Won’t start, cylinders flooding

[FirstDotLast]

[908/930]

Just checking one thing, are you sure you were on compression stroke at Z1 when installing ignition distributor? I did not think an engine could run 180 deg out but have seen it when a marine tec who was working on a boat engine left the country prior to finishing( chased by authorities). He could not get it to run after a rebuild and I was suckered in to get it running. Pull a injector and check if it is leaking with just ignition on.

[mark houghton]

So I took the time to re-read all your posts. More and more points to a problem with the fuel distributor, gas leaking past the control rods and into the ports when it shouldn't be, independent of the position of the metering arm. Maybe a worse case scenario but seems you almost ruled out everything else.
What we know is this: system and control pressures are good, air plate appears properly adjusted, CSV valve taken out of the equation, yet still gas flows through the injectors without the engine running...and even when running its way too much and you're unable to lean it out.
Ugghh...looking to the brain trust on here to jump in.

[FirstDotLast]

Originally Posted by 908/930

Just checking one thing, are you sure you were on compression stroke at Z1 when installing ignition distributor? I did not think an engine could run 180 deg out but have seen it when a marine tec who was working on a boat engine left the country prior to finishing( chased by authorities). He could not get it to run after a rebuild and I was suckered in to get it running. Pull a injector and check if it is leaking with just ignition on.

It seems like there would be much bigger problems if I was 180deg off but also I didn’t remove the distributor other than the cap which was definitely put on correctly because I marked it before taking it off. Also like I said, when I turn the car off and it burns the leftover gas it seems to run correctly for about a second. Which is really telling me it’s a “too much fuel”/mixture issue.

[mark houghton]

Originally Posted by 908/930

Just checking one thing, are you sure you were on compression stroke at Z1 when installing ignition distributor? I did not think an engine could run 180 deg out but have seen it when a marine tec who was working on a boat engine left the country prior to finishing( chased by authorities). He could not get it to run after a rebuild and I was suckered in to get it running. Pull a injector and check if it is leaking with just ignition on.

Good points, let's not overlook the obvious, that could cause a lot of unburnt fuel. But I still keep coming back to the fact that his injectors are squirting with just the pumps running. His 10 minute pumps running just to warm up the WUR for control pressure testing filled his cylinders.

[Alan L]

So now things get murky. Your pressures are good.
Yes, there is a possibility something is wrong in the fuel head (FD). A damaged O ring around a metering slit (or two) would give you what you saw on 2 cylinders.
Turning in to a head scratcher. Sooooo, what I would do next is pull all injectors (you have to break the fuel line on them first), then hook them up and place small jars under them, and run the pumps for 15 sec. Are 2 cylinders out of whack with the rest - like badly? If so, the answer is in the FD.
Are your pumps running with just Key On?
Alan
Edit, 45 sec may be a better injector test time - at idle flow settings. I am used to WOT or near to, and 15 sec is plenty of fuel (50-75 cc)

[908/930]

You said cylinders 1 and 5 had lots of fuel delivered, you could start with pulling those two injectors out and check for leaking. I don't think you can trust you AFR gauge at this point, those work well when hot and engine running close to normal.

Edit, If you removed your spark plug wires from the cap double check they are correct.

[FirstDotLast]

Before I test the injectors, I pulled the fuel head to clean it out. It’s actually in decent shape inside and the slit o-rings look okay and piston moves pretty smoothly with the spring in there. That being said, the diaphragm is pretty beat up. (Check picture of Swiss cheese) Could this be caused by a bad diaphragm leaking fuel to the injectors? I guess I would have expected the pressure to be all off in that case. I know there’s no official rebuild kit for these things but I have an ultrasonic and I cleaned the head. Need to figure out what to do about a replacement diaphragm.

If I’m on the wrong track, I’ll put it all back together and pull and test the injectors. Not looking forward to the intercooler side ones haha

[FirstDotLast]

Originally Posted by 908/930

You said cylinders 1 and 5 had lots of fuel delivered, you could start with pulling those two injectors out and check for leaking. I don't think you can trust you AFR gauge at this point, those work well when hot and engine running close to normal.

Edit, If you removed your spark plug wires from the cap double check they are correct.

Yup, double checked the wires and they look right too. I’m getting to pulling the injectors at this point

[Veeveessees]

Nice.Thanak you for this info.

[Alan L]

That diaphragm does look beat up. It may have been better to check the injector end first.
There are rebuild kits - BTDT.
Have to go by memory - not at home right now. Google Salvox. UK I think.
You will be doing a recalibration of all injectors now anyway.
Alan

[mark houghton]

Gotta hand it to you man, more enthusiasm than I have to pull that off and take a peak.
I need to remove the entire top, not just the head, to address plate height adjustments. Reaching back behind in the dark by feel to the spring loaded screws challenges my poor aging body.

[FirstDotLast]

Originally Posted by mark houghton

Gotta hand it to you man, more enthusiasm than I have to pull that off and take a peak.
I need to remove the entire top, not just the head, to address plate height adjustments. Reaching back behind in the dark by feel to the spring loaded screws challenges my poor aging body.

Hmm can’t you just remove the three nuts holding the bottom of the mixture assembly to the motor and take the whole thing out? Then you can remove those spring loaded screws and adjust it on a bench. I’m getting off topic here though. I think I’ll have the FD rebuilt and flow tested along with my injectors. Just to be totally sure there’s no issues there.

[mark houghton]

Originally Posted by FirstDotLast

Hmm can’t you just remove the three nuts holding the bottom of the mixture assembly to the motor and take the whole thing out? Then you can remove those spring loaded screws and adjust it on a bench. I’m getting off topic here though. I think I’ll have the FD rebuilt and flow tested along with my injectors. Just to be totally sure there’s no issues there.

Not clearance to do that without engine out (I don't think so anyway), which I really don't relish doing.
Right decision to send the whole thing in for a rebuld.

[908/930]

Do you think the injectors are original? If so just order new ones.

[FirstDotLast]

Originally Posted by 908/930

Do you think the injectors are original? If so just order new ones.

My injectors are almost definitely original, the car is low mileage but since the entire rest of the fuel system is new at this point I suppose I might as well to eliminate any other variables.

[FirstDotLast]

Originally Posted by Alan L

That diaphragm does look beat up. It may have been better to check the injector end first.
There are rebuild kits - BTDT.
Have to go by memory - not at home right now. Google Salvox. UK I think.
You will be doing a recalibration of all injectors now anyway.
Alan

Thank you! Looks like salvox would have the kit I need. Yes getting it all recalibrated and flow tested is the annoying part. Might just send it all out at that point to be done professionally, then put it in the car and give it another shot.

[Alan L]

Can you sort Mark's airplate out while you are in there? He is getting the stutters.
Alan

[Tinker]

Wow. You're digging into it now. I think the best course would have been to pull the injectors to check for some leakers.
I'm getting mine running after sitting for 10+ years. Pulled and cleaned the tank, replaced fuel lines, took apart the WUR, pulled the injectors. You can test the injectors with compressed air. The spec is betwwen 2.1 to 3.2 psi. Mine look original and all where within spec so I held them injectors open with a piece of wire and back flushed them. Only got a small amount of crude. Spray patterns looked fine.
Mine still has an occasional slightly miss at idle so I'm running a few doses of Techron and Mystery oil and if it continues, I'll pull the fuel head to inspect and rebuild.

Good luck.

Tinker

[FirstDotLast]

I did end up getting new injectors just to eliminate it as a variable and luckily the injectors for the ‘86 US engine are much cheaper. Waiting on fuel head to come back and will update when I get it.

Yup, have to dig in head first. I’ve had the car for about 15 years and have seen this forum go from very active to just a handful of really knowledgeable people left who still love working on these. Unfortunately many of the 930s in the world that were around back then have ended up in collector garages, scrapped, or forgotten so happy to do what I can to keep it going. Plus my wife tells me I always have to have a project to do haha. If it wasn’t this car it would be a different one.