Engine rework / Machinist up north

[Moorey]

Another ive  been happy with Bradford Grinders. http://bguk.co.uk/

[AshimotoK0]

What I was going to ask on the back of this post was if anyone has had their engines bead blasted rather than vapour blasted and if so what was the result.

When I was trying to get to the bottom of my main bearings failing in a CB750 engine that was immaculate inside, the consensus on here was that bead blasting engine parts can lead to unexpected bad things happening - it only takes one bead to get into the tiny oilways in the head that feed your camshaft, for example, and get lodged where you will never find it, to kill your top end.

What I did last year was seal up totally the engines of 3 CB250/350K's with rubber faced items (no engine internals apart from a scrap
camshaft) ..pressure tested up to a few PSI via the breather and soapy water all over to detect leaks. When leak free...I then blasted in our bead blast cabinet with brand new 0/50 grade beads. When finished cleaning....then blast the outside with compressed air and then wash down with acetone then blast again with air. I have recently  seen a firm advertising on the inside  of Tansha VJMC magazine who do exactly the same on a commercial basis (£££). The beads are so fine they give a lovely sheen and because they have not been used on steel, then no iron dust is present in the media to embed into the alloy. Chickened out on my plain main bearing 4 engines though. Having said that the glass is so fine that I think it would polish rather than abrade the internals or cause blockages ....just my take on it ...... just waiting for the 'doubters' to 'kick in' 

Note the engine has no Serial no !!


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[Trigger]

Yes Ash, I am a doubter for many reasons. I used to use silica sand in a blasting unit and stopped for very good reasons. There is a difference if you are cleaning your own engine and if I bit of bead gets in and wrecks the internals, it's a pain in the arse but no one is going to give you grief over it, except yourself !!. But, if it is a customers engine, I will take no risks whatsoever in any of the processes as the customer is paying for a job to be done to an exceptionally high standard and done properly first time. I recall a member on here having his CB400/4 engine vapour blasted and whoever did it absolutely wrecked the engine and the owner, understandably, was very upset and angry. Also, your method is very time consuming and I could not pass on the cost associated with that my customers. So, I will stick to my acid baths for all my engines.

[AshimotoK0]

Yes Ash, I am a doubter for many reasons. I used to use silica sand in a blasting unit and stopped for very good reasons. There is a difference if you are cleaning your own engine and if I bit of bead gets in and wrecks the internals, it's a pain in the arse but no one is going to give you grief over it, except yourself !!. But, if it is a customers engine, I will take no risks whatsoever in any of the processes as the customer is paying for a job to be done to an exceptionally high standard and done properly first time. I recall a member on here having his CB400/4 engine vapour blasted and whoever did it absolutely wrecked the engine and the owner, understandably, was very upset and angry. Also, your method is very time consuming and I could not pass on the cost associated with that my customers. So, I will stick to my acid baths for all my engines.

Perhaps you should change your handle to John George Haigh then Graham !  ..... I stand by my method and once you have made the necessary plugs etc its not time consuming at all. I did three engines in succession... I will copy in a photo  the advert in the VJMC magazine of the company doing it commercially !  Granted if you employ the services of a numpty to do it then  it's fraught with danger like anything else ( welding fuel tanks for example)  ..that's why I try to do everything myself as much as possible. BTW I reckon your bath is more of a solvent bath with de-carbonisers than acid ..as we discussed.

[Trigger]

To me it's acid. It removes all carbon, old lacquer, old paint and draws the oil out of the aluminium..........I wouldn't  advice anyone putting their hand in it because it 'kin burns 

[RGP750]

The Guy Jon has spoken to is one of my customers and really knowledgeable. Jim Norman is his name and he rebored my K0 barrels and overhauled the head totally, he is currently doing my CB175, i'll put up pictures when i get it back.
http://www.milwaukeemuscle.co.uk/index.html