Engine oil 1939 Sq4 and rocker feed

[Paul Tarn]

Hi all
New to ariels and classic bikes. Looking for a bit of advice
Just got an ariel Square 4 1939. The end on the rocker feed pipe leaks (not banjo fibre washers) is it soldered, screwed on etc? Also would anyone recommend Castrol XXL40 as the engine oil. Reading up seems to recommend a low detergent?
Also are there any filters or sludge traps to clean?
sorry if they seem a bit like dumb questions
Paul

[nevhunter]

There's quite a bit you need to check . Someone may point you to the threads here that are relevent. Those earlier oils have changed spec due to cat. converters etc being on modern vehicles. It's not just detergent that's an issue.A SQ4 is helped by having a filter in the return line, but you HAVE to ensure there's no sludge in the crankshaft galleries BEFORE you use it at all. Nev

[paul.jameson]

As Nev says, the first thing to do is clean out the sludge traps in the crankcases. Unfortunately, that involves a total strip down of the engine. Failure to do this leads to a con-rod through the sump and a wrecked engine. There are threads on here which tell you what happens when you ignore this warning which is given to everyone buying a Square Four for the first time.

What we can do to help is give advice on the strip down and reassembly. By the time you have done this, you will know the bike well and have much more confidence in it as a result. Where are you based? There may be a branch of the Club nearby who will be invaluable to you.

[JohnnyBeckett]

hi you have jump into the deep end with a square 4, you will spend a lot of time on the forum and in the workshop good luck with it and welcome to the forum

[Bob.Murphy]

But its worth it when it all comes together (loved my Square Four !).

Bob.

[Paul Tarn]

Thanks for them replies everyone. I wanted to simply ride the bike up and down the street before starting to strip it down. I’m based in Barnsley. I’ll take off the oil feed and check to see if it’s a thread or solder.
I’m mindful of the sagacious advice about oil and seizures which is why I was going to do about 3 or four miles to check gearbox etc before taking spanner’s to her.
Might cut that back to a mile now
Anyway, thanks for the help. This bike will be in my will, she’s going to live with me for hopefully a fair few years. I love it already and I’m going to work on it with the aim to refurb but retain original parts.
Don’t know whether to do the engine myself or send it to a specialist ? Any suggestions welcome - I’m not a mechanic but have stripped bikes and cars in my late teens and early 20s. I have a comprehensive workshop. So it’s personal pride versus just sending it to a professional and getting a beautiful fully reconditioned engine back.
I’ll post some pics of her to the forum - wouldn’t mind talking to someone with an old square 4 though
Paul

[JohnnyBeckett]

hi if you have a good engineering background then i think you can have a go, if not find a good engine builder that understands sq4 engines, they are not a easy engine to get running right they can be a right pain as you will find reading this forum, good luck