Fuel, spark, and compression, still won't start

[Danglerb]

Today was "lets get Leo's car started" day, and while we did get some fine explosions, nothing like started occured.

1981 Euro non S automatic (CIS Kjet), sat for years, totally taken apart, fuel tank flushed, timing belt done, and today we tried hard and it didn't go.

Good spark, set to 10 btdc (and moved around some).
Compression measured 140 to 175, except cylinder 5 which was 65 initially and raised to 120 ish with a squirt of oil.

Loosened one of the injector lines and fuel dribbled out, also tried starting fluid in various amounts and locations.

Nothing.

Air pressure could be felt at the exhaust pipe.

Messing with the distributor timing we could get a massive backfire that I "think" was associated with one cylinder (thinking 5 and a leaking valve).

Any suggestions or ideas? Last guess was maybe too much gas, but no strong gas smell was present. Failure to hit even on ether was very disappointing.

Cams maybe 360 crank degrees off?

[785sp]

Come on Dangle, you know by now that it's a timing issue, what with even the ETHER not working!

[MPDano]

Hi 785sp,

DanglerB is right, we tried everything that we (DanglerB, MrGST, RJM65 and myself) could think of. We verified the timing, spun the crank to TDC, both pulley marks right on, pulled #1 plug and piston was on top and rotor pointing to #1 on the cap. We even put a timing light on it while cranking and it was 10btdc. Even after unhooking the fuel pump relay and cranking to rid the fuel of possible flooding, then shooting ether, not even a pop. Anyone got some specific things to try that we may have missed?

[rhjames]

Correct me if I'm wrong, but wasn't this one taken down to the block on both sides, or just one? not that it matters much.....but that #5 isn't good. My first impression is that it's got a bad set of rings (compression number comes up after the squirt of oil).


First, starting fluid (ether) isn't good. Diesel engines in cold weather, fine. Gas engines, you can break something really quick.

I am assuming (very dangerous) the TB job was completed with all timing marks lined up as they should be. Therefore, the cams should be timed correctly. That said, cam timing should not be an issue. They cannot be 360 crank out--maybe 180, but I digress.

I further doubt you have a cam timing issue due to the compression numbers listed.....

You note a backfire issue.

Check the distributor timing.

Old school way to set timing is to remove the #1 spark plug, put you finger over the plug hole, bump the engine until the pressure blows your finger off the hole, and then see where the distributor rotor is pointing. Then align the #1 plug cable to the rotor. Make sure the firing order of the spark plug cables (on the distributor cap) are correct. It should start, and you can fine tune timing after it's running.

I do this on every engine I work on, because I'm old and I don't trust timing lights or balancer markings.


As to the fuel issue---

Mike, you know the drill on CIS.

CIS test gauges (don't you have a set....?) will give you an idea if the WUR or distributor or any other related parts are functioning properly.

If the WUR or distributor isn't functioning properly, it's a PITA to get it running right.

Questions:

Were the fuel pump, filter, accumulator, and all fuel lines, completely flushed or replaced? (If the engine doesn't get any fuel delivered, it ain't going to run....) Just because you hear the fuel pump running, doesn't mean there isn't a problem downstream......Start from the tank and work forward.

What condition are the injectors? Same old crap that's been in there for thirty years? Or newly cleaned....? or totally new? Even with junk injectors, it should start and run if every thing else checks out OK......


We had these same issues with Dad's 79 (when we first got it), except for the backfire issue. I poured a little gas in the intake, it would start and run that gas out, but would not continue to run. It then received a new fuel pump/relay, WUR, fuel distributor, and 4 injectors. Then it ran like a scalded dog until this past month when the TB let go......


All of this said, I believe you possibly have two issues---proper ignition timing (including firing order) and fuel delivery.

Let us know---




My name is spelled correctly here>>>>>>>>>Russ

[MPDano]

Hi Russ,

Correct me if I'm wrong, but wasn't this one taken down to the block on both sides, or just one? not that it matters much.....but that #5 isn't good. My first impression is that it's got a bad set of rings (compression number comes up after the squirt of oil).

Nah, I gave up on that idea. I ended up buying a used motor from a local Porsche dismantler. No records on the engine, but it was clean and looks like recent work on it. Valves looked brand new from looking down intake hole, Plugs were perfect light brownish, and there was a lot of new gaskets all around the engine. It was a newer US engine (82 I think) and had electrical injection. I removed this and put my CIS stuff on it.

Check the distributor timing.

Old school way to set timing is to remove the #1 spark plug, put you finger over the plug hole, bump the engine until the pressure blows your finger off the hole, and then see where the distributor rotor is pointing. Then align the #1 plug cable to the rotor. Make sure the firing order of the spark plug cables (on the distributor cap) are correct. It should start, and you can fine tune timing after it's running.

I do this on every engine I work on, because I'm old and I don't trust timing lights or balancer markings.

I like this, I may try this when I get a chance. Wires verified to be correct from cap to plug. Battery charger is on it now.

Were the fuel pump, filter, accumulator, and all fuel lines, completely flushed or replaced? (If the engine doesn't get any fuel delivered, it ain't going to run....) Just because you hear the fuel pump running, doesn't mean there isn't a problem downstream......Start from the tank and work forward.

Used fuel pump form 928 Intl, new fuel filter, whats an accumulator? All fuel lines and tank were flushed, replaced rubber lines as needed.

What condition are the injectors? Same old crap that's been in there for thirty years? Or newly cleaned....? or totally new? Even with junk injectors, it should start and run if every thing else checks out OK......

Injectors were good to my knowledge <-- not saying much. I did have to replace 2 of the 8. I soaked them in carb cleaner and with a little bit in the injector, used a compressor to blow them out. All had a great spray pattern.

If the WUR or distributor isn't functioning properly, it's a PITA to get it running right.

I know that distributor seems to function as I pulled the lines on each one while cranking and fuel comes out. Not sure about the WUR or where it's located.

How much fuel did you pour down the plate?

[Danglerb]

Not one hit during all the cranking.

I have a top quality fuel pressure test set from Harbor Freight, but it doesn't include the adapters for CIS. I'm thinking we need something like a T to fit inline to each injector, should also work on the WUR in and out, and some kind of banjo fitting adapter.

Given the hole the plugs go down in, maybe use the compression gauge instead of a thumb.

[785sp]

One more idea:

My distributor was reinstalled incorrectly at some point so that my firing order is all shifted by one. I've left it that way (because it runs fine and I have a tendency to break things that I try to correct), but there's a chance this could be your problem. If you put your original or a new distributor cap on your used engine and the used-engine distributor was off, or if you put the distributor back in yourself and didn't set it right, or if your distributor is set right but your distributor cap is off by one, these could all cause the same problem of the spark not coordinating with the fuel.

A further possibility is that the air flap in the CIS "neck" (which is connected to a lever, etc.) is somehow jammed so that even the ether is not actually getting to the cylinders.

[Danglerb]

Originally Posted by 785sp

One more idea:

My distributor was reinstalled incorrectly at some point so that my firing order is all shifted by one. I've left it that way (because it runs fine and I have a tendency to break things that I try to correct), but there's a chance this could be your problem. If you put your original or a new distributor cap on your used engine and the used-engine distributor was off, or if you put the distributor back in yourself and didn't set it right, or if your distributor is set right but your distributor cap is off by one, these could all cause the same problem of the spark not coordinating with the fuel.

A further possibility is that the air flap in the CIS "neck" (which is connected to a lever, etc.) is somehow jammed so that even the ether is not actually getting to the cylinders.

Leo pulled the distributor cap and bolt and we set the rotor to #1 at TDC.

I used a Porsche approved hood support device (broom handle) and pushed the meter plate down in a couple of the various trys. We also shot some ether in via the transmission vacuum line that goes in the front of the intake body, and another time into the line from the AC aux air input valve.

I don't understand how it was, but strongly suspect the spark and compression timing are off.

[MPDano]

Yeah, there must be a different (Porsche) way to check timing because the normal way isn't working correct. Hey DanglerB, did you lok at that S4 while you were out here? I forgot about that and wanted to check it out with you, I might be able to take a look at it for you and take some real pics. It's Wild Animal Park with my 14 month today

[MPDano]

Ok, for the hell of it before we leave. I went and put a little bit of gas down the meter and with a fully charged battery. Cranked her over, just pops once in awhile. This has to be timing but stumped on why we can't get it right.

[rhjames]

OK--different motor.



timing still may be an issue, but lets look at fuel.

I have poured a handful of gas (not a coffee can full) into the intake (at the distributor flapper) and engines have fired up. This was after verifying timing was correct (see my above post), and compression was OK. (if you compression timing was off--ie: cam timing--you would not get the compression numbers you got)

Leave the ether for your diesel-----

So....Remove the air cleaner totally (you probably already have) and just use a handful size amount of gas. You can always add more.

make sure the flapper is move-able--not stuck as 785 has experienced. Do not move flapper while trying to start--it is very sensitive and will not let the engine start if you open it too far. Use your finger, not a broom handle----it won't bite you----and be gentle.

Re-verify distributor, spark plug cable position, firing order, etc....

Re-verify each spark plug is firing (remove plug, attach to cable, turn over engine while ground electrode is grounded to the block/head).....Is the plug arcing? Do you see a spark?---Check all eight of them.



That thing ought to fire up, and at least burn the handful of gas.

When it does, you can then move on to fuel delivery issues or CIS issues.


you guys are on the right track---





My name is spelled correctly here>>>>>>>>Russ

[Danglerb]

First thing, verify the compression stroke on cylinder #1 vs distributor rotor position.

[Landseer]

Right, Dangler.

We need MP Dano running! He has worked EXTREMELY hard to resurect this beast.

A little oil in a cylinder to start with, after long downtime, is perfectly fine.

Post some pics, lets go step by step and get her going! Keep the faith. It WILL run.

[MPDano]

Thanks Lanseer. Pretty frustrating when we, DanglerB, MrGST and RJM65 were at my house all day Saturday and no go. Also, my neighbor joined in the brainstorming. We are all stumped!

[Dean_Fuller]

How about pulling a spark plug right after trying to start...see if it smells of fuel. I'm wondering if there was a cross up changing the CIS over from old motor to new.

[MPDano]

Hi Dean,

Yes, we verified fuel to all plugs.

[devilinblack]

Just from my limited experience, my money is on the timing being 180 degrees off.

[MPDano]

If I did this, then would my compression be the same? This was one of the discussions on Saturday. I am getting normal compression now (except 1 low) around 165 average on the other 7.

[devilinblack]

Honestly, I don't see any way that compression would be affected by the distributor being 180 degrees off.

I suppose another way to test for TDC on the compression stroke would be to put your compression gauge on cylinder 1 and hand crank the engine until you see compression go up and your timing mark is at TDC. This would be doing the same thing as covering the plug hole with your thumb and waiting for it to be blown off on the compression stroke. This method may not work as I've never seen it referenced on line but I've seen the thumb thing mentioned in a few places when I was trying to get my distributor lined up correctly after removing it to pull some other parts off of the engine.

Once I got around to hand cranking to TDC I realized I was one tooth off on the distributor, but mine would still fire and run (badly). 180 degrees off, I can't imagine that it would fire or run because at TDC when the plug fires the exhaust valve is open and your fuel air mixture is no longer compressed or in the chamber, correct?

[Danglerb]

He means 180 distributor degrees, that the cylinder is firing on the exhaust stroke instead of the compression stroke.

Put the compression gauge on #1, turn the motor over by hand until you see pressure. That should get you close, but I am not sure how best to get TDC, but it might be close enough to check the rotor.