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Sun Aug 31, 2014 5:07 pm

Finally able to take the van out in a few trips. I have noticed that it doesn't want to start after it gets warm/hot. Once it cools, it usually starts but last time it needed a jump. It turns, just acts like it's not getting enough juice. Battery voltage is good. Haven't had a chance to check the voltage at the starter yet. Maybe a ground issue (not sure how heat would effect that)? Maybe a temp sensor?
Read about a heat soak issue with the starters, but I think that they don't turn at all with that condition. Any thoughts?

Sun Aug 31, 2014 5:22 pm

battery may be getting hot.
does the exhaust have it's heat shield?

Diesels are supposed to be easier to start warm than cold.

Sun Aug 31, 2014 5:41 pm

Yes but the tailpipe fell off...lol

Sun Aug 31, 2014 5:42 pm

I'm plugging the block heater in to see if it has the same condition or not.

Sun Aug 31, 2014 7:13 pm

Next time you get it warmed up and it won't start, just unplug the temp sensor and see if it starts. Your glow plugs will stay on longer so becareful.

Mon Sep 01, 2014 8:57 am

So now it won't start at all. Checked the connections, that all seem good. I'll take the starter in next weekend and have it bench tested to know for sure.

Mon Sep 01, 2014 4:27 pm

...do you mean "The starter does not turn the engine over" or
"The starter turns the engine over but it never catches and runs"?
If the starter turns the engine over merrily but no ignition then suspect fuel delivery/injection problems first. But this would be unusual. Possible problem with the fuel cutoff solenoid in the injector pump?
If the starter has a hard or impossible time turning the engine over when it is hot then first check high-current system: battery and starter cable plus ground jumpers and connections. Start with the battery (maybe borrow a known good one for test?) to make sure it has the "oomph" to turn over the engine. If battery seems good, then check both battery and ground cables and connections. Does the solenoid "click" on the starter when you turn the key on to start?

Tue Sep 02, 2014 8:48 am

Which diesel engine? The stock 1.6 NA? It is possible the engine is wearing out if it cranks but won't catch hot. When cold, the glow plugs preheat the fuel charge, when the engine is hot, the glow plugs are not functioning. The engine depends on good compression to start.

If the engine is not cranking, that is a completely different problem. A stock diesel requires almost no voltage to actually run. Just a 12 volt signal to the injection pump fuel cutoff switch. It is possible to run the engine probably for a month with a good battery and no charging system. We will need more information to assist you further.

Tue Sep 02, 2014 4:05 pm

It is the stock 1.6. It used to start after cooling. However now it doesn't start at all. The starter turns but "fades" like the battery is dead/dying, but the battery has a charge of 12-13 volts. It may be a wiring issue but since it has gotten worse over the course of a few weeks I figure it's the starter going out. I'm thinking I can have the starter tested and confirm or rule that out first.
I thought fuel problem when it first started but now it seems more electrical.

Tue Sep 02, 2014 5:47 pm

You might learn something by reading this thread:
http://www.thesamba.com/vw/forum/viewtopic.php?t=603577&sid=1479aba76224599d2a616d3e1d689f7f
Where Mr. Emerson had voltage loss in his system. Page 6, I think, he discovered the primary culprit: a bad transmission to body ground cable. Your battery grounds to the body, your starter grounds to the engine but since VW started shockmounting their engines 45 ears ago you have absolutely needed a solid grounding strap between the engine and the body. Otherwise you are relying on random little metallic things for ground, which can impair the ability of your starter to operate.
By all means get your starter checked, take the battery in at the same time to make sure it has enough ooomph to crank the starter - diesels take a lot more amps to turn over when starting than gas engines do. While you are under the van looking up at the starter, take a good look at the ground strap just forward of the axles, from the nose of the transmission to the body.
This isn't high-tech and you can always add another grounding jumper between a convenient point on the motor and the chassis to make sure you have good connection.

Wed Sep 03, 2014 5:35 am

Yeh I noticed that the ground you mentioned looked aweful. Uninsulated wire with nasty connections. I had planned on replacing it regardless. Didn't know it was so crucial to the starter. Now I may replace it and clean the connection points before removing the starter. May save me some work.

Wed Sep 03, 2014 8:12 pm

FWIW, it is not critical to use that particular braided strap for a grounding connection. It is important to have a solid ground. A heavy (like at least #4 for a diesel) battery cable from your FLAPS will work admirably.
I added a supplemental ground wire from the block (there are two 8mm threaded holes in the side of the block just forward of the injector pump that work well) to the top bolt of the Right Rear engine carrier mounting. (I used a piece of #2 wire, it is the black wire below the hoses). Use 10.9 grade bolts into the block so you can torque them down tight without snapping, and star-type lockwashers to dig in for a great connection.
At the same time I replaced the battery ground cable with a heavy one (#2/0) also bolted directly to the block (in the other threaded hole, it is the black wire between the hoses) figuring that the heaviest current draw was the starter so it now has a direct route back to the battery. (For you non-diesel owners, the battery is in the right/rear of the engine compartment for a diesel to keep the starter cable run shorter). And I added a #8 jumper to a post on the back of the alternator (the brown wire in photo) so have the main electrics well grounded now.

Thu Sep 04, 2014 9:59 am

Dampcamper wrote: It is important to have a solid ground. A heavy (like at least #4 for a diesel) battery cable from your FLAPS will work admirably.

Pardon my acronym ignorange (and I'll probably just shake my head and think "I should'a known that...) but what is / are FLAPS? As referred to in the quote above?

Forgive my detour of the original posting.

Thu Sep 04, 2014 10:56 am

Friendly
Local
Auto
Parts
Store

Like AutoZone, O'Reilly's, NAPA, (does Canada Tire count? They've saved me a couple of times.) Or any other generic auto parts store. As opposed to your VW specialty shops. So, say for the braided ground strap on the nose of your transmission, they mightn't have the VW part but they would have a short piece of heavy cable with lugs on each end that could work as a replacement. And all kinds of hinky accessories.

Thu Sep 18, 2014 4:55 pm

I think I may have found the culprit. I noticed some air bubbles in the line. So I removed the line and submerged it in a container of diesel and no bubbles. So I thought, "I'll change my filter this weekend". Later this week I had the non-starting condition again and noticed a large bubble in the line. I had my wife try to start the van and noticed that the bubble didn't move. So I removed the line and again submerged it in a container of diesel, and it fired right up. So I am thinking it is either a clogged filter or pickup tube.
Now anyone know why this would get worse after the van is warm?

Thu Sep 18, 2014 5:00 pm

Remove your fuel tank cap and see if the issue persists.

Thu Sep 18, 2014 5:19 pm

Will try! Thanks for the extra suggestion.

Thu Sep 18, 2014 5:26 pm

If it doesn't occur with the fuel tank cap removed, it would indicate an issue with your tank vent.

Tue Sep 23, 2014 1:17 pm

Tried removing the cap and no difference. I am going to replace the fuel filter next and add some anti-gel to the tank.

Tue Sep 23, 2014 1:24 pm

The engine needs to crank at a fairly good rpm to start. You describe a poor cranking condition above. There should be a clear line between the filter and pump. When the engine is running, there should be no bubbles in the line. Bubbles indicate a restriction or air leak and need to be addressed. Did you try disconnecting the glowplug sensor wire? That would cause the glow plugs to work every time you crank the engine hot or cold. That wont help the poor cranking you describe, but might aide in starting an engine down on compression. These diesels are pretty basic.