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Triumph TR6 - Poor Performance, Low Revs

I have a 75 TR6, about 35000 miles that sat for about 7 years. The car runs ok, carbs have been set and basic maintenance done, but has no low end grunt but cruises fine. A small amount of oil (enough to make your hand damp) comes out of the tailpipes.
What should I do to get some power of the mark?
It has been suggested to me that new piston rings might help?
Alasdair Douglas

Suggest that you have your mechanic do a compression check of each cylinder. You don't say if the exhaust smokes on start up and running, but suggest that you check your spark plugs for burning oil. Low compression and evidence of oil in the cylinders will tell you that rings would be a good idea. While you're at it of course, you should also replace the rod & main bearings, maybe the value seats and whatever else looks like a moving or in contact part!
Doug Baker

No smoke yet and the plugs are slightly fouled.
Thanks for the advice, I will have a compression check done this week.
Alasdair Douglas

No smoke, but oil coming out the tailpipe? I sure would think it'd be smoking.. Maybe it's not timed right? That would cause a lack of power. The advance mechanism may be stuck after all those years, too.

But sitting for that long, the rings may be stuck. And everything may loosen up as you drive it. Change the oil a lot at first. Buy a spare set of plugs and keep one set clean, it'll never run right if they're fouled.

I still think it would be smoking, though.

Gotta agree with should see smoke specifically blue in colour. You should also see low oil pressure on the gauge and high oil consumption.
This liquid coming out the tail pipe or fouling the plugs...does it taste sweet?
Also do you know if 35000 is original miles? You should not have bad rings with that low mileage...stuck like Tom says yes. Is you TR JUST out of 7 years of sitting? What is timing set at?

35,000 miles is just too low a mileage for an engine job.

Alisdair, I presume ON Stands for ONtariario.
Rick C
Rick Crawford

Hi Guys,
Thanks for all your input.
The car came out of storage at the beginning of last summer and the oil has been changed twice, oil pressure is on the high side and oil usage as far as I can judge is about normal for a car of this vintage.
As far as I can tell from the ownwership and service records the mileage is accurate. the car has had three owners before me and seems to have rested for a number of years between each owner.
The exhuast liquid does have a sweet taste, what does this signify? And now that I think about there is a small amount of smoke on starting but not alot.
So, I will do timing check, compression check and see where that gets me.
Alasdair Douglas

It is interesting how just a few answered questions can changer a subject entirely.

"The exhuast liquid does have a sweet taste, what does this signify?"..."oil pressure is on the high side".... The smoke you see would probably be better called steam....I presume white in colour?? Have you had to top up the engine coolant lately on a regular basis?

I would suggest you have a blown head gasket and engine coolant is getting past the head gasket into the cylinder(s). Engine coolant (antifreeze) has a sweet taste to it.
Do not bother with checking the timing. Check compression if you wish to see if one cylinder is very low. Make notes on compression readings. I would do a dry and wet compression test on each cylinder. I would suggest you stop driving your 6 untill this is fixed.
Changing the head gasket is not a very big job but definitely requires some knowledge and special tools.
Alisdair, where abouts in Ontario? There are a lot of Guys on this BBS from ON. It sounds like you bought your 6 last summer.

Rick C '71 TR6
Rick Crawford

"This liquid coming out the tail pipe or fouling the plugs...does it taste sweet?"
Now that's what I call "old school" mechanics!! I'm always learning something new from you guys!
So...all I need now is to get that sweet taste when I get mine running again...
VRROOOM burble burble

Are you saying I am old?
Rick Crawford

No Rick that's not what I was implying.
Our vehicles need be repaired with old technology which I qualify and define with the term "old school".
Qualifications for a Non old school vehicles per my opinion:
(Don't get me wrong, I luv these cars too!!)

1)Must have a shopping cart wing on the back.
2)Stickers such as:
c)"got rice?"
3)Your classic car can't be more than 5 years old or
it will be considered "oLD sKOoL".
4)You exhaust can't be smaller than 20" in
5)Must be able to tune you vehicle with a laptop.

I sure hope this clears it up!
Now go put that shopping cart wing on that tr6!!


Benji...he IS old!!!
Pete (older than him!!)
Pete Russell

WOW!! Pete, you sure started something there...

Pete has asked me to come down to his home next Sun. to help put his engine back together then put it back into his 6.

Guess what Pete?

Young at heart...Rick C
Rick Crawford

Does that mean that you do all the work, while he watches because he's the older guy?
Maybe you should have him taste the liquids leaking out of his newly put together engine...

Benji, are you implying that Rick builds leaky engines??
Pete Russell

Rick Crawford

OOPS! I guess I dug a little hole for myself on that one...

Has anyone (re)built a non-leaky engine? Beyond the 6 month LBC grace period?
Brent B

Ask again in about another 6 months. I may be able to answer yes. Won't know if she leaks until I get 'er done, but it's my intent that she not leak anything anywhere.
Doug Baker

Remember the old saying: It's not leaking, it's just marking its territory.

My rebuilt engine has a new leak at the front...I think the timing chain cover. I know there are bolts/studs/and slotted screws holding it on. Maybe I got a few of the studs and bolts mixed up??
Oh well...another winter project. The back of he 'engine stopped leaking though:)

Doug, I thought the same thing!

If it is not leaking then it is out of oil.

Rick C
Rick Crawford

Back to the original prob. Check the timming. I suspect it is retarded. TRs like advanced timming especially the later ones. Mine is at about 12 degress advanced and runs great.

If it does not leak there is no oil in it.

Aloha all - just saw this after a trip to the mainland. My 6 had sat for about a decade and the distributor advance was gummed up and frozen. I removed, disassembled/lubed/reassembled and had no further problems.
Alasdair - for a quick check, see if the rotor arm is free to move against the advance springs. Good luck!

JB Fetner

Hello again,
Everything has been checked and is ok except the points etc. I have received my new electronic ignition today and intend to install it tommorrow and adjust the timing at that time. I have been reading that with electronic ignition the spark plug gap can be wider. Any suggestions from anyone running electronic ignition.
Thanks everybody for your input.

I have mine set at runs great..I tried 40 for a while and noticed no difference
Charlie B.

Check the oil dampers in you carbs, if they're dry they will be lean on acceleration. Normal mixture check will not show this.

Check compression. If one cylinder is much lower than the rest, Stop driving. If they are down but even, try driving to the coast and back @ 100+ MPH or cross Saskatchewan in under 3 hrs (about all it's good for, OOPS did I say that out loud?).

Check advance with a timing light. It should advance smoothly as you increase revs. How old is the coil?
Set it at 4D btdc idle and advance it until it detonates on acceleration and back it off a few degrees. I have mine at 12D btdc but must run premium.

Ckeck valve clearances, should be 0.010 cold

My car was down in power when I got it and none of these things helped. I decided to rebuild and sent the cam to Shadbolt in Vancouver. He told me he couldn't do anything with it since it was for a GT6. Explains alot. Streeter grind on TR6 cam, 9.5:1 head, 60 over pistons, pretronix ignition, WOW! Burnout city! I'm sure glad gas is cheap and tires free, o wait a minute, I'm gonna be in trouble with the stone cutters (move over Homer).

My freshly rebuilt engine leaked like a sieve from the rear seal. Turns out when the machine shop ground the crank they did the rear seal surface too. Bought a sleeve and pulled the transmission for the tenth (not kidding) time and installed the sleeve. Worked as advertised.

Don Ho

Would the spark plug gap have any impact on oil pressure? Changed plugs today and oil and filter (all same manufacture and spec and my oil pressure guage is all of a sudden reading differently, i.e. too high like 100 unless at idle?


Shawn - Same wt. oil, too? Plug gap will not effect oil pressure to any significant degree. The oil pressure relief valve may be stuck. It's easy to pull & clean without spilling oil. Maybe the old oil was too thin and the new oil pushes the pressure up. There is no advantage to a higher pressure as it puts strain on the pump & takes some power.
Brent B

Brent and all,
The pressure has come down a little after making short runs last night. It still is higher than before. After warming up the motor, at idle, the guage reads 50 or a little below, at regular driving it is at 3/4 or 80ish but at 3000 revs it pegs right up to 100. Otherwise, the TR drives same including power as before. I am pretty confident the oil I put in was the same grade as the oil I removed (20/50) based on the container lable.
Hate to throw away good oil but I am tempted to remove and replenish it again before pulling out the pressure relief valve. Is it pretty easy to remove and clean the oil pressure relive valve? Looked in MOSS, etc., and the parts are pretty inexpensive.
Thanks in advance for your advice.


Rick Crawford is right- a sweet taste indicates the prescence of coolant in your exhaust .

As the TR6 is weel known for pulling very strongly from low revs (and not much above 5000rpm!) I suspect you are losing compression somewhere.

So I agree you should test the compression to confirm the diagnosis, which may be a bad head gasket allowing coolant to leak, and also losing compression.
A new gasket is not that expensive, easy to replace, and while you have the head off you can take a look at the condition of the valves, cylinders etc. and clean out the carbon. You might find with that low mileage you have original valve seats, in which case hardened seats might be worthwhile.

Good luck, Simon.
Simon Rasmussen

OK...lots of help...but where is Alasdair?

Hey Alasdair...let us know what you found out?
Rick C
Rick Crawford

Waiting for the machine shop to return his head, then getting the gumption to put it all back together?

Am I right?

Shawn, I have a car that pegs the oil pressure guage. It bothered me at first, but I drove it a long time. I listened to the noises the engine made, and nothing seemed alarming. It's resting now, so I have no final answer for you. But it's better than no oil pressure, that's for sure.

Happy summer!

Hello everybody,
I ave not been around for a while.
Installed electronic ignition and new plugs, mechanic adjusted the timing and everything is good now.

This thread was discussed between 04/06/2006 and 07/08/2006

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