TR6 PI system

[ewj]

I currently have a Herald Convertible but fancy a TR6. However, it would not be used for some 3-4 months over the winter (salt and muddy lanes). Whilst no classic car likes to be laid up for any length of time, is the PI system (even with a Bosch conversion) more problematic in that respect, such that I would be better off with a carburetor version or a TR4? Existing TR6 owners' experiences would be appreciated.

[Pete Lewis]

if you keep the battery on a cheap trickle charger (aldi/lidl)  and fire it up once in a blue moon all classics are fine when over wintering 

th PI is self priming  so evaporation from open carbs is not a factor 

Pete

 

[johny]

I thought one problem was the lines to the injectors emptying over time and then it can be a pig trying to refill them cos you need hydraulic pressure to open the injectors. Obviously does depend on the tightness of the system and how often you start it...

[Russell1972]

I have two TR6s and neither of them get used much this time of year. As Johny said, it does seem to come down to how well the injection system is sealed. One of them, even if left for a just a couple of weeks, takes a good 1 to 2 minutes of cranking before it will fire on enough cylinders to keep running. The other, probably only needs 30 seconds or less, but that’s on a hi-torque starter motor, so spins a bit faster. Both are on Bosch pumps. They have been left for 3 months occasionally, but once started and running on all 6 cylinders, they’ve been fine.

I’ve owned them for 15 and 10 years respectively, and they both run really well and pull like trains, so I’m reluctant to investigate tinkering with the injection to try and improve starting after a lay-up.

But to answer your question, I haven’t had any real issues.

Russell

Edited February 6 by Russell1972

[Paulfc]

I’ve had my 6 since 2019. Limited use over the winter when I tend to service/uprate/modify and generally tinker. I try to take it out at least once a month for a run but occasionally it sits for a couple months between startings. As an example, I started it last night having replaced the tachometer cable and, as I probably won’t be able to take it for a run for at least a week or so, wanted to ensure all was well. It was previously out and about mid December. Switched on the ignition and let the Bosch pump prime for 30 seconds, pulled the “choke” fully out and it fired first time. The 30 second prime period definitely seems to make a difference. Also, as has been mentioned, a “cheap” trickle charger is an excellent investment.

Paul

[Nigel Clark]

Don't worry about laying up a PI Triumph for a few months during winter. My TR6 starts okay after being dormant for a couple of months in winter. However, to get enough fuel moving through the injectors needs a good quality battery that's well charged. It may start on only a few cylinders at first, but they all chime in soon enough.

With Lucas PI, I've enjoyed both the driving experience and the learning curve of maintaining the system. It's a wonderfully idiosyncratic way to get fuel into an internal combustion engine!

Nigel

[PeteH]

De-ja-vu, here. In the 70`s my Electrician on one Ro-Ro ferry had one (TR with PI), Because he wanted to do some work on it, it was onboard the ship for over a Month. We finished up towing this car up and down a car deck in Immingham for hours, Using a "Maffi" tug, swapping batteries, tinkering with it, we did eventually get it running and he left the Ship. I understand he got it back home OK.

Pete

[johny]

Yes as I understand it if you have empty injector lines the solution is to take out the injectors and hold open their poppet valves (not sure how this is done) while spinning the engine. This allows the air to be pushed out by the fuel so that once the lines are full the poppet valves will operate normally...

[Nigel Clark]

No need to lift the poppet valves to bleed the injectors.

Remove the spark plugs and coil power feed (the wire from the ignition switch). Take out the injectors and raise as high as possible then point them into a pot to catch the fuel. Crank the engine on the starter until fuel pulses from all six injectors.

Put everything back together and the engine should start first time.

Nigel

[JohnD]

Each to their own!   If you do want to release the injector valves, then there are two types.   One has a 'needle' projecting from the sharp end, the other does not.   To release the valve, pull on the needle with your finger nails , never pliers!

The other type you can't do this, end of story:

 

JOhn

[johny]

3 hours ago, Nigel Clark said:

No need to lift the poppet valves to bleed the injectors.

Remove the spark plugs and coil power feed (the wire from the ignition switch). Take out the injectors and raise as high as possible then point them into a pot to catch the fuel. Crank the engine on the starter until fuel pulses from all six injectors.

Put everything back together and the engine should start first time.

Nigel

I thought the problem was if the pipe is empty the air inside just gets compressed by the pulses so not applying enough force to open the injector poppet valve and venting becomes difficult. In this case manually opening the poppet (if possible) rectifies the situation however maybe this is an extreme scenario such as on first fire after a rebuild....

[Nigel Clark]

I've never needed to lift the poppet valves on my TR6's injectors to bleed the PI system, even after replacing the injector pipes and fitting new seals to the metering unit.

Nigel

[ewj]

Many thanks to all who replied.