• The Roadster Factory Recovery Fund - Friends, as you may have heard, The Roadster Factory, a respected British Car Parts business in PA, suffered a total loss in a fire on Christmas Day. Read about it, discuss or ask questions >> HERE. The Triumph Register of America is sponsoring a fund raiser to help TRF get back on their feet. If you can help, vist >> their GoFundMe page.
  • Hey there Guest!
    If you enjoy BCF and find our forum a useful resource, if you appreciate not having ads pop up all over the place and you want to ensure we can stay online - Please consider supporting with an "optional" low-cost annual subscription.
    **Upgrade Now**
    (PS: Subscribers don't see this UGLY banner)
Tips
Tips

Fuel Additive

Arch 93

Senior Member
Offline
I would appreciate info on lead additives, particularly recommendations about brands. Why do older engines (designed for leaded fuel) sustain damage by running on unleaded?

Thanks
 
A

aerog

Guest
Guest
Offline
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Thomas Speer:
I would appreciate info on lead additives, particularly recommendations about brands. Why do older engines (designed for leaded fuel) sustain damage by running on unleaded?

Thanks
<hr></blockquote>

That depends on the engine. I'm not sure what brands changed what, and when... i'm sure someone can furnish exact serial numbers for unleaded engines, etc. Essentially, though, if you have a pre-catalytic converter car/engine then you might (probably?) have an engine/head designed for leaded fuels.

Some engines, like VW aircooled engines, have valve guides and seats that don't require lead but may require higher octane fuels than originally called for.

In the UK you can take your chances with LRP (lead replacement petrol), which uses potassium as a lead-additive rather than the TEL lead additives. I thought that was neat until I found out that valve-guide wear had increased to terminal levels in some engines that were switched to LRP, along with other problems.

In the states there is, apparently, a product called "relead" which should do the trick for a short-term solution. The problem is, with any "leaded" engine that is run on unleaded (with or without additives) valve guide and seat wear will swiftly become terminal - particularly at highway speeds for extended periods. Additives will slow the effects of the guide/seat wear, but supposedly won't stop it forever.

The end solution to the lead problem is to pull the head off the engine, have new valve guides and seats installed (or just replace the head) - which will provide a permanent solution with unleaded-compatable materials.

Incidentally, some folks will use 100LL (100 Low Lead) Aviation fuel in older cars. I see them all the time at the airport filling up - usually older hotrods that haven't been converted, etc. I guess it works, but whether it's good or bad I have no idea.

Update: Check this web site: https://www.chicagolandmgclub.com/techtips/540.html

[ 03-10-2002: Message edited by: aerog ]</p>
 
Similar threads
Thread starter Title Forum Replies Date
drambuie looking for a good lead fuel additive Austin Healey 5
8 Noisy differential and fuel additive questions Triumph 9
SkinnedKnuckles Any Opinions on Lucas Fuel Additive? Triumph 10
B Fuel Additive for Removing Carbon Austin Healey 2
BOBBYR Fuel additive? Austin Healey 5
A TR6 How many fuel filters-TR6 Triumph 19
Q TR2/3/3A 61 TR3A Fuel Pump Triumph 4
A TR2/3/3A Those round fuel line clips Triumph 2
SherpaPilot TR6 Preping a New Fuel Tank Triumph 7
RJS TR4/4A Tune Up Order - Fuel and Ignition Triumph 5
G MGB ugh.....the fuel gauge went to *** again! MG 8
D Wanted Square body LCS fuel pump Austin Healey Classifieds 13
D Wanted Wanted square body fuel pump Jaguar Classifieds 0
J MGB Jet Tube to Float Chamber Fuel Leak MG 7
roscoe Fuel Gauge Austin Healey 0
D TR4/4A TR4a Fuel Pump Triumph 10
Erica MGB Carburetion and MGB fuel economy. MG 0
Frameman 1949 New Moss Motors Fuel Tank Austin Healey 10
RJS TR4/4A Fuel Pump Gasket Triumph 8
D TR2/3/3A Thread and size for tr3 fuel tank vapor line fitting Triumph 0
RJS TR4/4A Fuel Filters and percolation/ vapor lock Triumph 0
J TR2/3/3A Rear Fuel Line Clips Triumph 3
M TR6 Fuel return line Triumph 8
KVH TR4/4A Routing of TR4A Fuel Line Triumph 7
mctriumph TR2/3/3A Brand new fuel pumps Triumph 8
jfarris For Sale TR4 Fuel Gauge with 2 Transmitters Triumph Classifieds 0
PAUL161 T-Series Fuel Pumps MG 5
D Fuel Gauge Austin Healey 7
Walter74 Fuel Line Routing Austin Healey 7
D MGB Fuel Pump MG 2
Editor_Reid Fuel Tank Interchangeability Austin Healey 2
Martinld123 Electric Fuel Pump Austin Healey 6
S TR2/3/3A Fuel Pump??? Triumph 14
D Fuel Pump Ticking but Not Pumping Austin Healey 8
A Spitfire Fuel Pump Triumph 5
A Spitfire Spitfire Fuel pump issues Triumph 5
K TR2/3/3A Fuel line routing from pump to carbs Triumph 7
BoyRacer Fuel Tank Sending Unit Austin Healey 3
D Fuel Line Clip vs Brake Line Clip Austin Healey 2
T Wanted Working Fuel Gauge for TR3A Triumph Classifieds 5
G Best fuel option for a 72 Midget Spridgets 5
A GT6 Fuel Pump Leaking at out port GT6 MK3 Triumph 0
wkilleffer MGB 1974 MGB SU fuel pump voltage issue MG 11
S fuel pump upgrade Spridgets 0
S Sprite Fuel Pump Upgrade Austin Healey 1
G TR6 Clogged fuel line Triumph 6
9 For Sale Magnetic Aluminum Alloy Fuel Cap for TR250 and pre-1970 TR6 Triumph Classifieds 2
9 TR5/TR250 What is this? Appears to be aluminum fuel cap for TR250 and early TR6 Triumph 13
T TR2/3/3A TR3A Fuel Gauge problem Triumph 10
M Fuel Filler Caps Austin Healey 2

Similar threads

Top