J Tubes

[Sittingonthedockofthe BAY]

Hi just need to clear this up,what are the diff with j tubes and heat exchangers as i am just about to fit a new engine to my 1970 bay and need all the tips i can get heat ect....Richard.

 

[Araon]

J tubes are used in replacement of exchangers, frees up the exhaust (less restrictive) but you wont have heating, you need to block off the tinware which will give the added benefit of cooling the oil a little more.

 

[Loxy]

J tubes = no heat whatsoever as they are just extensions of the exhaust with no provision for providing heat to van. Generally bigger bore than heat exchangers, so potentially useful for a badboy engine (I think you can buy big bore heat exchangers from somewhere though).

With heat exchangers its worth trying to find original ones rather than repro as they have more fins and are a lot more effective at providing heat (assuming all the ducting is in good condition).

 

[Guest]

whack on a set of j tubes, buy a propex or webasto rig it to the og heating for instant heat and more power to the engine... bish bash bosh sorted

 

[froggy]

How are webasto's fitted and where to?

 

[Guest]

they are the same as propex except the run on petrol/diesel so you can pipe them from the fuel tank and come with all the nesessary gubbings but are not as cheap as propex units. a brand new webasto petrol will retail @ £500-600, second hand fleabay same as a good propex.

 

[Tofufi]

Personally, I'd run original VW heat exchangers. Fully working, the system isn't too bad. Except for when you are camping in the middle of nowhere. For day to day driving, the stock heating should be fine when working - especially when you have a (stock from factory) thermostat on your engine to help the warm up times, it also diverts more air to the heating system on start up to help demisting etc and speed up the heat flow.

Call me an optimist though - many VWs do not have the heating system maintained, and as such they gained a reputation (possibly deserved when compared to modern watercooled cars) for having very bad heating.
Especially as many people remove / can't be bothered with running the original thermostat and flap arrangement in the fanhousing, for reasons which are beyond me

As my bay is used primarily for driving, rather than camping, I find the stock system is adequate (or will be when sorted properly!) For camping, I use a small electric 230v heater when the engine is not running (when heat is needed, obviously!)

 

[easy]

What engine are you fitting? if its a 1776 you would benefit from j tubes (slight increase in power etc) if its for a 1600 then you may aswell put on some NOS exchangers as they will be super nice and warm when on the move.

As has been said, if you have a heater such as a eberspacher or propex then you can make do with j tubes, as your heat is from elsewhere. 8) :wink:

 

[rustydiver]

As has been said, if you have a heater such as a eberspacher or propex then you can make do with j tubes, as your heat is from elsewhere. 8) :wink:[/quote]

Gonna sound a real numpty now. But are you not supposed to use propex while driving :? :? .

In laws got it fitted to ther non vw van :twisted: and their user manual says only use when stationary (not at traffic lights)

 

[Guest]

As has been said, if you have a heater such as a eberspacher or propex then you can make do with j tubes, as your heat is from elsewhere. 8) :wink:

Gonna sound a real numpty now. But are you not supposed to use propex while driving :? :? .

In laws got it fitted to ther non vw van :twisted: and their user manual says only use when stationary (not at traffic lights)

nope, theres nothing to stop you from using it when on the move. I thought the same thing, but apparently its safe enough and not illegal to use it while on the move. i would fit a CO detector as a precaution anyways.

 

[-tipi-]

What about as original heat exhangers close the gap between the the lower engine tin and the head, so that hot air is blown backwards. When using J-tubes, have you guys added a tin to close that gap?

 

[Haveacamper]

whichever route you decide i think you should make sure you have heat coming up to the windscreen to help demist. i didnt have any heating for a while through winter/spring and at one point had ice on the inside of the screen

 

[easy]

whichever route you decide i think you should make sure you have heat coming up to the windscreen to help demist. i didnt have any heating for a while through winter/spring and at one point had ice on the inside of the screen

know that feeling! :lol:

Its fine to use the propex on the move, just keep an eye on its sounds and fit a co2 meter as has been said. Works like a charm 8)

 

[Araon]

The likes of the webasto and ebers are designed for marine applications, even if it were moored up the movement can be quite a bit....I think youll find its more of a recommendation that gets them round the legalities of incidents being acrued to the use whilst on the move...

A co2 monitor is always a good idea especially with the exchangers as I think most of us are aware they receive minimum maintenance and maximum abuse bits of tin missing worn seals and pin holes etc... how many people have had a few funny smells in the cab...and I'm not talking about the after effects of those campsite chillied beans washed down with beer...

 

[Sittingonthedockofthe BAY]

Hi many thx its a 1600,Pete nice is fitting it for me on thursday,i will then try the original heat exchangers there not hooked up at the mo whats the best sort of piping to use....watching the ships roll in,just to watch em sail away again....