Whats the Webasto box?

[whitelion58]

Hello
spent some time doing a major service on the newly acquired CDT this weekend, and generally getting to know the car. Never had a 75 before, but spent 35 years mending cars and currently have four Rover 827's as well.

Anyway, done all the jobs under the bonnet that I think I need to:
Air, Oil and Fuel and Pollen filters - all absolutely black so I think its not been touched for a while. PCV was just a congealed black mass, so new filter there too. EGR bypass, after scraping a 1/4" think ring of gunk off the intake.

Checked the plenum and found standing water and a soaked pollen filter. Poked out the blockage and 2 pints of stinky water and leaves dumped on the floor. A Jules shield and the inspection hole/grommet now installed.

Reversed the bonnet release splitter and greased the catches. New pressure cap seals on the way.

Mulling over doing the inter-cooler O-rings - the large rubber pipe feeding into the EGR had oily deposits on it, is that a possible clue?

I suspect it is running cold - only got 37mpg on a 250 mile trip over the Pennies. Not actually used the dash diagnostics yet, just lack of time. Have a new stat/housing on the way anyway so will just knuckle down and fit it soon as I can.

I think that covers most stuff?

Anyway, I do not have a manual so wonder if you can help me identify an unknown bit of kit? Whenever I open the drivers door, a motor whirs away under the bonnet. It runs a few minutes, then stops. Starts again if I shut the bonnet I notice. Anyway, its coming from the box bolted to the front face of the battery box, and bears a Webasto label, and has its own air intake duct.

No clue what it is, so can someone enlighten me?

Thanks in advance - and also thanks for the great archive which I have thoroughly raided for all the job so far.

Cheers
Tim

[kiowa]

Fuel burning heater.It help the engine to warm up faster do a search for FBH and will find loads about them

[r44flyer]

Dash diagnostics doesn't take long and if your running temp is ok you'll save yourself a ball ache of a job.

How's the performance? Poor response under 2000rpm and ****** all over 3000 suggests maf problems which will also affect economy. If that's ok, get it on a T4 to investigate the injectors. Mine suffers from poor economy (although it's a manual) and gave me 37mpg as well, on a run. Injectors are the current suspects.

[whitelion58]

thanks for the replies - rather suspected it was an FBH, so will go do some research then.

Performance seems okay, not that I have much to compare it to. Certainly not a patch on the 827's :-) It actually feels livelier after this weekends attention, but have not had it on a decent run since.

thanks again.

Tim

[whitelion58]

Now done the stat. Not particularly difficult I thought (though I do have small hands), but did take a steady four hours, including a lunch break. Also changed the intercooler O rings, which were a total mess and the whole area was covered in oily filth. Again, a very straightforward job and a cheap fix.

Finally, I did all the research on the FBH and gave my PCB to an electronics geek friend who changed the 3 resistors in no time in exchange for a couple of beer tokens. Refitted it , earthed pin 3 and it all sprang to life. Result.
This morning it was 1.5 degrees outside, and the FBH fired up and did its magic.
Car was running bang on 90 degrees in no time, so very pleased.

Did another mpg calc over 440 miles commuting to work - at least 1/3 of which was before all the servicing. Now showing 42mpg, which is pretty encouraging.

Also fitted after-market reverse park sensors which do help.

Overall, an excellent car and should stay that way for a while I hope!
Tim