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Engine Specific Info and Questions => IDI Engine => Topic started by: dontdoemyourself on November 01, 2015, 05:16:36 pm

Title: AAZ power loss, idles and starts fine
Post by: dontdoemyourself on November 01, 2015, 05:16:36 pm
I'm at a loss.. Car was running fine on my way to a hike.. Then on the way home i could it get it to rev over about 2,000 rpm. White smoke.. Some small air bubbles in the outlet line.. Couldn't see air in inlet line.. Drained water and some really really nasty crud out of fuel filter.. (Thinking  clogged injector?) car won't run without the cold start lever pulled out.. Checked my timing, reset cam to crank timing and checked IP timing.. Set to 1.0mm. Pump was rebuilt by Giles in June.. Next step is to test to see if all injectors are firing, they were rebuilt too.. Then compression.. Any additional ideas of things to check?
Title: Re: AAZ power loss, idles and starts fine
Post by: TylerDurden on November 01, 2015, 05:31:25 pm
I'm thinkin your filter is stuffed.  High vacuum on the inlet side due to the restriction can draw air into the system through the main seal or banjo.

I'd feed it from/to a clean container of fuel to verify all else is ok.

Could be someone vandalised your fuel tank.
Title: Re: AAZ power loss, idles and starts fine
Post by: vanbcguy on November 01, 2015, 08:07:28 pm
Yup, start with a new filter, if you were getting crud draining out the bottom it's probably plugged up.  Are you missing your filler cap? Do you have a locking one?
Title: Re: AAZ power loss, idles and starts fine
Post by: dontdoemyourself on November 01, 2015, 09:16:16 pm
This vanagon eats fuel filters! I think this is my second filter within 6 months! I might need to replace my fuel tank too.. The previous owner was running this on SVO when I bought it,  and Im sure the crud is because of that.. I do have a locking fuel cap, and I have been running NAPA filters.. Which aren't that nice.. I'll get a German one tomorrow and see how long it lasts.  Thanks!
Title: Re: AAZ power loss, idles and starts fine
Post by: vanbcguy on November 01, 2015, 09:40:41 pm
This vanagon eats fuel filters! I think this is my second filter within 6 months! I might need to replace my fuel tank too.. The previous owner was running this on SVO when I bought it,  and Im sure the crud is because of that.. I do have a locking fuel cap, and I have been running NAPA filters.. Which aren't that nice.. I'll get a German one tomorrow and see how long it lasts.  Thanks!
Gotcha. Cleaning out your tank would probably be a good start. If you're burning through filters then you've got contamination for sure.

Algae is another possibility. There's a variety of black algae that can grow in diesel. In particular tanks with water contamination! If you're getting water from your filter then you need to find the source.
Title: Re: AAZ power loss, idles and starts fine
Post by: TylerDurden on November 02, 2015, 04:24:17 am
If you're getting water from your filter then you need to find the source.
Agree.

In the meantime, I'd probably put on some cheap filters and dump a gallon of naptha into the tank and try to dissolve as much goo as possible.

The vanagon tank system is convoluted and not easily just dropped and cleaned.

Still, first I'd bottle feed to see if the engine/pump/injectors are ok.
Title: Re: AAZ power loss, idles and starts fine
Post by: air-cooled or diesel on November 02, 2015, 06:15:28 am
ive never had a problem with napa filters, check if its a wix filter, which would be fine to use. try bottle feeding with diesel purge; like said above you need to flush fuel tank forward, water separator needs some type of cleaning too. try to flush out lines forward(to filter), maybe take to a good shop which can do sometype of flush out
Title: Re: AAZ power loss, idles and starts fine
Post by: libbydiesel on November 02, 2015, 06:25:34 am
I've seen a fair amount of hand-wringing about dropping the vanagon tank, but assuming it's 2WD, the vanagon fuel tank is quite easy to drop.  The hardest part being draining the tank.  The system has the complication of the three top grommets and crossover tube because of the valley in the middle of the tank.  It is not easy to clean the inside of the tank as the only real access points are the fuel filler opening and the sender opening and both are fairly small.  Replacement tanks are readily available.  The last one I got, I paid $80 delivered.  I took a little time and care with a fine file to remove burrs at the sender hole.  It has worked fine. 
Title: Re: AAZ power loss, idles and starts fine
Post by: dontdoemyourself on November 02, 2015, 09:28:25 am
Thanks, this is good info. I'm not sure what naptha is.. But I'll find some.. I looked on rockauto,  they've got a new tank for $120.. I might go that route. Put a new filter in and still getting air.. Checked my copper o rings and they seem smooth.. Wondering if my line between tank and water separator is leaky.. Could the water separator be faulty..?
Libbydiesel, where'd you get an $80 tank?!
Title: Re: AAZ power loss, idles and starts fine
Post by: air-cooled or diesel on November 02, 2015, 10:05:48 am
I'm thinkin your filter is stuffed.  High vacuum on the inlet side due to the restriction can draw air into the system through the main seal or banjo.
all that clogging needs to be cleaned out, ^ 1st place id start. i dont know what to tell you until you get a new tank, or clean tank, water separator, fuel lines. you can bottle feed with purge, and sea foam, but that should be a good fix for post-filter.
Title: Re: AAZ power loss, idles and starts fine
Post by: libbydiesel on November 02, 2015, 10:54:22 am
I got the tank off eBay.

The stock tank has a tube from the outlet to the center of the tank.  If that tube gets a crack in it, it can draw air into the even when there is still a fair amount of fuel in the tank.  When it gets bad enough, it acts like you have run out of fuel entirely when the tank is half full.  That is the issue that inspired me to replace my tank.

 
Title: Re: AAZ power loss, idles and starts fine
Post by: dontdoemyourself on November 02, 2015, 04:26:22 pm
Libbydiesel- thanks, I'm going to order a new tank tonight, I have some hard plastic fuel lines from a mk3  gas Jetta that I plan to use for feed and return lines ( will these work?)
I will bottle feed some purge and seafoam before I connect everything back together.. This has kind of been a plaguing problem... And I can have a chance to change out my squeaky shifter bushing that is hiding under the tank.
Title: Re: AAZ power loss, idles and starts fine
Post by: libbydiesel on November 02, 2015, 04:45:17 pm
The hard plastic lines will work.  I like to use clear tygothane for coupling, though, so I can easily trace air infiltration. 
Title: Re: AAZ power loss, idles and starts fine
Post by: dontdoemyourself on November 09, 2015, 10:56:00 pm
Old tank out, filler neck was incredibly nasty as well..(http://images.tapatalk-cdn.com/15/11/09/0507a95894d6b8b9fc45a7107ecd113c.jpg)
(http://images.tapatalk-cdn.com/15/11/09/11fa996db5fd896ef61dfca8cb889f50.jpg)
(http://images.tapatalk-cdn.com/15/11/09/9489764c47fdaa616f0a624a65fa7078.jpg)
(http://images.tapatalk-cdn.com/15/11/09/9381cc0d607587443603ebc84b7849b3.jpg)  also shows my clever backwoods shift bushing replacement made out of an old bmx crank spacer and hose clamps.
Put a pre filter right after my tank, and made new lines, she's running like a top.  Ran from the can of diesel purge for a bit.
After finally getting to use my boost gauge I see I'm only making 9 psi.. Now on to that ..
Title: Re: AAZ power loss, idles and starts fine
Post by: libbydiesel on November 10, 2015, 12:34:23 pm
9psi is normal unless you have adjusted it/added a manual boost controller.  Which turbo?
Title: Re: AAZ power loss, idles and starts fine
Post by: dontdoemyourself on November 10, 2015, 08:55:05 pm
I have a t2 with a needle valve that is totally closed off, disconnecting the wastegate. I have messed with the wastegate arm in the past, I could have it misadjusted. I may uninstall my intercooler and see if that helps at all.. If it means anything, I might pick up an air research t3 and aluminum intercooler this weekend,  hoping to build with 360 bearing and keep it in a budget, but the goal is 15-17psi intercooled...
Title: Re: AAZ power loss, idles and starts fine
Post by: libbydiesel on November 10, 2015, 09:36:26 pm
Without a boost signal to the wastegate, that turbo shouldn't have any trouble producing more than 9psi regardless of whether or not the intercooler is in place.  Is your wastegate being held shut properly?  Are you properly fueled?  What are your EGTs?
Title: Re: AAZ power loss, idles and starts fine
Post by: dontdoemyourself on November 10, 2015, 09:54:05 pm
Egt's are topping out around 1250-1300 under full load going uphill, towing a load.. Going highway speeds 60-65 mph Under normal hard driving on flat roads more like 750-900. Coolant temps can get a little high in the heat.
I know Giles left me some more room to turn the max fuel up. And yes, as far as I can tell the wastegate is keeping it closed.. I preloaded it just a little..I may take my exhaust off to see if it is clean though. The t2 from what I've read can handle 16 psi or so, but for how long?
Title: Re: AAZ power loss, idles and starts fine
Post by: dontdoemyourself on November 11, 2015, 06:37:37 am
Well, scratch that.. Engine blew up this morning.
Title: Re: AAZ power loss, idles and starts fine
Post by: libbydiesel on November 11, 2015, 07:27:34 am
Wow, sorry to hear that.  What happened?
Title: Re: AAZ power loss, idles and starts fine
Post by: dontdoemyourself on November 11, 2015, 09:22:37 am
Started to lose power going up a hill, then tried to downshift and it ran away a little, so I turned around and tried to limp 8 miles back home and made it about 2 before I totally lost power. Threw the number 4 rod. Through the block. When I tear it apart I'll be able to tell what happened for sure... Not sure where I can find a new long block..