If this post is in the wrong area I do apologize.

The other day we performed a tune up on my car. It has the 5.7 liter 350 CU V8. It ran fine for a week but then it refused to start. I got lucky one afternoon and got it strted but since then no luck. Here is what I have done:

Here is what we added to the engine in the tune up:

New Bosch Platinum plugs
New spark plug wires
Replaced valve cover gaskets
New cap and rotor

Here is what we have replaced since the car will not run:

New battery
New coil
New ignition module
New thermostat

And I am getting ready to install this:

http://www.autozone.com/autozone/cat...dName=Duralast

Any ideas why the car will not start? We have turned the distributor to try to mess with timing but she will not run. She acts like she wants to run and turns over nicely yet she will not start.

Anyone think I have broke valves or the timing chain needs replaced? Or will the part i am putting in do it?

 

If it ran fine for a week then I would not have moved the dist trying to fix it. I hope you have a mark on the original position. My guess is that it's electrical , possible as simple as a bad ground.

 

How do I check or fix that? Find out where the ground comes of the battery and make sure it's OK?

 

Well that is the first thing i would do is make sure that is good but I am thinking that it may be something in the ignition switch ground or reg. ground etc. it turns over ok until it kills the battery? I am not real familiar with the 78 350 Olds so hang in there and some other guys will help out too. you could also post a thread in the tech sections under general or electrical questions and someone will help you.

 

Yeah it will keep turning over until it kills the battery. I'm not sure where to look to see if the ignition ground is OK. Thanks.

 

did you check the carb to make sure it's getting fuel? Pull 1 of the plugs leave the wire on it then turn over to make sure it's getting spark?

 

Yes we pulled the hose from the fuel pump to the carb to check for fuel. She is getting plenty of fuel. We also pulled number one and two spark plugs. She is getting spark. The spark is redish-white though.

 

An engine needs three things to run: spark, fuel, and compression. It sounds like you have spark. You have fuel, but have you checked to make sure it's not flooding?

Going the other way, you pulled off the pump-to-carb line, but have you actually taken off the air cleaner and looked inside the carb to see if fuel is getting in there? Does fuel squirt out of the little jets when you pump the accelerator? Maybe the fuel filter is clogged. (I don't know where the fuel filter is on your car. On mine, it is on the carb, and the pump-to-carb line connects to it.)

If the fuel is OK, do you have compression? It might be a dumb question, but is there a possibility of a blown head gasket? You should get a compression tester and make sure you've got good compression in all cylinders.

 

Right now it will have to sit. As soon as I get some money I'll check out the compression. I haven't checked the jets in the carb. I don't know what to look for. It makes no sense that I can drive it for a week then start it up on a cold Sunday morning and it dies and will not run anymore.

 

Check you spark first. Take one of the plug wire of of a spark plug and stick a philips head screw driver in the socket and hold it abour a 1/4" away from the intake maniflold in a safe location. Have someone crank over the engine and you should see spark jump the gap. If you don't see a spark then check and make sure your getting power to your coil primary. Let us know what you find out. could be a bad coil, even new coils go bad

 

We have already done just that. On more than one cylinder. We get spark. It just isn't the normal color. Instead of a blueish-white spark we are getting a redish-white spark.

I'm almost to tears with this. Thinking about just selling the car to the junkyard.

 

Remove the air cleaner and look down inside the carb while someone pumps the gas pedal. You should see little squirts of gas from the jets with each pump, and you should certainly smell it. Don't worry if you don't know what a jet looks like. If gas is squirting in, it'll be obvious. If you don't see and/or smell gas, then fuel is not getting to the carb. You would then check the fuel filter, or just go ahead and replace it. Why it runs sometimes and not others is a little puzzling. A weak fuel pump, maybe? Another thing to check for (but that also requires equipment you might not have) is fuel pump pressure. But check the carb first. It takes 30 seconds and doesn't cost anything. I still think lack of fuel is the most likely culprit.



I'm not quite sure about this different color spark thing. I've always thought spark is spark. You either see it or you don't. It takes very little energy to ignite gasoline vapor under compression, so if you can see the spark at all, it should be enough.

 

I haven't actually looked but I know after cranking the engine to start for a few minutes you can smell a very strong smell of gas as if it's flooding. I will have to look to see if the jets are working. I really hope I don't need to take the carb apart.

 

Don't install the ignition switch you put in your first post. You need to go about the troubleshooting procedure logically.

I suggest you remove the HEI module from your distributor and take it to the auto parts store to get checked. These will often go out without notice and there isn't any way you can repair it except for replacing it.

BTW, the squirt of fuel you see below the choke plate into the venturi is from the accelorator pump, not the jets. With the carburetor assembled you can't see the primary or secondary jets.

 

If you are talking about this:

http://www.autozone.com/autozone/cat...dName=Duralast

We have already replaced it with a brand new one. Were you talking about some other part?

 

That is what I was talking about. If you've already replaced it and you know for sure it is good then I suggest you make sure you have compression and fuel.

Checking for fuel should be easy. Just remove the fuel line to the carburetor and crank the engine over and let the fuel flow into a coffee can. It should flow out pretty quickly. After a few moments you should have about 1/4 inch of fuel in the bottom of the coffee can. I know this is arbitrary but you will be able to tell if you aren't getting fuel to the carburetor.

To check compression just use a compression tester as the others mentioned.

 

We have already done that as well. As I said we remove the hose going to the carb and the fuel pumped out just fine. I've given up on the car for now.

 

where are you located? maybe right near another member that could come help you check it out.

 

Albany, Oregon.

 

Oh, ok. Well if you have fuel and you know you have spark then you should do a compression test.

BTW, what kind of spark plugs did you put in it? Did you gap them to spec?

 

Did you get the new wires hooked up in the right order? It is different than chevy engines I believe. Try putting the old ones back on to see if you got some bad new ones (Happened to me before).
Since you had added a new coil and ignition module, it might be good to retry the originals.

I suspect ignition - a redish white spark is not healthy. Weak sparks will not even occure under compression. A blue spark is healthy!
My 78 Ford with the Duraspark II system will shoot a blue spark from the coil to the fender - over one inch with a nice audible 'snap'! The HEI on your Olds should do the same or better.

In the process of trying to start it, you probably (accidentally) flooded it also.
Since the car was running shortly before you started all this, I doubt you have compression issues (unless an unusual catastrophic event happened).

 

Still trying to figure out why you have a reddish-white spark unless the gap is not right. It could also be a possability of flooding problem. I would take out the plugs and make sure the gap is right on all of them and I would remove the air cleaner then leave it for a couple of days , gas will evaporate.
Put the plugs back in and try to start again. push the pedal to the floor and turn the key , see if it tries to catch , if so let off the pedal and with luck she will fire up. if not it may be a compression issue. the only way to know that is to do a compression check on the cylinders.

 

Sounds like the timing chain jumped a tooth . Is it a high mile engine? If it turns over faster than normal and almost starts but will not catch, it has the symtoms of a bad gear.Check your timing again....Tedd

 

plastic gear ...

...

pull a plug, put finger in hole , when air pushes your finger out of hole follow that plug wire to the distributor and the rotor should point to that terminal ...

 

It's not a plastic gear. All the timing gears are metal.

Be that as it may the car is running now. All it took was getting rid of the Bosch Platinum plugs I had in there and putting in some AC Delco plugs. Runs just fine. Thanks to everyone that helped.

 

Ah-ha so that reddish - white spark was the problem. AC Delco is the correct plug for mine I think thr R45S.

 

Another bad experience with Bosch parts for my record book...
Glad you got it up and running!

 

Problem solved, great. Have not used bosch plugs in any of my cars. Is this a common problem or just the wrong plug for the car?

 

I think it is just a case of wrong plug for the car. I've had Bosch plugs in my VW for two years and they run great!

 

The problem with the Bosch plugs were that the electrode is very small and once covered in any kind of contaminant that will not fire. The stock plugs have a way bigger electrode.

I still have other issues. I need to flush the radiator soon. I also need to figure out why cylinder one and two have bad compression at low RPM. They work fine at high RPM.

 

How do you know the compression at different RPM's?

 

Because at low RPM taking the spark plug wire off the distributor has no effect on engine RPM as it should. At high RPM when the wire is disconnected the engine shows the normal effect.

 

http://www.hemmings.com/mus/stories/...feature14.html


"About the only weak link in these engines is the timing gear and chain," Duden said. "They came from the factory with the plastic coating and when we replace them we always use steel gears. The other problem is, the saddle that ties two rocker arms together is aluminum and it gets weak and breaks."


I am a fan of "Factory" parts like plugs ...

 

The timing gears were replaced a few years ago with metal ones.

 

I've never heard of removing spark plugs to determine engine compression. The best indicator of compression is to use a compression gauge.

 

X2 on this one , the only way to be sure of compression is to use a guage. it seems strange that a cylinder would have low compression at idle and not at higher RPM. But I am no expert so it would be nice if a couple would chime in on this one.

 

Sounds like to much resistance in the plug wire to me, not the compression

 

I didn't mean to imply we were testing for compression just but removing spark plugs. Sorry.

 

Was that before or after you changed the plugs?

 

Could have told you from experience Bosch plugs aren't worth a hoot in an Oldsmobile engine but I had missed this thread until today.

Any more I'm starting to have my doubts about newer production ACD too, since I put new R46SZ plugs in the wagon and it now gets worse gas mileage and a rougher idle. The ones I took out with 45k miles on them started and ran fine, and delivered around 16 mpg, but I figured they were close to the end of their service life. I'm down to 14 now. I guess I can blame part of it on all gas here is 10% ethanol now, but one would think new sparkers would increase mileage?

BTW I despise ethanol fuel. It's not the savior the guvmint would have you believe it is, but the corn lobby is very powerful in Washten DC.

Do you have any lifter or valvetrain noise at idle? If a lifter isn't pumping up at idle oil pressure, that can cause the same low compression symptom as a weak cylinder. Once oil pressure gets normal, it will function fine.