Thread: 2A on unleaded

Originally Posted by bent

Gday all

Just about to get my 68 2A running, just wondering how to run unleaded in it, ie fuel additives etc???????

Thanks all!!
Cheers

Ben

Theoretically you need to either run with hardened valve seats or with a lead substitute additive in unleaded (no octane enhancer is needed, even with the rare 8:1 head) since the exhaust valves seat in cast iron. However, it is worth noting that this engine was sold in Canada with no modifications and apparently no trouble for several years after leaded petrol ceased to be available. General opinion seems to be that it is unnecessary to do anything unless you are doing a lot of sustained high power, high rpm work such as freeway driving. And even if valve seat recession starts, it will show up as exhaust valve clearances closing up - and will not affect your ability to fit hardened valve seats, as the valve seat area of the head has to be machined out anyway to fit them.

I have now been running my 2a as a daily driver on unleaded for over four years, with no additives and no hardened valve seats - and no closing up of tappet clearances. About a year ago I had the head off for a decoke and to replace the valve stem seals - the valve seats were in almost perfect condition.

So my advice is to just put the unleaded in the tank and run it! If it has had the timing set for leaded petrol you will find it necessary to retard the spark by about three degrees, but preignition will soon let you know about this!

John

JDNSW - would your comments apply to a 1974 Series III GS 6cyl as well? I was advised by the previous owner to add lead replacement fluid with each fill of the tank. It starts very well, seems to run fairly well although it doesn't appreciate hills and I get a backfire when I turn the engine off.

Dear God I appreciate the likes of JDNSW and Phillip A they know thier stuff never comes out with drivel and is pretty well always spot on.
I think these guys are a testament to this website and I ALWAYS appreciate what they have to say.

Disco Dave be wary of the F engine it probably needs to run some form of upper cylinder lubricant to cope with unleaded and is a very different beast than the 2.25 litre four.
I use to run an upper cylinder lubricant in these things 25 years ago with super petrol and still had issues
I would be very careful what I did with these in the fuel climate of today.

Originally Posted by DiscoDave

JDNSW - would your comments apply to a 1974 Series III GS 6cyl as well? I was advised by the previous owner to add lead replacement fluid with each fill of the tank. It starts very well, seems to run fairly well although it doesn't appreciate hills and I get a backfire when I turn the engine off.

I don't have the experience on that engine. However, my parts book tells me it has steel valve seat inserts, which means that it does not require a lead replacement fluid as a lubricant, and with the highest compression being 7.8:1, it will not need an octane enhancer either, although the timing may need adjusting.

The backfire when turning the engine off has nothing to do with the use of unleaded, but may reflect other problems, as may the problem with hills. This engine has a reputation for burning exhaust valves unless clearance is closely attended to, and in fact it was suggested in another thread that this be set a couple of thou wider than specified to allow for the higher ambient temperatures in Australia. I would check your compression, as a burnt exhaust valve may be your problem. Also check that the mixture is correct.

Sorry I can't help more than this, but I have no first hand experience of the six.

John

bug 1.0 a 66 2a ran just fine on unleaded and never gave me any problems while I had her on the petrol donk. I reckon she did some 80,000km while i had her. she ran unleaded cause I was cheap and dint care about the engine since I was putting a diesel in her (bug 1.0 is now kermit).

Same engine is now powering a SWB III somewhere in townsville and i havent heard tickety boo from the bloke who got the engine. (and has been since some time in 2003 so far as I know)

If you did get recession as previously mentioned fit harder seats and maybe valves, Im partial to the stainless ones when you do do them but thats just me and my overkill engineering principals.

I was using the 2.25 Petrol as a daily driver with a lot of high speed work for about 10 years using ULP. I found that once I started using ULP I had trouble getting a really smooth tune. This problem was resolved by having the distributor re-weighted. It was done by Scorcher Ignition in Nunawading (VIC), and the guy there explained that the Land Rover 4cyl never pings, it has more than 30 degrees of vacuum advance, which is too much for the ULP.

While you're at putting your 2.25 on the road, you may want to consider upgrading to electronic ignition. I went for the optical Pirhana one after having been stranded by poor quality condensors & points from various suppliers. It was explained to me that since cars now a days use electronic ignitions, it's hard to source good quality points. For awhile there I was not getting more than 2,000km hassle free between sets of points.

G'day DiscoDave

Sounds like your 2.6ltre 6 cyl is a little retarded, the setting for the timing on 90 Octaine fuel, (unleaded is 91 oct) is 2 degrees ATDC (After Top Dead Centre) to adjust timing with timing light, disconnect the Vacc advance first.

Before you do, I would suggest that you remove the dist cap, and remove Vac hose/tube from Carby, suck through it, and if the points plate in the Dist doesn't move the Vacuum diaphragm is seized or dead.

Repair or replacement, contact Kevin Baker K.B. Classic Parts, (07)5494 4221, fax (07)5494 4114. Quote the Dist part number,stamped on side.

or contact Mike Bushnell at Advance Diaphragm Options, (07)5428 0808,
www.advancediaphragmoptions.com as he does exchange units, quote distributor type and part number, that is the best I can advise

cheers