SaabCentral Forums banner
1 - 12 of 12 Posts

·
Registered
Joined
·
193 Posts
Discussion Starter · #1 ·
Anyone know how many metres of 4mm vacuum hose I need to replace them all on a 16v Turbo engine? It's a Lucas, if that makes any odds.

Ta.
 

·
Registered
Joined
·
3,720 Posts
Is 4mm ID or OD? If it is similar to 5/32 ID, and ALL lines are being replaced, I would recommend roughly 5M (15Ft). This would include the lines to the vacuum reservoir, and any vent control lines in the engine bay. If a turbo-might want an extra meter to make sure all lines to the dash are taken care of.
 

·
Registered
Joined
·
193 Posts
Discussion Starter · #3 ·
ID. 4mm is what Parts for Saabs sell - I think 4mm equals 5/32 inch, if my maths is correct. Thanks...
 

·
Registered
Joined
·
3,720 Posts
For the silicone lines I have installed, I have had to replace with rubber the vacuum lines that come off of the valve cover. Engine oil degrades silicone and caused splitting on those lines. Otherwise it has worked great on my 87 N/A. Also makes it easy to find them since they are not black on this car.
 

·
Registered
Joined
·
279 Posts
5m to 6m should be sufficient. Buying a couple of metres more probably wont go astray, I broke one solid vacuum line accidentally and used about 1.2m (inlet manifold to left front wing) to replace it.
 

·
Registered
Joined
·
1,320 Posts
For the silicone lines I have installed, I have had to replace with rubber the vacuum lines that come off of the valve cover. Engine oil degrades silicone and caused splitting on those lines. Otherwise it has worked great on my 87 N/A. Also makes it easy to find them since they are not black on this car.
That is good to know. A friend has been using silicone hoses in his Porsche 944 for the last 5 years and said he is yet to replace any piece. We will see.

That's very much the plan. Now I just need to decide which colour...
I am getting a bright colour (yellow in my case) for the very same reason crwchf01 mentioned.
 

·
Registered
Joined
·
10,081 Posts
Anyone know how many metres of 4mm vacuum hose I need to replace them all on a 16v Turbo engine? It's a Lucas, if that makes any odds.
I bought six metres, and had plenty left. Did I have a whole metre left? Dunno. Definitely didn't have two metres left, though. That included the pipe across the windscreen base to the vac bottle, though.
 

·
Registered
Joined
·
193 Posts
Discussion Starter · #10 ·
Thanks chaps. Have ordered 6 metres in blue - was gonna stick with black, then I realised that if I go coloured, I'll be able to tell which ones I have and haven't done!
 

·
Registered
Joined
·
3,601 Posts
For the silicone lines I have installed, I have had to replace with rubber the vacuum lines that come off of the valve cover. Engine oil degrades silicone and caused splitting on those lines. Otherwise it has worked great on my 87 N/A. Also makes it easy to find them since they are not black on this car.
It degrades rubber hose too. To use silicone hose for conveying fuel/oil vapours such as connections to/from the intake manifold, particularly the crankcase vent hoses, the silicone hose has to be a special type called flouro-lined silicone.

It is possible to find, but I discovered the the KTM Hardparts orange silicone hose sold by a heap of people on Ebay for motorcycle engine use is exactly right for our Saab engines and it is the flouro-lined type (which is why it tends to be more expensive that the really cheap [Chinese?] standard silicone hose).

Grab some of that. I have used cheap silicone hose for other things like the lines to/from the vacuum tank, and also to replace the rubber hose between the windscreen washer reservoir and the jets on the bonnet. Normal silicone is just fine for carrying water (but I would not use larger diameter sizes for a coolant application unless it's multi-layered with good nylon re-inforcement between the layers).

Craig.
 
1 - 12 of 12 Posts
Top