I have been using TCP for quite a while in my 1946 C-85 equipped Ercoupe running both 100LL and Mogas. I ran out of TCP and on the advice of several folks started using MMO in my fuel (Mogas only) instead of TCP. After 50 hours on my new plugs I pulled them to clean and rotate them. I was shocked at the amount of gunk on the plugs. I never had oily buildup using TCP. I’ve switched back to using only TCP in my fuel. Next 50 hour check will tell the story although I probably already know the results given I had only used TCP previously. I don’t know what my valves look like, but when we did a top overhaul about 100 hours ago after using TCP the valves were clean.

Randy B Verified Purchase

Alcor TCP Fuel Additive Quart

Perfect

Saubion Verified Purchase

Alcor TCP Fuel Additive Quart

Keeps the plugs clean when running leaded fuel.

Jeff W Verified Purchase

Alcor TCP Fuel Additive Quart

Works great in my Continental O-470 engine originally designed to run on 80 octane fuel. No lead fouling. Plugs always look good when checked. No deposits. Highly recommend for 80 octane engines.

James W Verified Purchase

Alcor TCP Fuel Additive Quart

Haven’t ran long enough yet

Clay C Verified Purchase

Alcor TCP Fuel Additive Quart

Absolute necessity in my Lycoming O-235-C1

Paul B Verified Purchase

Alcor TCP Fuel Additive Quart

Easy to use with the dispenser. Put it in the fuel a week ago.

Joseph S Verified Purchase

Alcor TCP Fuel Additive Quart

A very effective lead scavenger and especially useful in selected Lyco engine configurations. Combined with proper leaning, TCP has essentially eliminated plug contamination!

J. P Verified Purchase

Alcor TCP Fuel Additive Quart

I have been using Alcor TCP for several years and have found it to be effective in preventing lead deposits on my spark plugs and valves.

Richard S Verified Purchase

Alcor TCP Fuel Additive Quart

Hoping it works and keeps the engine running for many hours to come

Paul R Verified Purchase

Alcor TCP Fuel Additive Quart

Seems to keep the engine healthy

Paul R Verified Purchase

Alcor TCP Fuel Additive Quart

I have been using this product for quite a while and have found it to preform as it advertises. No lead build up at all. My engine loves it..

Perry S Verified Purchase

Alcor TCP Fuel Additive Quart

Most of it leaked out in the package

Ben H Verified Purchase

Alcor TCP Fuel Additive Quart

Excellent product. My old TCM engine would not run very well for long without it!

Dan B Verified Purchase

Alcor TCP Fuel Additive Quart

Just started using so have not noticed any difference but a friend who uses regularly and recommended swears by it.

Jay S Verified Purchase

Alcor TCP Fuel Additive Quart

Have used TCP since the end of 80 octane avgas availability, with good results.

William R Verified Purchase

Alcor TCP Fuel Additive Quart

All the experts say it can’t hurt to use TCP so hopefully it’s keeping our engine happy!

Paul R Verified Purchase

Alcor TCP Fuel Additive Quart

our mechanic says spark plugs are free of lead deposits at every annual since we started using tcp several years ago.we have not had any leaking exhaust valves since using it,we had several problems prior.

Larry S Verified Purchase

Alcor TCP Fuel Additive Quart

‘necessary when running “low lead” gasoline in a low compression aircraft engine. Continental A75. Don’t leave the ground without it.

Dave Y Verified Purchase

Alcor TCP Fuel Additive Quart

Works very well on all of my aircraft

Andrew B Verified Purchase

Alcor TCP Fuel Additive Quart

alcor works just great in my Jabiru 3300. Been using it for eight years and every year at annunal the plugs are always clean.

Bob O Verified Purchase

Alcor TCP Fuel Additive Quart

Great product, but would definitely like to see a better method for dispensing. The plastic syringe is junk!

Paul R Verified Purchase

Alcor TCP Fuel Additive Quart

Works well.

Glenn M Verified Purchase

Alcor TCP Fuel Additive Quart

No problem

Karl S Verified Purchase

Alcor TCP Fuel Additive Quart

O-320 has no sparkplug fouling issues when this product is used. Plugs stay clean.

Rick D Verified Purchase

Alcor TCP Fuel Additive Quart

I use it for my C90 engine to lubricate the engine.

Ismael B Verified Purchase

Alcor TCP Fuel Additive Quart

Great Product

Steve W Verified Purchase

Alcor TCP Fuel Additive Quart

This will help keep your engine from leading up using 100LL. However, this is a hazardous material, and Ive been told a carcinogen, so use carefully.

D. R Verified Purchase

Alcor TCP Fuel Additive Quart

Have used Alcor TCP faithfully for over 15 yrs in my Grumman Tiger’s Lyc 0-360. With fairly aggressive leaning on the ground and just ROP in the air, my plugs have never shown any notable lead build-up at annual. Not so prior to TCP. Great product in easy to use containers with calibrated syringe.

J. P Verified Purchase

Alcor TCP Fuel Additive Quart

The best thing for my engine

Chris R Verified Purchase

Alcor TCP Fuel Additive Quart

A must have with Chevy engines. Doesnt hurt the older Continentals either

Belted A Verified Purchase

Alcor TCP Fuel Additive Quart

A must for my 2 stroke engine running 100LL Good stuff.

Jim D Verified Purchase

Alcor TCP Fuel Additive Quart

so far so good. Havent noticed any fouling in 3 fill ups

Jay O Verified Purchase

Alcor TCP Fuel Additive Quart

No problem with Alcor, it is highly recommended for low compression engines to keep the led in 100ll suspended (less plug fouling)

Karl S Verified Purchase

Alcor TCP Fuel Additive Quart

I put this in a Stearman and have not had plugs foul out, yet.

Richard T Verified Purchase

Alcor TCP Fuel Additive Quart

My aircraft has a Continental O-470S1B engine which was certified as an 80 octane engine. I have been using TCP in my engine for 27 years since 80 octane fuel has not been available for several decades. My engine runs very smoothly and I havent had a problem with lead fouling while using TCP. Every time my plugs are pulled, they are very clean with minimal deposits. I am convinced that the smooth operation and longevity of my 80 octane engine is due to my use of TCP fuel additive.

James W Verified Purchase

Alcor TCP Fuel Additive Quart

Expensive, but does help keep the plugs (massive electrode) from fouling and easy to clean.

Joseph C Verified Purchase

Alcor TCP Fuel Additive Quart

This product reduces chance of lead fouling and heat stress on cylinders due to lean burn setting on mixture control.

C-air Verified Purchase

Alcor TCP Fuel Additive Quart

Good stuff. Happy it got delivered!!

Simon F Verified Purchase

Alcor TCP Fuel Additive Quart

Great product, lousy packaging. They always leak. Last shipment was empty and had to be re-ordered. They really need to change the container

Goodfriend A Verified Purchase

Alcor TCP Fuel Additive Quart

spark plugs are staying very clean

I was skeptical when I bought a Stinson with a Franklin engine and was introduced to Alcor/TCP. One look at the plugs at annual and we started using it in a Cessna 150 with an O-200. You simply cant believe how clean your plugs are after 50 hours of burning 100LL.

I have used this product for over 30 years. Keeps the plugs clean in my O300D. I did like the gallon size better.

I was having detonation issues (up to 3 times) after pulling the mixture out when cutting the engine in my Continental E225-8, almost embarrassing. My mechanic asked me to start using this product and upon the next flight, then engine did not have the pre-ignition / detonation occurrence 3 times. I use the 30 ml to 10 gallons and have used about 3 times thus far and it seems to be working as I barely get any spit or sputter after pulling the mixture. As current, I will keep using this product and currently I definitely recommend as it seems to be helping quite a bit and I do not see any negative to engine temps, exhaust gas temps. Very pleased so far. 9/1/2020

Cant fly my Stinson with a 165hp. Franklin without it.

Spark plugs stay clean, no more lead balls

Im convinced this stuff works. Dramatic reduction in lead oxide on the spark plugs at annual time.

I use this product religiously. So far, so good.

Been using for years great product

works well on my old planes

TCP has been very effective in reducing spark plug leading between annuals on my Continental 0-200 engine. The price is higher than I remember paying in the past. I hope you can negotiate lower prices in the future.

I use religiously in my Beech Musketeer & Cherokee 6. Highly recommended to reduce spark plug fouling...

Have been using Alcor TCP for 20 years. Keeps the plugs in my Grumman Tiger whistle clean and free of lead deposits. esp with aggressive leaning as recommended during ground ops. A necessity for some carburated engine configurations.

TCP is exactly what it is advertised as. :) The only problem is that many times the lids are not tight and it leaks in the shipping.

The Lycoming O235 in my C152 is very prone to spark plug fouling from the lead in 100LL. TCP fuel treatment has completely eliminated that problem. The engine runs better too. My A&P notices the difference during my annual inspection.

Using this product makes Spark plug fouling and sticking valves a thing of the past !!! And....Spruce sells it at an unbeatable price. (I saw this product sell for 74$ )

I don’t usually bother to “rate” products but as an A&PIA and pilot/CFI that’s been a professional in the aviation community for a bit over 50 years I have had numerous small Continental owners limp in with sticking valves as a result of TEL (tetraethylead) fouling. TCP is the one, faa “approved” solution. It will NOT remove existing deposits and it’s a bit pricy but it DOES prevent the problem. Without is all A, and C series and particularly C-145/O300 will lead foul on 100 L L. Even a mix of autogas and 100 eventually end with sticking valves (and plugs).

Good stuff. Never a problem with fouled plugs on my O-320!

My Cherokee 180 was having issues with fouling and valve deposits. After using TCP in two successive tanks my O-360 is running perfectly smooth and plugs are clean with no lead deposits. I now use TCP in every or every other tank fill up.

My engine seems to have better power and starts up first blade spin since Ive been treating the fuel. although i run fine wire plugs i get 0 lead fouling now very happy.

Definitely makes a difference in the performance of my 64 C150D.

a fair price and quick delivery

A Top Shelf product and highly recommend.

I have been using TCP for a couple of years now in my C-182 (bladder tanks) and have found it to be very effective in reducing lead fouling on the plugs and lead deposits in general. The stuff needs to be handled carefully. (Package says not to get it on your paint.) Hauling it around and injecting it at every fill is inconvenient. I bought a sealed plastic container to keep it in ($10 from Amazon search on: LOCK & LOCK Airtight Square Tall Food Storage Container 135.25-oz / 16.91-cup) and that gives me peace of mind when Im carrying it in the baggage area (which is all the time). Sure, I wish it was cheaper... but I think the advantages outweigh the cost or I wouldnt keep buying it. I found the shipping charges to be reasonable. I usually get at least 2 cans per order.

Very effective in my 165 Franklin

I have been using this product in two RV-12 aircraft with the Rotax 912 for the past three years. In comparison to Dekalin it keeps the oil and the spark plugs cleaner and removes the lead better. Great product!

Started using TCP in my Stearman W670 Continental at 100 hours SOH Valves and plugs are clean the fine wire plugs can be cleaned with a small blast of air from the portable compressor. No more fouling ever.

Started using this after I replaced all 4 cylinders on my Continental O-200. After 1 year and 100 hours, plugs were the cleanest plugs I had ever seen in an aircraft engine and the compressions were all 80/80! Highly recommend this product!!

The product makes a world of difference in my Lycoming IO-540 as far as lead fouled plugs goes. It simply is no longer an issue. Bit of a hassle injecting it with each fuel fill, but worth the effort and cost to me. Have used it for several years now.

My Carbon Cub would get black/grey lead film on the shocks/landing gear just aft of the exhaust that was really hard to get off. As soon as I started using TCP, the pesky film all but stopped. Also just scoped all cylinders, and did not find any lead deposits on exhaust valves or Pistons at 200 hrs.

From day one new, had a terrible time with the Lycoming IO-540 in my Commander 114B lead fouling plugs when ground running @ 1200 RPM, even with the fuel leaned. Sitting long in line for take-off or IFR clearance would almost guarantee a bad mag check. Not good, especially at a large and busy airport. Went to fine wire plugs which helped a lot. But for a 100% cure, have used TCP for the last several years. Wouldnt fly without it. Wish they would go back to gallon containers though. Was cheaper than 4 individual quarts.

This product is awsome, used as directed it will absolutely prevent lead fouling no fouling means no plug cleaning pays for itself.

During a tail wheel endorsement training I noted the Cub owner, A&E, w/IA, & CFI refueled with this (Alcor's TCP Fuel Additive). He explained the benefits, and success. When I finished the restorization of my J3, with A75-8 I started using it. I have been using it now for the last 500 hours, in 7 years. At annual, my IA says keep using it. Compressions, and exhaust valves are great. It hurts me to hear stories from pilots of stuck exhaust valves in the small engines.

Heard about TCP from a Cub driver, hoping it will make plug fouling a thing of the past. So far it has been easy to use, the syringe fitting in the can works very well... :)

Donn C Verified Purchase

Alcor TCP Fuel Additive Quart

Great product to cut down on fouled spark plugs & valves. Just wish the provided a better syringe dispenser. I’ll give 5 stars when they do.

Paul R Verified Purchase

Alcor TCP Fuel Additive Quart

It works

Paul B Verified Purchase

Alcor TCP Fuel Additive Quart

Works great, shipping is terrible though.. played down in box bolth times... shipped twice still dont have a full bottle

Dont know why you shipped from Georgia to Oregon. No leaks, no dents: OK.

Seems to reduce the lead on the plugs by half, which I think is great. Been using and will continue using.

Great Product! Ridiculous charge for shipping!

The can had leaked. And I had a real problem getting the top off. I was getting 1 out of 4 tries. I tried another three times with same results. 1 out of 4. I called Alcor and explained the leak and top problem. The guy said it was probably a bad top. He would have another Alcor employee call me. Nothing. Alcor customer support is nonexistent.

Ed S Verified Purchase

Alcor TCP Fuel Additive Quart

Need to find different product. Cap is impossible to open, yet leaks. Continuing problem

Herb L Verified Purchase

Alcor TCP Fuel Additive Quart

Seems to help keep the spark plugs clean. The dispenser is not easy to use. Over priced. Lid on can does not seal well. Two cans leaked when shipped.

I’ve been using TCP Religiously for two years on my C-85. I’m doing a top overhaul now and the tops of my pistons and the interior of my cylinders and valves were heavily carbon deposited. So, I’m not sure TCP has helped or not. I will continue using it since I have two cans and then look closely at the plugs to see what they reveal. If clean, I’ll give another review.

Randy B Verified Purchase

Alcor TCP Fuel Additive Quart

Can leaked, everything was wet. Top was taped but still leaked.

Doug M Verified Purchase

Alcor TCP Fuel Additive Quart

Once again the can leaks in the shipping process. Not the first time. Needs a different type top

Jon C Verified Purchase

Alcor TCP Fuel Additive Quart

Haven’t used the product yet because of the container top it comes with! If a syringe is required to use this product, then include it with the product when you ship it! For the cost of the product, it should certainly be included if it is needed for use. Was no mention of a syringe needed when I ordered from aircraft spruce. Would think there would be a better way to dispense product from the container. Or just have a normal top so product could be dumped into a measuring cup of some sort.

The shipment arrived poorly packed and some of the packaging was damp because at least one of the containers spilled during shipment. My pilot said the shipment was ok to accept.

My engine would run beautiful on no lead auto gas, CA screw ups messed that up with the 10% alcohol. No clean auto gas to be found in CA !! Now I have to add TCP to the 100LL and still had 2 Exhaust valves mess up, excess lead, within 1 1/2 years. Replace with overhauled $600 cylinders. My hourly rate is skyrocketing, blaming it on the Sacramento Gang. Just venting do not know what would happen without TCP

Great stuff, but buy in person shipped UT spills everywhere

Frank J Verified Purchase

Alcor TCP Fuel Additive Quart

Product is great, but bottle leaked during shipping. almost 1/4 of its contents. Cap was loose.