The Dietzl Mod

Here's how I fixed it:

I used a 3/8th NPT ot NPT connector , a 3/8 to 1/2 " hose barb adapter to fit into the 1/2 inch hole, a nut to fit on it, a pin from a trailer, and a metal strip about 1.2 inches wide and 5 inches long.

I sanded the interior of the connector so it was nice and smooth because mine had a rough edge on the inside.
Then I made a 3/8 inch hole in the metal strip big enough to thread the connector.

Here is what it looks like.


Bend the two ends of the metal strip.
There return tee is inserted into the NPT to NPT connector
The pin is used to secure the return tee. I made a few holes just flush with the return Tee and put the pin through them.

I have one of the kits from lubrcation specialist installed on my 2005 Jetta TDI. I ahve always purchased replacement filters from them. If I now go to a common vendor for the filter will it come with the larger diameter o-ring that installs on the threaded male portion of the base? If not, what size o-ring do I need?

Looks like these guys went out of business.

www.lubricationspecialistllc.com

witchcraftz said:

Here's how I fixed it:

I used a 3/8th NPT ot NPT connector , a 3/8 to 1/2 " hose barb adapter to fit into the 1/2 inch hole, a nut to fit on it, a pin from a trailer, and a metal strip about 1.2 inches wide and 5 inches long.

I sanded the interior of the connector so it was nice and smooth because mine had a rough edge on the inside.
Then I made a 3/8 inch hole in the metal strip big enough to thread the connector.

Here is what it looks like.

Bend the two ends of the metal strip.
There return tee is inserted into the NPT to NPT connector
The pin is used to secure the return tee. I made a few holes just flush with the return Tee and put the pin through them.

Click to expand...

Nice! Thanks for posting back.

armyschus said:

I have one of the kits from lubrcation specialist installed on my 2005 Jetta TDI. I ahve always purchased replacement filters from them. If I now go to a common vendor for the filter will it come with the larger diameter o-ring that installs on the threaded male portion of the base? If not, what size o-ring do I need?

Looks like these guys went out of business.

www.lubricationspecialistllc.com

Click to expand...

You need to drop the llc from that url to get the correct website. Oring size is -119

Yeah, Greg Landuyt is still in business -- he just doesn't sell the head unit for the 2-micron Cat fuel filter. I guess he decided the Nicktane unit is a better design, which it probably is.

great idea, thanks for posting guys

how do you clean your engine bay? its beautiful... dirt roads are to keep up with my cleanliness

Just did the Dietzl mod. My Thermo T was leaking to the point I had little puddles under the car when it was parked. I didn't really see the need for the thermo T with properly winterized fuel, and didn't want the option for it to start leaking again.

It was a pain in the rear trying to find the correct brass fittings. Home depot nor Lowe's carry much 5/16" of anything, and not what I needed. I had to do a combo outlet for the in and out ports.

I used Napa for everything, and used their Wix 33528 filter. It took a lot of tweaking to fit in the holster and it barely does. Are the CAT filters smaller?

Two Questions:

1. The entry fuel line is pretty scrunched up now, has anyone cut it shorter to have a better angle? I am wary to do this as it might not be easily fixed.

2. Should I still change this filter every 20k miles?

Yeah, all the 5/16" barb fittings I had to buy at my LAPS for $$. I still haven't tackled this mod but plan to when the weather turns warmer.

Here is a picture of my setup, which is very similar to the originals:

It has been at or below 20F the past few nights and everything has gone perfectly. Thats about as cold as it gets here in TN, but regardless if your fuel is gelling the Thermo T can't save you. THe filter is the Napa rebrand of the Wix 33528. Feels good knowing I am getting much better filtration. The hardest part of this was sawing of the mounting side of the headunit, which was fairly easy to do.
If your Thermo T breaks like mine did this is a very good time to get better filtration.

McDillon86 said:

ok so its like a oil filter relocation mod with better filter type?

Click to expand...

Fuel.

I recently switched from the Lubrication Specialist filter head to the Nicktane unit, and couldn't be happier. I had purchased the Nicktane filter head many months ago, but had not found a reason to swap the hardware until the weather turned really cold and I was seeing a lot more air bubbles getting sucked into the filter via the thermo-T. (The fuel was more viscous as the temperature dropped.)

Now, no more air bubbles. The advantage of the Nicktane unit is that all the hardware is provided; the advantage of this product is that it is much cheaper.

I've got all the parts I need for the Dietzel mod and I plan to do it tomorrow. I want to make sure of one thing. When I delete the thermal-t, I simply splice the two lines that used to go to it together with a 5/16" hose splicer, correct?

Jon

jonlowe said:

I've got all the parts I need for the Dietzel mod and I plan to do it tomorrow. I want to make sure of one thing. When I delete the thermal-t, I simply splice the two lines that used to go to it together with a 5/16" hose splicer, correct?

Jon

Click to expand...

Yep that is what I did.

What is every one using to seal the threads on the plugs? Also make sure that you have the correct size allen wrench for the plug I believe it is a 3/8in because the 10mm is to big and the 9m is to small. I had to use a 8mm and some small standard allen to get it tight and it did not work so I'm going to but a standard set today and make sure that it is tight (I have air in my line over night but i think its the hoses going bad 11yrs old).

Phantomofheat said:

What is every one using to seal the threads on the plugs?

Click to expand...

On that head I'm currently using teflon tape with no leaks but if you want to use thread sealant make sure it is diesel-rated like this stuff is: http://www.dieselorings.com/gasoila-diesel-rated-paste-thread-sealant-2oz-tube.html

would this essentially produce the same result, as in eliminating a leaky thermo T?


http://www.ecstuning.com/Volkswagen-Jetta_IV--TDI/Search/Fuel_Filter/ES2537827/

mod looks good but the above is 1/2 price

Any folks complete this on a B4/A3? I had some recent thermo tee issues, decided to go for this, but realized after the setup I was unable to fit the larger filter & base setup (Wix 35528 filter and Wix 24770 base) in the designated area...

simbolo said:

would this essentially produce the same result, as in eliminating a leaky thermo T?

http://www.ecstuning.com/Volkswagen-Jetta_IV--TDI/Search/Fuel_Filter/ES2537827/

mod looks good but the above is 1/2 price

Click to expand...

Yes, as many have already mentioned this is a good option if all you want to do is eliminate the thermo tee.

If you want to get better fuel filtration as well, then the OP's system is the way to go.

No mention of the filtration size on the ECS unit. There are a few advantages to this and other aftermarket fuel filter scenarios, primary being the 1-2 micron filters available. Cost, thermal-T, air bubbles, etc. are all additional benefits but perhaps secondary. The only thing missing is the water drain. Personally I've never used mine, or had to...

DanG144 said:

Yes, as many have already mentioned this is a good option if all you want to do is eliminate the thermo tee.

If you want to get better fuel filtration as well, then the OP's system is the way to go.

Click to expand...

I saw it mentioned in previous posts but could never find it.

I have never seen this filter on any vendor sites before, I was surprised to see it come up in a search for "fuel filter" even though the vehicle specified was a 2002 tdi, go ECS!

Is there a better place to get these?

Sorry to bring this back up. Everyone still happy with this mod? My tee started leaking air into my system so I just ordered the necessary parts and a Cat 1R-0750. Looking forward to it

Getting rid of the thermo-T is a very good idea, however you do it and no matter which generation TDI you have. No need to apologize about bumping this thread back to the top, where others can find it more easily.

Also, I firmly believe that the Cat 2-micron filters contribute to a longer life for the injection system. A couple years ago I bought a used low-mileage injection pump for my 2003 Golf, so I'd be ready when the original one finally dies. But the original now has 507k miles on it and still no sign that it will need replacement anytime soon.

Need clarification - maybe a picture

witchcraftz said:

Here's how I fixed it:

I used a 3/8th NPT ot NPT connector , a 3/8 to 1/2 " hose barb adapter to fit into the 1/2 inch hole, a nut to fit on it, a pin from a trailer, and a metal strip about 1.2 inches wide and 5 inches long.

I sanded the interior of the connector so it was nice and smooth because mine had a rough edge on the inside.
Then I made a 3/8 inch hole in the metal strip big enough to thread the connector.

Here is what it looks like.

Bend the two ends of the metal strip.
There return tee is inserted into the NPT to NPT connector
The pin is used to secure the return tee. I made a few holes just flush with the return Tee and put the pin through them.

Click to expand...

I'm not quite sure I'm following you on this. Could you perhaps show a picture? I know this is an old thread(and you may not even be an active member now), but I am stuck right now trying to figure a way to tie the tee back into this. I am getting excessive fuel temperatures (enough for the McMaster Viton hoses I replaced on my in-tank lift pump to degrade and burst at the plastic barb connections on the lift pump assembly)

I can figure out a way to do this via hoses and clamps, but I'd rather gain insight on what you did here.

Also, does anyone know if the Thermo tee has to be mounted just as it sits stock( where the arrow on the 'top' is visible) or can it be mounted in a turned position ( where the arrow on 'top' is turned to one side or the other)

How the hell did u get that engine bay so clean?

The thermo tee should work in any position, as far as I can tell.

DanG144 said:

The thermo tee should work in any position, as far as I can tell.

Click to expand...

Thanks DanG. I was assuming it could be, but wasn't quite sure. In my old Thermo tee, just holding it and turning it over in my hand I can hear a rattle on the inside of it and depending on which way I have it turned in my hand, the piece that is loose on the inside will 'fall' to the bottom, if that makes sense. My thinking is that the loose piece is either the spring on the inside and/or the valve that diverts the fuel flow so I'm wondering if the tee has to be direction-oriented (I.e. A 'top' side and a 'bottom' side) for the valve on the inside to properly work. I don't know the geometry and inner workings of the tee so I'm not sure.

As for adding the Thermo tee to the adapter pictured in this thread, I was considering drilling a hole in the top of the unused inlet port with either a 33/64" bit or a 13mm bit (just slightly larger than the piece on the Thermo tee that sits in the fuel filter. My cheap calipers says it is 0.5065" or 12.85 mm) this in theory should work; however, with the thermal expansion of the cast material that the adapter is made of, I'm afraid it may leak once it gets hot(using an IR temp gun, I have seen 150 F temps on the top of the adapter surface)

DanG, what is an acceptable fuel temperature? Is 150 F a little too hot? Do you think with me adding back the Thermo tee that it might lower the temps somewhat since the engine will burn up most of the recirculated fuel before the Thermo tee triggers and sends the hotter fuel back to tank? It's been 100+ degrees here in Texas this summer so far and I wasn't having issues (like the green Viton hose from McMaster-Carr bursting). The only thing I can think of is the temperature is getting too high and acceleraties the hose to degradation where it will burst.

having trouble finding the barbs.. etc

That engine bay!!!

ok so couldnt find 1/2 to 5/16.. 5/16 to hose barb.. but i did find this...


1/2 to 1/4 ... 1/4 to 5/16 hose barb.. does this work.??

or should i be doing this instead?

3/8 MIP 5/16 FIP and 3/8 to 1/2 bushing

so 1/2 to 3/8,,,, 3/8 to 5/16 hose barb.. seems like 1/2 to 1/4 , 1/4 to 5/16 presents a slight choke point as 1/4 is basically 4/16

I have two Nicktane filters on order for my green Golfs. Blue Golf I recently acquired has one: it's previous owner (a member here) has been a big influence on me about these cars and he's always been dead-on- he had consulted one of the top injector folks (also a member here) who had told him that some injector problems he'd had were attributable to insufficient filtering, recommended the Nicktane (or perhaps just the level of filtration- CAT filter is 2 micron).

Speaking of clean engine compartments, I have to show off my son's Golf (acquire this year from the original owner); if one didn't know any better one would swear this car is no more than 2 years old (this is how the car came, no cleaning at all):