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Re: HS6 rebuilds,things to do and don,t?

Posted: Fri Jan 16, 2015 2:32 am
by tony
Sounds like waxstat set up to me, with the clip. Can you post a pic ?
Tony.

Re: HS6 rebuilds,things to do and don,t?

Posted: Fri Jan 16, 2015 5:00 pm
by Clifford Pope
Could it be a converted ex-waxstat, using penny washers?

Re: HS6 rebuilds,things to do and don,t?

Posted: Fri Jan 16, 2015 5:06 pm
by johnnydog
Very easy to tell the difference between standard jets and wax stats - the standard jets have red tips, and the wax stats look like a top hat upside down :?:

Re: HS6 rebuilds,things to do and don,t?

Posted: Fri Jan 16, 2015 5:23 pm
by sahtuning2000
All rebuilt with new parts and the jets are normal ones,hopefully i get a chance to refit them tommorrow and fingers crossed it all runs fine,got all new breather hoses to fit aswell.
Fitted standard flat throttle discs and BFZ needles,new jets,float valves etc and all seems good,the test will be if it starts!
I set the jets at level with the bridge and turned down 2 whole turns on etc carb,so that should be a base to start.

Re: HS6 rebuilds,things to do and don,t?

Posted: Fri Jan 16, 2015 11:05 pm
by TedTaylor
Thanks for the update - good luck tomorrow!

MUT

Re: HS6 rebuilds,things to do and don,t?

Posted: Sat Jan 17, 2015 8:55 am
by racer
the reason for using atf in the carb dashpots is that the "viscosity" remains the same no matter what the temp is under the bonnet, so giving a more consistant amount of resistance to lift, unlike oil.
hope this info is of some help

Re: HS6 rebuilds,things to do and don,t?

Posted: Sat Jan 17, 2015 10:56 am
by David Withers
racer wrote:the reason for using atf in the carb dashpots is that the "viscosity" remains the same no matter what the temp is under the bonnet, so giving a more consistant amount of resistance to lift, unlike oil.
hope this info is of some help
I found it difficult to understand why an ATF wouldn't change viscosity with change of temperature so did a bit of browsing...

From Mobil's data sheet for their Delvac Synthetic ATF:
Viscosity, ASTM D 445
cSt @ 40º C 39
cSt @ 100º C 7.3

From Redline's data sheet for their Racing ATF:
Vis @ 100°C, cSt 10
Vis @ 40°C, cSt 53.7

I've never had a problem using engine oil in my 55 years experience with SU carburettors, whether it be the straight 30 that they specified before the days of multigrade oil or the 20W/50 specified in later years. I experimented with alternatives back in the days when I wanted to get faster acceleration from whatever car I had at the time, but none seemed to work as well as the correct engine oil.

Re: HS6 rebuilds,things to do and don,t?

Posted: Sat Jan 17, 2015 7:14 pm
by sahtuning2000
Fitted the carbs today and it started up perfectly and ran lovely on fast idle with choke out and after a couple of minor adjustments it ran spot on,really pleased,BUT then it wouldn,t start,read my new post!

Re: HS6 rebuilds,things to do and don,t?

Posted: Sun Jan 18, 2015 10:25 am
by Clifford Pope
David Withers wrote:
racer wrote:
I found it difficult to understand why an ATF wouldn't change viscosity with change of temperature

Even multigrade oil still gets thinner with temperature, just not as much so as a straight oil would.

Is there actually any liquid that doesn't get thinner with temperature? Molten sugar perhaps, as it turns into jam?
:)

Re: HS6 rebuilds,things to do and don,t?

Posted: Fri Mar 17, 2017 11:01 am
by torque2me
David Withers wrote:
racer wrote:the reason for using atf in the carb dashpots is that the "viscosity" remains the same no matter what the temp is under the bonnet, so giving a more consistant amount of resistance to lift, unlike oil.
hope this info is of some help
I found it difficult to understand why an ATF wouldn't change viscosity with change of temperature so did a bit of browsing...

From Mobil's data sheet for their Delvac Synthetic ATF:
Viscosity, ASTM D 445
cSt @ 40º C 39
cSt @ 100º C 7.3

From Redline's data sheet for their Racing ATF:
Vis @ 100°C, cSt 10
Vis @ 40°C, cSt 53.7

I've never had a problem using engine oil in my 55 years experience with SU carburettors, whether it be the straight 30 that they specified before the days of multigrade oil or the 20W/50 specified in later years. I experimented with alternatives back in the days when I wanted to get faster acceleration from whatever car I had at the time, but none seemed to work as well as the correct engine oil.
Dave, thanks for clarifying the ATF characteristics; even if only a couple of bods race. Do you know if earlier ATF formulations were based on mineral? I've always used SAE30 (which is still readily available - lawn mowers and the like) but have used 20w50 also.

Kev