Wayne, John Walker, anybody, I need some help

springer · 03-14-2003, 06:33 AM

I posted a question on the other forum and it was suggested I ask you guys the question here.

I recently did a rebuild and have been trying to get the thing to run for a while. Needless to say the weather in Minnesota has kept me out of the garage for a few months but now its warming up and I want to get back to it.

Okay so here's the issue... I wasn't getting a spark and didn't realize this right off. In the process I believe I sent so much fuel to the engine that now the cylinders are full of fuel. It's rather cold here still so I think the cold start valve would be sending a lot of fuel (as I understand it). I have so much fuel in it that it is leaking from the cylinders but only when I crank it over sending more fuel.

So I realized that I wasn't getting a spark and checked everything over. What I found is the distributor cap was not latched on the back side and wasn't sitting properly. Fixed that and cranked it over at which point it backfired. It only backfired after repeatedly turning it over.

I am by all means an amateur at this so I may be completely off base, but I think that the timing is set right and that its not starting because there is so much fuel in it that the plugs are soaked and won't fire. I think it is backfiring when one of the plugs does fire lighting a mass amount of fuel causing it to backfire.

Does this sound likely or totally off the wall?

My next step was to pull the plugs, unplug the coil, unplug the fuel pump relay, stick some rags in the plug openings and turn over the engine to get the fuel out. Let it dry out, reassemble and try again.

Let me know what you guys think. Sorry this was a long one.

Thanks

Jim Sims · 10:43 AM

Do not crank over the engine anymore until you take care of a few things. If the engine is that full of gas then it may have washed the assembly lube off the bearings and you could do bearing damage. Here's my suggestions: Pull the spark plugs; discard the plugs and leave the plug holes open so the gas can dry out. Wait a couple of days. Drain the oil (sump and tank) and install a new oil filter. I'd then charge the battery, put a squirt of engine oil in each cylinder, refill the oil tank with oil (9 to 10 quarts), pull the red fuel pump relay (up front in the luggage compartment) and then crank the engine with several 15 second starter bursts until I saw oil pressure. I would then install new plugs and crank the engine with the red fuel pump relay still unplugged and ensure there was spark at the plugs. I would then install the red fuel pump relay, remove the air cleaner and filter and lift up the air metering plate (round disk) until I felt the system stiffen with pressure and the fuel pump whine changes pitch. Then reinstall the air filter and cover and attempt to start car. If it doesn't start with two or three tries then stop and do more trouble shooting; don't just keep cranking. Others may have more and likely better advice. Cheers, Jim

springer · 03-14-2003, 11:32 AM

Jim - sounds like good advice. I'll work toward doing what you've laid out. Thanks

snowman · 03-14-2003, 01:39 PM

Good advice already. The backfire is an indication that the firing order is incorrect and or the timing is way off. Have someone double check you on this before trying to start it again.

A side comment. Why throw away perfactly good plugs? Worst case bake them out in an oven set at about 250 F for an hour and they should be as good as new. If someone dissagrees with this lets start a new thread on the subject.

Jim Sims · 03-14-2003, 02:07 PM

I don't think my wife would let me use her oven to bake gasoline out of spark plugs. I probably wouldn't do it either (kaboom!) although I might use a heat gun on them out on the driveway. I gave up cleaning fouled plugs but perhaps springers are not fouled but merely wet. Then drying out would work, but not in an oven with an ignition source.

Jim

snowman · 03-14-2003, 02:16 PM

Jim,
Do you really think a ceramic plug end, which can only have surface moisture on it as it dosen't really absorb anything would generate enough fumes to burn? Blow the plugs dry and take a propane torch to the end very briefly, I bet it will not even light at all. IF in doubt use the propane torch first, just for one or two seconds, then bake.

I assumed he was using new plugs and they were just wet with gas. I never understood why anyone would throw these out.

Jim Sims · 03-14-2003, 03:45 PM

It's probably not an issue with these plugs but a little gasoline vapor goes a long way. I had a good friend badly burned by igniting gasoline fumes so I'm rather cautious. The cost of a skin graft or even a new oven will pay for a lot of sparkplugs. Cheers, Jim

Dan Owens · 03-14-2003, 05:33 PM

Bob,

Hopefully you'll get more comments that speak to the excess gas issue if the gas quantity is as much as you indicated. I think you may have more than one issue going here too as I mentioned in my other email. The timing may be off but that shouldn't hurt anything until you get it sorted out. I think I'd be chasing the excess gas problem first as that can cause damage. It can wash the lubricant off the cyclinder walls and leak down and saturate the oil which then can cause problems with bearings. I'd pull the plugs and let it air out for a couple days. Then I'd check and drain the oil and filter then refill it. The plugs should still be okay as they shouldn't go bad from being gas soak. Just let them air dry and then clean them and re-gap them. I'd put about an ounce of oil in each cylinder and then disconnect the fuse for the fuel pump and crank in over a few times with no plugs in it to relubricate the cylinders but prevent the fuel from going to the engine. Then it's time to tackle the gas issue. I believe the cold start valve pumps too much gas in the engine if it's not operating properly( I Think) . I'd check into that and see if that is true and find out if you can test that valve. I'd also check the gas pressure and flow and make sure you have proper flow and pressure. Once that's done then move on to the timing. I'd try to manually set or check the timing position, points etc along with the plug wires being in the right firing order. Stick with it buddy and you'll get it sorted out, you've made it this far in the rebuild.

Dan O

Doug Zielke · 03-14-2003, 07:53 PM

Quote:

Originally posted by Jim Sims
The cost of a skin graft or even a new oven will pay for a lot of sparkplugs.

Well spoken. Plugs are cheap.

cstreit · cstreit's Garage

My blow tip on the air compressor seems to work very well... DOn't know that the oven would make me feel "comfortable" either. (That and my wife would have a cow...) I'm already a major suspect after washing my shop rags in the washing machine.

snowman · 03-15-2003, 05:41 PM

Don't you use the dishwasher for car parts too? It works very well. Parts come out clean and, so far, no evidence remains for the wife to find.

Doug Zielke · 03-15-2003, 05:53 PM

Don't do it. My wife most definitely found the "evidence".
(But the dishwasher did do a splendid job of the cam towers.)

Dan Owens · 03-17-2003, 05:28 AM

Guys,

We're getting way off topic from what the problem Bob is having. I'm sure Bob would like to try and focus on solving his issue and not the merits of using a dishwasher to clean your parts.

Dan O

snowman · 03-17-2003, 09:24 PM

You got to clean them somehow.

Wayne 962 · Wayne 962's Garage

Did you get some resolution on this?

-Wayne

springer · 03-26-2003, 08:40 AM

I was out on vacation last week and just got back to this. What I've done so far to no avail...

1. Pulled the plugs
2. Let it air out for the week
3. Drained and changed the oil (which did have some fuel in it)
4. Tried to start... same result, exhaust coming from the tailpipe,
a few pops and then backfire. Seems like it wants to go I just
don't want to keep cranking on it if it backfires.
5. Pulled distributor, rotated crank 180, put distributor in rotor
pointing to #1 wire... resulted in no apparent firing (so I
assumed it was set to #4 not #1)
6. Pulled distributor, rotated crank 180 to set back to what I
assume is #1, again resulted in few pops and backfire

So now I believe I am going to check the individual fuel injector to ensure I am getting an equal amount of fuel to each cylinder as it seems that again cylinder #3 has fuel dripping from it. Does it make sense that fuel would drip out of the head? Seems to me like it should be sealed and fuel should not even potentially leak out.

I was also thinking of running a compression check to see if I have good compression.

I'm getting pretty frustrated with this thing as I've been trying to figure this out for a while. Hate to do it but I feel I'm about at the point where I'm going to send the thing out to have somebody else work on it.

Wayne 962 · Wayne 962's Garage

I would bet $10 that this is a timing problem. Pop the valve cover and use the valves to figure out where TDC is (number one should be closed at TDC). Then check your distributor again. Recheck the wires one more time. I once made this mistake and had the same problem.

The fact that it's popping means that it's trying to fire - which means you have compression somewhere. Double check that the rotor is pointing to the notch in the distributor when the distributor is in the case. It rotates slightly when you install it.

Put a timing light on each of the wires and watch the spark as it cranks. Remove all of the spark plugs but one, and see if the engine is slow when it cranks over that one cylinder. This will check your camshaft timing, and also verify quickly that you have compression.

Sounds like a timing problem to me. Recheck your spark plug wires...

-Wayne

springer · 03-26-2003, 01:26 PM

I'm betting you're right about it being a timing issue. I'll go over the wires again and also ensure I've got the rotor lined up. If that doesn't work I'll move on to the timing light. Can you tell me what you mean when you say the engine will be slow when it cranks over that one cylinder? What would this tell you? I'm thinking it would tell you compression is good on that one cylinder but not positive as to how it varifies camshaft timing. Appreciate the help.

Wayne 962 · Wayne 962's Garage

Sorry, didn't include all the details. Take the rotor off (disconnect the fuel pump relay while doing all of this too). With all spark plugs but one off, then watch the rotor as it cranks, and see if the engine 'slows' down a bit when it comes to the cylinder (I typically use number one) and verify that the rotor is close to TDC as it spins around. You can also do this by hand too - the engine will resist you as you try to crank it on that one cylinder. If your cam timing is messed up, then you won't have compression building up to where the rotor hits the mark on the distributor.

Make sense?

I still think it sounds like an electrical problem. The popping tells me that you have some fuel, some spark, and some compression. Fuel and compression are rarely the problem in a case like this, so the remainder is spark.

Hey, just remembered - the 911SC distributor runs backwards from almost all other 911s. So, if you use a wiring diagram from another car, it won't work properly. The firing order is the same (1-6-2-4-3-5) but the distributor runs *counter-clockwise*. Make sure that this is setup properly, as it will give the exact results that you are getting...

-Wayne

-Wayne

springer · 03-26-2003, 02:06 PM

Wayne, I'm going to check the wires to ensure I have them counter clockwise because I don't think I do.

So as I understand it... #1 Wire will plug in to the plug most closely aligned to the mark on the distributor and then the sequence would be 6-2-4-3-5 counter clockwise from there.

I think that's going to do the trick. I'll let you know.