coil fitted as well as the ballast resistor so getting full 12 volts  at crank and less onve key went back to run position. Worth a look maybe..
Keith

Tomnistuff

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Re: New Engine Start up - NOT
« Reply #2 on: May 18, 2019, 03:04:56 »
Hi Minerva,

I just did a search for the word "ballast" on my Vehicle Reassembly Sequence document and found on line item 563, page 27 that I bypassed the ballast resister but left it installed to make the car look original, even though it has a new Pertronix Ignition with the Pertronix recommended coil.

Thanks for the thought.  I'll check it out.  Tomorrow, I'll recheck the distributor setting (and wiring) accurately, run a compression test, check out the Starting Aid Tour and then start on Joe Alexander's procedure for checking timing on the injection pump without removing it unless it's installed wrong.

I'll keep checking this thread, as I work, to find more ideas and to provide my test results.

Tom Kizer,
Levis, Quebec, Canada
Apparently late 1966 230SL 4-spd manual (Italian Version)
Owned since 1987 and wrapping up a full rotisserie restoration/modernization.
Was: Papyrus White 717G with Turquoise MBtex 112 and Kinderseat
Is: Dark Blue 332G with Dark Blue Leather (220, I think)

andyburns

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Re: New Engine Start up - NOT
« Reply #3 on: May 18, 2019, 06:58:59 »
My money is on ignition timing.  Have you checked with number one at tdc both valves shut and the distributor rotors pointing at the appropriate ignition lead.  Is it possible your distributor cap is 180 out?
Andy Burns, Auckland New Zealand
1963 230sl
1967 250s w108
1969 BMW 2002
2007 Mitsubishi i car

ja17

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Re: New Engine Start up - NOT
« Reply #4 on: May 18, 2019, 07:07:57 »
Good guess Andy, I would go with ignition timing also. Try advancing.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

andyburns

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Re: New Engine Start up - NOT
« Reply #5 on: May 18, 2019, 07:10:29 »
Joe I don't know about you but I always leave the distributor semi loose so I can rotate it while an assistant cranks to get the engine to a point where it runs reasonably.  At that point fine tune with the strobe
Andy Burns, Auckland New Zealand
1963 230sl
1967 250s w108
1969 BMW 2002
2007 Mitsubishi i car

Benz Dr.

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Re: New Engine Start up - NOT
« Reply #6 on: May 18, 2019, 07:21:53 »
Advance distributor timing. It takes more than you might imagine. Even if you can make it start it will stall once it warms up a bit and the IP leans out.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

mbzse

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Re: New Engine Start up - NOT
« Reply #7 on: May 18, 2019, 10:26:23 »
Quote from: andyburns
My money is on ignition timing.../... Is it possible your distributor cap is 180 out?
The distributor dog tooth drive is slighly offset in order to go in one way only. See pic attached.
However, it is possible to mount it 180o off :-\
/Hans S

Tomnistuff

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Re: New Engine Start up - NOT
« Reply #8 on: May 18, 2019, 17:38:27 »
Wow! Thanks for all the replies.  I need to explain the following line in my first post.

"Distributor setup is not perfect but is close to correct based on the cam lobes and rotor position relative to the timing marks and pointer."

The first thing I did when I ran into this problem was to reread about distributor installation and how to verify it.  It has been probably a year since I installed the distributor, 18 years since I retired and 10 years since I setup the two dual point distributors in my '69 V12 Ferrari (gone but not forgotten).  I followed the TM installation instructions when I installed it , but could have made a mistake (wouldn't be the first time).  While turning over the engine to find TDC, power stroke on #1 cylinder, I turned the crank too far.  Instead of going around again twice, I used "Kentucky windage" to estimate where the cam lobes and rotor tip would have been had I stopped turning the crankshaft in time.  It all looked about right but after receiving all the comments about distributor timing (which, by the way, agrees with my initial thoughts), I have decided that the first thing I will do is turn the crank another almost 720 degrees to get to the next #1 power stroke TDC mark and check the distributor again (in other words, do it right this time without guesswork).  Anyway, it is, by far, the easiest next thing to do.  I'm dreading starting to diagnose the Injection Pump installation.
Thanks again for all the insights.
I'll be back with results.

Tom Kizer




Apparently late 1966 230SL 4-spd manual (Italian Version)
Owned since 1987 and wrapping up a full rotisserie restoration/modernization.
Was: Papyrus White 717G with Turquoise MBtex 112 and Kinderseat
Is: Dark Blue 332G with Dark Blue Leather (220, I think)

mrfatboy

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Re: New Engine Start up - NOT
« Reply #9 on: May 18, 2019, 19:14:20 »
Use the toothpick method to diagnose the FIP timing.  Not difficult at all👍
1969 280sl (Aug 1968 build)
Signal Red
4 Speed

Tomnistuff

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Re: New Engine Start up - NOT
« Reply #10 on: May 19, 2019, 03:08:16 »
While I had the spark plugs out and the remote starter hooked up, I decided to remove some doubt and do a cold-dry compression test.  Here are the results:
   #1 :  155 psi
   #2 :  150 psi
   #3 :  155 psi
   #4 :  155 psi
   #5 :  155 psi
   #6 :  160 psi

The following photos show the results of my redo of the distributor installation inspection.  The three photos show:
 o  The current position of the Cylinder #1 cam lobes,
 o  The current position of the crankshaft timing pointer against the timing marks.
         I highlighted them with paint after the Metric Motors Rebuild,
 o  The current position of the distributor rotor relative to the little notch on the edge of the distributor.
         I highlighted the notch on the outside of the distributor with a white arrowhead after the distributor was rebuilt.  I also
         installed Pertronix ignition at the same time.

Tom Kizer

PS:  It looks like the toothpicks can't be avoided.


 
Apparently late 1966 230SL 4-spd manual (Italian Version)
Owned since 1987 and wrapping up a full rotisserie restoration/modernization.
Was: Papyrus White 717G with Turquoise MBtex 112 and Kinderseat
Is: Dark Blue 332G with Dark Blue Leather (220, I think)

ja17

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Re: New Engine Start up - NOT
« Reply #11 on: May 19, 2019, 06:24:01 »
Looks like you have everything indexed correctly Tom.  I am in-line with Andy. I turn the distributor while running until it will idle, then I fine tune with the timing light.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

Pawel Szczesniak

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Re: New Engine Start up - NOT
« Reply #12 on: May 19, 2019, 10:35:35 »
Tom, I am far ahead of the front line of my knowledge and experience here, but still...

I am not sure of the camshaft timing can be verified based on the picture of the cams here. Have you double checked the marks on the camshaft/sprocket? I am not sure if I am making sense here...

I had my FIP out of timing - by 180 degree. The engines runs. It runs worse, uneven on idle, but runs - you can nornally drive etc.
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class

ja17

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Re: New Engine Start up - NOT
« Reply #13 on: May 19, 2019, 15:58:02 »
Pawel is correct, even with the injection timing off 180 degrees, the engine may still idle. May be time to invest $20.00 in a fresh set of spark plugs! Even new ones can get fouled during initial start up.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

Tomnistuff

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Re: New Engine Start up - NOT
« Reply #14 on: May 20, 2019, 03:04:58 »
Hello Gentlemen,

Because today is Sunday, I went to Mass and restricted my day to mental work on the car.

But, I decided to ask one more question before starting to get out my little box of toothpicks for tomorrow.

Q:  Since the issue with my injection pump is, "When I try to start it, which of the two cylinders #1 or #6  is being squirted with fuel during the simultaneous power stroke of cylinder #1 and intake stroke of cylinder #6?"

Given that I know it should be cylinder #6 if the pump is installed correctly, my plan tomorrow is to simply:
    o Unscrew the injection line connectors at #1 and #6 injectors,  I don't want to make a check valve puller or break into the
          pump,
    o Slowly advance the engine to #1 cylinder 20 degrees after TDC on its power stroke,
    o Pull out the coil wire, (actually I'll just leave it as it is.  I never put it back after the previous testing.)
    o Place two of the small pill bottles under the injection line bubble flare fittings and just "bump" the engine about
         180 degrees with my remote starter switch.

All I have to do is check to see which pill bottle has a ml or two of fuel in it, #1 or #6.

If it's #1, the pump is installed wrong.  If it's #6, I can come back into the house, have a beer and start looking for another solution.  That means I'll change the plugs and try to pretend all this crap never happened while I try again to start it for the first time, again while giving it some spark advance.

All that is unless someone else can figure out a better work plan.

Thanks for all the advice so far.

Does anyone think that the above pill bottle plan won't work?

Tom Kizer
Apparently late 1966 230SL 4-spd manual (Italian Version)
Owned since 1987 and wrapping up a full rotisserie restoration/modernization.
Was: Papyrus White 717G with Turquoise MBtex 112 and Kinderseat
Is: Dark Blue 332G with Dark Blue Leather (220, I think)

Pawel Szczesniak

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Re: New Engine Start up - NOT
« Reply #15 on: May 20, 2019, 06:27:46 »
i am still thinking of simple things: have you double checked the leads order in the distributor cap?
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class

450sl

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Re: New Engine Start up - NOT
« Reply #16 on: May 20, 2019, 10:31:19 »
Take measurements only as a guideline , pictures from other poster.

mrfatboy

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Re: New Engine Start up - NOT
« Reply #17 on: May 20, 2019, 14:16:02 »
Lol. I remember taking that picture.

You only need to remove one injection connection to measure and verify correct FIP installation.  Two if you really want to double check yourself. 😀

I recommend removing the furthest front or rear. Which ever is easiest for you.
1969 280sl (Aug 1968 build)
Signal Red
4 Speed

Pawel Szczesniak

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Re: New Engine Start up - NOT
« Reply #18 on: May 20, 2019, 15:35:10 »
Lol or not lol - I suppose hundreds of people are grateful for this picture/procedure as it helped them get out of trouble and save time and money!

Me is one of them... :) :) :)

Just that I had a red toothpick, not blue, first connector from firewall, meaning cylinder 1.
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class

Tomnistuff

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Re: New Engine Start up - NOT
« Reply #19 on: May 20, 2019, 23:14:41 »
Well, I worked on the car a little more today.  I went back to a previous question that was asked and, although the plug wires had been verified, I did it again.  When you are my age, you can remember your first grade best friend's name but you can't remember what you had for breakfast.  I checked that the distributor was wired with the correct firing order (1,5,3,6,2,4) and that from the plug terminals to the inside post on the distributor cap, the total resistance of the wires were each a little above 1,000 ohms.  I'm using NGK BPR6EGP platinum plugs set at 0.035" gap.  Yes, I installed new ones.  NOTE: a couple of posts ago, I listed compression test results.  I forgot to open the throttle during that test but they were good anyway because I had all the plugs out.

Today I put the fuse back in for the fuel pump and cranked the engine until I got fuel out of #6 cylinder injection line.  Then I set the engine at Cylinder #1 TDC before the power stroke and placed a clean pill bottle under the injection line bubble fitting. I then bumped the starter for 1 engine revolution.  I should have gotten fuel in the pill bottle from #6 line during it's intake stroke.  I did the test several times, cleaning the bottle each time to try to understand what was happening.  Sometimes I got fuel from the #6 line, sometimes I didn't.  I concluded that without the injector attached, the fuel in the injection line was probably leaking into the pill bottle at irregular intervals.  Also the quantity of one injection is so small that it's almost impossible to see in the pill bottle.

Theory is great, but practice doesn't always validate it.

I put the system back together with the new plugs and cranked the car again with the remote starter switch.  After a few failed attempts at closed throttle, I cracked the throttle while cranking and it fired and ran at about idle speed.  After warming up for about 30 seconds, I tried to open the throttle, but like before, the engine was completely unresponsive to the throttle and only stalled when I eventually closed the throttle.  I did not vary timing.  I did not have enough hands.  Again, the new plugs were fouled but not as badly as the attempt a few days ago.

Circumstances force me to suspend work on the car for about two weeks in preparation for my brother-in-law's Spring Funeral Ceremony on June 1.  He passed away in February, but Winters in Quebec are so severe that burials are not performed until Springtime when the ground thaws.  This practice is now mostly tradition dating from colonial times.  But outside ceremonies in Quebec during the Winter are miserable affairs.  It can be -30 celsius  There was a funeral service in February, but there will be another on June 1, along with a burial ceremony.  My wife an I are hosting all of the participants for a reception after the Spring ceremony, so I have to organize the house for an undetermined number of people.

In June, I'll get back to the toothpick test.

Do any of you understand why, since this exercise started, the engine has never been responsive to the throttle - at all?  Could it be that there is something in the injection pump that is not responding to the throttle movement?

By the way, this time I checked the exhaust pipe temperature after the period of idle with the cracked throttle.  They were only warm so there had not been any significant exhaust pipe combustion taking place. 

If I think of something easy in the the next couple of weeks and have the time, I'll try it and post results here.

Tom Kizer
Levis, Quebec, Canada
Apparently late 1966 230SL 4-spd manual (Italian Version)
Owned since 1987 and wrapping up a full rotisserie restoration/modernization.
Was: Papyrus White 717G with Turquoise MBtex 112 and Kinderseat
Is: Dark Blue 332G with Dark Blue Leather (220, I think)

Benz Dr.

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Re: New Engine Start up - NOT
« Reply #20 on: May 20, 2019, 23:31:50 »
Why don't you try this:
turn your distributor forward about 10 mm and try starting your engine again. Listen to your exhaust note. If it has a nice ring to it you're probably getting close. If it has some deeper base notes you might want to advance it a bit further.

This is a very quick test. Either you get results or you don't. If you find that your starter sounds like you have a dead battery while cranking your engine over you probably have too much timing in it so you would need to retard timing a bit.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

Tomnistuff

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Re: New Engine Start up - NOT
« Reply #21 on: May 20, 2019, 23:40:07 »
Thanks Dan,
That's an easy one.  I'm still not convinced my pump is installed correctly.  But your judgement regarding spark timing is infinitely better than mine.
I'll post results.
Tom Kizer
Apparently late 1966 230SL 4-spd manual (Italian Version)
Owned since 1987 and wrapping up a full rotisserie restoration/modernization.
Was: Papyrus White 717G with Turquoise MBtex 112 and Kinderseat
Is: Dark Blue 332G with Dark Blue Leather (220, I think)

Benz Dr.

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Re: New Engine Start up - NOT
« Reply #22 on: May 21, 2019, 00:25:30 »
I'm not too keen on messing with injection pumps. You can easily do more harm than good. I'm OK with a couple of external adjustments if you know what you're doing and that's about it.

Turning a distributor? Priceless.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

Tomnistuff

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Re: New Engine Start up - NOT
« Reply #23 on: May 21, 2019, 01:28:55 »
Well Dan, you were right.  It's not great but it's better than a sharp stick in the eye, as my mother used to say.  I advanced the distributor about 10 distributor degrees (turned it counter-clockwise, since it's an 051 for a 230SL.  It sounded better when I cranked it with the remote switch, so I advanced it some more.  After about four tries, during which it tried but failed to start, I advanced it once more, enough that I was worried about rotating the vacuum diaphragm into the plastic fan and had to reposition the vacuum line in its clip and in the injection tube clamp to make it long enough to reach the new distributor position.  I probably should have disconnected the vacuum line.  It wouldn't quite start and run at idle without me touching the I.P. lever just a little, which also opened the throttle plate.  I gave it quite a bit more idle air with the idle air valve, but nothing I did kept it running when I closed the throttle.  At least when I played with the throttle system, it now responds and revs quite well, but I think I advanced it just a little too much because of the required starter effort during crank.

Anyway, I am extremely pleased to go to my less pleasant tasks, knowing that when I start again, I'll have an encouraging place to start.  When it will run on its own, then I can put the timing light on it and start diagnosing instead of guessing.  That will include the toothpick test.

I'll get another new set of plugs or two (I think I've fouled the new ones again), then start through the Technical Manual Tours, including the tours I've already taken.

Thanks a million, Dan.  I was beginning to get depressed and thinking I might miss taking it to Meeting of the Clans II.  Now I'm no longer worried about that.

Tom Kizer
Apparently late 1966 230SL 4-spd manual (Italian Version)
Owned since 1987 and wrapping up a full rotisserie restoration/modernization.
Was: Papyrus White 717G with Turquoise MBtex 112 and Kinderseat
Is: Dark Blue 332G with Dark Blue Leather (220, I think)

Benz Dr.

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Re: New Engine Start up - NOT
« Reply #24 on: May 21, 2019, 01:42:26 »
Oh, you'll get there.

 I forgot to tighten up the clamping screw on a distributor one time and my customer couldn't keep the engine running after it warmed a bit. After a fair bit of head scratching I had him put a vacuum gauge on his engine. When all it showed was about 8 -9 inches I knew that it was late timing. After he advanced the distributor it ran fine.

I was ready to take a 3 hour flight to fix it. ( yes, the doctor did make house calls once in awhile back then ) I believe the shaking of the car hauler made the loose distributor move enough to cause it barely run. Thing is, it ran perfectly when it left so it really threw me a curve. First thing I check now.

Experience  is such a good teacher. ( sigh )
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn