Question about AH 3000 carb damper oil

[SkinnedKnuckles]

Hi there all. I have a TR6 fitted with triple ZS carbs. The Book says use 20 wt oil in the dampers. Of course, that's for dual carbs. I started wondering if maybe with a triple configuration a different viscosity would be recommended or work better. Yes - I've played around with everything from straight 50wt to 0w-30 - with some differences, but not much. I was curious, so why not ask AH 3000 owners. Yeah - different carbs, but same principle, right? So what do you guys use?

 

[Keoke]

"Carb Damper Oil"


What do you guys use for "Carb Damper Oil?

Transmission Fluid--Fwiw--Keoke--

 

[SkinnedKnuckles]

Oh brother... Yep - used ATF. It's usually either 0w-20 or 5w-20, depending on what type. Not the same as straight weight, but close. I'm going to try 15 wt oil (air tool oil). What I'm really asking is what was the viscosity originally called for in an AH 3000.

 

[Bob_Spidell]

... What I'm really asking is what was the viscosity originally called for in an AH 3000.

20W is 'book' for Healey SUs as well ('3-In-1 Oil' is 20W). If you get a little hesitation or stumble on acceleration--and you're sure it's not ignition-related--a thicker oil might help.

 

[AUSMHLY]

Hello Brent,

Are you not happy with using dashpot oil?

 

[Keoke]

Hello Brent,

Are you not happy with using dashpot oil?

Nope!!! this does not make me happy:

DASHPOT OIL, $7.75 -----Keoke---

 

[SkinnedKnuckles]

The 3-in-1 was about $3. Note: if you want 20 wt 3-in-1, get the electric motor version that's marked 20 wt. I think the "normal" is 10, maybe 15 wt. I had some 15 wt air tool oil laying around, so put it to use.

Thanks for the info, btw, See ya on the road (if you guys drive those things) :thumbsup:

 

[Ed_K]

I use marvel mystery oil most of the time but automatic transmission fluid seems to work almost as well.
.... The price is right on either of these options ....
Ed

 

[AUSMHLY]

I started wondering if maybe with a triple configuration a different viscosity would be recommended or work better. Yes - I've played around with everything from straight 50wt to 0w-30 - with some differences, but not much. I was curious, so why not ask AH 3000 owners. Yeah - different carbs, but same principle, right? So what do you guys use?

From the last few replies, this topic seems to have shifted to what's the cheapest oil. I don't think that's answering the question.

Price aside, have you tried the SU oil Moss sells, the dashpot oil?

Did in not work to your satisfaction with your set-up and that's why your searching for something else?

Does anyone know what viscosity the SU dashpot oil is?

 

[Keoke]

Price aside, have you tried the SU oil Moss sells, the dashpot oil?

NOPE!!! couldn"t afford it.----Keoke-- :laugh:


-----------------------------

 

[SkinnedKnuckles]

An aside - I wanted one of the big Healey's 20 years ago, but the price then was around $20k for something that needed even more sunk into it. Since I already had the TR6 that extra $$ went to enhancements. I see a 3000 once - twice a year. I love 'em.

I've never tried authentic ZENITH dashpot oil. Can't see how it's any better. With the later ZS carbs some oil is lost each time the needle is adjusted because the damper is removed, a tool is put in and removed, so a top-up is always needed. At $8 a pop for a small bottle of straight wt oil, why?

It's not a question of price, what I'm trying to determine where the best trade-off of piston lift time vs. richness on acceleration lies. Some guys use 40 wt. I didn't like that. Used ATF for a long time, but it's not what the carbs were designed for. I'm just looking to see if ATF, the 20 wt, or even 15 wt is best in my triple carb set-up. I was really curious here to see if a different oil was spec'd for the triple SU's on a 3000. Seems not. Again - thanks for all the responses!

 

[Keoke]

Used ATF for a long time, but it's not what the carbs were designed for.

Well it really does not depend so much on what the carbs were designed for rather it depends on the condition of the carbs ,Your geographic location and the running temperature of your engine.-Fwiw--Keoke--

 

[Ed_K]

Hi Brent,

I know we have discussed this topic before on the forum but I could not remember what the Driver's handbook and the shop manual had to say about this.
My original handbook quotes " REF D " as the proper lubricant
for the carb dampers.
My handbook has an " AMENDMENT " page fastened inside the front cover listing RECOMMENDED LUBRICANTS.
The " REF D " column is titled " Upper Cylinder Lubricant ".
All of the period lubricants are labeled " U.C.L. " or upper cylinder lubricant.
None of the period products listed in my handbook are available today, at least that I have ever seen under those old names.
...
But Marvel mystery oil has been around for many years. My dad always had a can around in his shop for various uses since I can remember. Marvel mystery oil is labeled / sold as an upper cylinder lubricant which is the same type of product listed in our original handbooks for the carb dampers.
...
I know a couple of folks that have always used Marvel mystery oil in the dampers since back in the late 60s early 70s when they raced LBCs.
...
I along with probably everyone else with SU carbs has experimented with various oils in the dampers for one reason or another. At one time, I thought it may help a little hesitation I had when I floored the gas pedal. Thicker oil seemed to help. After a lot of experimentation with various oils in the dampers, I finally noticed that I had two different length dampers in my carbs ! I also had two different length springs !
Once I installed new correct dampers and springs, I went back to Marvel mystery oil as it seems to work the best in my car once the correct parts were installed in my carbs.
...
From the information that I have learned from the handbook and talking to other LBC owners plus my own observations, Marvel mystery oil is a very good choice and it is available in Walmart or any auto parts store at a reasonable price. Automatic transmission fluid also works and I also use ATF to top off my shock absorbers.

Ed

 

[SkinnedKnuckles]

Ha - I love it! Mystery Oil!!

 

[Ed_K]

https://www.amazon.com/Marvel-MM13R-Mystery-Oil-oz/dp/B0009JKGJW

 

[Patrick67BJ8]

Ha - I love it! Mystery Oil!!

It also is supposed to lubricate the upper end of the engine too.
Patrick

 

[SkinnedKnuckles]

Doing a little searching I come up with this viscosity comparison:

SAE 5 wt - Marvel Mystery Oil
SAE 10 wt - Original 3-in-1 oil
SAE 15 wt - air tool oil (Kobalt)
SAE 20 wt - 3-in-1 Electric Motor 20 wt
SAE 30 wt - Most air compressor oil (ISO 100) or the straight wt motor oil if available.

So it sounds like there is a good range of viscosity used in the dampers. I'll have to get some MMO next time at the parts store. If I don't like it in the dampers I can always add it to the fuel.

 

[tahoe healey]

I wouldn't use Marvel again. It disappeared leaving no resistance in the pistons. I am currently using Moss's oil as I had to pad a bill to make shipping acceptable.I have no idea of its viscosity. It seems OK.

 

[Keoke]

I wouldn't use Marvel again. It disappeared leaving no resistance in the pistons. I am currently using Moss's oil as I had to pad a bill to make shipping acceptable.I have no idea of its viscosity. It seems OK.

WHAT!!! TH, you paid $7.75 to get free shippin---Keoke-- :laugh:

 

[Ed_K]

Hi Tahoe,

Do you know if you have the correct dampers in your carbs ?
I couldn't think of anything other than excessive clearance that would lead to the MM oil disappearing. A lot of other folks besides me have reported that one or both dampers were the wrong part for their car...
But if you are happy with what you are using, don't fix it if it isn't broke.

Ed