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-   -   No start on 85 after TB/WP job (https://rennlist.com/forums/928-forum/1147276-no-start-on-85-after-tb-wp-job.html)

Uncle_Rico 06-11-2019 12:53 AM

No start on 85 after TB/WP job
 
I need some help. I have an 85 and I’ve been immersed in the worlds longest timing belt/water pump job. I started the job the day after I bought the car and drove it home. Along the way, I added a pk tensioner, replaced the fuel lines, power steering line, coolant hoses, accessory belts, thermostat, and a lot of other items I noticed that needed to be replaced. I finally got to the point of buttoning everything up and trying to start it for the first time. And the results were not good. The car cranks, turns over and tries to start but then dies. I tried turning it over 7 or 8 times before I started to smell gas so I stopped (the car is in my garage and I’m brutally afraid of catching everything on fire).

Before I start troubleshooting using tips from the billion other no start threads, I wanted to ask a couple of questions.

As I mentioned before, I replaced the fuel lines and have tested them multiple times by jumping the fuel pump. Could testing the lines so much have flooded the engine? If so, what’s the best way to remedy that?

Next question. There’s a major wire hack job on the single blue wire that attaches to the alternator. What’s the function of that wire?

Lastly, back to the fear of fire. I have one chemical extinguisher, but wonder if that would be enough should my engine catch fire in the garage. What’s the consensus here on the best extinguisher(s) to have on hand to quickly put something out?

Thanks in advance for the help. After all the work I put in over the last 8 months, it was really disappointing that it didn’t start. I’m trying to walk my self back off the ledge tonight and not do something I’ll regret like giving up on it.










FredR 06-11-2019 01:32 AM

The blue wire excites the alternator with battery voltage. It also is the source that is used to display the voltage on the dash panel.

For first starts after major maintenance I reckon it is better to have a helper standing by with a hose pipe that is primed and ready to go if needed. Whereas water in the engine bay is not desirable it is better than an out of control fire situation. If the garage is built into your home and you have a wooden home I also recommend trying to start up the car outside- better to burn down the car than both car and home.

Running the fuel pump to test for system integrity is a good move and should not flood the engine unless you have a leaky injector. If you are cranking wit intent to start and the motor does not pick up then it is going to smell of fuel. No point in continuing to crank if the motor is not picking up. Plenty of things that can cause a no start. Obvious things to eliminate are spark leads correctly assigned and all timing marks align correctly. You need to know that the ignition is firing correctly and the CPS is working OK. If you can smell fuel then logic suggests the fuel pump is running and the injectors are firing.

linderpat 06-11-2019 08:03 AM

Also look for loose or disconnected ground wires anywhere around where you did the work. Clean the big ground wire from the lower right side of the block to the engine bay - make sure everything is nice and shiney. Re-check the ground strap in the trunk area too. I have had a few non-starts over the years due to this problem after doing work on the car.

Uncle_Rico 06-11-2019 10:24 AM

Assuming the exciter wire is disconnected or non-functional in its current state, would the car be able to start without it? The engine seems to fire up and tries to run for 2-3 seconds and then just dies.

davek9 06-11-2019 10:39 AM

First good for you tacking a T belt job and getting all back together :)
Now start w/ the basics, you need Fuel in the cylinders and spark and correct timing, right?

You cranked over the engine and smelled fuel, is it raw fuel from a leak, that is the first thing you need to find out and fix.

The engine tried to start, so may have spark but incorrect timing, most (over 80% or greater) get the plug wires on wrong, recheck them, by tracing each one cylinders 1-4 (drivers right) and 5-8 (drivers left).

First thing is to find the source of the Fuel smell, before trying to restart w/ spark!
With the two intake plenums removed, Pressurize the system and look for a leak,
While the Plenums are off, check some spark plugs for wetness.

Let us know what you find or if your stuck.

Dave K

edit that wire is for charging, nothing to do w/ engine running, unless the batt is dead ;)

if you can post o pic of the completed job, we may be able to spot something

Wisconsin Joe 06-11-2019 11:06 AM


Originally Posted by Uncle_Rico (Post 15900160)
Assuming the exciter wire is disconnected or non-functional in its current state, would the car be able to start without it? The engine seems to fire up and tries to run for 2-3 seconds and then just dies.

Yes. If the alternator won't 'excite', it won't generate electricity. That's all.

I'm a big fan of 'basic diagnostics'. However, you say it sputters when you try to start it. That suggests spark (at least some, anyway). You say you can smell fuel. That suggests injector impulse. Those are typically the first things I suggest to check.

From your description, the first thing that comes to mind is spark. It sounds like you are getting some, but not 'all.' I would check wire routing. Its pretty easy to mix up a couple. I'd also check that you have good, solid contact at the coil, distributors and plugs.

Since you are smelling fuel, I'd check the oil. Pull the dipstick and take a good sniff of it. Strong smell of gas? Change the oil. If you are getting fuel into the cylinders, but not firing, it's possible to get that gas past the rings and into the oil. However, unless you cranked it a LOT or have an injector sticking or something, it's not super likely you've put enough gas in the oil to matter. Its not really likely that jumping the pump to test for leaks will put any gas into the crankcase (again, unless there's an injector problem).

One thing to check is to see if it starts on starting fluid. Pull the fuel pump relay and spray a bit into the intake funnels. See what happens. If it does the same stuff (sputters, tries to fire, ect) then you likely don't have an issue with fuel. If it fires up and runs well, then you do (Captain Obvious, at your service :p).

Edit to add:

Clarify the 'smell of gas' please. Is it a strong, sharp smell of raw gas? (like if you took a cup of gas and spilled it) Or is it less? Coming from the engine? Or exhaust?

If it's not firing, and you crank it for a while, the gas that isn't getting burned will come out the exhaust. That's not a huge problem. If you have a leak, it's a problem.

leperboy 06-11-2019 11:24 AM

I've had a no-start after TB jobs. The suggestion on timing is a good one to check. Make sure your plug wires are in the proper order. The one that got me a couple times was vacuum. Make sure all your hoses and your intake runners are all tight and that your MAF is seated snugly. Check that the breather hose going to the driver side of the intake is on and tight. Last one may be checking the timing of your cams again. Is it possible you are 180 degrees out on your cam timing?

Matt

Uncle_Rico 06-11-2019 11:53 AM


Originally Posted by Wisconsin Joe (Post 15900262)
Yes. If the alternator won't 'excite', it won't generate electricity. That's all.

Clarify the 'smell of gas' please. Is it a strong, sharp smell of raw gas? (like if you took a cup of gas and spilled it) Or is it less? Coming from the engine? Or exhaust?

If it's not firing, and you crank it for a while, the gas that isn't getting burned will come out the exhaust. That's not a huge problem. If you have a leak, it's a problem.


I *think* it was coming from the exhaust. The smell was exhaust-ish mixed with gas (hopefully that makes sense and doesn't make me sound too stupid). I could smell it in the car but I had both windows rolled down and the drivers door open. Once my nose got a whiff of a fuel smell my panic reflexes kicked in and I immediately stopped trying to get the engine to start. The smell was not noticeable until at least the 7th or 8th try to get it to start

With the help of neighbors I was able to push the car back in the garage last night and this morning when I left there was no gas smell at all.

soontobered84 06-11-2019 12:16 PM

Wes,
Can you post some pictures of your work? Most interesting would be the harmonic balancer and the front of the engine

Uncle_Rico 06-11-2019 12:38 PM


Originally Posted by soontobered84 (Post 15900446)
Wes,
Can you post some pictures of your work? Most interesting would be the harmonic balancer and the front of the engine

Yes sir. Will do so tonight.

PorKen 06-11-2019 12:59 PM

Charge the battery if you have not done so. 85-86 (with their nascent digital brains) are especially sensitive to battery voltage when starting.

Hold the accelerator pedal to the floor while cranking to clear out the excess fuel.

dr bob 06-11-2019 01:45 PM

Check the coil wires, making sure they are fully seated at both ends. The coil ends are out-of-sight but get a tug when removing the caps out of the way. Verify that you have the firing order correct, correct wires plugged into each distributor cap.

Double-check the cam timing. More than a few first-timers have missed the details of how the crank is set at #1 TDC minus 45º for belt installation on the 32V cars, three cam gear teeth before #1 TDC. Then timing is verified at #1 TDC at crank/balancer and the cam gears.

Look carefully at the harmonic balancer, and verify that the numbers are readable from the front of the engine. The T|0 at TDC has the bottom of the T pointing towards the radiator. More than a few have inadvertently placed the balancer on backwards, causing cam and ignition timing to be wrong.

REMEMBER: --ALWAYS-- place the crank at #1 TDC minus 45º before moving the cams relative to the crank. This position has all 8 pistons below top of stroke, so no risk of valves hitting pistons. If you have to correct a cam timing issue, pull all the plugs so you can rotate the engine easily by hand to get it positioned correctly. There's a chance you can feel if a piston contacts valves if compression resistance is removed.

76FJ55 06-11-2019 02:44 PM


Originally Posted by leperboy (Post 15900311)
Last one may be checking the timing of your cams again. Is it possible you are 180 degrees out on your came timing?Matt

Cam to crank timing is critical, and would be well worth confirming that they are timed correctly and the same on both left and right banks. You, however, do not need to work about being 180 degrees out on cams with a 32V 928 motor. The distributors are directly cam mounted so if you swap the cams 180 the distributor also rotate the same corresponding 180 so the cam timing and ignition position will always remain in sync.

monkez 06-11-2019 04:42 PM

I would also double check for obvious vacuum leak situations. On the '85, it's very easy to have plenum hoses misaligned, an oil breather hose not connected, etc.

Good luck!

Uncle_Rico 06-11-2019 10:30 PM

Quick update. Good news and bad news. The good news is I did have the plug wires in the wrong spot. Specifically 2,3 and 6,7. Yep I’m an idiot.

The bad news is I wasn’t able to test it to see if that was the only problem because my battery is dead (long story). I went ahead and posted some pictures of the engine and harmonic balancer. I’ve yet to put the intake tubes or the top of the fan shroud back on. If there are any other noticeable mistakes, please let me know.

I’ll post an update when I get the battery charged or replaced. I appreciate all the helpful suggestions.

Thanks


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