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Triumph TR6 - Lucas PI stuff

Just a couple of quick questions directed at the PI guru's.
Has anyone had any luck re doing a metering unit that is seized up from sitting too long? I hate to send it away for a 500 dollar overhaul in the UK, but on the other hand I dont want to screw it up so it is not re-buildable......

My other question is this: I have been using the Bentley manual for most things, but I do have a Haynes manual as well, it makes a note of the "special engine oil filter" only fitted to the PI model. Does anyone know of a difference between a carb and PI engine oil filter???

thanks Mitch ..
Mitch Smith

The consensus of opinion on the UK site from the PI experts is don't mess about with the metering unit, most [all] of the rebuilders in this country won't touch one that's been messed about with.
To the best of my knowledge the PI and the carb models have the same oil filter, whether it's the original or the screw on conversion.
R. Algie

I changed from a carb. to injection engine in my 1976 model TR6,
The new engine had problems with the metering unit.
Then I decided to go for a Bosch L-Jetronic injection
from an Opel Senator 2,5E , 1983 model.
This injection works very well on my engine.

Oystein Nordstronen
Oystein Nordstronen

I'm going to try to stick with the Lucas system for awhile, it is in a TR250 but the PI has not been used for a number of years. It was not inhibited so i am quite sure that is why it is "stuck" I just wondered if anyone in this forum has had any luck dissassembling one, just to clean it out , and re-installing it without having to re-calibrate. It is quite time consuming ( and costly) shipping bits back and forth to the UK. I was hoping to maybe get around it this time..................
Mitch Smith


I hate to have to continue with the "bad news" opinion but there is no cheap way out of this one.

If the unit is actually seized (ie metal to metal contact) rather than just gunked up, it is probably the reason the car was moth-balled in the first place. If it is just gunked up, the chances are that the seals are U/S and the unit will give contiuous headaches if you try and flush it all out with some sort of solvent.

The calibration will definitely be affected if you pull it to bits. The top "castle" can be left untouched, but the fuel cam angle and clearances will be affected. The slightest variation in clearances (and I mean a few thou!) will affect all fuel settings.

The good news is, that once it is set up correctly (and presumably re-conditioned to a reasonable standard) it should give at least a decade of daily use without attention. If you can get the lot done for $500, that sounds a good deal to me. You should also get the injectors reconditioned and the blow-off pressures corecttly adjusted. I can give you a good UK club link for these if you need.

The oil filter is the same for PI's and carb models, but the fuel and air filters are very different.

Hope this helps


Roger H


Stick with the Lucas. For help and assistance go to "The Man" here in the UK, Malcolm Jones at Prestige Injection.

Find him at

then you can drive a TR6 as the designers intended, not the sanitised version sent over to the colonies (totally not politically correct!!!)

Good Luck


T Sharp


His website is

T Sharp

This thread was discussed between 30/10/2005 and 09/11/2005

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