View Full Version : Stromberg Dash Pot Oil

09-13-2004, 04:51 PM
Hello! I was wondering if you folks had any suggestions on what type of oil I should use in my 1965 TR4 Stomberberg carbs. In my old TR6's, I used to use ATF, but someone told me that using ATF is a not good. I bought my TR4 from the original owner, and he said he used 3 in 1 oil, which I found hard to believe. Do any of you folks have any suggestions on what type of oil should be used in Stromberg dash pots?

09-13-2004, 05:31 PM
You're going to get a wide range of opinions on this one. My Triumph mechanic, who's very experienced with these cars, swears by good old 3-in-1 machine oil. I've used it in two GT6s and it works great.

Everyone else, please chime in!!

09-13-2004, 05:33 PM
use the same oil you use in your engine, and DON'T overfill it. I believe the dashpot plug should indicate hesitation when pushed down.....about 1/4" above the carb neck.

09-13-2004, 06:30 PM
I use gun oil. Friend of mine uses engine oil. From what I know pretty much any quality oil will work.

09-14-2004, 08:00 AM
I've been using 20 weight oil in my 65 TR4 with good results out of my Strombergs. You have me thinking we should both try different weights and note the results. The heavier the oil, the slower the pistons rise in the carbs and hence a richer mixture. That would equate to a quicker response for sport driving. A thinner oil is recommended for street use I'm told. Someone please verify this if you could.

09-14-2004, 11:57 AM
you folks have been great! Thanks for the all the suggestions!

09-14-2004, 01:31 PM
The reason people give all types of answers is that there are all types of correct answers.

The type of fluid you use in Strombergs and SUs depends on many different criteria. The first is the condition of the carbs themselves. If the carbs are strong, and recently rebuilt, 20wt is generally what the manuals specify. If your carbs are good, but old, ATF is a typical good substitute.

If you drive your car in the cold, going for a thinner oil is fine. If you drive in the heat of summer, a thicker oil is fine.

3-in-1 is very, very, very thin oil, and many times will result in fluttering.

You should also consider if you are using stock needles and ignition tuning. How you have your car set-up will indicate if you want those pistons to come up faster or slower.

I've used ATF, 20wt, Marvel Mystery Oil, 40wt, and even 50wt in different carbs. I use ATF now, and it works great for my car in the current situation.

09-14-2004, 03:18 PM
i don't think any kind of transmission fluid should be used in the carbs when the manual specifies regular oil. You could just get the dashpot oil for Strombergs that is marketed by Victoria British, and call it a done deal.

09-14-2004, 05:34 PM
The only problem with the actual dashpot-spec oil is that if your carbs are worn, or needles are different, the dashpot oil tends to be way too thin, and you can get fluttering.

09-14-2004, 05:44 PM
what about 90weight gear oil?

09-14-2004, 06:12 PM
I've had carbs that I had to use a different weight oil in the front and rear to get them to operate the same!
Steve, I think 90 wt. would be a little overkill. You would probably have to hook the throttle cable directly to the piston to get it to move at all. /ubbthreads/images/graemlins/grin.gif

09-15-2004, 05:49 AM
My MGB manual recomends 20w50 for the z-s carb

Geo Hahn
09-16-2004, 03:37 PM
My MGB manual recomends 20w50 for the z-s carb

[/ QUOTE ]

That is what I use just because that is what I put in the engine and am driving in mostly hot and never cold conditions.

The 90 wt gear oil would be about the same weight as 20w50 (engine and gear oils measured differently) but would have a sulfur component that I would be wary of.

09-16-2004, 08:42 PM
The owners manual suggests that you use 10w 30.

i use this in my TR6 and it works perfectly