Page 1 of 1

10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 9:32 am
by Rob Ripley
Here's a pic of the tank of a 102 I'm trying to sell ... what do I tell the buyer, if there is any, about the fuel mixture ?
and a pic of the tank of another.....

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 9:39 am
by Hugz
Depends which motor it is going on, SD is 8 to 1 or 10 to 1 on the later 102's except for ED's. Can I have first refusal please....

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 9:45 am
by Rob Ripley
G'day Hugz, the old label is the 102 I''m trying to sell (AD860), if it does not go by the weekend I'll pull it. Check out Gumtree.

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 9:47 am
by Hugz
Yes, a very early AD with brass tank and bayonet cap...? Thought you were selling tank only :lol:

Edit: AC and somebody has nicked the clutch, probably the same guy that is selling the $500 AD with clutch. Pop a plain cover on the mag as the lettered ones came later (and are more sought after) If somebody bought both of them they would have two nice early AD/AC's with two rare tanks... Adrian?

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 2:42 pm
by headdownarseup
I'd err on the side of caution with these older "old dears" and stick with 8:1
Not such a bad thing to have a healthy smoking habit on some of these.
10:1 with most 102's after mid 1960's onwards.

interesting to see if anyone will be recreating the older 8:1 fuel decal in the future?

p.s does AD860 have the hex head core plugs in the cylinder? (good if it does as this will be the correct cylinder for it)

jon

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 3:39 pm
by Hugz
Interestingly that the tank with 8 :1 has screw cap so the AD/AC did first come out of Seagull with 8:1 unless it is off a D or C :?

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 7:08 pm
by phil
Seems to me that the imperial measurement gives 10:1, 16oz. (1pint) to 160oz. .(1gallon) = 10:1

Also 10:1 is not too smoky unless you running it too rich or with too cold a plug, which is the case with almost every Seagull I've bought, all carboned up, unless it's being run many hours a day at close to full throttle, I my opinion a D16 is too cold, needs a D21.

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 7:35 pm
by Niander101
Surely 10/1 would be fine.

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 8:39 pm
by Charles uk
We are talking "Imperial Pint" 20 oz. = 8 : 1, remember these are imperial motors.

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 9:09 pm
by headdownarseup
10:1 WILL be fine, (metric or imperial) most 102's run quite happily at that but as Phil has pointed out the vast majority of seagulls tend to need a hotter plug. (or a long run at high revs)
Tough old birds these 102's you know!
With a lot of my 102's i dont get to use them as often as i'd like so i opt for 8:1 and rev'em hard (just keeps things nicely lubed up for when they're sat on the rack for ages)
If i had the chance to actually use my motors everyday i might even consider a slightly leaner mix of say between 12/15:1 to see how things go.

jon

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 10:25 pm
by Charles uk
Why would you put a Seagull that has done 65 years work, hard or not, with bearings that might be showing their age, on a low lube diet.

This in my opinion might be the time, to move it onto a slightly higher fat diet.

The lubricant this motor was brought up on, was in many cases, used 30 weight engine oil, oil in the late 40's early 50's was a scarce commodity & rationed.

Re: 10:1, 8:1, or wot ?

Posted: Fri Apr 10, 2015 11:19 pm
by Adrian Dale
On all my old motors FV's, AD102, LS etc. I use 8 to1 no less; when first testing after a strip down, I go even higher 6to1

For the long distance runs for the Centuries, 40+ and silver centuries I go with 10 to 1

I have never had a problem with carbon nor difficulty in starting. The LS pictured is on a longish run of 4 hours on a 8:1 mix note very little smoke is evident in the photo.

Again apologies for the skewed picture. I have more trouble with loading photos than with oil ratios!!

AJ

Re: 10:1, 8:1, or wot ?

Posted: Sat Apr 11, 2015 1:20 am
by Rob Ripley
AC860 before assembly and side view