The Triumph Dolomite Club - Discussion Forum

I HAVE RECENTLY BOUGHT A 1500 HL DOLOMITE I ONLY DO GENTLE MILLAGE I AM NOT SURE IF THE VALVE SEATS HAVE BEEN HARDENED WONDERED IF I SHOULD BE USING A FUEL ADDITIVE OR NOT ANY HELP WOULD BE APPRECIATED THANKS COLIN

Hi, in my own opinion, I would use a fuel additive anyway but if you intend doing very little mileage your main problem might be the fuel "going off" which seems to happen with modern unleaded. Running the car regularily also tends to keep things working the way they should, I found with my Spitfire when i worked away from home on a 3-wks on, 3 wks off rota that I suffered rough running for the first day or so, after that life returned to normal (ish!)
Enjoy!

As I understand, the OHV engines (1300, 1500) are not 'unleaded compatible' unless the head has been specifically rebuilt with hardened valve seats. The same is also true of Triumph straight 6 engines. That being the case a lead substitute such as Castrol Valvemaster should be used.
However, there are some forum members who use their OHV motors gently, without additive, with no significant detrimental effects.
You may, several years/ thousands of miles down the line, need some engine work, at which point hardened valve seats could be fitted.
Other opinions may be offered shortly, I think!!

Me experience with my Spit 1500 is that 130k miles on its still fine.

I regularly cruise at 70 in o/d with just under 3500 rpm. This is about the figure at which valve seat recession is supposed to occur if sustained for long periods.

I never use an additive. The car had done about 70k miles before leaded fuel went out of fashion, so some "lead memory" may be there. I did buy a set of seats and harder valves. They are all still in the drawer.

Jonners

+1 I posted my experiences on a similar thread a week or so back but to briefly summarise, I have covered more miles than most 'hobby' cars will cover in a couple of decades with no,issues whatsoever. Just keep an eye on exhaust valve clearances as they will indicate any issues before they become critical.

And I stated in that post that additives are only good for the additive factory.

Jeroen