4 stroke plugs

[Martin McIntosh]

At one time they marketed OSF plugs under their own name. I run those motors on the same plug up to the point when the idle seems mis tuned. No need to mess with it, just change the plug. Mind you, I used to buy a card of twelve from Probuild for about £2.50 each.

[Paul De Tourtoulon]

£2.50 when was that in the 60's,,,

[Phil Olson - Model Technics]

There are still some Model Technics Supercat 4 Stroke plugs for sale on Ebay

[Jonathan W]

29 minutes ago, Phil Olson - Model Technics said:

There are still some Model Technics Supercat 4 Stroke plugs for sale on Ebay

What happened to the tooling for making the MT plugs, Phil? Did it end up being skipped?

[Engine Doctor]

On 09/07/2023 at 10:15, Cuban8 said:

Yes, I bet they did/still do..................😉

Agreed .....££££££ every 20 flights. Many of my engines have plugs many years old and run just fine. A good way of boosting sales but if it isn't broke don't fix it 

[John Lee]

I've just been sorting out some 1970's Aeromodellers & came across this gem regarding George Aldrich's engine tuning:

 

 

[Paul De Tourtoulon]

24 x 10€ =240€ 😈

[Chris Freeman 3]

My Father in law Jack was also a modeler and once asked the local dealer for advice on glow plugs the dealer stated that a certain brand was good as he sold lots of them, The reply from Jack was if he sold lots then they did not last, he would rather buy the ones he did not sell many of! If the plug is a good quality and the engine run well then the plugs should last. 

[RottenRow]

 

72% Nitro!! Given that there would presumably have been say 20% oil, that’s not a lot left for the methanol.

 

At least this is one engine that could reasonably be named a “nitro” engine, unlike the normal glowplug engines that seem to be annoyingly referred to a “nitro” nowadays.

 

Brian.

[Paul De Tourtoulon]

1 minute ago, RottenRow said:

 

72% Nitro!! Given that there would presumably have been say 20% oil, that’s not a lot left for the methanol.

 

At least this is one engine that could reasonably be named a “nitro” engine, unlike the normal glowplug engines that seem to be annoyingly referred to a “nitro” nowadays.

 

Brian.

I used 55%  Nitro in my OPS spp rear fan .40 with a modified Micro mold fan to get my LMC Mirage off of the ground, (1984) it took one OPS gold plug the most expensive cold plug that the sold to tune in the engine, and a new one for a 5-minute flight.

[Martin McIntosh]

Yes, when I spoke about YS and plugs I was not talking about a day to day cooking engine like a Merco maybe, but a powerful job designed to do a particular task on high nitro, which they do very well; just wish that I could get cheaper plugs. Ordered a couple of OS F ones from ebay at £28 for spares since I have a lot of four stroke motors.

[Phil Olson - Model Technics]

On 10/07/2023 at 11:17, Jonathan W said:

What happened to the tooling for making the MT plugs, Phil? Did it end up being skipped?

Optifuel have all the tooling, parts and Platinum alloy wire, but don't seem to be interested

[Paul De Tourtoulon]

28 minutes ago, Phil Olson - Model Technics said:

Optifuel have all the tooling, parts and Platinum alloy wire, but don't seem to be interested

A shame, at 15€ + for an OS 'F'  and 10€ for two-stroke ones, there is still a market out there.

[Ron Gray]

I would guess that it’s a very, very small market.

[Paul De Tourtoulon]

10 minutes ago, Ron Gray said:

I would guess that it’s a very, very small market.

Yes they are rather small, 😄, I got 20 for our club last year and only 4 or 5 fly IC Methanol, but multiplied by the number of flyers it is worth a try especially as they are tooled up and have the know how, they do sell fuel, and it is the same market.