damper oil

[cadetchris]

decided to improve Primrose's dampers with the addition of SAE 30 or 40 oil into them, but from where does on get it from?

i have tried halfrauds but i just get junk like 10w and other "w" related stuff and nothing with an SAE rating. any ideas?

[taupe]

Hi

Just type sae 30 into ebay you will see lots there and a clue as to what shops to try, its nearly all for lawnmower engines or motorcycle forks

Taupe

[bmcecosse]

Tesco garden section has SAE 30 in a handy small pack. SAE 40 from a motorcycle shop, probably. Don't be fobbed off with 'fork oil'.........

[cadetchris]

got some sae 30 lawmower oil from B&Q, bit of a faff to empty the dampers and then refill. but good god the difference is noticable in just pushing the car up and down

[bmcecosse]

Of course it is !!

[horrace]

whats the difference? how does the viscosity affect it? not sure what ive got in mine but ride is hard

[bmcecosse]

'Hard' ride is usually caused by the suspension hitting the bump stops. Is there good clearance between stops and chassis ? Even with more viscous oil in the dampers - the Minor suspension is still nicely 'compliant' - it just doesn't bounce about like a super ball quite so much!

[horrace]

just to confirm this is the front dampers we are talking about, dont saloons and travellers have rear dampers aswell?
i have a pick up so have shocks on the back, which afre not really adjustable, ive proably got 3 in 1 in the front dampers

[bmcecosse]

Well - 3 in 1 is very definitely far too low viscosity ('thin').

[horrace]

som how would that affect it?

[chrisryder]

pour some oil through a funnel. then pour some water through a funnel.

come back and tell me which one empties quickest.

[bmcecosse]

The dampers work by squirting oil through tiny calibrated holes in the valves. Low viscosity ('thin') oil squirts through easily - high viscosity ('thick') oil less so - but of course, there are reliefs built in, so there is a limit to how much harder you can make the damper work, unless you also beef-up the relief valve setting of course.

[horrace]

thank you bmecosse for your useful explanation of how it works, i had no idea.
and chris your glib comments do nothing to help or educate me so dont bother next time

[bmcecosse]

I'm sure Chris meant well with his explanation - it amounts to the same thing........

[chrisryder]

sorry for the glib comments. won't happen again.

[chrisryder]

hang on, it wasn't a glib comment.

it was a practical explaination of how viscosity affects flow.

...albeit portrayed in a glib way.

[horrace]

apology accepted

[Dean Moriarty]

I was looking to top up my dampers and came across this thread.
I have 0/30 oil for my Honda. I'm assuming the 30 is the SAE rating so will this be ok to use?
Is there a facility to drain the old oil in the damper before topping up but without removing the damper from the car?
I'm assuming mixing the oils be a problem?

Thanks

[cadetchris]

there is the drain plug at the bottom, if you whip that off, place a suitable jar underneath and bounce the car up and down a bit, it should flush the old oil out.
refill and bounce a bit more to get the air bubbles out and enjoy the new stiffness of the damper

[bmcecosse]

NO!!! 0/30 oil is effectively 0 SAE - so will be worse than useless in the dampers! Buy a small tin of SAE 30 from Tesco - it's not expensive.