TR3A is sulking

[Richardtr3a]

My car went for the annual MOT today. This means driving for about two hours down to the Cotswolds where we go every year for the test. It usually flies through. This year the tester did not like the front wheel bearing play.He whipped the wheel off ,using my spanners, and made the adjustment. All else was well.

 

The garage is a village business and we were very low on petrol on arrival. You have to climb a steep hill out of the valley near Stroud. We left home early and after two hours, flew up the hill in 2nd gear without any problems. We had the test and I bought 30 litres of their petrol and there was severe pinking as we went to the local for lunch.

 

Is the petrol the problem ,or the timing or am I losing a little end.The noise is only under load and we could cruise at 65mph on the motorway without a problem, until I asked for more.As we approached home the engine stalled afetr pulling up at the lights twice and then ran a bit hot in traffic on the high street.

 

Is my car having a little sulk over the wheel bearing? We need to be ready for CLM and help is needed quickly.

[Alec Pringle]

Hi Richard,

 

odds on stale fuel in the garage tanks . . . .

 

Current fuel formulations deteriorate remarkably quickly (weeks, not months), and that does show up in small village garages with relatively low turnover of fuel. One of our local small filling stations ceased to stock fuel last year for just that reason, they were giving problems to customers. Now they are just workshop and used car sales.

 

Run the tank down and refill with Shell V-Power from a filling station with a high turnover. If you still have a problem, something really is wrong !

 

Cheers,

 

Alec

[TR 2100]

First thing to suspect is the last thing you have done.

All the symptoms could come back to something wrong with

the petrol.

 

AlanR

[Don Elliott]

Richard - Try blowing compressed air into the fuel line just before the glass filter bowl and blow the sediment back into the fuel tank. I had this problem this spring with 7 liters of old fuel left in the tank over the winter where I stored my 1958 TR3A in my warm dry heated gaarge and it solved the problem after I had tried everything else.

 

After that, it ran fine and I've driven 1825 miles so far this May and June with no issues.

 

The photo was taken last week at Mono Cliff Inn (pub) in Ontario about 450 miles from home here in Montreal.

[Richardtr3a]

It looks as if my panic is dying down. Southern Carbutrettors in Wimbledon now have the car and confirm that it is pinking. It was beginning to sound like a little end. I am taking a friend to Le Mans next week so it needs to be 100%.

I am having it tuned for low grade French petrol. All that is left is stop the exhaust rattle and it will be a proper car again.

Thanks for the advice.

Richard

[Alec Pringle]

Hi Richard,

 

nothing low grade about French petrol, Super is 99 octane rather than 98 octane here, or was last summer - I don't think anything has changed.

 

Fill it up with V-Power and have SC tune it to that !

 

Cheers,

 

Alec

[88V8]

I am having it tuned for low grade French petrol.

 

As Alec says, no need. 98 is widely available. Insofar as anything is available, given that a lot of petrol stations shut at 1800h.

 

Ivor

[North London Mike]

As Alec says, no need. 98 is widely available. Insofar as anything is available, given that a lot of petrol stations shut at 1800h.

 

Ivor

 

 

Richard

 

Just putting my 2p in, I agree with Alex & Ivor

 

I had the TR in Le Mans last week (not the 24hr), 98 everywhere, all the way down. No problem

 

Pack some Octane booste,r so even if you're left with 95 you'll be OK

 

Leading the charge next week with the NLG, so see you at the BBQ !!

[67_gt6]

If changing the fuel doesn't sort it, have a look at fuel delivery. I had chronic knocking and eventually tracked it down to some kind of block in the modern inline fuel filter which meant it was underfuelling any time I asked the engine to do anything above 3k RPM.

 

Andy

[Don Elliott]

Richard - Give us a report on the Cox re-built voltage regulator control box. Could that do it ?

[Don Elliott]

Richard - Back in about 1963, I drove my TR3A back home without refueling about 400 miles overnight and arrived home with only dregs left in my fuel tank. After that, the TR was hard to start even after filling it up. Every time I would come to a stop - or if I parked it, it would not want to re-start. Then, after cranking the engine on the starter, it would boom into life again.

 

I found sediment in the bottom of my float bowls and when I was stopped or parked, the sediment setled to the bottom and prevented the fuel from entering the jets in my SU carbs. After finding this, I "mopped" the petrol out the float bowls and the sediment came with it. After that, I never had the problem again. Cranking the engine had un-settled (agitated) the sediment and explains why it would re-start, once the sediment was no longer settled at the bottom blocking the holes to the jets.

[Richardtr3a]

The tuners have fitted new jets, tuned up the mixture and set the timing. However there is still some pinking and they tell me that my compression is too high and that there is the possibility of blowing oil seals.

What is the recommended level. I thought that good compression was important? It looks as if I will make CLM after all.

[Alec Pringle]

Hi Richard,

 

a pound to a penny they're talking bollocks.

 

Your compression ratio doesn't suddenly become too high, the idea is absurd.

 

You have a decent dissie, presumably decent carbs ? There are only two items in my book that will provoke pinking, assuming that the carbs and dissie are set-up correctly. One is **** in the combustion chamber, too much deposition from gentle running. The other is modern fuel of insufficient octane rating and excessive bio-ethanol content. Either way, the thinking man's solution is to run out what's in the tank, chuck in fresh V-Power and a can of fuel system cleaner. Then boot it down the length of the M3 and back at 4000rpm or better. Problem solved.

 

Cheers,

 

Alec

[67_gt6]

Hi Richard, all of this started after that fill up. Have they drained it yet? I would not accept a word they are telling you until they have done that.

 

If the fuel is very bad then normal compression and/or normal ignition timing could cause it to pink due to insufficient octane.

 

Andy

Edited July 2, 2010 by 67_gt6

[Richardtr3a]

Collected the car this afternoon and there is still pinking but much better. They are complaining that my compression I now have two new jets and needles and a tune up. I moved the exhaust to stop the rattle on corners and fixed on the GB plate.Tomorrow may be the first time to take off the hard top in three years before blasting down the M3 to Dorset for a week and then France for the Classic Le Mans week end camping.

I will search out Shell V power and start to relax.I feel that new petrol will help.

Thanks to all who commented.

Richard

[Guest ntc]

It may need a decoke

[james christie]

When you get to France , fill up with 98 octane which is available everywhere. My experience with a modified engine in my 3A is that it always pinks a little when I fill up in UK with your 97 - when I can find it, and of course life is full of angst with the 95 which has to be used on occasion !

 

james

[Don Elliott]

For the past 20 years I've driven my 1958 TR3A 104,000 miles with Shell unleaded fuel, the highest octane I can find. During that time, I have had the head off three times and with modern lead-free fuel, I never saw any carbon build-up that would have been anywhere near to a de-coking condition as I saw and had to deal with from 1958 to 1972.

 

Two weeks ago, I got back from a 1125 miles 7-day trip and had no issues with anything. These TRactor engines just go on forever.

 

In conclusion, it is my experience that de-coking is no longer an issue with modern fuels.

[Richardtr3a]

After an amazing week end at Classic Le Mans we drove back at a leisurely 70 mph and once all the old fuel was used up and I started with 98 octane the pinking disappeared.

I have new jets and SM needles and the plugs are sooting up quite quickly after start up. I have upgraded the plugs to a hotter range and am worried about my compression reading of 190, which the Southern Carb company tell me is the cause of oil burning in the engine and the plug sooting.

I thought that high compression was good and anyway I am not pressurising the sump and not using any oil.

That CLM party is a fantastic week-end of all sorts of classic cars being used in anger. On my ferry on the way back there were only classic cars on board and a huge variety. I am certainly going again in two years. It would be handy to have a bike there to cut down the walking.

Please can someone explain this compression problem to me so that I can understand and look for answers to my plug sooting.

Thank you.

[Alec Pringle]

There is only one way to tune any car - with fresh petrol in the tank. Trying to tune it with suspected stale petrol is a complete waste of time and effort, not to say money.

 

Stale petrol results in the engine running effectively lean, and therefore burning too hot, and therefore giving unrealistically high compression readings - the more so if it's been retarded to counteract pinking. Enrichening the mixture doesn't even address the symptom adequately, and ignores the cause.

 

If the plugs are now sooting, that would appear to confirm the original suggestions of stale petrol - the change of jets and needles may well have been unnecessary, ditto plugs, indeed you may now have to revert to the originals on all counts. Your engine is now, on proper petrol, being overfuelled.

 

Taking note of the advice previously offered by several contributors might have been a quicker and cheaper solution . . . why ask for advice in the first place and then ignore it all ? A waste of everyone's time and effort.

 

Cheers,

 

Alec

[Richardtr3a]

The engine ran much better once the old petrol used up but was still pinking even using high grade Total available locally. On your recomendation I filled up with Shell V power and after the tune up ran down the M3 to Dorchester for a family holiday. It had not been tuned for many years and I did not want to spoil the expedition to Classic Le Mans for my friend and his sons, by lack of maintenance. The car was running very well and the pinking has gone. Before leaving for France I changed the plugs to a hotter grade. We ran this down the Le Mans and back and the sooting is still there.

I never had a problem with petrol before and used any grade available. On your recomendation, Alec, Shell V power and the M3 made a great difference.

I am having trouble understanding the high compression being a fault leading to sooting plugs.

[67_gt6]

What problem are the sooting plugs causing? - aesthetic or mechanical? It sounds like the mixture may be very slightly too rich, the difference between a little rich and spot on can be as little as half of a flat on the adjusting nut.

 

Andy

Edited July 15, 2010 by 67_gt6

[Alec Pringle]

Hi Richard,

 

Total I'm not impressed by - our various Wedges, 4 and 8 pot, are all over 10:1cr . . . they'll pink for France on the high octane Total, yet run perfectly well on Texaco Super, and even better on Shell V-Max. Yet another factor that prejudices me against La Belle France.

 

If an engine is running too hot in the combustion chamber - caused by incorrect distributor timing for example, or by lean mixture, or both - then the gases expand more than normal. If the gases expand more than normal, that will result in an increased reading on the compression gauge if the compression is checked hot. All too easy to be sent up the garden path by this symptom !

 

My suggestion is that **** fuel results in effectively lean mixture, too much air for the fuel, so the engine runs hot combustion and gives deceptively high compression readings. If the tuner tries to cure this by enrichening the mixture, more fuel in other words, it's a temporary 'solution' only - and not a satisfactory one either. Once you're back on decent fuel, the settings are out of the window . . . .

 

Only when the rubbish fuel has gone - run low and then the remainder diluted by two or three refuels - and you're on pukka petrol, will the engine settle down again. As it preumably now has. Then you can tune the beggar accurately. A pound to a penny you'll now find the compressions are back to sensible levels, and the mixture too rich - very possibly the timing in need of a tweak too. Rich mixture is sooting the plugs - the air/fuel charge isn't burning cleanly and completely, leaving soot behind; and of course if the timing is out, that won't help, the charge isn't igniting soon enough, so the mixture isn't burning completely before the exhaust valve opens.

 

Hope that helps ?

 

Cheers,

 

Alec

[Keith Wigglesworth]

I suggest that you have the wheel bearing clearance checked out before your long trip. If the MOT man has tightened it up believing it to be a standard bearing then you may get problems. My MOT man notes loose wheel beartings every year. They do not understand that some play is neded in taper rollers.

[Richardtr3a]

Thanks Keith, willyou be at Malvern? There is still some play on the wheel that he adjusted, so we are probably all right. His advisory was that there was too much play in the 12.00 to 6.00 o'clock axis and not much in the 3.00 to 9.00 axis on the right hand front wheel. He suggested that my hub was worn and needed replacing and that the bearings were all right. Is he right?

The amount of miles that we do each year is not going to make any more apreciable wear anyway.So I am leaving it alone for the moment