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mk1 square four . oil issues

Posted: Sun Feb 02, 2020 10:13 pm
by GuyWalton
I have a suspicion that there is too much oil going to the rocker box . I have a morgo oil pump fitted which has a strong return . I have recently rebored and fitted new pistons but it is just as smokey as it was before . There are new valve guides fitted but there is oil on the piston crowns when looking in the plug holes . Starts and runs well just the smoke . I know it still needs running in but I think I have an over oiling issue . Im thinking of changing the banjo in the head to restrict the oil . Whats your thoughts on this .
The pistons were renewed because of damage to the crowns which looked like corrosion in the alloy I was never happy with them .

Re: mk1 square four . oil issues

Posted: Sun Feb 02, 2020 10:36 pm
by alan.moore
Don't know much about Squares but Simon did a bit on rockerbox oil feeds on his website, maybe something there to point you in the right direction?

http://ariel-square-four.blogspot.com/2 ... e-mod.html

Cheers
Alan

Re: mk1 square four . oil issues

Posted: Sun Feb 02, 2020 10:47 pm
by GuyWalton
alan.moore wrote:Don't know much about Squares but Simon did a bit on rockerbox oil feeds on his website, maybe something there to point you in the right direction?

http://ariel-square-four.blogspot.com/2 ... e-mod.html

Cheers
Alan
Yes I have read that and ive tried to message Simon but its still in out box so looks like his message box is full . Im going to disconnect the oil to rocker box supply and run it without to see if it still smokes that will prove it . Tomorrow will do though .

Re: mk1 square four . oil issues

Posted: Sun Feb 02, 2020 11:57 pm
by will_curry
Guy,

The stud in the crankcase to which the rocker feed and oil gauge are connected has a smaller
hole than 'usual' to restrict the flow - the subject of another thread on this site.

Even with the correct stud the Morgo over-oiled the top of my Mk 1. In the end I fitted a joggle
wire.

Some care is necessary if the oil feed is reduced as oil from the 'box lubricates the cam lobes too.

Re: mk1 square four . oil issues

Posted: Mon Feb 03, 2020 12:41 am
by Simon.Gardiner
GuyWalton wrote: ..ive tried to message Simon but its still in out box so looks like his message box is full.
As I understand it the messages stay showing in your out box until they're actually opened/read by the recipient....

SG

Re: mk1 square four . oil issues

Posted: Mon Feb 03, 2020 7:19 am
by camstevens
Hi Guy
I have the same issues with my MK1: totally new engine that runs well but still blows smoke after 300 miles. Two things have made a positive change;
1. the crankcase oil feed banjo stud Will describes was not correct, and using a stud with a smaller restrictor orifice reduced over-oiling and head leaks
2. the crankcase breather banjo stud orifices were way too small....the engine was simply unable to breathe .....I opened out the banjo stud and this made an immediate improvement. The crankcase must have been over-pressurising

However, the engine still puffs, and I am told to be patient up to 1000 miles and let the engine run in ( and take a view then). The current smoking suggests oil is also coming from the bottom end still, not just the top. Also, I get oil pooling on pistons....I think that's the nature of the beast and the only way to avoid this is to fit seals to the guides....I may do this in time.

Regards
Cam

Re: mk1 square four . oil issues

Posted: Mon Feb 03, 2020 7:25 am
by camstevens
will_curry wrote:Guy,

The stud in the crankcase to which the rocker feed and oil gauge are connected has a smaller
hole than 'usual' to restrict the flow - the subject of another thread on this site.

Even with the correct stud the Morgo over-oiled the top of my Mk 1. In the end I fitted a joggle
wire.

Some care is necessary if the oil feed is reduced as oil from the 'box lubricates the cam lobes too.

Hi Will
What is the size of orifice did you use in the oil feed stud? I think mine is still original.

Camp

Re: mk1 square four . oil issues

Posted: Mon Feb 03, 2020 8:07 am
by GuyWalton
will_curry wrote:Guy,

The stud in the crankcase to which the rocker feed and oil gauge are connected has a smaller
hole than 'usual' to restrict the flow - the subject of another thread on this site.

Even with the correct stud the Morgo over-oiled the top of my Mk 1. In the end I fitted a joggle
wire.

Some care is necessary if the oil feed is reduced as oil from the 'box lubricates the cam lobes too.
Will . What is a. " Joggle Wire "
.

Re: mk1 square four . oil issues

Posted: Mon Feb 03, 2020 8:09 am
by GuyWalton
camstevens wrote:
will_curry wrote:Guy,

The stud in the crankcase to which the rocker feed and oil gauge are connected has a smaller
hole than 'usual' to restrict the flow - the subject of another thread on this site.

Even with the correct stud the Morgo over-oiled the top of my Mk 1. In the end I fitted a joggle
wire.

Some care is necessary if the oil feed is reduced as oil from the 'box lubricates the cam lobes too.

Hi Will
What is the size of orifice did you use in the oil feed stud? I think mine is still original.

Camp
As is mine . More to it than I thought .

Can is one exhaust worse than the other as mine seems to be only the left .

Re: mk1 square four . oil issues

Posted: Mon Feb 03, 2020 8:31 am
by camstevens
Guy
I'm also curious as to what a Joggle Wire is. I was thinking of fitting a needle valve in the rocker feed line, but as Simon alludes to.....starving the cam lobes would be a worse outcome. Perhaps a restrictor stud with reduced orifices is a safer starting point.

Cam