Author Topic: A few issues with a gas/diesel swap  (Read 4459 times)

March 23, 2011, 12:51:31 pm

Patrick

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A few issues with a gas/diesel swap
« on: March 23, 2011, 12:51:31 pm »


Here's what I'm dealing with.
http://www.vwdiesel.net/forum/index.php?topic=28542.0

Several problems at the moment.
1)  Not sure what to do with the mass of wires going to the fan/fanstat (Air conditioned car, getting deleted). THe other car (non air) ran everything with 2 wires, red (live?) and brown (ground?).
Anyone got a simple diagram of how this is supposed to be wired? 2 speed fan/fanstat.

2)Also need to figure out which line from the back feeds fuel, and which one is return. I'm assuming there's a pump back there somewhere I need to eliminate too....

3) Anyone know what colour the wire is on the coil I need to move to the shutoff solenoid?

4) Can I put the  glow plug relay in the right spot in the  fuse panel and just run the red wire off the right spot or do I need to get more involved?



Reply #1March 23, 2011, 01:58:18 pm

rallydiesel

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Re: A few issues with a gas/diesel swap
« Reply #1 on: March 23, 2011, 01:58:18 pm »
I did the a/c delete and removed all the wires. I will look and see what wires went where.
2006 Jetta TDI - gtb1749v, Malone 2, Frank's Titan 2 cam, VR6 clutch....
1991 Jetta TD - sold :(
2001 Golf TDI - Son's
1981 Rabbit - BEW tdi swap project

"ONCE YOU GO CLACK, YOU NEVER GO BACK"

Reply #2March 23, 2011, 04:07:16 pm

Patrick

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Re: A few issues with a gas/diesel swap
« Reply #2 on: March 23, 2011, 04:07:16 pm »
I did the a/c delete and removed all the wires. I will look and see what wires went where.
Thanks. The whole harness at the front currently hooks to a plug with a single red/white wire, and another plug with one red, one brown.
the doner runs it all with one red, one brown, but they're bigger wires too.....

Removed a pump/reservoir that was mounted where the water separator would be on the diesel. Is there another pump in the tank?    
Also took a "digifant2" brainbox out from under the cowl. I've got lots of gasser parts if anyone wants them cheap..... Engine ran fine, started right up even though it had been sitting for at least 2 years. The whole complete engine is up for grabs, along with the brain box, the air filter housing, anything else that's useless to me.. I'm keeping the trans though.
« Last Edit: March 23, 2011, 04:29:09 pm by Patrick »

Reply #3March 23, 2011, 06:20:47 pm

rallydiesel

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Re: A few issues with a gas/diesel swap
« Reply #3 on: March 23, 2011, 06:20:47 pm »
I took a look. All you need to run the fan is one red wire from the harness. This red wire splices to the red wire on the thermoswitch plug. The red/white thermoswitch wire splices to the red/white from the fan motor plug. The red/black wire from the thermoswitch plug splices to the red/black from the fan motor plug. Finally, the brown wire from the fan motor plug splices to any ground.

The rest of the stuff can be removed such as the series resistor on the fan shroud, the pressure switch on the a/c hardline, etc.
2006 Jetta TDI - gtb1749v, Malone 2, Frank's Titan 2 cam, VR6 clutch....
1991 Jetta TD - sold :(
2001 Golf TDI - Son's
1981 Rabbit - BEW tdi swap project

"ONCE YOU GO CLACK, YOU NEVER GO BACK"

Reply #4March 24, 2011, 05:58:40 am

Patrick

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Re: A few issues with a gas/diesel swap
« Reply #4 on: March 24, 2011, 05:58:40 am »
Thanks. Going to see if I can take today off work and get it running...
Still don't know if there's a second pump in the tank, I seem to remember running into that on a fox a bunch of years ago.

Reply #5March 24, 2011, 01:49:06 pm

Patrick

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Re: A few issues with a gas/diesel swap
« Reply #5 on: March 24, 2011, 01:49:06 pm »
Hooked the fuel lines at the tank together (after pumping out the gas), put 5 gallons of diesel in it, hotwired the glow plugs, and it runs. Everything works like it's supposed to (idiot lights etc).

Wired the fan the way I think it's supposed to work, we'll see when it gets hot enough.

Went out after lunch and pulled a glow plug relay and the big wire that runs the glow plugs, put the right relay in the right hole on the fuse panel and hooked the wire in where I pulled it on the other car, and good news, it works. Plug and play.... no light to tell me it's working, but I can live without it for the time being.

Still have a leak to deal with at the fuel filter. THe gas engine ran a bigger return line than the diesel.

NExt project is the safety!

Reply #6March 25, 2011, 11:46:32 pm

8v-of-fury

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Re: A few issues with a gas/diesel swap
« Reply #6 on: March 25, 2011, 11:46:32 pm »
Gas engine probably had a larger LPH number.

Congrats on the swap! I have just recently (in the last 2 months) completed two Gas->Diesel swaps myself. Both cars were 1984 Jetta's with the 1.7 CIS engine, and I swapped a 91 1.6TD in to one, and a 91 1.6 N/a in to the other. LOVE IT. Diesel is the way to be.

Did about 200kms today on a little over 1/8th of a tank! Intense. Purely Intense!

Post up some pictures :)

Reply #7March 26, 2011, 07:36:41 am

Patrick

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Re: A few issues with a gas/diesel swap
« Reply #7 on: March 26, 2011, 07:36:41 am »
Used to have a 2 door 84 jetta same colour as the one in your picture, 1.7 with a 7A trans, was a good car until the seat decided to go through the floor! traded it off for the BBS rims I'm runnig on the jetta. I like mk 1 cars, but I think the wife would give me an awfully hard time about a 30 year old daily driver. Besides, where do you find a good clean body up here that old? Still like to do an old scirrocco though...

Should be done today. Checked the back brakes and changed out the back struts thursday night (Passat springs to get rid of the sag) Just have front brakes and front strut bearings to do. Then it's off to my mechanic for a new 2 1/2" straight pipe and a safety. should be able to plate it monday....  

Been reading the FAQ about making a gas tach work on the w terminal, haven't decided how/if I'm going to tackle that. Should hook up a glow plug light too.....
« Last Edit: March 26, 2011, 07:40:28 am by Patrick »

Reply #8March 26, 2011, 06:32:39 pm

Patrick

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Re: A few issues with a gas/diesel swap
« Reply #8 on: March 26, 2011, 06:32:39 pm »
Drove the car home from my neighbor's shop, dammed self adjusting clutch cable is adjusted up too tight, can't get it to let go. Anyone got any tricks to get them backed off? Both cars are the same... Think I'm probably ordering a clutch cable on monday.

Reply #9March 31, 2011, 06:21:43 am

Patrick

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Re: A few issues with a gas/diesel swap
« Reply #9 on: March 31, 2011, 06:21:43 am »
Car is up and running. Got it back from the safety yesterday, have to get to the mto today so I can drive it. Garage left the gas mufflers in it and just hooked them up. I'll leave it like that for a while, but I think it's getting straight piped again when it fails. Felt a little lazy on the way home....
Temperature guage isn't working. The gas engine had 3 sending units on water necks (all 2 wire). The diesel has one 2 wier, one 4 wire. I'll try swapping out 2 wire units to see if one will work. If not it will be mess with the 4 wire one Which was hooked in teh diesel car) to see if I can get it working. Starting to think MAYBE I was too quick with the side cutters for all the extras....