TR6 Engine

[Warwick67]

First a confession: I've got a TVR.... BUT it does have a Triumph TR6 engine in it, its a '73 2500 M

I have only recently aquired it and have engine probs..

Nasty knocking suggest big ends have gone, I understand Vandervelle are the bearing to fit but that they are virtually unobtainable - any recommendations?

I have very low oil pressure within 10 minutes of firing it up, I'm wondering if this is a symptom of the big ends or its just that when the oil heats up and thins down it is showing up terminal wear in the oil pump...

Finaly, its got a couple of 2" SU's fitted, which need setting up. Is there anyone out there with a similar set up?

Seen the post about fitting a 2.5 in a Vitesse, I have considered a fuel injection conversion - good idea or bad idea?

Cheers

[Yertis]

The knocking might just be your sump knocked up and being hit by by the crank as it flies round. (as on my TR6 ) But the low oil pressure you describe points to knackered big ends, fortunately not a fortune to fix usually and getting the bits will be easy. Efi is good on this engine, specialists like Revington TR are your friends. Won't be terribly cheap though.

[Pistom]

The standard Lucas fuel injection is very very good but as with all PI systems, it needs to be set up correctly. For a mechanical system such as the Lucas system, your engine needs to be in good condition as it does not cope well with worn bores or leaky valves.

Re the knocking, I'm afraid that sounds like big ends. It is a very easy job as the engine is very simple. I did my TR6 earlier this year and it was a day to get out and strip down, a couple of days at the crankshaft grinders, back at the weekend and all together by Saturday night.

I'd check the condition of your oil pump and thrust washers.

I would get the car running with decent oil pressure and then think about putting the PI setup on after. Having said that - what's wrong with the SUs, they should run OK and give reasonable economy.

Any EFI system is going to be costly to install. It will be as good, even better than the PI system but I've yet to see an install which doesn't look like a hash up from Halfords. If you want to keep the character of the car, I'd go for PI.

[caziques]

All these engine should have 40-60psi oil pressure at 2000 rpm hot (after at least ten miles).

It would be very unlikely that the oil pump is at fault, but don't forget knocking noises can come from pistons.

If you can get the sump off in situ it's possible to change all the bearings without taking the engine out - however a knocking noise suggests a worn crank - in which case it's an engine out job to fit a recon crank. AFAIK heavy duty bearings are available similar to Vandervall - check with Canley Classics.

[varsas]

Warwick67 said:

Finaly, its got a couple of 2" SU's fitted, which need setting up. Is there anyone out there with a similar set up?

Yes, on my XJ6. Been playing with them the last few weeks.

Plenty of guides on line, you just need a carb balancer and a colour tune (from Gunson's, fairly cheap).

http://www.sucarb.co.uk/TechnicalDetail.aspx?id=75

http://classicmotorsports.net/articles/simple-carb... (from 'basic tuning' use the colourtune instead of trying to lift a piston a tiny amount, and the carb balancer instead of listening to a tube).

The spark plugs will give a rough idea of how well the car is running. If the car starts hot and cold, doesn't emit smoke under load, pulls smoothly, all the plugs are a nice colour and the fuel economy isn't too far off the timing and carbs are about right.

http://www.classic-car-magazine.co.uk/articles/spa...

If anyone finds a really simple, step-by-step guide to balancing the carbs I'd be interested. I'm not sure how to disconnect the throttle linkage or what screws to move to change the balance.

[MrF1xa]

That engine with those carbs, if all set up properly and in good condition, will go very nicely. But I wouldn't be worrying about the carbs much at this stage - if I were you I would be going back to basics first. As others have said almost certainly needs big ends as minimum, quite likely a crank grind and main shells as well which means engine out and strip. Driving it too far with low oil pressure will ruin the big ends more and may mean shells start to rotate within the con-rods, at this point the rods and maybe the crank could become scrap.

I would start with a compression test - no point worrying about carbs etc if it has bore and / or valve wear, then go from there. If engine needs to come out and be stripped (doubt you can get the sump off in situ in a TVR) then this is the time to maybe do rings etc and decoke head and valves all in one go.

Edited by MrF1xa on Tuesday 6th September 13:20

[Warwick67]

Thanks, good to know the set up has the potential of a good set up. Look fwd to getting it up and running again.

Cheers
Warwick

[Yertis]

The engine benefits enormously from a decent exhaust manifold, don't know what theh TVRs were shipped with but the standard TR6 manifold is pretty bad (although it does make the car sound nice).