Servo connection to inlet manifold

Post by **M_Temple** » Wed Jan 23, 2008 9:01 pm

Some advice please.
I am planning to fit a servo and discs and remote reservoir (thanks Jonathan) to my refurbished, (back from the dead really!) 1969 Trav. The engine is the later 1098cc version with the dashpot breather on the side of the block and the 'top hat' filter connected into the inlet manifold.

I was about to drill and tap the manifold (off the engine of course) right next to the existing large (6-8mm hole I'd guess) hole for the 'top hat' when it occurred to me why not fit a tee piece into the existing hole with the straight section supplying the 'top hat' and the side branch connected to the servo - it points nicely across the rocker cover towards the servo as well.
Anyone done this and with what results? Anyone see any reason why it's not a good idea? Given the size of the hole I cannot see it impacting the 'pull' of the vacuum much.

Thanks

Post by **bmcecosse** » Wed Jan 23, 2008 9:10 pm

You could do this I suppose - provided your filter is working ok. No harm in trying it! You really shouldn't need a servo on a wee car like the Minor - but it's your choice of course.

Post by **MoggyTech** » Thu Jan 24, 2008 3:52 am

As BMC has pointed out the servo is not really required, the discs alone will improve the brakes greatly. Your idea will work fine, but be sure to fit a check valve between servo vacuum line and the manifold, and make sure it's fitted the correct way round. Disc upgrade alone requires no extra plumbing except for the remote fluid tank and line. Discs plus servo is a major plumbing job.

Post by **Willie** » Thu Jan 24, 2008 10:05 am

It would be better if you could replace the 'top hat' breather system with
another of the late type Minor systems as it is the most trouble prone of all. If you are going to the trouble of fitting discs then I would certainly fit a servo too.

Post by **Packedup** » Thu Jan 24, 2008 1:39 pm

Drums have a self servo action, discs don't. Hence I personally would always want to fit a servo if fitting discs.

By top hat do you mean the nasty rubber diaphragmed spring loaded valve that goes between the breather and inlet manifold? I'd be tempted to ditch that completely and use the hole in the inlet for the servo. Then plumb the crankcase breather into the carb or air filter (or, without wishing to start the arguments again, to air...). Less drilling and less complicated perishing rubber bouncy springiness to go wrong on the inlet side of things

Post by **bmcecosse** » Thu Jan 24, 2008 1:46 pm

I tend to agree with that P-up, because otherwise I suppose there is a chance that oil from the breather will find it's way into the servo.
Of course - as regular readers well know - there is another much easier way to improve Minor brakes without the hassles of fitting discs or servo!

Post by **dunketh** » Thu Jan 24, 2008 2:23 pm

Of course - as regular readers well know - there is another much easier way to improve Minor brakes without the hassles of fitting discs or servo!

Open the doors so they act as air-brakes?

Post by **southerly95** » Sun Jan 27, 2008 2:51 pm

Posted: Jan 24, 2008 - 11:05 AM

--------------------------------------------------------------------------------
Re this thread what id the later type of breather system? I thought the top hat was the later type?

It would be better if you could replace the 'top hat' breather system with
another of the late type Minor systems as it is the most trouble prone of all. If you are going to the trouble of fitting discs then I would certainly fit a servo too.

Also - DSN do a manifold adapter that looks like a thicker version of the black plastic carb/manifold spacer, not cheap though.

Post by **bmcecosse** » Sun Jan 27, 2008 5:45 pm

Top hat was kind of 'anti smog' version - popular for a while until they realised it doesn't work. Better to just breathe one of the vents into the carb - little brass pipe on the side provided. Some prefer to join the vents - I like to keep one open.

Post by **Willie** » Sun Jan 27, 2008 6:53 pm

No, the top hat system was not the final type. Since it was prone to give trouble it was changed to the system where the tappet chest now had a cylindrical oil trap on it which fed via a rubber pipe straight to the carb.
(not the air filter). You must ensure that your oil filler cap is the vented type with a wire filter inside it when you use these later systems.

Post by **M_Temple** » Sun Jan 27, 2008 7:30 pm

Again thanks for all the comments. My air filter casing (sloped housing with inlet that angles out of the base) already has a connection that looks the same size as the pipe out of the dashpot so I can pipe into it easily. It doesn't seem to be used for anything else.

BMC when you mention 'breathe one of the vents into the carb - the little brass pipe on the side provided' could you post a picture or describe more fully how you think I should do this. My engine has the cylindrical (about 80mm high by 35mm dia) dashpot with what looks like single a 1/2" or 3/8" pipe coming off the top that goes into this 'top-hat' filter that no one has a good word for. How would I pipe a 3/8" pipe into the carb? I certainly don't recall anything that size, brass or otherwise. Sorry if I'm being dumb here, but I'm new to some of the terms you 'regulars' use.
Thanks.

Post by **bmcecosse** » Sun Jan 27, 2008 9:22 pm

Hmm - don't understand your device - any chance of a picture ? I thought you said yours was connected into the manifold ? The trouble with running a breather into the air filter is - it dumps oil all over the paper element and soon clogs it up. Later SU carbs have a brass tube on one side where the breather connects. Don't thing I have a 'library' pic of it to hand - and it's dark and raining!!

Post by **bmcecosse** » Sun Jan 27, 2008 9:26 pm

Here's a pic from Minisport - the brass tube for the breather is the one sticking up at about 45 deg - not the smaller one facing.

Post by **Willie** » Mon Jan 28, 2008 9:10 am

If your car has the 'top hat' system but does NOT have the pipe on the carburettor to which you could attach the rubber pipe then you could have the much rarer sytem where the pipe from the top hat connected to the inlet manifold NOT the carb? You should not connect to the AIR
FILTER as a breather unless you fit the rocker cover with an outlet pipe and fit a SOLID oil filler cap.

Post by **Kevin** » Mon Jan 28, 2008 3:59 pm

Sorry if I'm being dumb here,

Dont worry about that, there are a few of us in that club

Post by **M_Temple** » Wed Jan 30, 2008 12:38 pm

If someone can describe 'adding photos for dummies' I will show a few pics. I have tried to decipher the instructions on the 'post reply' page and it has defeated me - and I thought I was computer literate!

Post by **Kevin** » Wed Jan 30, 2008 12:43 pm

Do you mean this posting as its what most use as a guide.
http://www.morrisminoroc.co.uk/index.ph ... pic&t=9028

Post by **bmcecosse** » Wed Jan 30, 2008 1:50 pm

You need to save your pics onto say photobucket (which is free!) - when that's done you just click on the 'IMG' version of your pic as stored in photobucket, and then paste it into the thread message. Couldn't be simpler really!

Post by **Willie** » Wed Jan 30, 2008 3:58 pm

Photobucket is a good free reliable site, just make sure that the whole
IMG address is on one line, if you carriage return in it it won't appear!

Post by **M_Temple** » Wed Jan 30, 2008 9:12 pm

Well here goes - this should be a picture of the original engine layout with the 'top-hat' connected directly to the inlet manifold- you can see what a state it was in!

There is no brass connection on the carb - I checked this afternoon.
If this works I'll post a few more angles etc.

Morris Minor Owners Club

Servo connection to inlet manifold

Servo connection to inlet manifold

breather

top hat

breathing

[pics