TheSamba.com :: View topic - 1978 Bus- started briefly but won't start again

Thu Oct 14, 2021 11:05 am

We inherited a 1978 vw bus from my wife's parents (she was born in it in 1985, an interesting story). It has been sitting for approximately 25 years.

I cleaned out the fuel lines by syphoning them, replaced the fuel lines, changed the oil.

I got it to start for about 1 minute and then it stopped again and I couldn't get it to start again.

So then I, changed the spark plugs and spark plug wires, replaced ignition coil and swapped out the points and condenser for an electronic ignition. it's a bosch 009 distributor btw.

I still can't get it to start. I can verify power to the coil, but when I try to pull out the cable from the distributor to the coil and check for spark at the coil, i don't seem to find any.

Any suggestions would be appreciated on where to go from here.

I have never worked on cars before, but I have done these steps and am trying to follow the how to keep your vw alive for compleat idiots.

Thanks

Thu Oct 14, 2021 12:09 pm

Is it fuel injected or carb? That is key info anyone will need.
FI needs a decent charge on the battery to fire.
If FI, from your description it sounds like the cold start valve gave it an initial dose of fuel, and perhaps the fuel pump is not coming on.
If it's been converted to a carb or two, seems like no fuel getting fed in after using up what was in the carb.

Now with replacement bits in it, you need to get spark at the right time and fuel. Back to the first sentence.

Thu Oct 14, 2021 12:22 pm

Ya, we need to know what you're working with exactly - old Buses have weird things happen to them over the years. Can you post a photo of your engine compartment?

Thu Oct 14, 2021 12:37 pm

If it's original, one notion -- sometimes fuel injectors need a good whack to free themselves. I remember diagnosing 2 "no-start" situations on JDM motor swaps to this......... you can remove the injectors and soak them, if you like pain. Or you can just whack them without breaking them and hope for the best :)
I'm not saying that is the issue, but it's one thing that isn't uncommon with fuel injection motors that don't start when they should, after sitting 10 years. It would make sense with the cold start valve theory above (which is a very logical one).

However, the Bosch 009 is an indicator that someone has futzed with the bus. Please do post some engine bay pics, if you can....

I'm assuming that we might see a center mounted carburetor.

Thu Oct 14, 2021 12:37 pm

My inlaws were in the airforce and had the bus shipped to turkey in the 1980s where apparently the FI was swapped out for a single weber progressive 32/36 carburetor.

Update: I was able to verify spark at the coil. I am assuming the next step would be to check at the plugs and then it would be the carburetor.

If I have spark is there a way to test the carburetor without rebuilding the whole thing? I will say that I did manually pump the accelerator pump. I was told that this might help get fuel to the float bowl, but fuel started spraying out of it. I am not sure what this means.

Thu Oct 14, 2021 12:40 pm

Did you try manually dribbling a little gas into the carburetor? :)

Or... starting fluid... or WD-40.... and/or "carefully" administering a jolting whack to the carb with a hammer to free any stuck floats etc

Another odd trick, putting a latex glove on, spraying a bunch of carb cleaner everywhere in the carb, then opening the throttle fully, and having someone crank the motor a couple times while you seal the top of the carb with your hand (using the glove), to make the carb vacuum itself out..

Obviously, the right way to deal with a problematic carb is to take it off and clean it/ rebuild it.

Thu Oct 14, 2021 12:43 pm

If the bowl is full you know you're getting fuel TO the carb. If you have spark and it's still not starting the carb is suspect.

Has the distributor moved at all? Timing somewhat close?

Agree with above - dribble some gas in the carb throat (or use a quick spray of starter fluid). See if it fires or sputters.

Thu Oct 14, 2021 1:54 pm

First verify spark at the spark plug before messing with the fuel system.

Once you know you have spark, properly timed and sequenced (wires correct on cap?), only then move on to fuel.

Do we know your fuel pump is sending gas to the carb?
Webers lack a choke, right? If spark is 100% good then it may just not be rich enough to start without a bit of extra fuel.

Thu Oct 14, 2021 1:56 pm

jfeades1 wrote: I did manually pump the accelerator pump. I was told that this might help get fuel to the float bowl, but fuel started spraying out of it. I am not sure what this means.

Do you mean gas sprayed out the accel pump nozzle? That means you have gas in the bowl.

Thu Oct 14, 2021 8:23 pm

It sounds at this point that you likely have either too much or too little fuel. After cranking, what does the exhaust smell like? Is the choke butterfly in the top of the carb closed or open? Is the choke coil electric?

Fri Oct 15, 2021 9:40 am

I don’t want you to stray away from the troubleshooting advice above. If it was me with a carb that’s been sitting that long. For good measure and maintenance I would first take it off and clean (A can of carb cleaner) every orifice and check the float. That float may not float anymore. In my experience the Weber progressive carb can be very finicky with debris and gunk. Be careful with the manifold gasket. I did this when I was having an issue with a progressive carb. The cleaning worked great. Then I bought the correct Weber brand rebuild/refresher kit. That made a huge difference. Lots of unrelated videos to a bus on how to take apart the carb on YouTube. I’m a visual learner and not a very good mechanic. So you can do it.

Also, and this maybe difficult since you are having starting issues. If you can run it again for even a minute. You might want to make sure the rubber boots that are on the intake runners are not torn or leak. When they are cold the issue may not appear but when warmed. They might get soft and expose a leak. Old gas sitting in the rubber for years might have caused issues.

This tool is not necessary but is real nice to have. It’s thin and the will help you remove the carburetor. A lot of similar wrench’s are too thick to fit.

https://socalautoparts.com/product/carburetor-wrench-13mm/

Fri Oct 15, 2021 10:06 am

Update: I got the engine running. It is running rough and someone suggested pulling out each spark plug wire from the distributor and seeing if there is any change in the feel of the engine. When I pulled out the number 3 spark plug wire from the distributor, nothing happened(no change in the running of the engine. There is definitely spark coming from the distributor to the lead of the wire when I pull it out and it is a new spark plug. I also did a compression test previously and got over 90 psi on the number 3 cylinder. (This was on a cold engine before I could actually get it started as I was just checking to see if the engine was even worth working on to begin with).

What could be causing me to miss on this cylinder given that there is compression and spark?

Fri Oct 15, 2021 10:23 am

Check the resistance of the rotor and of each spark plug connector with a VOM.
Rotor should be 5K.
Each SP connector should be 1K.
And check that the wire itself doesn't have an internal break.
If either are open (infinite resistance) the car may run; the spark jumps the broken gap where you can't see it, but it loses energy that way.

Fri Oct 15, 2021 10:37 am

Pull #3 spark plug and see if it's wet with fuel. If so, it won't fire. Dry it out and reinstall.

Fri Oct 15, 2021 10:38 am

(duplicate)

Fri Oct 15, 2021 11:10 am

KTPhil wrote: Check the resistance of the rotor and of each spark plug connector with a VOM.
Rotor should be 5K.
Each SP connector should be 1K.
And check that the wire itself doesn't have an internal break.
If either are open (infinite resistance) the car may run; the spark jumps the broken gap where you can't see it, but it loses energy that way.

The rotor seems to be fine and the spark plug wire got a reading of around 1K. I pulled the plug and made sure it was dried, reinstalled.

It is still missing.

Fri Oct 15, 2021 11:40 am

Switch out plug 3 and 4 with each other. See if the miss follows that plug.

Fri Oct 15, 2021 11:40 am

Would it be possible to swap the spark plug and plug wire to another cylinder? This may allow you to see if the issue follows The ignition components.

Edit - looks like my response was a little late. Haha

Fri Oct 15, 2021 11:46 am

Double post

Fri Oct 15, 2021 12:08 pm

In another forum on Facebook, someone is telling me that the issue could be a burnt or stuck intake valve. They are recommending to pour engine oil down the carburetor and see if it somehow frees it.

What are your thoughts on this my Samba peeps?

Also if this is an option what type of oil and how much would I need and would this potentially gum up the carburetor.

Thanks in advance.