New to me 74 914 2.0 running on 2 cylinders

[justjoel]

Hey folks, need some help with my '74 914 2.0L I am trying to bring back to life. This car has sat for 15-20 years I'm estimating and has needed a LOT of work. Thankfully I bought this pretty cheap but it is fighting me to come back to life.

I recently swapped to dual Weber 34 ICT carbs because they were cheap and the D-Jet refused to work -- I bought 6 MPSs... none of which held vacuum... and now it’s only firing on cylinders 2 and 4. 1 and 3 have spark, but unplugging the wires does nothing. I also found a bent exhaust pushrod on #1 when changing the pushrod tube seals, and both 1 and 3 had lower compression than 2 and 4 when I tested them.

I’m wondering:

Could a bent pushrod or stuck valve on #1 or #3 cause this?
Could my timing be off and only letting 2/4 run? -- I set TDC as best I could, the mark on the flywheel is pointing to cylinder #1 in the distributor, I could not see the timing marks on the fan though through the peep hole.

Anyone dealt with this issue? I don't think the carb swap has anything to do with it. I think this is either the valve adjustment was 180 degrees out, I have bad mechanical issues or my timing is 180 degrees out? I am not really sure.

Appreciate any advice. Trying to bring this thing back to life. I've already done a lot of work rebuilding the hell hole and installing frame stiffeners to fix the decades of neglect this thing has endured. I just want to drive the damn thing.

[justjoel]

I know 34 ICT carbs will be undersized for this size engine but I got the kit for $100 on FB marketplace just to get it running. Will swap to 40 IDFs later down the road. Surely the 34 ICTs wouldn't contribute to only running on 2 cylinders.... right? That doesn't make sense in my mind. I have NOS pushrods on the way to replace the existing ones. If one is bent there might be more so I'm just going to replace all of them.

[TRP]

Have you done compression test on 1 and 3?
Have you verified that you have fuel going into 1 and 3?

Thanks
Ted

[justjoel]

Ted,

Yes I did compression test and #1 and #3 has compression, they are a little lower than #2 and #4 though. I don't have the numbers with me but I believe they were ~90psi vs 120psi.

I carb swapped it with dual carbs so not sure how fuel wouldn't be going to #1 and #3. I verified they are getting spark and I adjusted the valves as well.

Thanks for responding.

[Rodsrsr]

I would start from scratch and make sure timing and valve lash is correct. Set #1 on TDC compression stroke, both rockers should be slightly loose if correct and rotor should be pointing to #1 cylinder. Adjust both valves on #1 and also #2 Intake and #4 exhaust.

Now rotate the engine to #3 TDC compression (confirm rotor is pointing at #3) and adjust both those valves along with #2 exhaust and #4 intake.

90 psi is low but will still fire, and probably increase if you perform a warm compression check. If its getting spark and fuel to those cylinders they should fire. Also confirm the wires are in the correct order. The firing order is 1-4-3-2 clockwise from number 1 on the distributor. Easy to mix this up and it happened to me when I first got my car running. I went 1-4-3-2 counterclockwise and it only ran on 2 cylinders.

Curious what your symptoms were with the failed MPS. Its unusual for that may to fail. The D-jet can be a little quirky, but most of the issues I've experienced were due to poor connections in the injector harness. When working properly the D-Jet runs flawlessly.

[justjoel]

Thank you for the information. I will verify TDC and firing order tonight. If that checks out I will redo the valve adjustments this weekend. I'm getting project fatigue. This has been months of work.

The MPSs all built vacuum but didn't hold vacuum so they were dead or needing a rebuild. I gave up on the fuel injection and found some used weber carbs on FB for $100. I still have the FI components and can swap it back pretty easily if I ever want to go back.

I hope I have the firing order wrong... that'd be an easy fix. I'll update tonight.
Thank you.

[Brookshire my]

When I first acquired my 914 I had the cylinder numbers mixed up since I was used to working on my 356. They are the same but the engines point in different directions.

[Rodsrsr]

I usually look at the vacuum advance and the angle its mounted sort of points to the firing order direction, and I've used this method my entire life but the 914 is different. The vacuum advance points as though the order should be counter clockwise but its actually clockwise. This is why I originally had the wires crossed, and crossing those two wire effectively kills those 2 cylinders.

[justjoel]

Man I really hope you're right. This project might die if I have to rebuild this engine.
I will surely check tonight. I watched Ian Karr's Youtube video on Porsche 914 for Newbies and he pointed to his dist #1 and I think I have mine set up to be #4 there so I might just be 90 degrees out or have the firing order the wrong way.

Fingers crossed. This is the simplest remedy.

[TRP]

Originally Posted by justjoel

Ted,

Yes I did compression test and #1 and #3 has compression, they are a little lower than #2 and #4 though. I don't have the numbers with me but I believe they were ~90psi vs 120psi.

I carb swapped it with dual carbs so not sure how fuel wouldn't be going to #1 and #3. I verified they are getting spark and I adjusted the valves as well.

Thanks for responding.

If you're only down on those two, and you switched from FI to Carbs - and you tested spark... do you have fuel and compression. It ran before, and you said you did compression tests... so that leaves fuel and timing.

Swapping to dual carbs from FI, you're moving the fuel deliver from at the end of the fuel runner to a carb body... IS that carb body delivering fuel? That's all I was getting at. Pump the throttle a few times while looking down the throat of the carb. Just verify a fuel shot. Pull the plugs on 1 & 3, are they wet? (if they are getting fuel and not firing, the could be wet).

Best of luck! Get that sucker on the road, you deserve it after all the work you've done.

Ted

[justjoel]

Ok,
I checked and double checked TDC but maybe I'm doing this wrong.
I am putting a rod into cylinder #1, watching it go up, lining the mark on the flywheel to the top of the motor, making sure the dist rotor is pointing to the #1 plug wire.

Then the firing order would be (standing on the passenger side and going clockwise) #1, #4, #3, #2

Not sure I understand what I'm missing. The engine fires right up and runs but if I pull the spark plug wires on #1 or #3 or both for that matter, there is no change in the engine performance.

I will recheck my valve clearances this weekend. I recall I had to change the valve clearances quite a bit when I first did the valve checks. I have not removed the distributor since I have owned it, the firing order seemed right when I was first getting it running, I don't recall changing anything when I put new spark plug wires on it.

This is quite frustrating.
Any other ideas would be greatly appreciated.
Thank you.

[justjoel]

You can kind of see the timing marks on the flywheel and dist. location in this image.

[Magyar Kiwi]

Hi
The timing marks are on the outer rim of the fan.
You view the timing marks by removing the black screw in cap in the fan housing, just forward of the oil filler cap.
The cylinder numbers are embossed on the black fan shrouds.
Suggest you invest in a Porsche 914 4-cylinder (1969-1976) Haynes Repair Manual.
Hope this helps.
Cheers

[Rodsrsr]

It sounds like you're doing it right, but you need to make sure its TDC compression not exhaust stroke. You can confirm this by checking the rockers on #1 cylinder when its at TDC. If its on compression stroke, everything will be as you see and both of the rockers will be somewhat moveable because both valves will be closed. If one or both are tight, than they may have been adjusted TDC exhaust which would completely mess everything up. You mentioned that you had to change the valve adjustment quite a bit when you adjusted them and that's a red flag. They should only need minor adjustments. were talking a few thousands. I also don't always trust the flywheel marks because someone else may have marked it for TDC and 180 degrees so its possible a mistake was made. Checking for both valves being loose on TDC #1 is the surefire way. Then check to see what mark is showing on the flywheel for next time.

I would do this to confirm your valve lash is set correctly first. If the valve lash is way off valves may not be opening or closing all the way....no or very low compression.

Once valves are adjusted correctly with good compression and spark, the issue will have to be fuel related.

Don't give up, your close! These cars are super fun to drive once you get them dialed.

[justjoel]

Thanks everyone for the help.
I will be verifying the valve lash tomorrow for sure. Hopefully that is it. I did mark the fan wheel based on the flywheel mark and the dist rotor location and using a timing light cylinder #1 is hitting correctly via the peep hole and fan mark I made. I don't think I'm that far out timing wise but I will verify the valve adjustment and report back. I do have the Hayne's manual as well as Dr. 914's book and I've read through them quite a bit... this one is stumping me though.

Thanks again for everyone's input it's really helping.

[Rodsrsr]

I'm re-reading your initial post and it sure sounds like you may be 180 out, because you mention that you saw a mark on the flywheel (which I can see in the image) but not through the peephole. Someone put that mark there, its not factory.

People often mark the flywheel to make valve adjusting easier when under the car, so that mark may be TDC compression if viewing from the notch underneath, and if that's the case you would be TDC exhaust when viewing from the top. Also you should always see the mark through the peephole. Its a small sideways V on my car.

Did you also confirm no bent pushrods on 3? If the valves were initially adjusted 180 out and you ran the motor, that may be the cause of the bent pushrods.

[TRP]

Did we get an update here? I'm interested to learn what happened.