14 replies to this topic

[Kevybmini]

Hi,

 

I have just put my engine back together and I wondering if the cam timing has not been set correctly, seem to run out of steam at about 5,000 revs.

 

Also seems to be a lot of fumes / vapour coming out of the transfer case breather which it didn’t before. Same block / pistons / head as before taking apart due to oil leaks. So replaced the cam during re-build with MED belt drive.

 

I’m thinking the timing needs advancing, what your thoughts, 
 

1310 A+

MED RS Cam Shaft 1250 - 6500 

Twin 1 1/2 HS4

 

[KTS]

how did you set the cam timing when you installed it ?

[imack]

Did you previously have a breather on the timing cover as well as the transfer case?
Is it the same cam as before?

Edited by imack, 16 March 2024 - 03:00 PM.

[Kevybmini]

Well I thought I had set it correctly as per usual with DTI ect. Previously had a breather on the chain cover but not now. Just the transfer case.

[imack]

Maybe you need more breathers, not sure that just the transfer case one is adequate for a 1275+ cc engine.
This obviously won't account for lack of top end though.
So is the cam itself the same one as before or have you changed it?
If it's a different cam to before it will need a fresh RR session.

[Kevybmini]

New cam, think I’ve sorted sorted it to a point. Balanced the carbs and colourtuned it. Maybe I’ve been driving my tesla too muc - there is a lot coming out of the breather so need to do something with those fumes . Any suggestions as there is nothing on the manifold to connect it as there is a servo. 

[Spider]

A common cause of lots of fumes from the crank case is the rings aren't sealing and a common cause for that is a worn bore.

[Cooperman]

Get the engine fully warm and set the tick over to around 1000 rpm.

Then remove the oil filler cap. If it's 'puffing' smoke out you probably have worn bores/rings. If so, do a 'leakdown' test or get one done.

[Kevybmini]

Ok, I did a compression test and all cylinders were 180 psi 

[kiwi topcat]

hi I also have a 1310 A 

when i got this going i had excess fumes and breather on flywheel end and off the tappet cover, you could see the fumes coming out the breathers.

 

i have since added a breather to the timing cover (small elbow bolted to the cover)  plumbed via rocker cover then to a catch can also another breather off the flywheel end also to the catch can.

 

after about 3000Km the fumes have reduced heaps.

[Kevybmini]

Cheers, for the reply. I was wondering if I could plumb the breather pipe into the servo line. Some say it also needs a valve but it’s not very clear.

[Lplus]

Cheers, for the reply. I was wondering if I could plumb the breather pipe into the servo line. Some say it also needs a valve but it’s not very clear.

It needs a valve.  Never plumb the breather direct to the servo port.

[Kevybmini]

What type of valve 

[Lplus]

I suggest part no 13H5191 available from minispares would do the job, that being the valve used for the early closed circuit ventilation systems on twin carb mini setups which fed into the manifold itself.  It prevents full manifold vacuum being applied to the crankcase.

 

That said, the rest of the breather system needs to be compatible.  Presumably your HS4 carbs don't have breather pipes in the main carb bodies?

[Kevybmini]

No, the manifold only has brake servo banjo