Newly rebuilt engine starts but won't run? - FIXED, NOW RUNS

[riddleyo]

Hello,

I put a new cylinder head on my 1985 VW Golf - 1.6 N/A Diesel. I have everything put together. I used a mighty vac on the return line of the injector pump to draw in diesel fuel through the system. I cracked the injector lines and started the car and watched fuel bubble out of each injector. I tightened the lines and started the car. The car starts and runs but as soon as I let off the key from starting it, the car dies.

I am pretty sure it has something to do with the wiring. I have the stop solenoid wired to the original harness connector. I have a big black wire that isn't on any lug because I have no idea where it goes. My glow plugs also don't work, so I jumped a wire from the bus to the battery for 7 seconds before I start it. Also, my coolant and oil lights blink when the key is in. So thats why I think it is my wiring, I will post pictures of my wiring situation ASAP.

Does anybody know why the car will start but die as soon as I let go of the key? How can I jump my stop solenoid to prevent it from stopping the fuel if that is the problem!? I'm so close to getting this thing to run!

[DCC]

Plug a cable from the stop solenoid directly to the battery +. Start engine. To stop it, simply unplug that cable from the baterry and it will stop the engine. This is a good test to know if the solenoid is working or not.

Anyway, you can unbolt the solenoid, remove the inside blac plastic cap (that tiny thing does the work, comes out pulling) and the spring, then bolt back to the pump. That way you'll have to stall the engine to stop it, though.  :wink:

[jtanguay]

Plug a cable from the stop solenoid directly to the battery +. Start engine. To stop it, simply unplug that cable from the baterry and it will stop the engine. This is a good test to know if the solenoid is working or not.

Anyway, you can unbolt the solenoid, remove the inside blac plastic cap (that tiny thing does the work, comes out pulling) and the spring, then bolt back to the pump. That way you'll have to stall the engine to stop it, though.  :wink:

but look on the bright side... if your alternator/battery dies, the engine will still run  :lol:

[Vincent Waldon]

If you have a test light or multimeter the scientific way is to remove the wire you have running to the IP fuel cutoff solenoid and confirm that it gets power when the key is in the "run" position and "start" position.

It kinda sounds like whatever wire is being used only has power in the "start" position ?

[riddleyo]

I had my dad hold a cable from the battery to the solenoid while I started it. It fired up and it sounded like it reved up but died instantly. Behind the car there was a lot of white smoke.

Maybe it isn't wiring now? I have 1.6TD 155 bar injectors with merc nozzles on my N/A. Could that be a reason? I'm not sure if I should advance it or retard it. I had it timed to 1.05mm, but retarded it a bit when I couldn't get it to start yesterday because I didn't have the glowplugs on. Now that I have the glowplugs on, should I advance it? I also put on a 3 notch head gasket, maybe there is no compression? Does the large amount of white smoke mean too advanced or too retarded? Should I try using the cold start cable to start it; it is about 65 degrees fahrenheit outside right now.

I don't have a clue where to start.
Thanks

[Vincent Waldon]

EDIT:  entire post deleted as the rantings of a sleep-deprived idiot... of course increasing the injector breaking pressure retards the timing.

[riddleyo]

The 155 bar nozzles have substantially advanced your timing (NAs are timed assuming 130 bar nozzles) and 1.05 is substantially advanced beyond the 0.95ish the NA engine is normally timed at.

White smoke can also a sign of advanced timing.

I'd suggest substantially retarding your pump timing... 0.90mm perhaps since you have 155 injectors... and then see if it will start.

Three notch gasket won't cause your car not to start, nor will not using the advance mechanism, assuming the car is not in the frozen north !!

Okay, I will try that first thing when I wake up tomorrow morning.

But I had a question, shouldn't 155 bar injectors retard my timing? My thought was that it takes longer for the injector pump to compress the fuel up to 155 bar versus 130 bar. This means it retards the timing slightly. So my thought was to advance the timing to 1.6TD levels (~1.05mm) to compensate for the injectors in my N/A.

But I will try retarding the timing to .90mm and try starting it. BTW, your timing guide on your site is VERY helpful with the pictures and all.

Thanks

[jtanguay]

running a can of diesel purge might help free up stuck vanes.  worth a shot vs a rebuild.

i'm going to go off on a limb here, but maybe you should try increasing the idle and possibly the residual fuel screw?  to verify if this theory is correct try giving it some diesel while starting it.  if she holds then it is just an idle issue.

[jimfoo]

You could also try installing a low pressure lift pump before the IP.

[Vincent Waldon]

Dudes... my apologies for my earlier post.. the OP is on the right track to use TD timing specs if using TD breaking pressure spec injectors.

My bad...  :oops:

[riddleyo]

Well I bought a compression tester and a viton injection pump reseal kit...

First, I'm planning on rebuilding the injection pump. Then I'm going to check the compression and start the thing. "Pimping out my glowplugs" will be in order also.

Pics and results will be up soon....

[myke_w]

I would suggest running a low pressure pump before you go through all the trouble of a rebuild.  The white smoke everywhere could point to a timing issue. Also, IIRC, early NA cars were supposed to be timed in the 80 - 85 range.  And, just to be sure, the IP gear had the mark at 12:00 when you timed it right? It's not hard to get them 180 degrees off..

The electric lift pumps are cheap and you can surely use it again for something else

*compression check as libby notes is also a great idea

[riddleyo]

Hello everybody.

My compression checker hasn't arrived yet, so I just took the damn injection pump apart already. I got all the way to the feed pump, and guess what? The vanes moved freely! So there goes that idea. I was really hoping the vanes would be rusted shut, unstick them, problem solved. Oh well, I have a viton reseal kit in my hands now, so I plan on replacing all of the seals. Here are some pics:



As you can see, the vanes looks great. There is some rust on the feed pump surfaces, but it doesn't look like it would prevent the car from starting. I plan on taking some 1000 grit or something and getting rid of the scratches and rust, but I doubt that will fix my starting problem.

Myke W: Yes, the line on the IP gear pointed up and the key on the IP pointed to about 10'oclock.

jimfoo: I was looking into the solid state lift pumps, I might install one after I know this thing runs. These cars didn't come with the lift pumps originally so I shouldn't need one to get it started at the moment.

So what else could it be? I REALLY hope it isn't low compression because then I have to rebuild the whole ***ing engine!!! I've already rebuilt the cylinder head and up, I really don't want to take that damn thing off again.    :evil:  :evil:  :evil:  :evil:  :evil:

[riddleyo]

Well, sorry to hear that you dug that deep and didn't find the solution.  FWIW, the vanes usually stick from the fuel drying up and leaving a residue and not necessarily from rust.  Rust would be worst case scenario.  

What is the history behind the car?  What was the incentive behind rebuilding the head?  Was it running prior to that?

Andrew

History: Saw an ad in craigslist for a VW Diesel for $400. I drove over and looked at the car. The floorpans didn't look too rusty but the previous owner said a mechanic looked at the engine and it needed a new cylinder head. I bought it because I wanted to learn how a diesel engine works and I like working on cars.

Rebuilding the head: The old head had the solid lifters stuck inside their bores, so I bought another cylinder head and rebuilt the entire thing with new valve stem seals and new valve seats. I ported and polished the cylinder head put it all back together. Then I clearanced all the valves with new valve shims.

Running prior: Nope, never have seen it run. It starts, fires, and revs up but as soon as a release the starter it dies immediately.

Hopefully my compression checker will arrive here tomorrow.

[Quantum TD]

I seriously doubt that the problem keeping it from running is compression related.  

When you get it back together you should try running it from a separate container of fuel.  Andrew

Indeed. If I were you, I'd try firing it up with a squirt bottle full of CLEAN diesel fuel. Hook it up straight to the pump and see what happens. Be sure to prime your pump by using the same quirt bottle to fill the IP through the OUT hole (return hole). If that solves the problem, I'd change the fuel filter and blow the lines back to the tank. Inside the tank, there is a little screen on the sending unit where the fuel is sucked up from. It might be clogged.

Just a quick question though: Are the Merc nozzles new or used? Generally speaking, the old injectors should have been good enough to at least get the car running. After that, you can worry about performance/fuel economy. The old injectors may have crap spray patterns and off breaking pressure, but they almost always 'work'. If you have the old ones laying around, you might try them along with the squirt bottle trick.

I just worked on a 1984 Rabbit that sat for some time (about 10 years). I got it started with the squirt primer trick, but once I hooked the pump up to the tank with some fresh fuel, it died. The pump was sucking air in thru the input shaft seal. So, it may turn out that after you put your pump back together, it will fire up fine.