Unleaded head or not?

[David Arrowsmith]

Hi,

A new boy on here. I have just bought a lovely TR2 in good condition at auction. The previous owner doesn’t seem to want to engage, which is a shame because one of the questions I would like to ask is, has the engine been converted to run on unleaded? (it’s done just 800+ miles since 2010). Is there any way to tell? The guy who recommissioned the TR2 says unless you are doing long journeys it really doesn’t matter, but I would still like to know. Thanks

[Hamish]

Without taking the head off you can’t see if the work has been done. 
you could hedge your bets and use an additive. 
I used to use this as it’s lead replacement, petrol ethanol protection and an octane booster

https://www.millersoils-shop.co.uk/vspe-power-plus-multishot

H 

[Rod1883]

My head hasn't been converted. The mileages and type of driving I do wouldn't make much difference I'm sure - but as per Hamish's advice I use exactly that additive for the three benefits it provides for use with unleaded fuels. I always try to find E0 petrol (there are a few garages around here in Sussex that provide this, but it is only 95 octane), or I'll buy the premium Esso or Shell E5 products.

[RobH]

Welcome to the forums David.  

Short of using an endoscope through a sparkplug hole to look for valve seat inserts, I don't think there is any external way of knowing unless the PO tells you. The accepted wisdom is that the TR engine will be fine without if it is driven normally on the road - it is only a problem if you thrash it often, at high revs. 

[RogerH]

Hi David,

welcome.

Have a look here for cheapo endoscope (but they do work)  Shufftiescope  You would need a 120' reverse view. Or attached mirrors.

Where about's are you.  I have aerospace endoscopes in my shed.  I'm in Hayes near Heathrow airport.

 

Roger

[Tony_C]

Hi David,

Yes, welcome. - you have acquired a wonderful vehicle! 
 

Confirm I agree with the previous responses, I did convert my head back at the beginning 20+ years ago (I was rallying around Europe at the time and got spooked by the propaganda) However, in hindsight I should and could have better left things alone… The old 4pot has to be one of the toughest most robust motors ever made.

[Lebro]

I would only fit the valve seats to "convert to unleaded fuel" if the head had to come off for other reasons.  I ran mine on standard petrol with no additives for 7 years doing around 3000 miles per year with no problems, & when I did eventualy strip the engine for a full rebuild, there was no sign of valve seat erosion.

Bob

[Drewmotty]

48 minutes ago, Lebro said:

I would only fit the valve seats to "convert to unleaded fuel" if the head had to come off for other reasons.  I ran mine on standard petrol with no additives for 7 years doing around 3000 miles per year with no problems, & when I did eventualy strip the engine for a full rebuild, there was no sign of valve seat erosion.

Bob

+1

[mikej]

Agree with all, our mini has never been converted and is fine and the TR ran fine for 8 years without. If, and its a big IF, there is valve seat recession then you fit seats  so may as well enjoy driving it as is? We don't use additives but it may be a good idea to use some provided lead replacement is a key feature. Note that most of the lead in petrol was long gone before 1999, it was not a dramatic change.

 

[billy l]

Mines done 28000 miles with no problems and not converted. I use Castrol Valve Master Plus which gives some protection, If you are concerned you can always occasionally check the valve clearances for tightening up. Cheers, Bill.

[james christie]

I too fell into this hardened insert trap some twenty years ago.

I wish I had thought it out a bit more before spending some serious money. 

Lead free ‘gas’ was introduced in California in the mid seventies and leaded fuel was phased out in the early 90s, I think. A visit to California will show many humdrum family cars, built long before the regulations for lead free gas came into force and thus without inserts or anything else, are still roaming the highways, apparently without problems. And I’m fairly sure that few of their owners add additives.
Given the very low mileages that most of us do in our TRs nowadays, it seems to me to be unnecessary to fit inserts unless valve gaps are beginning to close up - as suggested by billy I.

james

Edited November 17, 2022 by james christie

[David Arrowsmith]

Thanks guys for all your inputs. It sounds like it is much less of an issue than I originally thought and additives seem the way to go. Roger, I used to be a close(ish) M25 neighbour but these days I am in blissful, rural Herefordshire.

[JeffR]

I've owned my 1955 TR3 for 21 years. It retains it's original engine, which is without inserts and runs without additives. I do use a premium grade fuel whenever possible. During this time I've not experienced any problems. It's still going strong and continues to register a very healthy engine compression.

The car does about 3,000 - 4,000 miles a year which includes regular long distance touring in the UK and Europe - in 2019 it took part in the Liege-Brescia-Liege Rally. This year it did the NC500 amongst other trips without fault.

JeffR

[Andy Moltu]

As Bob said it's a job to do when the head is off for another reason not a reason to to take the head off.

Might as well wait until the head is off to check for that matter.

Recession is a variable feast. Low mileage, low rev driving it is negligible but explore the higher revs with a heavy foot and the exhaust valves will get hotter and potentially burn out.

[markaluge]

I have run my TR4 on unleaded since I bought it nearly 40 years ago. I was told that it was a job to do when the valves had burned out. Had to do the head gasket about 8 years ago and they looked fine so I let the sleeping dog be.