J tubes

Early Bay Forum

Help Support Early Bay Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

thejinx

Well-known member
Supporting Member
Joined
Mar 30, 2011
Messages
1,559
Reaction score
73
Location
swansea
been looking at my engine and noticed some holes appearing in my Heat Exchangers. The question is
Can I weld them? (massive novice on welder)
Should i fit J Tubes? I have heard you can get exhaust gas back into the cab of vehicle

My heating isn't working something i just didn't do when i put the engine in 2 years ago as a complete novice. I am now much more competent and prepared to work on the engine. I have been looking on parts emporium etc to possibly buy heat exchangers and sort heating out.

I know having or not having heating is up to me but just want thoughts on J tubes etc. At the moment i have two Nitrile gloves over the vents in the dash which inflate and deflate depending on how fast i am going. I think they are cool she doesn't.
 
I only use my van in spring summer so binned the exchangers and went with jtubes. Worked out fine. You can block the under rear seat heater pipes with red bull can botttoms cut off and a jubilee clip. Perfect fit
 
I thought the dash vents were only for fresh air through the vent. on the front. Just to please your young lady, you could take the grill off and wack a couple of layers of cling film over the vent openings then put the grill back on and that'll shut Down excess front air ventilation and it might even please her :shock: yes right!

Ozziedog,,,,,,, must stop dreaming, must stop,, ,,, :mrgreen:
 
I thought that was the case. I also looked into a possible uncoupling of a tube somewhere. Anyway got a bit of time now as I am lucky to have a big garage in work and the boss is happy my van sits in there. She enjoyed our trip away trying to get her to sign up for a VW show. Bristol probably. Not to far and sounds good. See how the winter engine rebuild goes. Got a dodgy thread on a spark plug and one of the heat riders is blocked. Also a bit of wiring needs renewal.
 
thejinx said:
I thought that was the case. I also looked into a possible uncoupling of a tube somewhere. Anyway got a bit of time now as I am lucky to have a big garage in work and the boss is happy my van sits in there. She enjoyed our trip away trying to get her to sign up for a VW show. Bristol probably. Not to far and sounds good. See how the winter engine rebuild goes. Got a dodgy thread on a spark plug and one of the heat riders is blocked. Also a bit of wiring needs renewal.

Sounds like that is just about how they came out of the factory when they was new. Seriously with the vents, there is a bit of foam goes around each flap inside of the grill, easy enough to fix with sticky back foam draughty proofy strip Nd that's what I did, but as soon as it gets to this time of year I whip the grill off and cling film all over inside the grill then pop the grill back on and nobody would know but it'll be warmer.

Ozziedog,,,,,,,, them ladies does like being warm don't they :mrgreen:
 
I'm definitely trying that with the vents! Potential adaptation- if you hold a condom out of the window of a car at about 35-40MPH, it'll expand until it's 2ft wide and about 4ft long. Just a thought....
J-tubes/heat exchangers... There's nothing wrong with J-tubes, they're fine as exhausts, if you want to do a decent job of the conversion you'd make sure the under-cylinder tinware is boxed off a bit (not at the rear of the enging/car, on the left/right) to create the same situation as if you were using heat exchangers.
Don't throw your heat exchangers away- they're an aluminium core, so that doesn't rot. they have steel tubes fitted into them & crimped- they can rot, but replacement bits could be fabricated- and the outer steel jacket can be welded time & time again, it's only 1.2mm ish steel. The core is the good bit- the replacement ones don't have as many fins, as you've probably heard before.
 
Happystamps said:
I'm definitely trying that with the vents! Potential adaptation- if you hold a condom out of the window of a car at about 35-40MPH, it'll expand until it's 2ft wide and about 4ft long. Just a thought....
J-tubes/heat exchangers... There's nothing wrong with J-tubes, they're fine as exhausts, if you want to do a decent job of the conversion you'd make sure the under-cylinder tinware is boxed off a bit (not at the rear of the enging/car, on the left/right) to create the same situation as if you were using heat exchangers.
Don't throw your heat exchangers away- they're an aluminium core, so that doesn't rot. they have steel tubes fitted into them & crimped- they can rot, but replacement bits could be fabricated- and the outer steel jacket can be welded time & time again, it's only 1.2mm ish steel. The core is the good bit- the replacement ones don't have as many fins, as you've probably heard before.


I know we’re mates and all that bollox, but Simon HS you are wired up completely wrong and NO! Putting a relay in will not help because your wonky bits has been soldered :shock: :( :msn4:
Now then version two consists of a full length temporary bulkhead behind the cab seats made of clear plastic gaffer taped to the bodywork. One this will cut down on droughts and two the maths will work nicely as in increase the heat supplied or decrease the area to be heated with the same amount of heat. Works, costs next to nuffink, and can be repaired or replaced with hardly any effort whatsonever !

Ozziedog,,,,,,,,, we likes warmerdunnus! :mrgreen:
 
For me, Its worth spending a bit of time and energy to get the heating working nicely. Extends the camping season, and makes trips out much more pleasant. It's pretty straightforward - put some cheep exchangers on, get the heater cables moving and then and follow the pipework to the front checking for holes. The most challenging part of your exercise is taking the old exchangers off - the rest is simple.
 
As the heat and air-flow into the cabin from Air Cooled engines is not that great, my plan has always been to run J Tubes, then install an Eberspacher heater for heat and ventilation to the front cab / windscreen / windows.

Although, I have not done it yet, so I don't know how well it works. :lol: :roll:
 
Strangely out of all the parts I took off my bus, then somehow lost, the J Tubes have been good and not moved! :lol:
 
cunning plan said:
As the heat and air-flow into the cabin from Air Cooled engines is not that great, my plan has always been to run J Tubes, then install an Eberspacher heater for heat and ventilation to the front cab / windscreen / windows.

Although, I have not done it yet, so I don't know how well it works. [emoji38] :roll:
My '72 1600 has amazing stock heating. It works well with plenty of heat and air flow when correctly assembled and not holed.
Why get rid of the free heating you already have and spend a fortune on a separate heater, which takes up space and more fuel? Summer mornings can be cold and let's not forget that the heater demists the windscreen too.
If you look around heat exchangers come up second hand and also in bundle offers from big VW parts suppliers.

Sent from my SM-A320FL using Tapatalk

 
cunning plan said:
As the heat and air-flow into the cabin from Air Cooled engines is not that great, my plan has always been to run J Tubes, then install an Eberspacher heater for heat and ventilation to the front cab / windscreen / windows.

Although, I have not done it yet, so I don't know how well it works. :lol: :roll:

You need to sort the original heating system out properly.
Mine got too hot with the heat exchangers wide open, it melted the rev counter pod on the dash.
 

Latest posts

Top