I know I've asked before but cant find the thread
130 engine
I wanted to lift out the fuel filter to access and achange the temp sender and was reminded
that this thing makes it a bit more tricky.
As it's connected to both fuel and coolant I guess it's maybe some kind of fuel heater?
do I need it ?
can remove/dispense with it?

 

Quote from: regw on May 07, 2023, 05:55:42 PMI know I've asked before but cant find the thread
130 engine
I wanted to lift out the fuel filter to access and achange the temp sender and was reminded
that this thing makes it a bit more tricky.
As it's connected to both fuel and coolant I guess it's maybe some kind of fuel heater?
do I need it ?
can remove/dispense with it?

 

Yes that is a heat exchanger, in theory you could dispose of it if you link the fuel pipe and coolant pipe up once it's removed

Ahh
After some googling I found a pdf which tells me its actually a cooler to prevent
excessively hot deisel being returned to the tank
I'll leave it be then.

i did manage to get my hand to the sender and wiggle it a bit
now the odd symptoms* have gone so it may have been a poor contact
but oi have new sender ready just in case

* odd symptoms like the glow plug light staying on and acting as if its
a freezing cold January morning and erratic temp gauge readings

Heres the link to the pdf if anyone is interested
section 13 describes the heat exchanger
https://myarchive.us/richc/VW_TDI_with_PumpeDuse.pdf

Does yours not have an air cooler under the floor below drivers seat then?

Just had a look and dont see one, wish it had rather than the somewhat over engineered
thing that's in there now.
Maybe its exclusive to the 130 engines?

Possibly as mine was a 115 engine and definitely had air cooler under the floor.

It's playing up again so this weekend I'll start whipping stuff out to get the sensor
I'll remove the scuttle to do the cabin filter as well so hopefully make it easier access.

Well I got the new temp sensor in after some faff as I was initially sent the wrong sensor
(a 4 pin not a 2 pin one)
so I had put it back together and do it again yesterday
Here's a few pics and words for anyone else with a 130 lump and fuel cooler

This is what you find under the bonnet in front of the fuel filter


With the pipes disconnected you can fold the cooler out of the way but the bracket
is best removed too for better access to the temp sensor
its only 2 10mm headed bolts and 2x 4mm headed hex bolts for the cooler.



Here's where the temp sensor lurks with the new one in on a temporary basis



Its not easy to see looking down and you can see how the cooler bracket doesn't help if its left in place



New one in and all clips double/triple checked they're all fully home



After reconnecting all the hoses and topping up the coolant I ran the engine to check for fuel and coolant
leaks, none happily.
I got it up to about 65 degrees and checked the gauge against my IR thermometer on the block and pipework
and they both matched pretty well so the new sensor appears to be doing its job.
I replaced the cabin filter while I was in there.
Scuttle and covers back on now and I hope that's the end of that saga.