free hit
counters
S4s turbo coolant ports -thread size? - Induction/Turbo/Chargecooler/Manifold/Exhaust - The Lotus Forums Jump to content
Chillidoggy

S4s turbo coolant ports -thread size?

Recommended Posts

Despite them supplying me with the new turbo, the laughingly-termed "customer service department" at Fawlty Turbos had, as expected, "errrr......no idea mate" as what the female thread in in the turbo body might be.

Does anyone know, please?

Share this post


Link to post
Share on other sites

Upgrade today to remove Google ads and support TLF.

From memory I think they are quite big but not sure if that's metric or imperial. HTH.

Trevor.

Share this post


Link to post
Share on other sites

Is the bolt/stud thread size not shown on the parts diagrams (Deroure site etc)? They often are...

Share this post


Link to post
Share on other sites

No, there's no size listed I can see, and I have searched the web extensively, but come up with all kinds of different answers.

The brass fittings look unique, I've never seen anything like them, only shorter block elbows, but the female end fittings are 5/8" UNF, 18 TPI, and the male end is a taper.

I suspect it's 3/8" NPT, but I don't know.

Share this post


Link to post
Share on other sites

I don't remember the size, but I replaced them with parts from an American home and garden store... So they are definitely not metric. I think sailorbob is correct.

Share this post


Link to post
Share on other sites

3/8" NPT. The other end is a standard flare nut.

Edited by sanj

Share this post


Link to post
Share on other sites

So the turbo body is 3/8" NP, and the brass fitting is 3/8" NPT? Or are they both NPT? I suppose if I get a straight fitting , I could check that.

NPT dies are available, so I could conceivably shorten the brass fitting, and recut the thread if I'm careful.

Share this post


Link to post
Share on other sites

The female threads in the turbo and the mating male threads on the brass fitting are the same, either NPT or NPTF. If it's damage at the male end of the brass fitting you're dealing with there's no reason I can think of to stop you re-threading it. There is a limit on how short you can make it, however.

Share this post


Link to post
Share on other sites

Having done some more thinking, and a bit more research, I've come to the conclusion that the original fitting has to be replaced. They are definitely 3/8" NPT, in case anyone is interested. Or at least they are on my turbo/fitting.

I'm not going to bother shortening and rethreading the brass fitting, it's too much of a pain, because I'd have to machine a taper on the shortened fitting, and to do that I'd have to set it up in a 4-jaw chuck, plus order an NPT die, or set the lathe to thread cut, and it's getting a bit time-consuming.

So I've found, and ordered up, a 90 degree 3/8" NPT elbow which has a 3/8" hose tail. I've ordered some new 3/8" flexy pipe, and hopefully that should solve my problem.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×