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MG TD TF 1500 - Lead additive?

Recently acquired an MG 1955 TD. Should I add a lead additive to the gasoline?
Marge

Marge - No need to add lead additive to the gas unless you are planning to race the car. Cheers - Dave
David DuBois

In all due respect dave, I disagree.

About two years ago, I got a call from a gal in the Cornwall Ont. area. She was asking why her TF was losing power despite haveing a full carb re-build and tune-up.

I suggested she get a compression test which turned out to be terrible - all in the 50 to 65 lb range.

It turns out she drives the car abt. 5,000 a summer and has been using unleaded gas ever since it was introduced. Removal of the head brought out her worst fears. The valves were nearly in the passages and almost beyond the point of repair.

She had the head repaired professionnaly and had stainless seats installed.

Gord Clark
Rockburn, Qué.
Gordon A. Clark

Gordon,

I disagree with you, I will bet her problem was due to running too lean, not from no-lead gas. I put 35,000 miles on my TF 1500 after rebuild without inserts, using our wonderful no lead gas. When the engine was rebuilt last year after overheating due to a lost freeze plug while on tour, the valves and seats were still in good shape. (The cam was toast due to no Zinc oil)

Our local super rebuild expert has stated that he does not put seats in iron heads (T, MGA, MGB, midget Sprite, etc.) and has NEVER SEEN A FAILURE DUE TO NO-LEAD GAS in all the years since the US changeover.

In his experience, burned valves and seats always come from running too lean.
(This can happen with a few hundred miles at expressway speeds and running too lean, as my daughter found out on her 74 MGB new engine, After the 2nd rebuild and correct tuning put 25,000 miles with no problems. She often made the trip to Tallahassee in record times on back roads, averaging pver 70 MPH from the time it took)

I totally agree with Dave, from my own and our club members experience.

If you race the car, leaded 100 plus octane is available at the track, so you don't need inserts there either, with all the problems induced by inserts.

Don Harmer

I'm afraid we'll have to agree to disagree.

The lady in Cornwall had her carbs rebuilt because they would only run on the rich side.

Anyway, lead additive so comparatively inexpensive, so why take a chance? To me, its best to err on the safe side.

Gord Clark
Rockburn, Qué.
Gordon A. Clark

gord, you have done so much to help people here on the forum, but i take exception to your advice as well. lead was added to gas as an anti-knock compound and now it is the miracle valve lubricant. i have opened up a couple of engines for my '35 hudson that were removed from service before lead was removed from gasoline. they only ran on LEADED gas their entire time in service...all...i repeat all of the valve seats were recessed. they had not burned one drop of unleaded fuel. lead is deadly to humans. you are not erroring on the conservative side by adding a lead substitue, you are poisoning our children. please, save your money and our offspring. don't add lead. regards, tom,
tm peterson

Gordon - I will agree that over a long period of time, the valves will resess as happened to the lady in Cornwall. To be more correct, I should have said that while the damage is minimal, the valves will ultimately need attention sooner that if leaded fuel or a lead substitute is used. I have nearly 80,000 miles on our TD since leaded fuel has not been available and so far, the valves are ok, but eventually I will need to have hardened seats installed. In the meantime, I will continue as I have for the past 25 years, ignoring the problem until the modification is needed. I had to put hardened valve seats in our MGB finally a couple of years ago after following the same routine with it. Since it is our primary transportation vehicle, the valve seats in it wore much faster than in the TD. Cheers - Dave
David DuBois

Don,

So what oil or additive do you use to help your new cam?

Thanks,
Scott
Scott

I'm certainly not going to line up on either side of this question, since almost anyone knows more about XPAG/XPEG valves than I do. Certainly Gord and Dave could bury me.
That being said, I have had a 1951 TD for 7 years now and I've added a lead substitute all the time I've had it - as a prophylactic measure. Doesn't seem to have any bad effect, MIGHT defer the day when I have to have hardened valve seats installed. I use CD2 Lead Substitute. Available in the USA at Walmart, smuggled into Canada. I err on the side of less is better, at MOST 1 oz per 10 gallons (US) or 1/4 oz'per 10 litres.
Ted Jackson

By all means, err on the side of caution and use an lead substitute additive, but you don't need the extra cost of seats,( which some think essential) the iron does very well, and the hardened seats sometimes come loose with disasterous results.

Scott
As to OIL, I use what Crane recommends on replacing cam and tappets,
( and so does Bob Wagner at our Tech Session at AIAP in Jan. He also discussed the LN Engineering Report on the Zinc Concentrations).

Namely: Shell Rotella T Diesel Oil, 15W40 and will switch to RedLine after 3000 miles breakin. Castrol HD 30 was also suggested for breakin.

For our well broken in cars, don't use any oil marked "Energy Saving" or any oil wit the first number less than 15 (ie 5Wxx or 10Wxx)

It appears that Castrol 20W50 and Valvoline VR1 20W50, most motorcycle oils, Mobile 1 V Twin 20W50 (or any oil specifically prepared for air cooled engines and 20W50), all with Zinc above 1200 ppm, can be used.

The above from a report by Charles Navarro and Tammy Hellings of LN Enginnering for Porsche of America on oils suitable for air cooled engines.(also applicable to Flat Tappet engines)
Don Harmer

Marge, you came to the right web sight, all the help you will ever need. We have a local chapter of British cars WWW.bccswf.com ,although based in Fort Myers, several members in Naples. You are welcome to join if you are interested.

Jojn Shoemaker
John Shoemaker

don, i disagee with you. stick with your original thought. there is NO documented evidence of valve seat recession caused by unleaded fuel, so why advocate adding a lead substitute. it seems sort of like running 110 octane gas in our motors to err on the side of caution to prevent preignition. i could then tell a story of never having experienced preignition so therefore 110 octane is what i would recommend. i have been following this since the gov't announced lead would be removed from our fuels. the folk lore tale of impending doom started 20 years ago and has persisted. a number of auto restoration magazines have studied this. "Skinned Knuckles, A Journal of Automotive Restoration" , Monrovia,Ca. ran field tests. their conclusions were published at the time...the removal of lead did not cause any adverse effects on vintage motor valve seats. lead in fuel kills people, hardly erring on the side of caution. save your money, help save the planet. leave the lead substitute where it belongs...on the store shelves. regards, tom
tm peterson

I am of the impression that almost all products desribed as lead replacements do not, in fact, contain lead. These products use other active ingredients (if they work at all).

Note the active ingredients listed in products tested by the Federation of British Historic Vehicle Clubs:

http://www.fbhvc.co.uk/fuel/additives.htm

Federation of British Historic Vehicle Clubs lead substitute study:
http://www.morrisminoroc.co.uk/articles/alltherest/FBHVC_tests.html

http://www.triumphshop.co.uk/Quiller/Unleaded/federation%20info.htm

I use Red Line Lead substitute, which is one of the products suggested by FBHVC to provide some beneficial characteristics:
http://www.redlineoil.com/whitePaper/12.pdf

Larry
Larry Shoer

The triumphshop link appears to work when typed manually into the address field. It does not work when clicked on in my posting above.

Larry
Larry Shoer

Least we forget. Lead was not initially added to fuel to assist the valve train. It was an additive used to reduce/prevent engine knock. Interestingly, Alcohol was found to also prevent knock. The story of how alcohol was knocked (no pun intended)out of gasoline and lead was added.

Here is an article on this topic (if you can get past the writers slight negative attitude, it does cover many of the facts.)
http://jove.eng.yale.edu/pipermail/eas-info/2005/000792.html

To add to the issue, My engine was rebuilt in 1980 and I did not have it build "unleaded" Had it redone last year and the valves were found to be in excellent shape and no damage to the head. That is with about 1000 miles a year.

BTW Do a search of this topic and you will see just about the exact same pro and con arguments on every car group page out there. Most of what I read says if you do not tow or go for prologed high rev, non-hardened heads will do just fine.
BEC Cunha

I want to thank the many people who responded to my question about my 55 TF. Although I am very confused now, I will continue to research through the various websites offered here. Once again, thanks. I will remain in Naples a couple more months. Marge
M Waligura

Have put 14000 miles on my stock engine on regular old (new) unleaded...
gblawson - TD#27667

This thread was discussed between 03/02/2007 and 13/02/2007

MG TD TF 1500 index

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